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Pancreatic stellate cells (PSCs) contribute to pancreatic ductal adenocarcinoma (PDAC) progression and therapeutic resistance, yet their detailed functions remain unclear. This study combined RNA sequencing and assay for transposase‐accessible chromatin using sequencing (ATAC‐seq) on sorted PSCs from adjacent normal and PDAC tissues to investigate their transcriptional and epigenetic activation. PSCs heterogeneity and functions are characterized through bulk, single‐cell, and spatial transcriptomes, as well as in situ sequencing. The clinical relevance of PSCs in immunotherapy is assessed using an in‐house immune‐checkpoint blockade (ICB) treatment cohort. Findings showed that stress and hypoxia signaling activated PSCs in PDAC. Three common PSCs (CPSCs) and four tumor‐associated PSCs (TPSCs) are identified, each with distinct functions. CPSCs differentiated into CCL19+ TPSCs in immune‐enriched regions, MYH11+ TPSCs in the stromal region, and PLXDC1+ TPSCs, which exhibited cancer‐associated myofibroblasts (myCAFs) phenotype linked to poor prognosis. Notably, PLXDC1+ TPSCs, located near aggressive LRRC15+ myCAFs and SPP1+ macrophages, formed a desmoplastic and immunosuppressive niche around the tumor boundary, promoting CD8 T cell exhaustion. Single‐cell transcriptomics of PDAC patients treated with ICB revealed that PLXDC1+ TPSCs correlated with poor immunotherapy efficacy. Overall, this study provides key insights into PSCs in PDAC and potential therapeutic targets. This study uncovers the activation, heterogeneity, and regulatory roles of pancreatic stellate cells (PSCs) at single‐cell and spatial levels. It further identifies PLXDC1+ PSCs near aggressive LRRC15+ cancer‐associated myofibroblasts and SPP1+ macrophages, forming a desmoplastic and immunosuppressive tumor niche that promotes CD8+ T cell exhaustion, contributing to poor immunotherapy outcomes in pancreatic cancer.

P3HT/PCBM-based polymer solar cells (PSCs) were fabricated using conventional and inverted device architectures. Conventional PSCs were annealed at various temperatures ranging from room temperature (RT) to 180°C. At 130°C, the PSC exhibited enhanced device performance with efficiency of 2.64%. PSCs with oxide (TiO2/ZnO) interlayers were found to play an effective role in enhancing the photovoltaic (PV) properties of the cells, providing an energy step that efficiently contributes to the extraction and transport of electrons. The power conversion efficiency (PCE) of the as-prepared oxide (TiO2/ZnO)-based inverted PSCs was 3.16% and 2.32%, respectively, compared with efficiency of 0.77% for the reference device. The difference in efficiency followed a trend similar to that reported in our previous study. The photovoltaic (PV) properties of inverted PSCs were also tested at various annealing temperatures ranging from RT to 110°C. Interestingly, TiO2-based PSCs exhibited higher performance than ZnO-based inverted devices, suggesting that the interfacial electron transfer and recombination rates were effectively tuned because of the presence of TiO2 between the working electrode and the device’s active layer (AL).

The biomechanical environment plays a dominant role in fracture healing, and Piezo1 is regarded as a major mechanosensor in bone homeostasis. However, the role of Piezo1 in fracture healing is not yet well characterized. In this study, we first delineated that Piezo1 is highly expressed in periosteal stem cells (PSCs) and their derived osteoblastic lineage cells and chondrocytes. Furthermore, downregulation of Piezo1 in callus leads to impaired fracture healing, while activation by its specific agonist promotes fracture healing through stimulation of PSC-modulated chondrogenesis and osteogenesis, along with accelerated cartilage-to-bone transformation. Interestingly, vascular endothelial growth factor A is upregulated after Yoda1 treatment of PSCs, indicating an indirect role of Piezo1 in angiogenesis. Mechanistically, activation of Piezo1 promotes expression of Yes-associated protein (YAP) and its nuclear localization in PSCs, which in turn increases the expression and nuclear localization of β-catenin. In detail, YAP directly interacts with β-catenin in the nucleus and forms a transcriptional YAP/β-catenin complex, which upregulates osteogenic, chondrogenic and angiogenic factors. Lastly, Yoda1 treatment significantly improves fracture healing in a delayed union mouse model generated by tail suspension. These findings indicate that Piezo1 is a potential therapeutic target for fracture delayed union or nonunion.The biomechanical environment plays a dominant role in fracture healing, and Piezo1 is regarded as a major mechanosensor in bone homeostasis. However, the role of Piezo1 in fracture healing is not yet well characterized. In this study, we first delineated that Piezo1 is highly expressed in periosteal stem cells (PSCs) and their derived osteoblastic lineage cells and chondrocytes. Furthermore, downregulation of Piezo1 in callus leads to impaired fracture healing, while activation by its specific agonist promotes fracture healing through stimulation of PSC-modulated chondrogenesis and osteogenesis, along with accelerated cartilage-to-bone transformation. Interestingly, vascular endothelial growth factor A is upregulated after Yoda1 treatment of PSCs, indicating an indirect role of Piezo1 in angiogenesis. Mechanistically, activation of Piezo1 promotes expression of Yes-associated protein (YAP) and its nuclear localization in PSCs, which in turn increases the expression and nuclear localization of β-catenin. In detail, YAP directly interacts with β-catenin in the nucleus and forms a transcriptional YAP/β-catenin complex, which upregulates osteogenic, chondrogenic and angiogenic factors. Lastly, Yoda1 treatment significantly improves fracture healing in a delayed union mouse model generated by tail suspension. These findings indicate that Piezo1 is a potential therapeutic target for fracture delayed union or nonunion.

Renewable energy-based solar photovoltaic (PV) generation is the best alternative for conventional energy sources because of its natural abundance and environment friendly characteristics. Maximum power extraction from the PV system plays a critical role in increasing the efficiency of the solar power generation during partial shading conditions (PSCs). Therefore, a suitable maximum power point tracking (MPPT) technique to track the maximum power point (MPP) is of high need, even under PSCs. This paper presents an organized and concise review of MPPT techniques implemented for the PV systems in literature along with recent publications on various hardware design methodologies. Their classification is done into four categories, i.e. classical, intelligent, optimal, and hybrid depending on the tracking algorithm utilized to track MPP under PSCs. During uniform insolation, classical methods are highly preferred as there is only one peak in the P-V curve. However, under PSCs, the P-V curve exhibits multiple peaks, one global maximum power point (GMPP) and remaining are local maximum power points (LMPP's). Under the PSCs, classical methods fail to operate at GMPP and hence there is a need for more advanced MPPT techniques. Every MPPT technique has its advantages and limits, but a streamlined MPPT is drafted in numerous parameters like sensors required, hardware implementation, cost viability, tracking speed and tracking efficiency. This study provides the advancement in this area since some parameter comparison is made at the end of every classification, which might be a prominent base-rule for picking the most gainful sort of MPPT for further research.

Mesenchymal stem cells (MSCs) possess a broad spectrum of therapeutic applications and have been used in clinical trials. MSCs are mainly retrieved from adult or fetal tissues. However, there are many obstacles with the use of tissue-derived MSCs, such as shortages of tissue sources, difficult and invasive retrieval methods, cell population heterogeneity, low purity, cell senescence, and loss of pluripotency and proliferative capacities over continuous passages. Therefore, other methods to obtain high-quality MSCs need to be developed to overcome the limitations of tissue-derived MSCs. Pluripotent stem cells (PSCs), including embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs), are considered potent sources for the derivation of MSCs. PSC-derived MSCs (PSC-MSCs) may surpass tissue-derived MSCs in proliferation capacity, immunomodulatory activity, and in vivo therapeutic applications. In this review, we will discuss basic as well as recent protocols for the production of PSC-MSCs and their in vitro and in vivo therapeutic efficacies. A better understanding of the current advances in the production of PSC-MSCs will inspire scientists to devise more efficient differentiation methods that will be a breakthrough in the clinical application of PSC-MSCs.

In this paper, a new hybrid TSA-PSO algorithm is proposed that combines tunicate swarm algorithm (TSA) with the particle swarm optimization (PSO) technique for efficient maximum power extraction from a photovoltaic (PV) system subjected to partial shading conditions (PSCs). The performance of the proposed algorithm was enhanced by incorporating the PSO algorithm, which improves the exploitation capability of TSA. The response of the proposed TSA-PSO-based MPPT was investigated by performing a detailed comparative study with other recently published MPPT algorithms, such as tunicate swarm algorithm (TSA), particle swarm optimization (PSO), grey wolf optimization (GWO), flower pollination algorithm (FPA), and perturb and observe (P&O). A quantitative and qualitative analysis was carried out based on three distinct partial shading conditions. It was observed that the proposed TSA-PSO technique had remarkable success in locating the maximum power point and had quick convergence at the global maximum power point. The presented TSA-PSO MPPT algorithm achieved a PV tracking efficiency of 97.64%. Furthermore, two nonparametric tests, Friedman ranking and Wilcoxon rank-sum, were also employed to validate the effectiveness of the proposed TSA-PSO MPPT method.

Although lead‐based perovskite solar cells (PSCs) are highly efficient, the toxicity of lead (Pb) limits its large‐scale commercialization. As such, there is an urgent need to find alternatives. Many studies have examined tin‐based PSCs. However, pure tin‐based perovskites are easily oxidized in the air or just in glovebox with an ultrasmall amount of oxygen. Such a characteristic makes their performance and stability less ideal compared with those of lead‐based perovskites. Herein, how to address the instability of tin‐based perovskites is introduced in detail. First, the crystalline structure, optical properties, and sources of instability of tin‐based perovskites are summarized. Next, the preparation methods of tin‐based perovskite are discussed. Then, various measures for solving the instability problem are explained using four strategies: additive engineering, deoxidizer, partial substitution, and reduced dimensions. Finally, the challenges and prospects are laid out to help researchers develop highly efficient and stable tin‐based perovskites in the future. Nontoxic tin‐based perovskite solar cells (PSCs) have attracted attention, but are easily oxidized, which causes their performance and stability to be far behind lead‐based PSCs. Here, strategies to improve the stability of tin‐based PSCs (additive engineering, deoxidizer, partial substitution, and reduced dimensions) are reviewed. Outlooks are also proposed to avoid the shortcoming for fabricating highly efficient and stable PSCs.

Inverted perovskite solar cells (PSCs) have been extensively studied by reason of their negligible hysteresis effect, easy fabrication, flexible PSCs and good stability. The certified photoelectric conversion efficiency (PCE) achieved 23.5% owing to the formed lead−sulfur (Pb−S) bonds through the surface sulfidation process of perovskite film, which gradually approaches the performance of traditional upright structure PSCs and indicates their industrial application potential. However, the fabricated devices are severely affected by moisture, high temperature and ultraviolet light due to the application of organic materials. Depending on nitrogen, cost of protection may increase, especially for the industrial production in the future. In addition, the inverted PSCs are found with a series of issues compared with the traditional upright PSCs, such as nonradiative recombination of carriers, inferior stability and costly charge transport materials. Thus, the development of inverted PSCs is systematically reviewed in this paper. The design and fabrication of charge transport materials and perovskite materials, enhancement strategies (e.g., interface modification and doping) and the development of all−inorganic inverted devices are discussed to present the indicator for development of efficient and stable inverted PSCs.

[This corrects the article DOI: 10.3389/fimmu.2024.1452195.].