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Short‐wave infrared (SWIR) image sensors based on colloidal quantum dots (QDs) are characterized by low cost, small pixel pitch, and spectral tunability. Adoption of QD‐SWIR imagers is, however, hampered by a reliance on restricted elements such as Pb and Hg. Here, QD photodiodes, the central element of a QD image sensor, made from non‐restricted In(As,P) QDs that operate at wavelengths up to 1400 nm are demonstrated. Three different In(As,P) QD batches that are made using a scalable, one‐size‐one‐batch reaction and feature a band‐edge absorption at 1140, 1270, and 1400 nm are implemented. These QDs are post‐processed to obtain In(As,P) nanocolloids stabilized by short‐chain ligands, from which semiconducting films of n‐In(As,P) are formed through spincoating. For all three sizes, sandwiching such films between p‐NiO as the hole transport layer and Nb:TiO2 as the electron transport layer yields In(As,P) QD photodiodes that exhibit best internal quantum efficiencies at the QD band gap of 46±5% and are sensitive for SWIR light up to 1400 nm. A complete process flow to form photodiode stacks sensitive for short‐wave infrared (SWIR) light based on non‐restricted In(As,P) quantum dots (QDs) is proposed. Films made of semiconducting n‐In(As,P) QDs inks, formulated through apolar/polar QD phase transfer, form a rectifying junction with p‐NiO that is photosensitive beyond 1400 nm. This result highlights the prospect of printable SWIR opto‐electronics based on InAs QDs.

Modern electronic and photonic devices rely on single-crystalline thin film semiconductors for high performance and reproducibility. The emerging halide perovskites have extraordinary electronic and photonic properties and can be synthesized via low cost solution-based methods. They have been used in a variety of devices with performance approaching or over the devices based on conventional materials. However, their solution based growth method is intrinsically challenge to grow large scale single-crystalline thin film due to the random nucleation and isotropous growth of the crystal. Here, we report the growth of centimeter-scale perovskite single-crystalline thin films by controlling the nucleation density and growth rate of the crystal under a spatially confined growth condition. The hydrophobic treatment on substrates inhibits nucleation and accelerates the growth of single-crystalline thin film, providing enough space for initial nucleus growing up quickly without touching each other. Single-crystalline perovskite thin-film with an aspect ratio of 1000 (1 cm in side length, 10 μm in thickness) has been successfully grown. The low trap density and the high mobility of the as-grown thin film show a high crystallinity. The photodetector based on the perovskite thin film has achieved a gain ~ 104, benefitting from the short transit time of the carries due to the high mobility and thin thickness of the active layer. Our work opens up a new route to grow large scale perovskite single-crystalline thin films, providing a platform to develop high- performance devices.

High-resolution TEM (HRTEM) is a powerful tool for structure characterization. However, methylammonium lead iodide (MAPbI3) perovskite is highly sensitive to electron beams and easily decomposes into lead iodide (PbI2). Misidentifications, such as PbI2 being incorrectly labeled as perovskite, are widely present in HRTEM characterization and would negatively affect the development of perovskite research field. Here misidentifications in MAPbI3 perovskite are summarized, classified, and corrected based on low-dose imaging and electron diffraction (ED) simulations. Corresponding crystallographic parameters of intrinsic tetragonal MAPbI3 and the confusable hexagonal PbI2 are presented unambiguously. Finally, the method of proper phase identification and some strategies to control the radiation damage in HRTEM are provided. This warning paves the way to avoid future misinterpretations in HRTEM characterization of perovskite and other electron beam-sensitive materials.

Defects are generally regarded to have negative impacts on carrier recombination, charge transport, and ion migration in materials, which thus lower the efficiency, speed, and stability of optoelectronic devices. Meanwhile, lots of efforts which focused on minimizing defects have greatly improved the performances of devices. Then, can defects be positive in optoelectronic devices? Herein, relying on in‐depth understanding of defect‐associated effects in semiconductors, trapping of photo‐generated carriers by defects is applied to enlarge photoconductive gain in photodetection. Therefore, the record photoconductive gain, gain‐bandwidth product, and detection limit are achieved in this photodetector. Exceeding the general concept that defects are harmful, a new view that the defects can be positive in photodetection is identified, which may guide to design high‐performance photodetectors. Relying on in‐depth understanding of defect‐associated effects in semiconductors, trapping of photo‐generated carriers by defects is applied to enlarge photoconductive and the record performances are achieved in this photodetector. Exceeding the general concept that defects are harmful, a new view that defects are positive in optoelectronics is identified, which will guide us to design high‐performance devices in the future.

Clearly, (1Ē2), (112) planes exist in the electron diffraction pattern. [...]П2), (112) planes are also present in HRTEM images under low electron dose2, selected-area electron diffraction (SAED)3,4 and X-ray diffraction (XRD)5-7 characterizations. Owing to lack of the corresponding in situ high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) image in the original paper, it is impossible to prove that the higher-contrast spots are PbS quantum dots rather than PbI2 particles. If possible, it would also be better if they compared the particle size and size distribution of colloidal quantum dots and quantum dots in perovskite in the original paper. [...]a low dose10-15 and low temperature2,13 can reduce the damage of electron-beam irradiation to perovskite, and may help to obtain the real structure of the quantum dots in perovskite solids.

Sample preparation is significantly important to the high-resolution transmission electron microscopy (HRTEM) characterization of nanomaterials. However, many general organic solvents can dissolve the necessary organic polymer support layer in TEM grid, which causes it difficult to obtain high-quality samples of oil-soluble nanomaterials. In this study, a new sample preparation method for oil-soluble nanomaterials has been developed by using the sublimable material as a transition layer. Experiments also show that there is no damage to TEM grids and high-quality HRTEM images can be obtained via this method. This approach paves the way to applicable HRTEM sample preparation of oil-soluble nanomaterials.

Arteriosclerosis obliterans (ASO) is a major cause of adult limb loss worldwide. Autophagy of vascular endothelial cell (VEC) contributes to the ASO progression. However, the molecular mechanism that controls VEC autophagy remains unclear. In this study, we aimed to explore the role of the GRB2 associated binding protein 1 (GAB1) in regulating VEC autophagy. In vivo and in vitro studies were applied to determine the loss of adapt protein GAB1 in association with ASO progression. Histological GAB1 expression was measured in sclerotic vascular intima and normal vascular intima. Gain- and loss-of-function of GAB1 were applied in VEC to determine the effect and potential downstream signaling of GAB1. The autophagy repressor p62 was significantly downregulated in ASO intima as compared to that in healthy donor (0.80 vs. 0.20, t = 6.43, P < 0.05). The expression level of GAB1 mRNA (1.00 vs. 0.24, t = 7.41, P < 0.05) and protein (0.72 vs. 0.21, t = 5.97, P < 0.05) was significantly decreased in ASO group as compared with the control group. Loss of GAB1 led to a remarkable decrease in LC3II (1.19 vs. 0.68, t = 5.99, P < 0.05), whereas overexpression of GAB1 significantly led to a decrease in LC3II level (0.41 vs. 0.93, t = 7.12, P < 0.05). Phosphorylation levels of JNK and p38 were significantly associated with gain- and loss-of-function of GAB1 protein. Loss of GAB1 promotes VEC autophagy which is associated with ASO. GAB1 and its downstream signaling might be potential therapeutic targets for ASO treatment.

Background The aim of this study was to examine the associations of tea consumption with the serum uric acid (SUA) level, hyperuricemia (HU) and the risk of gout. Methods A comprehensive literature search up to June 2016, using PUBMED and EMBASE databases, was conducted to identify the relevant observational studies that examined the associations of tea consumption with the SUA level, HU and the risk of gout. Results A total of fifteen observational studies were included in this study, and nine studies were extracted for meta-analysis. For the SUA level, seven studies were included. According to the combined weighted mean difference (WMD), there was no significant difference between the highest and the lowest tea intake category in terms of the SUA level (WMD = 7.41 μmol/L, 95%CI: −2.34 to 17.15; P =  0.136). In subgroup analysis including three studies, green tea consumption was positively associated with the SUA level (WMD = 17.20 μmol/L, 95%CI: 7.00 to 27.40; P =  0.01). For the prevalence of HU, five studies were included. The overall multi-variable adjusted odds ratio (OR) for the highest versus the lowest category of tea consumption was 0.98 (95%CI: 0.77 to 1.24; P =  0.839). For the risk of gout, two prospective cohort studies showed that there was no relationship between tea consumption and the risk of gout in males and females, respectively. Conclusion The current evidences suggest that tea consumption does not seem to be associated with the SUA level, HU and the risk of gout. However, due to the limited number of studies, green tea consumption might be positively associated with the SUA level. More well-designed prospective cohort studies are needed to elaborate these issues further.

Optically levitated nanodumbbells in vacuum are excellent candidates for thermodynamics, macroscopic quantum mechanics, precision measurements and quantum sensing. Silica (SiO 2 ) material, with extremely low absorption of near-infrared light and super mechanical strength, has been the most potential material for optically levitated systems. Here we synthesize high-purity solid SiO 2 nanodumbbells via Stöber method by introducing acetone for the induced aggregation of SiO 2 nanospheres. The nanodumbbells show high uniformity and their sizes are tunable. Previous experimental results demonstrated that the synthetic nanodumbbells can be applied in GHz nanomechanical rotors and can withstand the tensile strength of over 13 GPa. This work supports batch production and high yield of SiO 2 nanodumbbells, which engineers a new material platform to advance levitated optomechanics.

Background and aims Nitrogen (N) deposition usually has adverse effects on various ecosystems. Farmland intercropping is a well-known planting model and agroecosystem with multiple benefits. However, research on N deposition in farmland, especially for intercropping systems remains limited. Methods Field experiments were conducted in three seasons to examine the effects of rice monocropping and rice-water mimosa ( Neptunia oleracea Lour.) intercropping systems on rice growth and soil properties under N deposition. The simulated N deposition rate was set at two levels, which included low N (LN) deposition at a rate of 40 kg·ha −1 ·yr −1 N and high N (HN) deposition at a rate of 120 kg·ha −1 ·yr −1 N, which were applied in addition to 180 kg·ha −1 ·yr −1 N fertilization during the overall growth period of rice. Results With increasing N deposition, rice plant height, average root diameter and water mimosa yield, above-ground dry weight decreased in the monocropping treatment. Meanwhile, water mimosa yield, above-ground dry weight, and all of the indices of root morphology in 2022 early season decreased with the increasing N deposition in the rice-water mimosa intercropping system. Contents of soil total manganese (Mn), total zinc (Zn), total calcium (Ca), and cellobiosidase activity also declined with increasing N deposition. However, the land equivalent ratio (LER) of the intercropping system was greater than 1 even under N deposition. In addition, compared with monocropping, intercropping increased dry weight of stem and leaves, average root diameter of rice, contents of soil total nitrogen, total phosphorous, total Mn, total Zn, total Ca and the activity of acid phosphatase, and also enhanced soil microbial biomass carbon (MBC), nitrogen (MBN) and phosphorus (MBP), gram-positive bacteria, gram-negative bacteria, fungi, bacteria, methane-oxidizing bacteria contents and fungi/bacteria ratio. Conclusion The experiment results suggest that N deposition caused negative impacts on rice farming system. However, rice and water mimosa intercropping systems can reduce the negative effects of N deposition (especially LN) on rice and soil. The findings demonstrate that this intercropping system is advantageous under N deposition (especially LN) than rice monocropping.