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Abstract Achieving efficient and stable blue light‐emitting perovskite nanocrystals is a significant challenge for next‐generation optoelectronic devices. Here, a dual‐ligand surface engineering strategy is reported for quasi‐2D CsPbBr₃nanoplatelets (NPLs) synthesized via ligand‐assisted reprecipitation. By synergistically co‐introducing didodecyldimethylammonium bromide to passivate bromine vacancies and hexylphosphonic acid to bind undercoordinated lead ions, the NPLs achieved a remarkable photoluminescence quantum yield of 93.7% and a narrow full‐width at half‐maximum of 19.27 nm. The enhanced photoluminescence (PL) lifetime (6.35 ns), reduced crystal disorder, slower bleach recovery kinetics, and improved thermal stability suggest that the suppressed non‐radiative pathways and strong exciton confinement (Eb = 141.76 meV) result from effective surface defect passivation and enhanced radiative recombination. Additionally, surface and structural characterizations confirmed the successful dual‐ligand integration and improved crystal integrity. The treated NPLs retained ∼57% PL under 450 min of ultraviolet (UV) light and ∼55% PL under 70% relative humidity, demonstrating strong UV and moisture stability. A prototype white light‐emitting device fabricated by integrating dual‐ligand‐treated NPLs achieves a wide color gamut (121% National Television System Committee, 90.4% ITU‐R Recommendation BT.2020), demonstrating their potential for high‐performance optoelectronics. This approach promotes defect suppression in low‐dimensional perovskites, paving the way for stable and efficient blue emitters. 

Both chronic and acute drought alter the composition and physiology of soil microbiota by selecting for functional traits that preserve fitness in dry conditions. Currently, little is known about how the resulting precipitation legacy effects manifest at the molecular and physiological 1 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 available under aCC-BY-NC-ND 4.0 International license. (which was not certified by peer review) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity. It is made bioRxiv preprint doi: https://doi.org/10.1101/2024.08.26.609769; this version posted June 23, 2025. The copyright holder for this preprint levels and how they influence neighboring plants, especially in the context of subsequent drought. We characterized metagenomes of six prairie soils spanning a steep precipitation gradient in Kansas, USA. By statistically controlling for variation in soil porosity and elemental profiles, we identified bacterial taxa and functional gene categories associated with precipitation. This microbial precipitation legacy persisted through a 5-month-long experimental drought and mitigated the negative physiological effects of acute drought for a wild grass species that is native to the precipitation gradient, but not for the domesticated crop species maize. In particular, microbiota with a low-precipitation legacy altered transcription of a subset of host genes that mediate transpiration and intrinsic water use efficiency during drought. Our results show how long-term exposure to water stress alters soil microbial communities with consequences for the drought responses of neighboring plants. 

Abstract Both chronic and acute drought alter the composition and physiology of soil microbiota by selecting for functional traits that preserve fitness in dry conditions. Currently, little is known about how the resulting precipitation legacy effects manifest at the molecular and physiological levels and how they influence neighboring plants, especially in the context of subsequent drought. We characterized metagenomes of six prairie soils spanning a steep precipitation gradient in Kansas, USA. By statistically controlling for variation in soil porosity and elemental profiles, we identified bacterial taxa and functional gene categories associated with precipitation. This microbial precipitation legacy persisted through a 5-month-long experimental drought and mitigated the negative physiological effects of acute drought for a wild grass species that is native to the precipitation gradient, but not for the domesticated crop species maize. In particular, microbiota with a low-precipitation legacy altered transcription of a subset of host genes that mediate transpiration and intrinsic water use efficiency during drought. Our results show how long-term exposure to water stress alters soil microbial communities with consequences for the drought responses of neighboring plants. 

Abstract Among promising applications of metal‐halide perovskite, the most research progress is made for perovskite solar cells (PSCs). Data from myriads of research work enables leveraging machine learning (ML) to significantly expedite material and device optimization as well as potentially design novel configurations. This paper represents one of the first efforts in providing open‐source ML tools developed utilizing the Perovskite Database Project (PDP), the most comprehensive open‐source PSC database to date with over 43 000 entries from published literature. Three ML model architectures with short‐circuit current density (J_sc) as a target are trained exploiting the PDP. Using the XGBoost architecture, a root mean squared error (RMSE) of 3.58 , R²of 0.35 and a mean absolute percentage error (MAPE) of 9.49% are achieved. This performance is comparable to results reported in literature, and through further investigation can likely be improved. To overcome challenges with manual database creation, an open‐source data cleaning pipeline is created for PDP data. Through the creation of these tools, which have been published on GitHub, this research aims to make ML available to aid the design for PSC while showing the already promising performance achieved. The tools can be adapted for other applications, such as perovskite light‐emitting diodes (PeLEDs), if a sufficient database is available. 

Abstract A potential strategy to mitigate oxidative damage in plants is to increase the abundance of antioxidants, such as ascorbate (i.e. vitamin C). In Arabidopsis (A. thaliana), a rate-limiting step in ascorbate biosynthesis is a phosphorylase encoded by Vitamin C Defective 2 (VTC2). To specifically overexpress VTC2 (VTC2 OE) in pollen, the coding region was expressed using a promoter from a gene with ∼150-fold higher expression in pollen, leading to pollen grains with an eight-fold increased VTC2 mRNA. VTC2 OE resulted in a near-sterile phenotype with a 50-fold decrease in pollen transmission efficiency and a five-fold reduction in the number of seeds per silique. In vitro assays revealed pollen grains were more prone to bursting (greater than two-fold) or produced shorter, morphologically abnormal pollen tubes. The inclusion of a genetically encoded Ca2+ reporter, mCherry-GCaMP6fast (CGf), revealed pollen tubes with altered tip-focused Ca2+ dynamics and increased bursting frequency during periods of oscillatory and arrested growth. Despite these phenotypes, VTC2 OE pollen failed to show expected increases in ascorbate or reductions in reactive oxygen species, as measured using a redox-sensitive dye or a roGFP2. However, mRNA expression analyses revealed greater than two-fold reductions in mRNA encoding two enzymes critical to biosynthetic pathways related to cell walls or glyco-modifications of lipids and proteins: GDP-d-mannose pyrophosphorylase (GMP) and GDP-d-mannose 3′,5′ epimerase (GME). These results support a model in which the near-sterile defects resulting from VTC2 OE in pollen are associated with feedback mechanisms that can alter one or more signaling or metabolic pathways critical to pollen tube growth and fertility. 

ABSTRACT With the advent of ALMA, it is now possible to observationally constrain how discs form around deeply embedded protostars. In particular, the recent ALMA C3H2 line observations of the nearby protostar L1527 have been interpreted as evidence for the so-called ‘centrifugal barrier,’ where the protostellar envelope infall is gradually decelerated to a stop by the centrifugal force in a region of super-Keplerian rotation. To test the concept of centrifugal barrier, which was originally based on angular momentum conserving-collapse of a rotating test particle around a fixed point mass, we carry out simple axisymmetric hydrodynamic simulations of protostellar disc formation including a minimum set of ingredients: self-gravity, rotation, and a prescribed viscosity that enables the disc to accrete. We find that a super-Keplerian region can indeed exist when the viscosity is relatively large but, unlike the classic picture of centrifugal barrier, the infalling envelope material is not decelerated solely by the centrifugal force. The region has more specific angular momentum than its surrounding envelope material, which points to an origin in outward angular momentum transport in the disc (subject to the constraint of disc expansion by the infalling envelope), rather than the spin-up of the envelope material envisioned in the classic picture as it falls closer to the centre in order to conserve angular momentum. For smaller viscosities, the super-Keplerian rotation is weaker or non-existing. We conclude that, despite the existence of super-Keplerian rotation in some parameter regime, the classic picture of centrifugal barrier is not supported by our simulations. 

Abstract A new, more comprehensive model of gas–grain chemistry in hot molecular cores is presented, in which nondiffusive reaction processes on dust-grain surfaces and in ice mantles are implemented alongside traditional diffusive surface/bulk-ice chemistry. We build on our nondiffusive treatments used for chemistry in cold sources, adopting a standard collapse/warm-up physical model for hot cores. A number of other new chemical model inputs and treatments are also explored in depth, culminating in a final model that demonstrates excellent agreement with gas-phase observational abundances for many molecules, including some (e.g., methoxymethanol) that could not be reproduced by conventional diffusive mechanisms. The observed ratios of structural isomers methyl formate, glycolaldehyde, and acetic acid are well reproduced by the models. The main temperature regimes in which various complex organic molecules (COMs) are formed are identified. Nondiffusive chemistry advances the production of many COMs to much earlier times and lower temperatures than in previous model implementations. Those species may form either as by-products of simple-ice production, or via early photochemistry within the ices while external UV photons can still penetrate. Cosmic ray-induced photochemistry is less important than in past models, although it affects some species strongly over long timescales. Another production regime occurs during the high-temperature desorption of solid water, whereby radicals trapped in the ice are released onto the grain/ice surface, where they rapidly react. Several recently proposed gas-phase COM-production mechanisms are also introduced, but they rarely dominate. New surface/ice reactions involving CH and CH₂are found to contribute substantially to the formation of certain COMs.