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By performing DFT computations, we proposed a promising strategy to tune the ORR/OER catalytic performance of transition metal-nitrogen-carbon by constructing heterostructure with graphdiyne. We found the d-band center and charge transfer of the TM active sites can correlate the ORR/OER catalytic activity and their electronic properties for TM N C/GDY. [Display omitted] • The catalytic activities of the heterostructure between TM N C with GDY (TM N C/GDY) for ORR/OER were studied by means of density functional theory. • Co N C/GDY can be proposed as a bifunctional catalyst for ORR/OER with low overpotential. • According to the constant-potential method, the acidic condition is conducive to boost bifunctional catalytic activity for Co N C/GDY. Exploring high-efficiency electrocatalysts to boost the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is pivotal to the large-scale applications for clean and renewable energy technologies, such as fuel cells, water splitting, and metal–air batteries. Herein, by means of density functional theory (DFT) computations, we proposed a strategy to modulate the catalytic activity of transition metal-nitrogen-carbon catalysts through their interface engineering with graphdiyne (TM N C/GDY). Our results revealed that these hybrid structures exhibit good stability and excellent electrical conductivity. Especially, Co N C/GDY was identified as a promising bifunctional catalyst for ORR/OER with rather low overpotentials in acidic conditions according to the constant-potential energy analysis. Moreover, the volcano plots were established to describe the activity trend of the ORR/OER on TM N C/GDY using the adsorption strength of the oxygenated intermediates. Remarkably, the d-band center and charge transfer of the TM active sites can be utilized to correlate the ORR/OER catalytic activity and their electronic properties. Our findings not only suggested an ideal bifunctional oxygen electrocatalyst, but also provided a useful strategy to obtain highly efficient catalysts by interface engineering of two-dimensional heterostructures. [ABSTRACT FROM AUTHOR]

The coining technology produces a wide variety of commemorative coins with exquisite patterns. However, it often encounters defects such as insufficient filling, flash lines, light bands, and so on. Process engineers usually perform multiple tryouts to avoid the above-mentioned problems in actual production. This is not only time-consuming and laborious but also ineffective. The virtual tryout of the finite element method (FEM) could assist engineers to avoid the defects in the coining process with a great improvement in product quality. In order to exactly describe complex patterns of commemorative coins, a large number of elements are employed in the classical FEM. Even then, the three dimensional elements, which come in early contact with the reliefs of the punch/die, undergo large deformation and become distorted. Errors of contact judgment between the tools and the workpiece in the FEM occur during the simulation process. Taking into account the advantage of Non-Uniform Rational B-Spline (NURBS) basis functions when accurately describing complex boundaries or surfaces, isogeometric analysis (IGA) is developed for studying the material filling of coin cavities. Six numerical examples involving elastic and plastic analyses with/without contact issues are considered by the presented IGA frameworks and show good performance of the present method in simulating the cavity filling compared with ABAQUS. In addition, numerical findings also indicate that the proposed method exhibits excellent contact detection and strong anti-mesh distortion in large deformation of the coining process. These encouraging observations motivate us to explore the NURBS description of complicated reliefs of coins and the corresponding IGA framework for the coining process. [ABSTRACT FROM AUTHOR]

Clinical trials using fetal retinal pigment epithelium (fRPE), human embryonic stem cell (hESC)-derived RPE, or human induced pluripotent stem cell (hiPSC)-derived RPE for cell-based therapy for degenerative retinal diseases have been carried out. We investigated the culture-induced changes in passaged fRPE, hESC-RPE, and hiPSC-RPE cells and explored the differentiation and maturation effect of all-trans retinoic acid (ATRA) on cells for manufacturing and screening high-quality RPE cells for clinical transplantation. RPE cell lines were set up and the culture-induced changes in subsequent passages caused by manipulating plating density, dissociation method, and repeated passaging were studied by a microscope, real-time quantitative PCR, western blot, and immunofluorescent assays. Gene and protein expression and functional characteristics of RPE cells incubated with ATRA were evaluated. Compared with fRPE, hESC-RPE, and hiPSC-RPE showed decreased gene and protein expression of RPE markers. RPE cells underwent mesenchymal changes showing increased expression of mesenchymal markers including a-SMA, N-cadherin, fibronectin and decreased expression of RPE markers including RPE65, E-cadherin, and ZO-1, as a subsequence of low plating density, inappropriate dissociated method, and repeated passaging. RPE cells treated by ATRA showed increased expression of RPE markers and increased expression of negative complement regulatory proteins (CRPs) and increased transepithelial resistance as well. Differences in protein and gene expression among three RPE types exist. ATRA can increase RPE markers, CRPs gene expression in fRPE, and stem cell-derived RPE. These can be used to guide the standard of screening RPE cells for clinical translational cell therapy. [ABSTRACT FROM AUTHOR]

To explore the main aroma components and aroma differences of black tea produced from two tea cultivars, Fuyun 6 and Jinguanyin, E-nose and GC–MS were adopted. The results showed that black tea made of Jinguanyin had a floral aroma, while black tea of Fuyun 6 had a sweet aroma in the sensory review. Forty-six aroma substances in the 2 cultivars were found by GC–MS; 9 aroma substances had significant differences, including heptaldehyde, furfural, 2,2,6-trimethylcyclohexanone, 2-pentadec-2-enylfuran, cis-3-hexenyl acetate, carveol, methyl salicylate, 5-methyl-2-hexanone, and hexanal. Furthermore, the results of the E-nose showed that five out of the ten sensors were able to discriminate the two cultivars, especially, S2 (sulphide and hydrogen sulphide), S6 (biogas, hydrocarbons, and methane), S7 (combustible gases) and S10 (combustible gases and alkanes) were necessary sensors for identifying the differences between the two cultivars. The results of this study clarified the characteristics of the aroma compositions and the distinctions between black teas made of Jinguanyin and Fuyun 6. Furthermore, they provided a theoretical basis for the classification of the different cultivars and types of black tea. [ABSTRACT FROM AUTHOR]

A new compact static wind imaging interferometer, called the Birefringent Doppler Wind Imaging Interferometer (BIDWIN), has been developed for the purpose of observing upper atmospheric winds using suitably isolated airglow emissions. The instrument combines a field-widened birefringent delay plate placed between two crossed Wollaston prisms with an imaging system, waveplates and polarizers to produce four fixed 90 ∘ phase-stepped images of the interference fringes conjugate to the scene of interest. A four-point algorithm is used to extract line-of-sight Doppler wind measurements across the image of the scene. The arrangement provides a similar throughput to that of a field-widened Michelson interferometer; however, the interferometric component of BIDWIN is smaller, simpler to assemble and less complicated to operate. Consequently, the instrument provides a compact, lightweight and robust alternative that can be constructed and operated with lower cost. In this paper, the instrument concept is presented, and the design and optimization of a prototype version of the instrument are discussed. Characterization of the lab prototype is presented, and the performance of the instrument is examined by applying the instrument to measure a low-velocity two-dimensional Doppler wind field with a high precision (5 m s -1) in the lab. [ABSTRACT FROM AUTHOR]

[Display omitted] • M-N-C/MoS 2 heterostructures exhibit good structural stability, excellent electrical conductivity, and improved stiffness. • The anchored Ir-N-C, Rh-N-C, and Co-N-C are identified as eligible bifunctional ORR/OER electrocatalysts. • The optimal binding strength with the oxygenated intermediates endow anchored M-N-C good catalytic performance. The development of highly-efficient bifunctional oxygen electrocatalysts is essential to the large-scale commercialization of energy-related conversion and storage technologies. In this work, using first-principle computations, we systematically investigated the catalytic activities of a variety of metal-N-C/MoS 2 heterostructures (M-N-C/MoS 2 , M = Cr, Mn, Fe, Co, Ni, Cu, Zn, Ru, Rh, Pd, Ag, Os, Ir, and Pt) towards the oxygen reduction/evolution reactions (ORR/OER). Our result revealed that these M-N-C/MoS 2 heterostructures exhibit good structural stability, excellent electrical conductivity, and improved stiffness. Furthermore, the anchored Ir-N-C was identified as the best bifunctional ORR/OER electrocatalyst due to its lowest overpotentials (0.28/0.38 V) among all candidates, which were well rationalized by its optimal binding strength with the oxygenated intermediates. Thus, by combining M-N-C and MoS 2 monolayer, the highly-efficient bifunctional ORR/OER electrocatalysts can be achieved, which offers a new strategy to further explore heterostructures-based materials for other electrochemical processes. [ABSTRACT FROM AUTHOR]

Image segmentation is an essential step in medical image analysis, as its results directly affect the quality of the follow-up analysis. Because of the high calculation speed and the good performance of the segmentation algorithms based on neural networks (NNs), image segmentation has been extensively researched and developed in clinical analysis and applications. However, the existing NN-based image segmentation methods only consider the pixel information of the image that needs to be segmented, and they cannot guarantee the continuity and smoothness of the segmented edge. Consequently, we propose the model and data-driven hybrid approach, namely, the model-data-driven hybrid-fusion network for medical image segmentation. We consider the attention mechanism and the high-low features, and embed the traditional curvature regularisation segmentation model into the NN in the form of a loss function. Moreover, our model considers not only the semantic information of the segmented image but also the boundary length information of the ROI and the target region information. These can ensure the smoothness of the edge of the medical image segmentation results. We conduct intensive experiments on several benchmark datasets to evaluate the effectiveness of our method in dealing with complex backgrounds and noise. Experimental results demonstrate that the proposed model outperforms other state-of-the-art segmentation methods. • We propose a loss function that combines contour length and region information and adds an elastic energy term to it, which tackles the problem of the unsmooth borders caused by purely network training. • We introduce a curvature based regularization function into the segmentation model to regularize the contour length term and improve the over-fitting phenomenon in network training. • We use a new network of a dual-path feature extraction module (DP-FEM) with channel attention and a high-level and low-level feature fusion module (HLFFM) with spatial attention, which improves the accuracy of training. • The results of the proposed fusion network segmentation are analysed with multiple existing models. The results prove that our proposed model can obtain reasonable image segmentation results on datasets, such as remote projection and fundus colour images. [ABSTRACT FROM AUTHOR]

Channeled spectropolarimetry is a snapshot scheme for the full polarization spectra measurement. It has the advantages of static, compact, lightweight, and easy to implement. However, while the broadband polarization spectra can be precisely reconstructed using the regular methods, such as the method based on the Fourier transform, the reconstruction of narrowband polarization spectra always suffers from errors caused by the crosstalk among channels in the optical path difference domain. We present an efficient narrowband full polarization spectra reconstruction method for channeled spectropolarimetry. The line shape of the intensity spectrum is estimated by the envelop curve of the measured high frequency modulated spectrum. The full polarization spectra can be reconstructed by the least-square method under the assumption that polarization states change slowly with wavelength for narrowband polarization spectra. The feasibility of the reconstruction method has been verified by the simulation and experimental results. [ABSTRACT FROM AUTHOR]

Appendiceal cancers are usually diagnosed after appendectomy accidentally. The need for subsequent right hemicolectomy in these patients was determined by the potential risk of regional lymph node (LN) metastasis. Establishing a nomogram to forecast the potential risk of lymph node metastasis of appendiceal cancer could help in the next step of treatment. Patients with appendiceal cancer undergoing surgery was queried in the American cancer database of Surveillance, Epidemiology and End Results database from 2004 to 2016. A nomogram was established based on Logistic regression model. Finally, 3,075 patients were diagnosed with appendectomy cancer from 2004 to 2016. Among them, there were 2028 (65.9%) cases with negative lymph nodes, 1047 (34.1%) cases with positive lymph nodes. Risk factors associated with lymph node metastasis include age, histological type, tissue grade, T stage, distant metastasis, and tumor size. We drew the ROC curves of the training group（0.754, P < 0.001） and the validation group （0.775, P < 0.001） respectively. C-index values of predictions were 0.772 (95%CI, 0.750-0.793) and 0.776 (95%CI, 0.746-0.807), and Brier score were 0.178 and 0.172 in training and validation group respectively. All of them showed excellent performance of the nomogram in our study. A new nomogram was created to assess the potential risk of LN metastasis in patients of appendiceal cancer by utilizing age, tumor histology, tumor pathologic grade, tumor size, T-stage, and M-stage. The nomogram could provide a strong reference for the right hemicolectomy and facilitate clinic decision. [ABSTRACT FROM AUTHOR]

[Display omitted] • Calcined Ge-UTL encountered structural degradation under pure water solution at RT. • A simply ultrasonic treatment caused random arrangement of the formed cfi layers. • The stacking faults of cfi layers generated abundant intracrystal mesopores. • An excellent styrene epoxidation activity (TOF = 403 h−1) is achieved on Co-Meso-UTL. Co-zeolites with hierarchical porous are significantly desirable for the liquid-phase selective epoxidation of styrene that required relatively open reaction spaces. A typical UTL germanosilicate with the absence of organic structure-directing agent molecules inside pore channels suffered from severe structural collapse after ultrasonic treatment under pure water medium, originating from the unstable germanium-rich double four ring subunits. The simple strategy cleaved the weak linkage Ge-O bands and caused the irregular location of silicon-rich cfi layers. Subsequently, Co activity centers was incorporated into the framework through reacting with the abundant silanol groups located in the hydroxyl nests at room temperature. The random arrangement of mono- or multi- cfi layers induced the stacking faults and generated a large amount of intracrystal mesopores after calcination. The resultant Co-Meso-UTL catalysts favored the molecules diffusion of large-sized styrene and target products, improving the accessibility of Co active sites and exhibiting excellent catalytic performance in the styrene epoxidation reaction with single hydrogen peroxide (H 2 O 2) oxidant. Especially, high styrene oxide product selectivity was also obtained through controlling appropriate H 2 O 2 -added content as well as reaction time, which possessed a highest turnover frequency value of 403 h−1 among the reported catalysts. [ABSTRACT FROM AUTHOR]

The Mars Atmospheric Wind Imaging Interferometer offers several advantages, notably its high throughput, enabling the acquisition of precise and high vertical resolution data on the temperature and wind fields in the Martian atmosphere. Considering the current absence of such an Interferometer, this paper introduces a novel Mars wind field imaging interferometer. In analyzing the photochemical model of O2 (a1Δg) 1.27 μm molecular airglow radiation in the Martian atmosphere and considering the impact of instrument signal-to-noise ratio (SNR), we have chosen an optical path difference (OPD) of 8.6 cm for the interferometer. The all-solid-state polarized wind imaging interferometer is miniaturized by incorporating two arm glasses as the compensation medium in its construction, achieving the effects of field-widening and temperature compensation. Additionally, an F-P Etalon is designed to selectively filter the desired three spectral lines of O2 dayglow, and its effect is evaluated through simulations. The accuracy of the proposed compact Mars polarized wind imaging interferometer for detecting Mars' wind field and temperature field has been validated through rigorous theoretical derivation and comprehensive computer simulations. The interferometer boasts several advantages, including its compact and small size, static stability, minimal stray light, and absence of moving parts. It establishes the theoretical, technological, and instrumental engineering foundations for future simultaneous static measurement of Martian global atmospheric wind fields, temperature fields, and ozone concentrations from spacecraft, thereby significantly contributing to the dataset for investigating Martian atmospheric dynamics. [ABSTRACT FROM AUTHOR]

[Display omitted] • Calcined *CTH experienced structural collapse and reconstruction by HNO3 treatment. • Sn-*CTH were post-synthesized via the structural rearrangement and Sn incorporation. • Sn-*CTH exhibited a high catalytic activity in the Baeyer-Villiger oxidation. • High ε-caprolactone selectivity was obtained through controlling reaction parameters. Germanium-rich *CTH zeolite without organic molecules located inside pore channels experienced only partial structural collapse and subsequently repaired to high-silica structure analogous to the original topology in a short time. The surprise acid-hydrolysis process has caused a large amount of framework Ge ions were removed, giving rise to abundant hydroxyl nests. Benefiting from the unexpected variation of framework structure and chemical composition, stannosilicates Sn-*CTH with extra-large pores and various Sn loadings (Si/Sn molar ratio in the range of 30-∞) were post-prepared depending on the reaction between the added (NH 4) 2 SnCl 6 species and the formed silanol groups in the hydroxyl nests. The resultant Sn-*CTH zeolites were able to release significantly the diffusion limitations encountered by the bulky substrates and oxidants, exhibiting promising activities to catalyze the Baeyer-Villiger (B-V) oxidation of ketones with single oxidant either hydrogen peroxide (H 2 O 2) or large-sized tert-butyl hydroperoxide (TBHP). Especially, high ε-caprolactone product selectivity was also obtained in the B-V oxidation of cyclohexanone using H 2 O 2 oxidant through reducing the H 2 O 2 /cyclohexanone molar ratio as well as controlling appropriate reaction time, which was more efficient than the traditional Sn-Beta-F catalyst. [ABSTRACT FROM AUTHOR]

Here, L1 (2‐(pyridin‐2‐yl)quinoxaline) and L2 ((1‐((1H‐pyrrol‐2‐yl)ethylidene)benzene‐1,2‐diamine) ⋅ (1‐(1H‐pyrrol‐2‐yl)ethanone)) were synthesized and reacted with CoCl2 ⋅ 6H2O and NiCl2 ⋅ 6H2O to produce complexes 1–4. We found several interesting pieces of crystal structure information. Firstly, ligands L1 and L2 with completely different molecular structures were obtained by reacting the precursors containing similar N‐heterocycles with 1,2‐diaminobenzene. Secondly, in methanol and DMF solvents, 1 showed two structures, the binuclear and mononuclear cobalt complexes 1 a and 1 b. Finally, the structure of 4 showed the formation of a new 2 : 1 type ligand at eutectic L2 in the presence of a Ni2+ template. Upon treatment with AIBN, 1–4 showed moderate to high activities for MMA polymerization, producing PMMA with low to high molecular weights (2.02∼73.03×104 g⋅mol‐1) and moderate dispersity indices (PDI: 1.72∼3.32). Moreover, 1 b displayed higher catalytic activities (up to 1.138×105 g mol−1 ⋅ h−1), which was 20 times higher than that of 3 and more than 7 times higher than that of 1 a. [ABSTRACT FROM AUTHOR]

The basic principle of the near-infrared static wind imaging interferometer (NIR-SWINDII) is expounded. The instrument can simultaneously detect the atmospheric wind speed, temperature, and ozone concentration in the middle and lower thermosphere (25–110 km). According to the optical transmission principle, the exact expression of the ideal and actual optical throughput of the NIR-SWINDII is obtained. To analyze and discuss the influence of the field of view, wavelength, and refractive index systematically, we select a high refractive index and a low refractive index glass matching schemes according to the "full compensation" principle of the wide-field Michelson interferometer, the simulation of NIR-SWINDII's optical throughput is carried out. For the high refractive index matching scheme, the results show that when the field of view is within 3 degrees, the transmittance of the NIR-SWINDII can reach 23.38%, and the optical throughput of the entire system is about 0.1024 cm2 ⋅ sr. Comparing with the parameters of other instruments, it is found that our instrument's optical throughput performance is comparable to other instruments. This research provides the theoretical basis and practical guidance for the throughput optimization of the NIR-SWINDII. [ABSTRACT FROM AUTHOR]

This article investigated the interaction mechanism between carbon monoxide (CO) and lignite organic matter in lignite liquefaction systems. The study found that a CO atmosphere can facilitate lignite conversion, but its hydrogen supply capacity is poor, resulting in lower liquefaction effects compared to an H 2 atmosphere. Increasing the initial reaction pressure and CO content can enhance the conversion of lignite to low molecular compounds. In-situ studies on lignite pyrolysis in CO and N 2 atmospheres show that CO plays an effective role in promoting the fracture of multiple hydrogen bonds present in lignite, which is linked to the water-gas shift reaction that CO takes part. Additionally, CO can also facilitate the breaking of oxygen-containing ether bonds in lignite, thereby eliminating oxygen and producing CO 2 in the gaseous phase. Density functional theory (DFT) calculations demonstrate that CO reacts with the group after the ether bond breaks, which reduces the formation energy of the product and promotes the ether bond breaking. In summary, CO in syngas may benefit the breaking of ether and hydrogen bonds in lignite during liquefaction, thus promoting lignite conversion. [Display omitted] • The interaction mechanism between CO and lignite organic matter in liquefaction was studied. • CO in syngas may be beneficial to the breaking of ether bond and hydrogen bond in lignite. • CO can promote the conversion of lignite to low molecular compounds during liquefaction. [ABSTRACT FROM AUTHOR]

In a static wind imaging Michelson interferometer (SWIMI) developed by us, two-arm glasses are used to achieve the achromatic thermally compensation. The arm glass is cemented with the beam splitter. The tilt of the arm glass would cause a change to the optical path difference (OPD), thereby reducing the visibility of the interferogram and introducing phase error to the SWIMI system, which eventually responsible for errors in the inversion of temperature and wind velocity. In this paper, we present the principle of static wind imaging interferometer and derivate the variation of OPD caused by the two-dimensional tilt of arm glass in detail. By considering a rectangle incident beam, we analyze the effect of arm glass tilt on wind speed and temperature inversion. The results show that in order to realize the wind velocity error less than 3 m/s, the temperature error less than 3 K, and the instrument visibility greater than 0.8, the two-dimensional tilted angle of arm glass should be less than 1". The tolerance of tilted angle can expand by adjusting the refractive index of the medium on both two sides of the arm glass or by adjusting the reflector mirror of the interferometer precisely. The results would be helpful for the cement of arm glass, beam splitter of SWIMI, and provide a reference for the design of a field-widened wind imaging interferometer. [ABSTRACT FROM AUTHOR]