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Abstract We introduce a new paradigm for generating high-purity vortex beams with metasurfaces. By applying optical neural networks to a system of cascaded phase-only metasurfaces, we demonstrate the efficient generation of high-quality Laguerre-Gaussian (LG) vortex modes. Our approach is based on two metasurfaces where one metasurface redistributes the intensity profile of light in accord with Rayleigh-Sommerfeld diffraction rules, and then the second metasurface matches the required phases for the vortex beams. Consequently, we generate high-purity LG p,l optical modes with record-high Laguerre polynomial orders p = 10 and l = 200, and with the purity in p, l and relative conversion efficiency as 96.71%, 85.47%, and 70.48%, respectively. Our engineered cascaded metasurfaces suppress greatly the backward reflection with a ratio exceeding −17 dB. Such higher-order optical vortices with multiple orthogonal states can revolutionize next-generation optical information processing.

Though broadband achromatic metalens are attractive for biological applications, existing metalenses show limited performance in the biological imaging window. Here, the authors report high-efficiency broadband achromatic metalens featuring record-high aspect ratio titanium dioxide metasurfaces.

Abstract Broadband light trapping and field localization is highly desired in enhanced light-matter interaction, especially in harmonic generations. However, due to the limited resonant bandwidth, most periodic plasmonic nanostructures cannot cover both fundamental excitation wavelength and harmonic generation wavelength simultaneously. Therefore, most previously reported plasmonic nonlinear optical processes are low in conversion efficiency. Here, we report a strong enhancement of second harmonic generation based on a three-layered super absorbing metasurface structure consisting of a dielectric spacer layer sandwiched by an array of random metallic nanoantennas and a metal ground plate. Intriguingly, the strong light trapping band (e.g. >80%) was realized throughout the entire visible to near-infrared spectral regime (i.e., from 435 nm to 1100 nm), enabling plasmonically enhanced surface harmonic generation and frequency mixing across a broad range of excitation wavelengths, which cannot be achieved with narrow band periodic plasmonic structures. By introducing hybrid random antenna arrays with small metallic nanoparticles and ultra-thin nonlinear optical films (e.g. TiO2) into the nanogaps, the nonlinear optical process can be further enhanced. This broadband light-trapping metastructure shows its potential as a building block for emerging nonlinear optical meta-atoms.

Stimulated emission depletion nanoscopy and its derivatives based on saturation induced competition effects have become an indispensable tool for studying cellular events and their dynamics in living conditions. The successful implementation of these techniques heavily relies on the competition between excitation induced spontaneous emission and stimulated emission from fluorescent dyes. The use of two laser beams at different wavelengths perplexes the optical system and the high intensity saturation beam inevitably introduces detrimental photobleaching effects. Harnessing the emerging saturation scattering of plasmonic nanoparticles, here, we demonstrate a novel fluorescence-free single-wavelength super-resolution imaging technique using gold nanoparticles. A lateral resolution of 101.2 nm (

ABSTRACT: Cinnamomi Cortex was a material as medicinal and edible resources and it has been demonstrated that Cinnamomi Cortex aqueous extract (CCAE) possess hypoglycemic effect, but there were no active compounds identified as quality standard of CCAE to be used in the investigate of hypoglycemic activity. Hence, in this study, the quality standard and the hypoglycemic effect of CCAE were investigated. Cinnamaldehyde and coumarin as the quality control in CCAE were analyzed by high performance liquid chromatography (HPLC) method. The results showed that the average yield of extraction was 10.06%. The concentration of coumarin was linear with peak area ranging from 0.02–1.00 μg/mL (r = 0.999 6, n = 6) and that of cinnamaldehyde also demonstrated a good linear relationship with peak area in the range of 1.05–52.50 μg/mL (r = 0.999 7, n = 6). The average recovery rate of coumarin and cinnamaldehyde was 99.42% and 100.11%, respectively. The investigation of hypoglycemic effect revealed that CCAE could improve weight loss, lower liver and pancreas indices, improve organ damage caused by diabetes, and lower fasting blood glucose, glycosylated serum protein (GSP) and total cholesterol (TC) levels. The results showed that CCAE can reduce fasting blood glucose and blood lipid levels in diabetic mice.

Central fatigue is a common pathological state characterized by psychological loss of drive, lack of appetite, drowsiness, and decreased psychic alertness. The mechanism underlying central fatigue is still unclear, and there is no widely accepted successful animal model that fully represents human characteristics. We aimed to construct a more clinically relevant and comprehensive animal model of central fatigue. In this study, we utilized the Modified Multiple Platform Method (MMPM) combined with alternate-day fasting (ADF) to create the animal model. The model group rats are placed on a stationary water environment platform for sleep deprivation at a fixed time each day, and they were subjected to ADF treatment. On non-fasting days, the rats were allowed unrestricted access to food. This process was sustained over a period of 21 days. We evaluated the model using behavioral assessments such as open field test, elevated plus maze test, tail suspension test, Morris water maze test, grip strength test, and forced swimming test, as well as serum biochemical laboratory indices. Additionally, we conducted pathological observations of the hippocampus and quadriceps muscle tissues, transmission electron microscope observation of mitochondrial ultrastructure, and assessment of mitochondrial energy metabolism and oxidative stress-related markers. The results revealed that the model rats displayed emotional anomalies resembling symptoms of depression and anxiety, decreased exploratory behavior, decline in learning and memory function, and signs of skeletal muscle fatigue, successfully replicating human features of negative emotions, cognitive decline, and physical fatigue. Pathological damage and mitochondrial ultrastructural alterations were observed in the hippocampus and quadriceps muscle tissues, accompanied by abnormal mitochondrial energy metabolism and oxidative stress in the form of decreased ATP and increased ROS levels. In conclusion, our ADF+MMPM model comprehensively replicated the features of human central fatigue and is a promising platform for preclinical research. Furthermore, the pivotal role of mitochondrial energy metabolism and oxidative stress damage in the occurrence of central fatigue in the hippocampus and skeletal muscle tissues was corroborated.

Proton exchange membrane fuel cells (PEMFCs) are considered a promising energy source in the field of transport and distributed power generation. Fundamental research into their key components is needed to improve PEMFC performance and accelerate commercialization. Binder addition and compression induced by assembly pressure can significantly change the microstructure of the gas diffusion layer and affect mass transport. A two-dimensional multicomponent lattice Boltzmann (LB) model considering the cathode electrochemical reaction was developed, and a GDL was reconstructed numerically and considering a binder structure. The effects of the binder and compression on mass transport and electrochemical performance within the GDL were investigated. The results showed that an increase in binder volume fraction led to more chain-like structures and closed pores that were unfavorable for mass transport. Compression increased the mass transfer resistance of the GDL in the region under the rib, leading to a decrease in oxygen concentration and local current density.

Demands for dietary supplements with anti-fatigue effects are growing fast due to increasing societal demands. Moreover, in highly physically active individuals, there are also significant needs for supplements to improve exercise performance. The present study evaluated the potential anti-fatigue and anti-oxidant effects of curcumin in mice using exhaustive swimming test. Male C57BL/6J mice were randomized into six groups: blank control (Rest), swimming control (Con), Vitamin C (Vc), low-dose curcumin (C50), middle-dose curcumin (C100), and high-dose curcumin (C200). After a 4-week intervention, the mice in all groups except the Rest group were subject to an exhaustive swimming test. Then, mice were sacrificed to examine serum biochemical markers and fatigue-related enzymes. Moreover, the gene and protein expressions of signal transduction factors involved in the Nrf2/Keap1 signaling pathway were measured. The results indicated that curcumin significantly enhanced the exercise tolerance of mice in the exhaustive swimming test. Particularly, the swimming time of mice in the C100 group was increased by 273.5% when compared to that of mice in the Con group. The levels of blood urea nitrogen, blood ammonia, lactic acid, creatine kinase and lactate dehydrogenase in the C100 group were decreased by 13.3%, 21.0%, 18.6%, 16.7% and 21.9%, respectively, when compared to those of mice in the Con group. Curcumin alleviated exercise-induced oxidative stress and significantly enhanced the activities of superoxide dismutase, catalase and glutathione peroxidase by activating the Nrf2 signaling. These findings indicated that curcumin supplementation exerted remarkable anti-oxidant and anti-fatigue effects in mice, providing additional evidence supporting the use of curcumin as functional food, especially by those engaged in sports-related activities.

BackgroundAlthough a plethora of studies have employed multiple gallbladder cancer (GBC) cell lines, it is surprisingly noted that there is still lack of a normal gallbladder epithelial cell line as a normal counterpart, thus impeding substantially the progress of mechanistic studies on the transformation of normal epithelial cells to cancer. Here, we created a normal gallbladder epithelial cell line named L-2F7 from human gallbladder tissue.MethodsGallbladder tissues from a diagnosed cholecystitis female patient were collected, and epithelial cells were enriched by magnetic cell sorting. Then, the cells were immortalized by co-introduction of human telomerase reverse transcriptase (hTERT) and Simian virus 40 large T antigen (LT-SV40) via a lentivirus infection system. After clonal selection and isolation, L-2F7 cells were tested for epithelial markers CK7, CK19, CK20, and CD326, genomic feature, cell proliferation, and migration using Western blot, immunofluorescence, whole genome sequencing, karyotyping, and RNA sequencing. L-2F7 cells were also transplanted to Nude (nu/nu) mice to determine tumorigenicity.ResultsWe successfully identified one single-cell clone named L-2F7 which highly expressed epithelial markers CD326, CK7, CK19, and CK20. This cell line proliferated with a doubling time of 23 h and the epithelial morphology sustained over 30 passages following immortalization. Transient gene transduction of L-2F7 cells led to expression of exogenous GFP and FLAG protein. L-2F7 cells exhibited both distinct non-synonymous mutations from those of gallbladder cancer tissues and differential non-cancerous gene expression patterns similar to normal tissue. Although they displayed unexpected mobility, L-2F7 cells still lacked the ability to develop tumors.ConclusionWe developed a non-cancerous gallbladder epithelial cell line, offering a valuable system for the study of gallbladder cancer and other gallbladder-related disorders.

Water management within the gas diffusion layer (GDL) plays an important role in the performance of the proton exchange membrane fuel cell (PEMFC) and its reliability. The compression of the gas diffusion layer during fabrication and assembly has a significant impact on the mass transport, and the porosity gradient design of the gas diffusion layer is an essential way to improve water management. In this paper, the two-dimensional lattice Boltzmann method (LBM) is applied to investigate the two-phase behavior in gas diffusion layers with different porosity gradients under compression. Compression results in an increase in flow resistance below the ribs, prompting the appearance of the flow path of liquid water below the channel, and liquid water breaks through to the channel more quickly. GDLs with linear, multilayer, and inverted V-shaped porosity distributions with an overall porosity of 0.78 are generated to evaluate the effect of porosity gradients on the liquid water transport. The liquid water saturation values within the linear and multilayer GDLs are significantly reduced compared to that of the GDL with uniform porosity, but the liquid water within the inverted V-shaped GDL accumulates in the middle region and is more likely to cause flooding.

As the two largest developing countries globally, China and India have become the top 1 and 3 carbon emitters, respectively. Quantitating their CO2 emissions in terms of the characteristics and driving factors is highly significant to mitigating global climate change. This study compiled the CO2 emission inventories from 1990 to 2017 in China and India. The Tapio model and index decomposition analysis were used to analyze the impact of socio-economic factors on CO2 emissions. We found that 1) CO2 emissions of China and India reached 9526 and 2242 Mt, respectively, in 2017. CO2 emissions increased during 1990–2017 with an average annual growth rate of 5% in both countries. 2) In China, the economic development has remained weakly decoupling from emissions since 2012, reaching a strong decoupling (-0.2) in 2017. In contrast, the contribution of India’s economy to emissions continued to increase, and the decoupling status showed continuous fluctuations. 3) Economic development and population explosion were the dominant factors driving CO2 emissions in the countries. The effect of energy intensity inhibited India’s emissions growth after 2008 with an impact degree lower than China. Overall, our findings on the impact of the economy and emission development may provide references for other developing countries at different stages to achieve low-carbon development.

In the face of the development of the information technology in the port and waterway,the Internet of things (IoT) technology can help to build China’s water transport perception network.The big data analysis of the waterborne transport has become a hot topic for researchers and practitioners in the field of transportation.The navigation density of each port in the water transportation is nonlinear and spatio-temporal correlation,so it is a great challenge to accurately predict it.A multi-feature spatiotemporal graph convolution network (MFSTGCN) was proposed to solve the problem of the traffic density prediction.MFSTGCN effectively captured the spatial-temporal correlation of the ship navigation density data by using the spatial convolution and temporal convolution through three features,which were navigation volume,average ship speed and ship density.The experiment was carried out on the automatic identification system (AIS) data set collected from a shipping platform.The results show that the prediction effect of the MFSTGCN model is better than the spatio-temporal graph convolution network (STGCN) model.

Aims: Irradiation is an effective treatment for tumors but has been associated with cardiac dysfunction. However, the precise mechanisms remain incompletely elucidated. This study investigated the long-term cardiac damage associated with abdominal irradiation and explored possible mechanisms.Methods and Results: Wild-type C57BL6/J mice were divided into two groups: untreated controls (Con) and treatment group receiving 15 Gy of abdominal gamma irradiation (AIR). Both groups received normal feeding for 12 months. The AIR group showed reductions in left ventricular ejection fraction (LVEF), fractional shortening (FS), left ventricular end-diastolic internal diameter (LVID; d), left ventricular end-diastolic volume (LV Vol. diastolic volume (LV Vol; d) and mitral transtricuspid flow late diastolic filling velocity (MV A). It also showed increased fibrosis, reduced conduction velocity and increased conduction heterogeneity. Non-targeted metabolomics showed the differential metabolites were mainly from amino acid metabolism. Further KEGG pathway annotation and enrichment analysis revealed that abnormalities in arginine and proline metabolism, lysine degradation, d-arginine and d-ornithine metabolism, alanine, aspartate and glutamate metabolism, and arginine biosynthesis.Conclusion: Abdominal irradiation causes long-term damage to the non-irradiated heart, as reflected by electrical and structural remodeling and mechanical dysfunction associated with abnormal amino acid biosynthesis and metabolism.

The performance degradation issue caused by carbon deposition has limited the commercial application of natural-gas-fueled solid oxide fuel cells. Most previous corresponding studies are based on thermodynamic equilibrium analyses, while long-term transient evaluation work is lacking. Therefore, a transient multi-physics numerical model is developed in present work. The corresponding long-term performance degradation evaluation is then conducted. The results show that, for a direct internal reforming solid oxide fuel cell, the increase in carbon deposition and deterioration of performance degradation were concentrated in the first 180 days of steady−state operation and slowed down at the later stage. The electrode inlet rapidly developed a high concentration of carbon deposition after 180 days of steady−state operation. The deposited carbon deteriorated the gas transport and decayed reaction activity within the porous electrode, eventually inducing a deactivation zone with 0 current density at the inlet. Key measures to inhibit carbon deposition should be implemented within the first 180 days of operation, and the pre-reformed operation of natural gas is encouraged for natural-gas-fueled solid oxide fuel cells.

Although promising results have been achieved in the restoration of complex illumination images with the Retinex algorithm, there are still some drawbacks in the processing of Retinex. Considering the noise characteristics of complex illumination images, in this study, we propose a novel restoration algorithm for noisy complex illumination, which combines guided adaptive multi‐scale Retinex (GAMSR) and improvement BayesShrink threshold filtering (IBTF) based on double‐density dual‐tree complex wavelet transform (DDDTCWT) domain. Extensive restoration experiments are conducted on three typical types images and the same image with different noises. On the basis of a series of evaluation indexes, we compare our method to those of state‐of‐the‐art algorithms. The results show that (i) SSIM of the proposed IBTF is superior to traditional Bayes threshold method by 15% as the standard variance is 100. (ii) PSNR of the proposed GAMSR enhances 15% to traditional MSR. (iii) The clarity of final results for restoration speeds up three times than that of original images, and the information entropy is improved slightly too. Therefore, the proposed method can effectively enhance the details, edges and textures of the image under complex illumination and noises.