Strigolactones (SLs) are a group of newly identified plant hormones that control plant shoot branching. SL signalling requires the hormone-dependent interaction of DWARF 14 (D14), a probable candidate SL receptor, with DWARF 3 (D3), an F-box component of the Skp–Cullin–F-box (SCF) E3 ubiquitin ligase complex. Here we report the characterization of a dominant SL-insensitive rice (Oryza sativa) mutant dwarf 53 (d53) and the cloning of D53, which encodes a substrate of the SCFD3 ubiquitination complex and functions as a repressor of SL signalling. Treatments with GR24, a synthetic SL analogue, cause D53 degradation via the proteasome in a manner that requires D14 and the SCFD3 ubiquitin ligase, whereas the dominant form of D53 is resistant to SL-mediated degradation. Moreover, D53 can interact with transcriptional co-repressors known as TOPLESS-RELATED PROTEINS. Our results suggest a model of SL signalling that involves SL-dependent degradation of the D53 repressor mediated by the D14–D3 complex.

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There has recently been a dramatic renewal of interest in hadron spectroscopy and charm physics. This renaissance has been driven in part by the discovery of a plethora of charmonium-like XYZ states at BESIII and B factories, and the observation of an intriguing proton-antiproton threshold enhancement and the possibly related X(1835) meson state at BESIII, as well as the threshold measurements of charm mesons and charm baryons. We present a detailed survey of the important topics in tau-charm physics and hadron physics that can be further explored at BESIII during the remaining operation period of BEPCII. This survey will help in the optimization of the data-taking plan over the coming years, and provides physics motivation for the possible upgrade of BEPCII to higher luminosity.

The oxygen evolution reaction (OER) is a key reaction for many electrochemical devices. To date, many OER electrocatalysts function well in alkaline media, but exhibit poor performances in neutral and acidic media, especially the acidic stability. Herein, sodium‐decorated amorphous/crystalline RuO2 with rich oxygen vacancies (a/c‐RuO2) was developed as a pH‐universal OER electrocatalyst. The a/c‐RuO2 shows remarkable resistance to acid corrosion and oxidation during OER, which leads to an extremely high catalytic stability, as confirmed by a negligible overpotential increase after continuously catalyzing OER for 60 h at pH=1. Besides, a/c‐RuO2 also exhibits superior OER activities to commercial RuO2 and most reported OER catalysts under all pH conditions. Theoretical calculations indicated that the introduction of Na dopant and oxygen vacancy in RuO2 weakens the adsorption strength of the OER intermediates by engineering the d‐band center, thereby lowering the energy barrier for OER.

There are currently some problems in the field of chemical synthesis, such as environmental impact, energy loss, and safety, that need to be tackled urgently. An interdisciplinary approach, based on different backgrounds, may succeed in solving these problems. Organisms can be chosen as potential platforms for materials fabrication, since biosystems are natural and highly efficient. Here, an example of how to solve some of these chemical problems through biology, namely, through a novel biological strategy of coupling intracellular irrelated biochemical reactions for controllable synthesis of multicolor CdSe quantum dots (QDs) using living yeast cells as a biosynthesizer, is demonstrated. The unique fluorescence properties of CdSe QDs can be utilized to directly and visually judge the biosynthesis phase to fully demonstrate this strategy. By such a method, CdSe QDs, emitting at a variety of single fluorescence wavelengths, can be intracellularly, controllably synthesized at just 30°C instead of at 300°C with combustible, explosive, and toxic organic reagents. This green biosynthetic route is a novel strategy of coupling, with biochemical reactions taking place irrelatedly, both in time and space. It involves a remarkable decrease in reaction temperature, from around 300 °C to 30 °C and excellent color controllability of CdSe photoluminescence. It is well known that to control the size of nanocrystals is a mojor challenge in the biosynthesis of high‐quality nanomaterials. The present work demonstrates clearly that biological systems can be creatively utilized to realize controllable unnatural biosynthesis that normally does not exist, offering new insights for sustainable chemistry.

A rapid and sensitive method is crucial for nucleic acid detection. Recently, RNA-guided CRISPR/Cas12a nuclease-based methods present great promise for nucleic acid detection. In the present methods, however, DNA amplification and subsequent Cas12a cleavage is separated and the whole process takes as long as 2 h. Most importantly, the uncapping operation increases the risk of aerosol contamination. In this study, we propose a CRISPR/Cas12a-based method named “Cas12aVDet” for rapid nucleic acid detection. By integrating recombinase polymerase amplification (RPA) with Cas12a cleavage in a single reaction system, the detection can be accomplished in 30 min and uncapping contamination can be avoided. The detection signal can be observed by the naked eye under blue light. This method could detect DNA at single molecule level and demonstrated 100% accuracy for mycoplasma contamination detection, presenting great potential for a variety of nucleic acid detection applications.

Label and label-free methods to image carbon-based nanomaterials exist. However, label-based approaches are limited by the risk of tag detachment over time, and label-free spectroscopic methods have slow imaging speeds, weak photoluminescence signals and strong backgrounds. Here, we present a label-free mass spectrometry imaging method to detect carbon nanotubes, graphene oxide and carbon nanodots in mice. The large molecular weights of nanoparticles are difficult to detect using conventional mass spectrometers, but our method overcomes this problem by using the intrinsic carbon cluster fingerprint signal of the nanomaterials. We mapped and quantified the sub-organ distribution of the nanomaterials in mice. Our results showed that most carbon nanotubes and nanodots were found in the outer parenchyma of the kidney, and all three materials were seen in the red pulp of the spleen. The highest concentrations of nanotubes in the spleen were found within the marginal zone.

We report the synthesis and electrochemical performance of one-dimensional TiO 2 −graphene composite nanofibers (TiO 2 −G nanofibers) by a simple electrospinning technique for the first time. Structural and morphological properties were characterized by various techniques, such as Xray diffraction, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy, and BET surface area analysis. Lithium insertion properties were evaluated by both galvanostatic and potentiostatic modes in half-cell configurations. Cyclic voltammetric study reveals the Li-insertion/extraction by a two-phase reaction mechanism that is supported by galvanostatic charge−discharge profiles. Li/TiO 2 −G half-cells showed an initial discharge capacity of 260 mA h g −1 at current density of 33 mA g −1 . Further, Li/TiO 2 −G cell retained 84% of reversible capacity after 300 cycles at a current density of 150 mA g −1 , which is 25% higher than bare TiO 2 nanofibers under the same test conditions. The cell also exhibits promising high rate behavior with a discharge capacity of 71 mA h g −1 at a current density of 1.8 A g −1 .