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Metal halide perovskites offer ample opportunities to develop advanced optoelectronic devices. This work showcases that the integration of metal halide perovskites into metal oxide nanoshells with controllable interior cavities can enable water-vapor-responsive dual-mode switching of fluorescence and structural color. Through a ship-in-a-bottle method to introduce a controlled amount of CsPbBr3 into MnO2 nanoshells, we have designed CsPbBr3@MnO2 yolk-shell nanostructures, which can uptake a defined amount of water to exhibit rapid (less than 1 s) and reversible (≥100 cycles) responses in both fluorescence on-off and color change when exposed to dynamic water vapor. These responses originate from the water-triggered phase transformation of CsPbBr3 to CsPb2Br5 and the structural color change of the MnO2 shell. The altered electronic and bonding structure at the oxide-halide interface, rapid water accumulation in the yolk-shell cavity, and protective effect of the oxide shell facilitate the reversible transformations. The response characteristics of the yolk-shell nanostructures have been further demonstrated in fabricating patterned films capable of multiple fluorescence/structural color responses, highlighting their potential for applications in advanced anticounterfeiting and encryption.

Abstract: The diastereoselective trifluoromethylation of chiral α,β‐unsaturated N‐tert‐butanesulfinyl ketimines with Ruppert‐Prakash reagent (TMSCF3) has been attained, which provided a convenient and straightforward method for the asymmetric synthesis of structurally diverse α‐tertiary trifluoromethyl allylic amines in high yields and with excellent diastereoselectivities (dr up to > 99:1). The stereochemical outcome of the present diastereoselective trifluoromethylation of the α,β‐unsaturated N‐tert‐butanesulfinyl ketimines suggested that a cyclic six‐membered transition state is involved in the reaction, which is remarkably different from that of the trifluoromethylation of N‐tert‐butanesulfinyl aldimines. [ABSTRACT FROM AUTHOR]

High resolution laser-based angle-resolved photoemission measurements are carried out on Bi2Sr2CuO6+7δ super-conductor covering a wide doping range from heavily underdoped to heavily overdoped samples. Two obvious energy scales are identified in the nodal dispersions: one is the well-known 50-80 meV high energy kink and the other is <10meV low energy kink. The high energy kink increases monotonously in its energy scale with increasing doping and shows weak temperature dependence, while the low energy kink exhibits a non-monotonic doping dependence with its coupling strength enhanced sharply below TC. These systematic investigations on the doping and temperature dependence of these two energy scales favor electron-phonon interactions as their origin. They point to the importance in involving the electron-phonon coupling in understanding the physical properties and the superconductivity mechanism of high temperature cuprate superconductors. [ABSTRACT FROM AUTHOR]

A 67-year-old gentleman presented with a 1-day history of left foot pain. He had recently been discharged following a coronary artery bypass graft; during the admission, he had received an intravenous heparin infusion. Examination revealed black-purple discolouration of the first and second digits of the left foot with pitting oedema to the level of the knee. The posterior tibial and dorsalis pedis pulses were both shown to be patent. A new thrombocytopenia was noted. Ultrasound imaging revealed multiple deep vein thrombosis. The history of recent heparin exposure coupled with venous gangrene secondary to deep vein thrombosis was consistent with heparin-induced thrombocytopenia. He was treated acutely with intravenous danaparoid and later with warfarin. There was complete resolution of the venous gangrene at 1 month follow-up. [ABSTRACT FROM AUTHOR]

CuxBi2Se3 is a superconductor that is a potential candidate for topological superconductors. We report our laser-based angle-resolved photoemission measurement on the electronic structure of the CuxBi2Se3 superconductor, and a detailed magneto-resistance measurement in both normal and superconducting states. We find that the topological surface state of the pristine Bi2Se3 topological insulator remains robust after the Cu-intercalation, while the Dirac cone location moves downward due to electron doping. Detailed measurements on the magnetic field-dependence of the resistance in the superconducting state establishes an irreversibility line and gives a value of the upper critical field at zero temperature of ∼4000 Oe for the Cu0.3Bi2Se3 superconductor with a middle point Tc of 1.9K. The relation between the upper critical field Hc2 and temperature T is different from the usual scaling relation found in cuprates and in other kinds of superconductors. Small positive magneto-resistance is observed in Cu0.3Bi2Se3 superconductors up to room temperature. These observations provide useful information for further study of this possible candidate for topological superconductors. [ABSTRACT FROM AUTHOR]

The layered transition metal chalcogenides have been a fertile land in solid state physics for many decades. Various MX2-type transition metal dichalcogenides, such as WTe2, IrTe2, and MoS2, have triggered great attention recently, either for the discovery of novel phenomena or some extreme or exotic physical properties, or for their potential applications. PdTe2 is a superconductor in the class of transition metal dichalcogenides, and superconductivity is enhanced in its Cu-intercalated form, Cu0.05PdTe2. It is important to study the electronic structures of PdTe2 and its intercalated form in order to explore for new phenomena and physical properties and understand the related superconductivity enhancement mechanism. Here we report systematic high resolution angle-resolved photoemission (ARPES) studies on PdTe2 and Cu0.05PdTe2 single crystals, combined with the band structure calculations. We present in detail for the first time the complex multi-band Fermi surface topology and densely-arranged band structure of these compounds. By carefully examining the electronic structures of the two systems, we find that Cu-intercalation in PdTe2 results in electron-doping, which causes the band structure to shift downwards by nearly 16 meV in Cu0.05PdTe2. Our results lay a foundation for further exploration and investigation on PdTe2 and related superconductors. [ABSTRACT FROM AUTHOR]

Resonant inelastic X-ray scattering (RIXS) is an ideal X-ray spectroscopy method to push the combination of energy and time resolutions to the Fourier transform ultimate limit, because it is unaffected by the core-hole lifetime energy broadening. Also, in pump-probe experiments the interaction time is made very short by the same core-hole lifetime. RIXS is very photon hungry so it takes great advantage from high-repetition-rate pulsed X-ray sources like the European XFEL. The Heisenberg RIXS instrument is designed for RIXS experiments in the soft X-ray range with energy resolution approaching the Fourier and the Heisenberg limits. It is based on a spherical grating with variable line spacing and a position-sensitive 2D detector. Initially, two gratings were installed to adequately cover the whole photon energy range. With optimized spot size on the sample and small pixel detector the energy resolution can be better than 40 meV (90 meV) at any photon energy below 1000 eV with the high-resolution (high-transmission) grating. At the SCS instrument of the European XFEL the spectrometer can be easily positioned thanks to air pads on a high-quality floor, allowing the scattering angle to be continuously adjusted over the 65-145° range. It can be coupled to two different sample interaction chambers, one for liquid jets and one for solids, each state-of-the-art equipped and compatible for optical laser pumping in collinear geometry. The measured performances, in terms of energy resolution and count rate on the detector, closely match design expectations. The Heisenberg RIXS instrument has been open to public users since the summer of 2022., (open access.)

The Nanling Mountains is one of the sixteen biodiversity hotspots in China. It divides the central and southern regions of the country. This paper documents the diversity of flea beetles in the Nanling Mountains based on a comprehensive insect biodiversity survey from 2020 to 2022. Three new species of the genus Minota Kutschera, 1859 viz. M. cuiae Zhang, Ruan, Liang & Yang sp. nov. (Guangxi), M. maoer Zhang, Ruan, Liang & Yang sp. nov. (Guangxi), and M. bimaculata Zhang, Ruan, Liang & Yang sp. nov. (Jiangxi) from the Nanling Mountains are described and illustrated. A checklist and key to the Chinese Minota species are provided.

To systematically evaluate the clinical efficacy and safety of Compound Danshen Dripping Pills combined with conventional antihypertensive drugs in the treatment of hypertensive left ventricular hypertrophy. China National Knowledge Infrastructure(CNKI), Wanfang, VIP, PubMed, EMbase, Cochrane Library, Ovid and Web of Science databases were searched by computer to retrieve the randomized controlled trials(RCTs) of Compound Danshen Dripping Pills combined with conventional antihypertensive drugs in the treatment of hypertensive left ventricular hypertrophy from the establishment of databases to July 2020. After two researchers performed data retrieval, data extraction, and risk assessment of bias, they used RevMan 5.3 software for Meta-analysis. A total of 10 RCTs were included, with a total of 979 patients. Meta-analysis results showed that in terms of interventricular septal thickness(MD=-0.70, 95%CI[-1.15,-0.24], P=0.003), left ventricular posterior wall thickness(MD=-0.81, 95%CI[-1.41,-0.21], P=0.008), left ventricular mass index(MD=-8.75, 95%CI[-17.40,-0.10], P=0.05), systolic blood pressure(MD=-8.97, 95%CI[-13.46,-4.48], P&lt;0.000 1), diastolic blood pressure(MD=-5.87, 95%CI[-8.39,-3.34], P&lt;0.000 01) and left ventricular end-diastolic diameter(MD=-1.73, 95%CI[-2.38,-1.08], P&lt;0.000 01), Compound Danshen Dripping Pills combined with conventional antihypertensive drugs was superior to conventional antihypertensive drugs. In terms of left ventricular ejection fraction(MD=0.41, 95%CI[-0.74, 1.55], P=0.49), there was no statistical difference in treatment between the two groups. Because of the small amount of literatures included in the safety aspect, it is impossible to give an accurate conclusion. The GRADE score showed that the level of evidence was low and extremely low. The results show that the Compound Danshen Dripping Pills combined with conventional antihypertensive drugs may effectively improve the clinical efficacy for hypertensive ventricular hypertrophy, and the safety needs to be further explored. Due to the low quality of the included literatures, more high-quality RCTs are needed for verification.

In magnetic resonance imaging (MRI), Gibbs artifact is often introduced by the reconstruction involving only part of the k-space data. The current methods of Gibbs artifact reduction are generally based on the k-space data. In this paper, an image processing method based on inverse diffusion is proposed. This method is directly applied to the MR images, which can achieve the reduction of artifacts while enhancing the edge by the diffusion of pixel gray value. Experiments showed that the Gibbs artifact was effectively reduced and the valuable details of the images were maintained.