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Perovskite solar cells (pero-SCs) have undergone a rapid development in the last decade. However, there is still a lack of systematic studies to investigate whether the empirical rules of working lifetime assessment used in silicon solar cells can be applied to pero-SCs. It is commonly believed that pero-SCs show enhanced stability under day/night cycling due to the reported self-healing effect in the dark.1,2 While we discovered that the degradation of highly efficient FAPbI3 pero-SCs is in fact much faster under natural day/night cycling mode, questioning the widely accepted approach to estimate the operational lifetime of pero-SCs based on continuous mode testing. We reveal the key factor to be the lattice strain caused by thermal expansion/shrinking of the perovskite during the operation, an effect that gradually relaxes under the continuous-illumination mode but cycles synchronously under the cycling mode.3,4 The periodic lattice strain under the cycling mode results in deep trap accumulation and chemical degradation during operation, decreasing the ion migration potential and hence the device lifetime.5 We introduce phenylselenenyl chloride (Ph-Se-Cl) to regulate the perovskite lattice strain during day/night cycling, which achieved the certified efficiency of 26.3% and a 10-time improved T80 lifetime under the cycling mode after the modification.
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In Arabidopsis thaliana, brassinosteroid (BR) signaling and stomatal development are connected through the SHAGGY/GSK3-like kinase BR INSENSITIVE2 (BIN2). BIN2 is a key negative regulator of BR signaling but it plays a dual role in stomatal development. BIN2 promotes or restricts stomatal asymmetric cell division (ACD) depending on its subcellular localization, which is regulated by the stomatal lineage-specific scaffold protein POLAR. BRs inactivate BIN2, but how they govern stomatal development remains unclear. Mapping the single-cell transcriptome of stomatal lineages after triggering BR signaling with either exogenous BRs or the specific BIN2 inhibitor, bikinin, revealed that the two modes of BR signaling activation generate spatiotemporally distinct transcriptional responses. We established that BIN2 is always sensitive to the inhibitor but, when in a complex with POLAR and its closest homolog POLAR-LIKE1, it becomes protected from BR-mediated inactivation. Subsequently, BR signaling in ACD precursors is attenuated, while it remains active in epidermal cells devoid of scaffolds and undergoing differentiation. Our study demonstrates how scaffold proteins contribute to cellular signal specificity of hormonal responses in plants.
Assuntos
Proteínas de Arabidopsis , Arabidopsis , Brassinosteroides , Divisão Celular Assimétrica , Quinase 3 da Glicogênio Sintase , Transdução de Sinais , Diferenciação Celular , Arabidopsis/genética , Proteínas Quinases/genética , Proteínas de Arabidopsis/genéticaRESUMO
Cellular responses to internal and external stimuli are orchestrated by intricate intracellular signaling pathways. To ensure an efficient and specific information flow, cells employ scaffold proteins as critical signaling organizers. With the ability to bind multiple signaling molecules, scaffold proteins can sequester signaling components within specific subcellular domains or modulate the efficiency of signal transduction. Scaffolds can also tune the output of signaling pathways by serving as regulatory targets. This review focuses on scaffold proteins associated with the plant GLYCOGEN SYNTHASE KINASE3-like kinase, BRASSINOSTEROID-INSENSITIVE2 (BIN2) that serve as a key negative regulator of brassinosteroid (BR) signaling. Here we summarize the current understanding of how scaffold proteins actively shape BR signaling outputs and crosstalk in plant cells via interactions with BIN2.
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Stability and current-voltage hysteresis stand as major obstacles to the commercialization of metal halide perovskites. Both phenomena have been associated with ion migration, with anecdotal evidence that stable devices yield low hysteresis. However, the underlying mechanisms of the complex stability-hysteresis link remain elusive. Here we present a multiscale diffusion framework that describes vacancy-mediated halide diffusion in polycrystalline metal halide perovskites, differentiating fast grain boundary diffusivity from volume diffusivity that is two to four orders of magnitude slower. Our results reveal an inverse relationship between the activation energies of grain boundary and volume diffusions, such that stable metal halide perovskites exhibiting smaller volume diffusivities are associated with larger grain boundary diffusivities and reduced hysteresis. The elucidation of multiscale halide diffusion in metal halide perovskites reveals complex inner couplings between ion migration in the volume of grains versus grain boundaries, which in turn can predict the stability and hysteresis of metal halide perovskites, providing a clearer path to addressing the outstanding challenges of the field.
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Cell transplantation is a promising treatment option for spinal cord injury (SCI). However, there is no consensus on the choice of carrier scaffolds to host the cells. This study aims to evaluate the efficacy of different material scaffold-mediated cell transplantation in treating SCI in rats. According to PRISMA's principle, Embase, PubMed, Web of Science, and Cochrane databases were searched, and relevant literature was referenced. Only original research on cell transplantation plus natural or synthetic scaffolds in SCI rats was included. Direct and indirect evidence for improving hind limb motor function was pooled through meta-analysis. A subgroup analysis of some factors that may affect the therapeutic effect was conducted to understand the results fully. In total, 25 studies met the inclusion criteria, in which 293 rats received sham surgery, 78 rats received synthetic material scaffolds, and 219 rats received natural materials scaffolds. The network meta-analysis demonstrated that although synthetic scaffolds were slightly inferior to natural scaffolds in terms of restoring motor function in cell transplantation of SCI rats, no statistical differences were observed between the two (MD: -0.35; 95% CI -2.6 to 1.9). Moreover, the subgroup analysis revealed that the type and number of cells may be important factors in therapeutic efficacy (P < 0.01). Natural scaffolds and synthetic scaffolds are equally effective in cell transplantation of SCI rats without significant differences. In the future, the findings need to be validated in multicenter, large-scale, randomized controlled trials in clinical practice. Trial registration: Registration ID CRD42024459674 (PROSPERO).
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Transplante de Células , Traumatismos da Medula Espinal , Alicerces Teciduais , Animais , Traumatismos da Medula Espinal/terapia , Ratos , Alicerces Teciduais/química , Transplante de Células/métodos , Metanálise em Rede , Resultado do Tratamento , Recuperação de Função FisiológicaRESUMO
BACKGROUND: Exosomes can penetrate the blood-brain barrier for material exchange between the peripheral and central nervous systems. Differences in exosome contents could explain the susceptibility of different individuals to depression-like behavior after traumatic spinal cord injury (TSCI). METHODS: Hierarchical clustering was used to integrate multiple depression-related behavioral outcomes in sham and TSCI rats and ultimately identify non-depressed and depressed rats. The difference in plasma exosome contents between non-depressed and depressed rats after TSCI was assessed in 15 random subjects by performing plasma exosome transcriptomics, mass spectroscope-based proteomics, and non-targeted metabolomics analyses. RESULTS: The results revealed that about 27.6% of the rats developed depression-like behavior after TSCI. Totally, 10 differential metabolites, 81 differentially expressed proteins (DEPs), 373 differentially expressed genes (DEGs), and 55 differentially expressed miRNAs (DEmiRNAs) were identified between non-depressed TSCI and sham rats. Meanwhile, 37 differential metabolites, 499 DEPs, 1361 DEGs, and 89 DEmiRNAs were identified between depressed and non-depressed TSCI rats. Enrichment analysis showed that the progression of depression-like behavior after TSCI may be related to amino acid metabolism disorder and dysfunction of multiple signaling pathways, including endocytosis, lipid and atherosclerosis, toll-like receptor, TNF, and PI3K-Akt pathway. CONCLUSION: Overall, our study systematically revealed for the first time the differences in plasma exosome contents between non-depressed and depressed rats after TSCI, which will help broaden our understanding of the complex molecular mechanisms involved in brain functional recombination after TSCI.
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Exossomos , MicroRNAs , Traumatismos da Medula Espinal , Humanos , Ratos , Animais , Depressão/etiologia , Exossomos/metabolismo , Fosfatidilinositol 3-Quinases , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/metabolismoRESUMO
Understanding charge transport in conjugated polymers is crucial for the development of next-generation organic electronic applications. It is presumed that structural disorder in conjugated polymers originating from their semicrystallinity, processing, or polymorphism leads to a complex energetic landscape that influences charge carrier transport properties. However, the link between polymer order parameters and energetic landscape is not well established experimentally. In this work, we successfully link statistical surveys of the local polymer electronic structure with paracrystalline structural disorder, a measure of statistical fluctuations away from the ideal polymer packing structure. We use scanning tunneling microscopy/spectroscopy to measure spatial variability in electronic band edges in PM6 films, a high-performance conjugated polymer, and find that films with higher paracrystallinity exhibit greater electronic disorder, as expected. In addition, we show that macroscopic charge carrier mobility in field effect transistors and and trap influence in hole-only diode devices is positively correlated with these microscopic structural and electronic parameters.
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Complex multi-element alloys are gaining prominence for structural applications, supplementing steels, and superalloys. Understanding the impact of each element on alloy surfaces due to oxidation is vital in maintaining material integrity. This study investigates oxidation mechanisms in these alloys using a model five-element equiatomic CoCrFeNiMn alloy, in a controlled oxygen environment. The oxidation-induced surface changes correlate with each element's interactive tendencies with the environment, guided by thermodynamics. Initial oxidation stages follow atomic size and redox potential, with the latter becoming dominant over time, causing composition inversion. The study employs in-situ atom probe tomography, transmission electron microscopy, and X-ray absorption near-edge structure techniques to elucidate the oxidation process and surface oxide structure evolution. Our findings deconvolute the mechanism for compositional and structural changes in the oxide film and will pave the way for a predictive design of complex alloys with improved resistance to oxidation under extreme conditions.
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The abuse of antibiotics has caused a serious threat to human life and health. It is urgent to develop sensors that can detect multiple antibiotics quickly and efficiently. Biosensors are widely used in the field of antibiotic detection because of their high specificity. Advanced artificial intelligence/machine learning algorithms have allowed for remarkable achievements in image analysis and face recognition, but have not yet been widely used in the field of biosensors. Herein, this paper reviews the biosensors that have been widely used in the simultaneous detection of multiple antibiotics based on different detection mechanisms and biorecognition elements in recent years, and compares and analyzes their characteristics and specific applications. In particular, this review summarizes some AI/ML algorithms with excellent performance in the field of antibiotic detection, and which provide a platform for the intelligence of sensors and terminal apps portability. Furthermore, this review gives a short review of biosensors for the detection of multiple antibiotics.
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Inteligência Artificial , Técnicas Biossensoriais , Humanos , Algoritmos , Antibacterianos , Processamento de Imagem Assistida por ComputadorRESUMO
BACKGROUND: The epidermis of cotton ovule produces fibers, the most important natural cellulose source for the global textile industry. However, the molecular mechanism of fiber cell growth is still poorly understood. RESULTS: Here, we develop an optimized protoplasting method, and integrate single-cell RNA sequencing (scRNA-seq) and single-cell ATAC sequencing (scATAC-seq) to systematically characterize the cells of the outer integument of ovules from wild type and fuzzless/lintless (fl) cotton (Gossypium hirsutum). By jointly analyzing the scRNA-seq data from wildtype and fl, we identify five cell populations including the fiber cell type and construct the development trajectory for fiber lineage cells. Interestingly, by time-course diurnal transcriptomic analysis, we demonstrate that the primary growth of fiber cells is a highly regulated circadian rhythmic process. Moreover, we identify a small peptide GhRALF1 that circadian rhythmically controls fiber growth possibly through oscillating auxin signaling and proton pump activity in the plasma membrane. Combining with scATAC-seq, we further identify two cardinal cis-regulatory elements (CREs, TCP motif, and TCP-like motif) which are bound by the trans factors GhTCP14s to modulate the circadian rhythmic metabolism of mitochondria and protein translation through regulating approximately one third of genes that are highly expressed in fiber cells. CONCLUSIONS: We uncover a fiber-specific circadian clock-controlled gene expression program in regulating fiber growth. This study unprecedentedly reveals a new route to improve fiber traits by engineering the circadian clock of fiber cells.
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Fibra de Algodão , Gossypium , Perfilação da Expressão Gênica , Fenótipo , Expressão Gênica , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismoRESUMO
Cost management and toxic waste generation are two key issues that must be addressed before the commercialization of perovskite optoelectronic devices. We report a groundbreaking strategy for eco-friendly and cost-effective fabrication of highly efficient perovskite solar cells. This strategy involves the usage of a high volatility co-solvent, which dilutes perovskite precursors to a lower concentration (<0.5 M) while retaining similar film quality and device performance as a high concentration (>1.4 M) solution. More than 70% of toxic waste and material cost can be reduced. Mechanistic insights reveal ultra-rapid evaporation of the co-solvent together with beneficial alteration of the precursor colloidal chemistry upon dilution with co-solvent, which in-situ studies and theoretical simulations confirm. The co-solvent tuned precursor colloidal properties also contribute to the enhancement of the stability of precursor solution, which extends its processing window thus minimizing the waste. This strategy is universally successful across different perovskite compositions, and scales from small devices to large-scale modules using industrial spin-coating, potentially easing the lab-to-fab translation of perovskite technologies.
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Brassinosteroid (BR) hormones are indispensable for root growth and control both cell division and cell elongation through the establishment of an increasing signalling gradient along the longitudinal root axis. Because of their limited mobility, the importance of BR distribution in achieving a signalling maximum is largely overlooked. Expression pattern analysis of all known BR biosynthetic enzymes revealed that not all cells in the Arabidopsis thaliana root possess full biosynthetic machinery, and that completion of biosynthesis relies on cell-to-cell movement of hormone precursors. We demonstrate that BR biosynthesis is largely restricted to the root elongation zone, where it overlaps with BR signalling maxima. Moreover, optimal root growth requires hormone concentrations to be low in the meristem and high in the root elongation zone, attributable to increased biosynthesis. Our finding that spatiotemporal regulation of hormone synthesis results in local hormone accumulation provides a paradigm for hormone-driven organ growth in the absence of long-distance hormone transport in plants.
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Brassinosteroides/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Brassinosteroides/biossíntese , Regulação da Expressão Gênica de Plantas , Meristema/metabolismo , Redes e Vias Metabólicas , Reguladores de Crescimento de Plantas/fisiologia , Raízes de Plantas/metabolismoRESUMO
Cotton is an important natural fiber crop, however, its comprehensive and high-resolution gene map is lacking. Here we integrate four complementary high-throughput techniques, including Pacbio long read Iso-seq, strand-specific RNA-seq, CAGE-seq, and PolyA-seq, to systematically explore the transcription landscape across 16 tissues or different organ types in Gossypium arboreum. We devise a computational pipeline, named IGIA, to reconstruct accurate gene structures from the integrated data. Our results reveal a dynamic and diverse transcriptional map in cotton: tissue-specific gene expression, alternative usage of TSSs and polyadenylation sites, hotspot of alternative splicing, and transcriptional read-through. These regulated events affect many genes in various aspects such as gain or loss of functional RNA motifs and protein domains, fine-tuning of DNA binding activity, and co-regulation for genes in the same complex or pathway. The methods and findings provide valuable resources for further functional genomic studies such as understanding natural SNP variations for plant community.