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Human eyes possess exceptional image-sensing characteristics such as an extremely wide field of view, high resolution and sensitivity with low aberration1. Biomimetic eyes with such characteristics are highly desirable, especially in robotics and visual prostheses. However, the spherical shape and the retina of the biological eye pose an enormous fabrication challenge for biomimetic devices2,3. Here we present an electrochemical eye with a hemispherical retina made of a high-density array of nanowires mimicking the photoreceptors on a human retina. The device design has a high degree of structural similarity to a human eye with the potential to achieve high imaging resolution when individual nanowires are electrically addressed. Additionally, we demonstrate the image-sensing function of our biomimetic device by reconstructing the optical patterns projected onto the device. This work may lead to biomimetic photosensing devices that could find use in a wide spectrum of technological applications.

High-photoluminescence quantum yield (PLQY) is required to reach optimal performance in solar cells, lasers, and light-emitting diodes (LEDs). Typically, PLQY can be increased by improving the material quality to reduce the nonradiative recombination rate. It is in principle equally effective to improve the optical design by nanostructuring a material to increase light out-coupling efficiency (OCE) and introduce quantum confinement, both of which can increase the radiative recombination rate. However, increased surface recombination typically minimizes nanostructure gains in PLQY. Here a template-guided vapor phase growth of CH3NH3PbI3 (MAPbI3) nanowire (NW) arrays with unprecedented control of NW diameter from the bulk (250 nm) to the quantum confined regime (5.7 nm) is demonstrated, while simultaneously providing a low surface recombination velocity of 18 cm s-1. This enables a 56-fold increase in the internal PLQY, from 0.81% to 45.1%, and a 2.3-fold increase in OCEy to increase the external PLQY by a factor of 130, from 0.33% up to 42.6%, exclusively using nanophotonic design.

Metal halide perovskite has emerged as a promising material for light-emitting diodes. In the past, the performance of devices has been improved mainly by optimizing the active and charge injection layers. However, the large refractive index difference among different materials limits the overall light extraction. Herein, we fabricate efficient methylammonium lead bromide light-emitting diodes on nanophotonic substrates with an optimal device external quantum efficiency of 17.5% which is around twice of the record for the planar device based on this material system. Furthermore, optical modelling shows that a high light extraction efficiency of 73.6% can be achieved as a result of a two-step light extraction process involving nanodome light couplers and nanowire optical antennas on the nanophotonic substrate. These results suggest that utilization of nanophotonic structures can be an effective approach to achieve high performance perovskite light-emitting diodes.

Objective: To investigate the risk factors for delayed healing of peptic ulcer in patients with upper gastrointestinal bleeding (UGIB), so as to provide evidences for clinical treatment. Methods: A total of consecutive 138 hospitalized patients with UGIB due to peptic ulcer from January 2012 to December 2021 were enrolled. The healing rate of peptic ulcer was determined under reexamination of gastroscopy after 1 week of treatment. The related indice were analyze with univariate analysis to determine possible influencing factors for peptic ulcer, including gender, age, body mass index (BMI), diabetes, history of taking steroid anti-inflammatory drugs (NSAIDS), smoking, drinking, Helicobacter pylori (Hp) infection, hemoglobin, serum albumin, ulcer location or Logistic regression analysis was performed to determine the independent risk factors. Results: Univariate analysis showed that age, levels of serum albumin, Forrest classification, the location and size of ulcers were associated with delayed healing of ulcers in patients with upper gastrointestinal bleeding (P

This study employed fiber and geopolymer to enhance the engineering performance of coarse-grained fillers. By conducting a series of comparative mechanical tests, the ideal mass mixing ratio design of geopolymer and fiber was investigated first. Then, the influence of rock block content on the mechanical properties of coarse-grained fillers stabilized with fiber and geopolymer was explored. The deformation damage characteristics of fiber- and geopolymer-stabilized coarse-grained fillers with different rock block contents were also discussed in the final test. The results show that the ideal mass mixing ratio of geopolymer for coarse-grained filler stabilization was 15% of dry fine-grained soil in weight and the ideal dosage and length of fiber was 0.4% of dry fine-grained soil in weight and 1.2 × 10−2 m. The compressive strength of fiber- and geopolymer-stabilized coarse-grained fillers shows a tendency to increase first, then decrease, and then re-increase with the increase in rock block contents. The best compressive strength and resistance to deformation were achieved when the rock block content was 30%. The failure mode of fiber- and geopolymer-stabilized coarse-grained fillers translated from shearing slip to vertical splitting as the rock block content increased. This study can provide a reference and support for the engineering application of coarse-grained fillers stabilized with fiber and geopolymer. [ABSTRACT FROM AUTHOR]

Solution processability is a prominent advantage for the commercial fabrication of perovskite solar cells (PSCs). However, ionic side reactions can cause perovskite solutions to age, which greatly limits the industrial prospects for reproducible production of PSCs. Herein, the mechanism of underlying halogen anion side reactions is elucidated and an effective scheme for managing halogen anions is proposed. The oxidation of halogen anions is the main factor of solution aging. The addition of iodine monobromide (IBr) stabilizes the precursor solution by promoting the reverse oxidation reaction. Meanwhile, IBr can manage the loss of halogen anion in perovskite layers, effectively reducing the defect density. Moreover, IBr can improve the crystallization process to prepare perovskite films with large‐sized grains and high crystallinity. As a result, the IBr‐based perovskite solution can be stored for 14 days, the optimal device efficiency (24.05% at 0.09 cm2) and long‐term operational stability are far superior to control samples. By this strategy, a large‐area perovskite solar module with an efficiency of 19.34% is fabricated on the 6 × 6 cm2 substrate. This study is dedicated to providing a strategy for managing halogen anions to inhibit solution aging and improve film quality. [ABSTRACT FROM AUTHOR]

Fluidic silty sand is often difficult to use directly in engineering construction because of its low strength and plasticity index. This study employed steel slag to replace part of the cement in silty sand stabilization to broaden the feasibility of resource recycling and to reduce the construction cost and carbon emissions in engineering practices. A series of indoor tests investigated the influences of the cement/steel slag ratio, initial water content, curing age, and temperature on the compressive strength of cement- and steel slag-stabilized fluidic silty sands (CSFSSs). Their stabilization mechanism was discussed via microstructural observation and spectral analysis. The results showed that the most economical cement/steel slag ratio could be 9:6, saving 40% of cement and not changing with the initial water content. The compressive strength of the CSFSSs decreased with the initial water content and increased rapidly and then slowly over the curing age. The curing temperature had a positive impact on their strength growth. The microstructure characteristics and spectral analysis showed that adding steel slag indeed affected the formation of gels in the cement-stabilized fluidic silty sands. This study could reference the application of CSFSSs in engineering practices. [ABSTRACT FROM AUTHOR]

1D metal halide perovskite (MHP) nanowires (NWs) have energized research interest owing to their unique characteristics; they are grain‐boundary‐free, efficiently transport axial carriers, in conjunction with strong radial spatial confinement. Herein, recent progress in the synthesis, integration, property characterization, and advanced optoelectronic applications of MHP NWs is systematically reviewed. The approaches to synthesize MHP NWs are mainly classified into solution‐phase and vapor‐phase methods, as well as the top‐down technique. Meanwhile, highly ordered patterns/templates‐assisted and surface‐guided alignment methods are utilized to integrate MHP NWs into NW arrays. The enhanced long‐term stability and superior optoelectronic properties of MHP NWs enable excellent optoelectronic device performance, where solar cells, photodetectors, image sensors, bionic eyes, light‐emitting diodes, resistive random‐access memories, and field‐effect transistors are mainly discussed. Finally, some perspectives for further direction of exploration to improve the device performance and path ways toward their practical applications are also provided. [ABSTRACT FROM AUTHOR]

Metamaterial absorbers have become a popular research direction due to their broad application prospects, such as in radar, infrared imaging, and solar cell fields. Usually, nanostructured metamaterials are associated with a large number of geometric parameters, and traditional simulation designs are time consuming. In this paper, we propose a framework for designing plasma metamaterial absorbers in both a forward prediction and inverse design composed of a primary prediction network (PPN) and an auxiliary prediction network (APN). The framework can build the relationship between the geometric parameters of metamaterials and their optical response (reflection spectra, absorption spectra) from a large number of training samples, thus solving the problem of time-consuming and case-by-case numerical simulations in traditional metamaterial design. This framework can not only improve forward prediction more accurately and efficiently but also inverse design metamaterial absorbers from a given required optical response. It was verified that it is also applicable to absorbers of different structures and materials. Our results show that it can be used in metamaterial absorbers, chiral metamaterials, metamaterial filters, and other fields. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to investigate the incidence of chromosome anomalies in different types of congenital gastrointestinal obstruction and assess pregnancy outcomes of fetuses with congenital gastrointestinal obstruction. Methods: A total of 64 cases with gastrointestinal obstruction between January 2014 and December 2020 were enrolled in this study. They were divided into three groups according to sonographic images. Group A: isolated upper gastrointestinal obstruction; Group B: isolated lower gastrointestinal obstruction; Group C: non-isolated gastrointestinal obstruction. The rate of chromosome anomalies in different groups was calculated. Pregnant women with amniocentesis were followed up by medical records and telephone. The follow-up included pregnancy outcomes and development of the live born infants. Result: From January 2014 to December 2020, there were 64 fetus with congenital gastrointestinal obstruction underwent chromosome microarray analysis(CMA), the overall detection rate of CMA testing was 14.1%(9/64). The detection rate of Group A, B and C were 16.2%, 0 and 25.0% respectively. 9 fetuses with abnormal CMA results were all terminated. Among 55 fetuses with normal chromosomes, 10(18.2%) fetuses were not found to have any gastrointestinal obstruction after birth. 17(30.9%) fetuses were diagnosed with gastrointestinal obstruction and underwent surgical treatment after birth, one of which had lower gastrointestinal obstruction combined with biliary obstruction and died due to liver cirrhosis. 11(20.0%) pregnancy were terminated due to multiple abnormalities. 5(9.1%) fetuses were intrauterine death. 3(5.5%) fetuses were neonatal deaths. 9(16.4%) fetuses were lost to follow-up. Conclusion: It is crucial to understand whether the gastrointestinal tract abnormality is isolated or associated to other findings. The risk of chromosomal abnormalities in fetuses with isolated lower gastrointestinal obstruction is lower than upper gastrointestinal obstruction. While genetic abnormalities excluded, a promising prognosis is expected for fetuses with congenital gastrointestinal obstruction. [ABSTRACT FROM AUTHOR]

Background: Genetic testing of UGT1A1 was used to facilitate the diagnosis of Gilbert syndrome, and analyze the distribution features of pathogenic variants in the Chinese population. Methods: DNA was extracted from whole blood samples of patients with unconjugated hyperbilirubinemia, and sequencing of the UGT1A1 gene was performed after PCR amplification. After alignment with reference sequences, the known pathogenic variants were identified, the variant spectrum was analyzed, and the pathogenicity of novel variants was predicted using online mutation prediction tools. Results: A total of 117 patients were confirmed with Gilbert syndrome by UGT1A1 genetic diagnosis, where the most common pathogenic variants included promoter A(TA)7TAA insertion and p.Gly71Arg missense variant. Following novel variants were also identified: p.Ala61Gly, p.Tyr67Phe, p.Leu166Alafs*16, p.Arg240Lys, p.Ser306Phe, p.Arg341Gln, and p.Glu424* variants. Conclusions: Genetic testing of UGT1A1 in clinical practices could facilitate confirming Gilbert syndrome and performing differential diagnosis. The pathogenic variant spectrum in the Chinese population was similar to other Asian populations. The novel pathogenic variants identified in this study require further investigation. [ABSTRACT FROM AUTHOR]

Purpose: Elevated serum ferritin (SF), also defined as hyperferritinemia, is commonly seen in patients with nonalcoholic fatty liver disease (NAFLD). However, the clinical significance of SF in NAFLD remains controversial. The aim of this study was to characterize the NAFLD patients with elevated SF and to explore the association of hyperferritinemia with the severity of NAFLD proved by liver biopsy in the Chinese population. Patients and Methods: A total of 136 NAFLD patients proved by liver biopsy were enrolled. The demographic, anthropometric, clinical historic, laboratory, and histological characteristics were compared between elevated and normal SF groups. The independent factors for elevated SF were determined using multivariate logistic regression analysis. Results: The median age and body mass index were 41.00 (33.00– 57.75) years and 28.28 (26.28– 31.34) kg/m2, respectively. Hyperferritinemia was detected in 57 (41.9%) patients. Patients in the elevated SF group presented with more severe lipo- and glucometabolic disorder, and higher aminotransferases compared to those in the normal SF group (p < 0.05). In terms of histopathology, elevated SF was associated with worse steatosis and a higher proportion of positive iron staining (p < 0.05). Multivariate logistic regression analysis identified homeostasis model assessment of insulin resistance (OR: 1.170, 95% CI: 1.036– 1.322, p = 0.012), alanine aminotransferase (OR: 1.012, 95% CI: 1.005– 1.019, p < 0.001), and positive Perl's staining (OR: 4.880, 95% CI: 2.072– 11.494, p < 0.001) as independent risk factors of hyperferritinemia. Conclusion: NAFLD patients with hyperferritinemia were characterized as more severe metabolic dysfunction and liver injury. More attention should be paid to the metabolism state of NAFLD patients with elevated SF. Hyperferritinemia was correlated to hepatic steatosis in Chinese NAFLD patients. [ABSTRACT FROM AUTHOR]

Ligand‐solvent engineering has been widely applied to improve the quality of perovskite films by forming intermediate films. However, there is an inconsistent understanding in the studies on the composition and mechanism of intermediate films formed by different ligand solvents, and the influence on perovskite film morphology is still elusive. Herein, the pure intermediate films (composed of pure crystal nucleus and amorphous precursor) are fabricated by the addition of ligand solvents with different coordination abilities. Notably, a single heterogeneous nucleation process is induced by the pure intermediate film, resulting in the formation of vertically arranged internal perovskite crystals with few horizontal boundaries, that improve charge transfer and device performance. Furthermore, the small and uniform crystals obtained by adding a ligand solvent with weak coordination ability result in smooth films and a smaller device current (Jsc = 22.74 mA cm−2, PCE = 19.58%). In contrast, the large and uneven crystals obtained by strong coordination ability lead to rough films and a larger device current (Jsc = 23.24 mA cm−2, PCE = 20.72%). This study is devoted to providing a significance reference for the fabrication of perovskite films with vertically arranged internal grains and superior surface textures. [ABSTRACT FROM AUTHOR]

The nucleation and crystallization processes within solution‐processed deposition is key for obtaining perovskite films with high quality. Herein, the synergistic effect of Cs+, ligand solvent (tetramethylene sulfoxide, TMSO), and methylammonium ions (MA+) on nucleation and crystallization procedures of preparing perovskites films is studied. The results reveal that producing α‐phase nuclei in the intermediate‐phase film (a perovskite film formed by removing the solvent before annealing) is the key factor for obtaining α‐phase‐pure perovskites, wherein Cs+ is necessary for reducing the formation energy of the α‐phase. In addition, the nonvolatile ligand (TMSO) is used to inhibit rapid nucleation, because it can form a stable intermediate phase. Furthermore, the introduction of the volatile MA+ cations compound (MACl) combined with Cs+ contributed to the direct formation of α‐phase nuclei in the intermediate‐phase film, and ion exchange (between FA+ and MA+) occurs during the subsequent annealing process, which leads to the formation of large‐grain perovskite film with good crystallinity. Maximum power conversion efficiencies of 22.08% and 16.88% are obtained via this strategy for a perovskite solar cell on a small area (active area: 0.09 cm2) and a perovskite solar module (aperture area: 12.92 cm2), respectively. [ABSTRACT FROM AUTHOR]

The fabrication of large area perovskite solar modules (PSMs) is attracting increasing attention. Traditionally, thin film solar modules are prepared by laser‐engraving several isolated lines to create a series of subcells. This process inevitably leads to an increase in series resistance when combining the subcells. Herein, a facile structure combining series and parallel cell connections is designed and developed for constructing PSMs. A champion power conversion efficiency (PCE) of 18.82% is achieved for perovskite composite modules with a designated area of 21.06 cm2. Furthermore, the PSMs can continue to operate even when parts of the device are shaded or broken. Because of the repeated structural arrangement, these modules may be suitable for fabrication on a broader scale for commercial applications. [ABSTRACT FROM AUTHOR]

Introduction and Aims. Bile acids play an essential role in the progression of nonalcoholic fatty liver disease (NAFLD). This study was aimed at investigating the association of the serum glycocholic acid- (GCA-) to-total bile acid (TBA) ratio with NAFLD in the general population. Materials and Methods. A total of 6708 subjects (2859 cases with NAFLD and 3849 controls) were enrolled in the development cohort and additional 1568 subjects (784 cases with NAFLD and 784 controls) in an independent validation cohort. Demographic characteristics and biochemical data were compared between subjects with NAFLD and controls. Multivariate logistic regression analysis was performed to determine the association of the GCA-to-TBA ratio with NAFLD. A novel model incorporating the GCA-to-TBA ratio was developed for screening NAFLD from the general population. Results. The serum TBA and GCA levels were significantly higher in subjects with NAFLD than in those without NAFLD (2.8 (2.0-4.2) μmol/L vs. 2.5 (1.8-3.7) μmol/L and 1.30 (1.10-1.53) μg/mL vs. 1.28 (1.08-1.50) μg/mL, respectively, all p ≤ 0.01), whereas the serum GCA-to-TBA ratio was significantly lower in subjects with NAFLD than in subjects without NAFLD (0.44 (0.33-0.60) vs. 0.48 (0.36-0.64), p ≤ 0.01). Logistic regression analysis showed that the GCA-to-TBA ratio was independently associated with NAFLD after adjustment for confounding factors (odds ratio: 0.81, 95% confidence interval (CI): 0.71-0.92, p ≤ 0.01). The area under the receiver operating characteristic curve of the novel developed GCA-to-TBA ratio score model in discriminating NAFLD was 0.84 (95% CI: 0.83-0.85) in the development cohort and was 0.91 (95% CI: 0.36-0.65) in the validation cohort. Conclusion. The serum GCA-to-TBA ratio is independently associated with NAFLD. A simple novel model incorporating the GCA-to-TBA ratio score has a good performance in discriminating NAFLD from the general population. [ABSTRACT FROM AUTHOR]

Multilayered photovoltaic absorbers have triggered widespread attention for their unique structure and properties. However, multilayered materials in the randomly oriented polycrystalline thin‐film lead to ineffective carrier transport and collection, which hinders the process of achieving high‐performance solar cells. Herein, this issue is tackled by producing the three‐dimensional (3D) heterojunction BiI3 nanosheets (NSs) solar cells, which embed vertically aligned monocrystalline BiI3 NSs into spiro‐OMeTAD. The preferred orientation of BiI3 NSs and large p‐n junction areas of 3D heterojunction structure enable a strong light absorption and effective carrier transport and collection, and thus a power conversion efficiency (PCE) of 1.45% was achieved. Moreover, this PCE is the highest ever reported for BiI3 based solar cells to our best knowledge. Moreover, the nonencapsulated device remained 96% of the initial PCE after 24 h continuous one sun illumination at ~70% humidity condition, and 82% of the initial PCE after 1‐month storage at ~30% humidity condition. [ABSTRACT FROM AUTHOR]