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The clinical application of photodynamic therapy (PDT) is limited by oxygen‐dependence and side effects caused by photosensitizer residues. Photoinitiators based on the H‐abstraction reaction can address these challenges because they can generate alkyl radical‐killing cells independently of oxygen and undergo rapid bleaching following H‐abstraction. Nonetheless, the development of photoinitiators for PDT has been impeded by the absence of effective design strategies. Herein, we have developed aryl‐ketone substituted cyanine (ACy−R), the first red‐light triggered H‐abstraction photoinitiators for hypoxic cancer therapy. These ACy−R molecules inherited the near‐infrared absorption of cyanine dye, and aryl‐ketone modification imparted H‐abstraction capability. Experimental and quantum calculations revealed that modifying the electron‐withdrawing groups of the aryl (e.g. ACy‐5F) improved the contribution of the O atom to the photon excitation process promoting intersystem crossing and H‐abstraction ability. Particularly, ACy‐5F rapidly penetrated cells and enriched in the endoplasmic reticulum. Even under severe hypoxia, ACy‐5F initiated red‐light induced H‐abstraction with intracellular biomolecules, inducing necroptosis and ferroptosis. Moreover, ACy‐5F was degraded after H‐abstraction, thus avoiding the side effects of long‐term phototoxicity after therapy. This study not only provides a crucial molecular tool for hypoxic tumors therapy, but also presents a promising strategy for the development of multifunctional photosensitizers and photoinitiators. [ABSTRACT FROM AUTHOR]

Background: Foot‐and‐mouth disease virus (FMDV) is an important pathogen of the MicroRNA virus family. Infection of livestock can cause physical weakness, weight loss, reduced milk production, and a significant reduction in productivity for an extended period. It also causes a high mortality rate in young animals, seriously affecting livestock production. The host range of FMDV is mainly limited to cloven‐hoofed animals such as cattle and sheep, while odd‐toed ungulates such as horses and donkeys have natural resistance to FMDV. The mechanism underlying this resistance in odd‐toed ungulates remains unclear. Objective: This study aimed to analyze the differences between FMDV‐infected cattle and horses to provide valuable insights into the host‐FMDV interaction mechanisms, thereby contributing to the control of foot‐and‐mouth disease and promoting the development of the livestock industry. Methods: We observed the distribution of integrins, which help FMDV enter host cells, in the nasopharyngeal tissues of cattle and horses using immunohistochemistry. Then, we employed high‐throughput RNA sequencing (RNA‐Seq) to study the changes in host gene expression in the nasopharyngeal epithelial tissues of cattle and horses after FMDV infection. We performed enrichment analysis of GO and KEGG pathways after FMDV infection and validated related genes through qPCR. Results: The immunohistochemical results showed that both cattle and horses had four integrin receptors that could assist FMDV entry into host cells. The transcriptome analysis revealed that after FMDV infection, pro‐apoptotic genes such as caspase‐3 (CASP3) and cytochrome C (CYCS) were upregulated in cattle, while apoptosis‐inhibiting genes such as NAIP and BCL2A1 were downregulated. In contrast, the expression trend of related genes in horses was opposite to that in cattle. Additionally, autophagy‐related genes such as beclin 1, ATG101, ATG4B, ATG4A, ATG13, and BCL2A1 were downregulated in cattle after FMDV infection, indicating that cattle did not clear the virus through autophagy. However, key autophagy genes including ATG1, ATG3, ATG9, ATG12, and ATG16L1 were significantly upregulated in horses after viral infection. Conclusion: Both water buffaloes and Mongolian horses express integrin receptors that allow FMDV entry into cells. Therefore, the resistance of Mongolian horses to FMDV may result from more changes in intracellular mechanisms, including processes such as autophagy and apoptosis. Significant differences were observed between water buffaloes and Mongolian horses in these processes, suggesting that these processes influence FMDV replication and synthesis. [ABSTRACT FROM AUTHOR]

Controlling the interplay between relaxation and charge/energy transfer processes in the excited states of photocatalysts is crucial for the performance of artificial photosynthesis. Metal‐to‐ligand charge‐transfer triplet states (3MLCT*) of ruthenium(II) complexes are broadly implemented for photocatalysis, but an effective means of managing the triplets for enhanced photocatalysis has been lacking. Herein, We proposed a strategy to considerably prolong the triplet excited‐state lifetime by decorating a ruthenium(II) phosphine complex (RuP‐1) with pendent polyaromatic hydrocarbons (PAHs). Systematic studies demonstrate that in RuP‐4 decorated with anthracene, sub‐picosecond electron transfer from anthracene to 3MLCT* leads to a charge‐separated state that can mediate the formation of the intra‐ligand triplet state (3IL) of anthracene, resulting in an exceptionally long excited‐state up to several milliseconds. This triplet management strategy enables impressive photocatalytic reduction of CO2 to CO with a turnover number (TON) of 404, an optimized quantum yield of 43 % and 100 % selectivity, which is the highest reported performance for mononuclear photocatalysts without additional photosensitizers. RuP‐4 also catalyzes photochemical hydrogen generation under argon. This work opens up an avenue for regulating the excited‐state charge/energy flow for the development of long‐lived 3IL multi‐functional mononuclear photocatalysts to boost artificial photosynthesis. [ABSTRACT FROM AUTHOR]

Simple Summary: The BMPR1B and T/Brachyury genes are considered major genetic factors influencing sheep reproduction and tail bone number. In this study, we conducted an association analysis between nine mutations of the BMPR1B gene and the litter sizes of short-tailed Gobi sheep and larger-tailed Ujimqin sheep. We also compared the frequency of the favorable alleles of four mutations among Gobi short tail sheep, Ujimqin sheep, and Mongolia sheep. In addition, we confirmed that the frequency of tail-bone-number-related T alleles at position c.363G>T in the T gene was significantly higher in short-tailed Gobi sheep than larger-tailed Ujimqin sheep. The significant deposition of tail fat in sheep has a profound impact on the economic benefits of animal husbandry. Furthermore, increasing the litter size is a crucial means of enhancing economic benefits. The BMPR1B and T/Brachyury genes are considered major functional genes that could affect sheep litter size and tail bone number, respectively. In this study, we employed direct sequencing to identify specific mutations of the BMPR1B gene in Gobi short tail sheep and carried out genotyping using MassARRAY technology for each variant of both the BMPR1B and T genes. Significant associations were demonstrated between the c.687G>A mutation of BMPR1B and the litter size in both the Gobi short tail sheep and Ujimqin sheep breeds. Meanwhile, the g.30058882_30058873GCAGATTAAAIndel mutation was significantly associated with the litter size in Gobi short tail sheep. These findings may provide valuable genetic markers for expanding sheep litter size. In addition, we also confirmed that the frequency of tail-bone-number-related T alleles was significantly higher in Gobi short tail sheep than in longer-tailed Ujimqin sheep. [ABSTRACT FROM AUTHOR]

Decreasing perovskite nanocrystal size increases radiative recombination due to the quantum confinement effect, but also increases the Auger recombination rate which leads to carrier imbalance in the emitting layers of electroluminescent devices. Here, we overcome this trade‐off by increasing the exciton effective mass without affecting the size, which is realized through the trace Cd2+ doping of formamidinium lead bromide perovskite nanocrystals. We observe an ~2.7 times increase in the exciton binding energy benefiting from a slight distortion of the [BX6]4− octahedra caused by doping in the case of that the Auger recombination rate is almost unchanged. As a result, bright color‐saturated green emitting perovskite nanocrystals with a photoluminescence quantum yield of 96 % are obtained. Cd2+ doping also shifts up the energy levels of the nanocrystals, relative to the Fermi level so that heavily n‐doped emitters convert into only slightly n‐doped ones; this boosts the charge injection efficiency of the corresponding light‐emitting diodes. The light‐emitting devices based on those nanocrystals reached a high external quantum efficiency of 29.4 % corresponding to a current efficiency of 123 cd A−1, and showed dramatically improved device lifetime, with a narrow bandwidth of 22 nm and Commission Internationale de I'Eclairage coordinates of (0.20, 0.76) for color‐saturated green emission for the electroluminescence peak centered at 534 nm, thus being fully compliant with the latest standard for wide color gamut displays. [ABSTRACT FROM AUTHOR]

All‐inorganic metal halides with afterglow emission have attracted increasing attention due to their significantly longer afterglow duration and higher stability compared to their organic–inorganic hybrid counterparts. However, their afterglow colors have not yet reached the blue spectral region. Here, we report all‐inorganic copper‐doped Rb2AgBr3 single crystals with ultralong blue afterglow (>300 s) by modulating defect states through doping engineering. The introduction of copper(I) ions into Rb2AgBr3 facilitates the formation of bromine vacancies, thus increasing the density of trap states available for charge storage and enabling bright, persistent emission after ceasing the excitation. Moreover, cascade energy transfer between distinct emissive centers in the crystals results in ultra‐broadband photoluminescence, not only covering the whole white light with near‐unity quantum yield but also extending into the near‐infrared region. This 'cocktail' of exotic light‐emission properties, in conjunction with the excellent stability of copper‐doped Rb2AgBr3 crystals, allowed us to demonstrate their implementation to solid‐state lighting, night vision, and intelligent anti‐counterfeiting. [ABSTRACT FROM AUTHOR]

Emerging photovoltaic technologies continue to march forward with power conversion efficiencies of lead halide perovskite solar cells (PSCs) nearing 26%, perovskite-Si tandems now exceeding the single junction detailed balance limit of 33%, and organic solar cells (OSCs) showing efficiencies nearing 20%. Yang and Yang[16] use transient absorption spectroscopy to investigate the recombination dynamics of photocarriers in a multilayer indium selenide nanofilm, showing that exciton-exciton annihilation is inefficient in multilayers due to weaker Coulomb interactions. [Extracted from the article]

The properties of colloidal quantum-confined semiconductor nanocrystals (NCs), including zero-dimensional (0D) quantum dots, 1D nanorods, 2D nanoplatelets, and their heterostructures, can be tuned through their size, dimensionality, and material composition. In their photovoltaic and photocatalytic applications, a key step is to generate spatially separated and long-lived electrons and holes by interfacial charge transfer. These charge transfer properties have been extensively studied recently, which is the subject of this Review. The Review starts with a summary of the electronic structure and optical properties of 0D–2D nanocrystals, followed by the advances in wave function engineering, a novel way to control the spatial distribution of electrons and holes, through their size, dimension, and composition. It discusses the dependence of NC charge transfer on various parameters and the development of the Auger-assisted charge transfer model. Recent advances in understanding multiple exciton generation, decay, and dissociation are also discussed, with an emphasis on multiple carrier transfer. Finally, the applications of nanocrystal-based systems for photocatalysis are reviewed, focusing on the photodriven charge separation and recombination processes that dictate the function and performance of these materials. The Review ends with a summary and outlook of key remaining challenges and promising future directions in the field. [ABSTRACT FROM AUTHOR]

Colloidal semiconductor nanoplatelets (NPLs) have emerged as low‐cost and free‐standing alternates of traditional quantum wells. The giant heavy‐ and light‐hole splitting in NPLs allows for efficient optical spin injection. However, the electron spin lifetimes for prototypical CdSe NPLs are within a few picoseconds, likely limited by strong electron‐hole exchange in these quantum‐ and dielectric‐confined materials. Here how this hurdle can be overcome with engineered NPL‐heterostructures is demonstrated. By constructing type‐I CdSe/ZnS core/shell NPLs, dielectric screening inside the core is strongly enhanced, prolonging the electron spin polarization time (τesp) to over 30 ps (or 60 ps electron spin‐flip time). Alternatively, by growing type‐II CdSe/CdTe core/crown NPLs to spatially separate electron and hole wavefunctions, the electron‐hole exchange is strongly suppressed, resulting in τesp as long as 300 ps at room temperature. This study not only exemplifies how the well‐established synthetic chemistry of colloidal heterostructures can aid in spin dynamics control but also establishes the feasibility of room‐temperature coherent spin manipulation in colloidal NPLs. [ABSTRACT FROM AUTHOR]