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Heterotrophic bacteria and archaea (“heteroprokaryotes”) drive global carbon cycling, but how to quantitatively organize their functional complexity remains unclear. We generated a global-scale understanding of marine heteroprokaryotic functional biogeography by synthesizing genetic sequencing data with a mechanistic marine ecosystem model. We incorporated heteroprokaryotic diversity into the trait-based model along two axes: substrate lability and growth strategy. Using genetic sequences along three ocean transects, we compiled 21 heteroprokaryotic guilds and estimated their degree of optimization for rapid growth (copiotrophy). Data and model consistency indicated that gradients in grazing and substrate lability predominantly set biogeographical patterns, and we identified deep-ocean “slow copiotrophs” whose ecological interactions control the surface accumulation of dissolved organic carbon. 

Establishing a nonzero measurement of the electron Electric Dipole Moment (eEDM) has long been a fundamental pursuit in atomic, molecular and optical physics, offering possible insights into new physics beyond the Standard Model. In this regard, lead monofluoride (PbF) has emerged as a potential candidate for measuring eEDM primarily due to its suitable properties such as the strong internal effective electric field, and eEDM-sensitive ground state with large Ω-doubling and small magnetic g factor. In the present work, we realized the production of a buffer-gas-cooled PbF molecular beam and characterized its high-resolution spectroscopy in the B 2Σ+(υ’=0) ← X1 2Π1/2(υ = 0) transition, including both direct absorption and laser-induced fluorescence spectroscopy. A highly concentrated beam of PbF molecules is obtained with a central forward velocity of 223 ± 17 m/s, while 81, 66 and 24 hyperfine-structure-resolved spectral lines with a frequency accuracy of 40 MHz have been assigned respectively for 208PbF, 207PbF and 206PbF isotopologues. The hyperfine constants due to the 19F nucleus (A∥ and A⊥) of the B state are reported for the first time, and those of the 207Pb nucleus have been also updated. Such a cryogenic molecular beam of PbF in association with its hyperfine-structure-resolved spectral atlas of the B 2Σ+(υ’=0) ← X1 2Π1/2(υ = 0) transition will be essential in developing sensitive detection schemes towards the eEDM measurement. 

Abstract Electrically driven light‐emitting diodes (ED LEDs) based on 3D metal halide perovskites have seen remarkable advancements during the past decade. However, the highest‐performing devices are largely based on lead‐containing 3D perovskites, presenting two key challenges – toxicity and stability – that must be addressed for commercialization. Reducing structural dimensionality and incorporating non‐lead metals present promising pathways to address these issues. Although research on ED LEDs based on low‐dimensional, lead‐free metal halides (LD LFMHs) is growing, their performance still significantly lags behind that of 3D lead halide perovskites. This review seeks to deliver a comprehensive overview of ED LEDs based on LD LFMHs, covering a brief history of their development, methods for material synthesis, luminescence mechanisms, and applications in electroluminescent devices. It also examines current challenges and proposes practical strategies to enhance device performance, with the goal of inspiring further progress in the field. 

Chemotherapy remains the standard treatment for triple‐negative breast cancer (TNBC); however, chemoresistance compromises its efficacy. The RNA‐binding protein Hu antigen R (HuR) could be a potential therapeutic target to enhance the chemotherapy efficacy. HuR is known to mainly stabilize its target mRNAs, and/or promote the translation of encoded proteins, which are implicated in multiple cancer hallmarks, including chemoresistance. In this study, a docetaxel‐resistant cell subline (231‐TR) was established from the human TNBC cell line MDA‐MB‐231. Both the parental and resistant cell lines exhibited similar sensitivity to the small molecule functional inhibitor of HuR, KH‐3. Docetaxel and KH‐3 combination therapy synergistically inhibited cell proliferation in TNBC cells and tumor growth in three animal models. KH‐3 downregulated the expression levels of HuR targets (e.g., β‐Catenin and BCL2) in a time‐ and dose‐dependent manner. Moreover, KH‐3 restored docetaxel's effects on activating Caspase‐3 and cleaving PARP in 231‐TR cells, induced apoptotic cell death, and caused S‐phase cell cycle arrest. Together, our findings suggest that HuR is a critical mediator of docetaxel resistance and provide a rationale for combining HuR inhibitors and chemotherapeutic agents to enhance chemotherapy efficacy. 

The synthesis of a low-molecular weight, neutral, porphyrin meso-tetra(dioxan-2-yl)porphyrin of significant solubility in aqueous solution is described using 4 × 1 or 2 + 2-type approaches. The key intermediate dioxan-2-carbaldehyde is accessible in either racemic or in stereo-pure forms from commercially available starting materials in three steps, allowing also the preparation of chiral porphyrins. 

Metal-halide perovskites, in particular their nanocrystal forms, have emerged as a new generation of light-emitting materials with exceptional optical properties, including narrow emissions covering the whole visible region with high photoluminescence quantum efficiencies of up to near-unity. Remarkable progress has been achieved over the last few years in the areas of materials development and device integration. A variety of synthetic approaches have been established to precisely control the compositions and microstructures of metal-halide perovskite nanocrystals (NCs) with tunable bandgaps and emission colors. The use of metal-halide perovskite NCs as active materials for optoelectronic devices has been extensively explored. Here, we provide a brief overview of recent advances in the development and application of metal-halide perovskite NCs. From color tuning via ion exchange and manipulation of quantum size effects, to stability enhancement via surface passivation, new chemistry for materials development is discussed. In addition, processes in optoelectronic devices based on metal-halide perovskite NCs, in particular, light-emitting diodes and radiation detectors, will be introduced. Opportunities for future research in metal-halide perovskite NCs are provided as well. 

Abstract Scintillation based X-ray detection has received great attention for its application in a wide range of areas from security to healthcare. Here, we report highly efficient X-ray scintillators with state-of-the-art performance based on an organic metal halide, ethylenebis-triphenylphosphonium manganese (II) bromide ((C₃₈H₃₄P₂)MnBr₄), which can be prepared using a facile solution growth method at room temperature to form inch sized single crystals. This zero-dimensional organic metal halide hybrid exhibits green emission peaked at 517 nm with a photoluminescence quantum efficiency of ~ 95%. Its X-ray scintillation properties are characterized with an excellent linear response to X-ray dose rate, a high light yield of ~ 80,000 photon MeV⁻¹, and a low detection limit of 72.8 nGy s⁻¹. X-ray imaging tests show that scintillators based on (C₃₈H₃₄P₂)MnBr₄powders provide an excellent visualization tool for X-ray radiography, and high resolution flexible scintillators can be fabricated by blending (C₃₈H₃₄P₂)MnBr₄powders with polydimethylsiloxane.