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Preintercalated Y3+ in layered MnO2 can elaborately regulate the electronic structure, boost electrochemical activity, and render better electrochemical reversibility of MnO2, leading to enhanced energy storage in aqueous Zn-ion batteries.

At 800 °C, the polarization resistances for La0.6Sr0.4Fe0.9Ta0.1O3−δ (LSFT) barely reach 0.02 Ω cm2 in air and 0.1 Ω cm2 in H2, suggesting that LSFT should be a promising electrode for symmetrical proton conducting solid oxide fuel cells.

An asymmetric catalytic approach for the construction of C3-multifunctionalization α-hydroxy-β-amino pyridines has been reported. The products can be accessed by the modulation of two chiral catalysts independently in high yield and with good enantioselectivity. The method features mild reaction conditions and an excellent functional group tolerance. Biological activity analysis shows that the resulting products have a selective antiosteosarcoma activity on 143B cells.

BACKGROUND: The fruit of Vaccinium uliginosum is a natural berry resource that is rich in polyphenols, flavonol glycosides, anthocyanins, and other active substances, indicating its high developmental potential. However, research on V. uliginosum is limited, with no literature available to clarify the germplasm resources suitable for breeding. OBJECTIVE: This study aimed to evaluate the contents of total flavonoids (TF), total anthocyanins (TA), and total phenols (TP) in 10 different populations of V. uliginosum from the Changbai Mountains, China, and investigate the correlation between these functional components and spatial distribution. METHODS: The components and contents of TA, TF, and TP were determined using mass spectrometry, high-performance liquid chromatography, and the Folin–Ciocalteu method, respectively. RESULTS: A total of 15 anthocyanins were detected, and the content of Mal-glu, Pet-glu, and Del-glu was the highest among these anthocyanins. The TF and TA and TP contents were highest in the DFHI and LJII populations, respectively, which can be reasonably developed as excellent populations. The TF content of sample DFHI-8, TA content of LJIII-1 and TP content of LJIII-4 were higher than other samples, which can be used as important breeding germplasm. The content of TF is positively correlated with altitude, while the content of TA and TP is bidirectional, which is positively correlated at 740–838 m and negatively correlated at >838 m. CONCLUSIONS: Significant differences in the contents of TF, TA, and TP in V. uliginosum fruit were found among and within populations, and there was a certain correlation between these contents and their spatial distribution.

Double-layered channels of sinusoid lumen and Disse space separated by fenestrated liver sinusoidal endothelial cells (LSECs) endow the unique mechanical environment of the liver sinusoid network, which further guarantees its biological function. It is also known that this mechanical environment changes dramatically under liver fibrosis and cirrhosis, including the reduced plasma penetration and metabolite exchange between the two flow channels and the reduced Disse space deformability. The squeezing of leukocytes through narrow sinusoid lumen also affects the mechanical environment of liver sinusoid. To date, the detailed flow-field profile of liver sinusoid is still far from clear due to experimental limitations. It also remains elusive whether and how the varied physical properties of the pathological liver sinusoid regulate the fluid flow characteristics. Here a numerical model based on the immersed boundary method was established, and the effects of Disse space and leukocyte elasticities, endothelium permeability, and sinusoidal stenosis degree on fluid flow as well as leukocyte trafficking were specified upon a mimic liver sinusoid structure. Results showed that endothelium permeability dominantly controlled the plasma penetration velocity across the endothelium, whereas leukocyte squeezing promoted local penetration and significantly regulated wall shear stress on hepatocytes, which was strongly related to the Disse space and leukocyte deformability. Permeability and elasticity cooperatively regulated the process of leukocytes trafficking through the liver sinusoid, especially for stiffer leukocytes. This study will offer new insights into deeper understanding of the elaborate mechanical features of liver sinusoid and corresponding biological function.

Heavy metal and harmful element contamination are frequently reported in Chinese herbal medicines (CHMs), and roots and rhizomes parts showed a higher content than other parts. To investigate the residue level and assess the potential human health risk of heavy metals and harmful elements in roots and rhizomes, 720 batches of the sample representing 20 species of herbs from different sources were collected.The content of Pb, Cd, As, Hg, and Cu in the digests was determined using ICP-MSCompared with the Chinese limit standard (Chinese Pharmacopoeia Commission, 2020 edition) of Pb, Cd, As, Hg, and Cu inConsuming raw materials of

The development of detection methods for oriented object detection remains a challenging task. A considerable obstacle is the wide variation in the shape (e.g., aspect ratio) of objects. Sample selection in general object detection has been widely studied as it plays a crucial role in the performance of the detection method and has achieved great progress. However, existing sample selection strategies still overlook some issues: (1) most of them ignore the object shape information; (2) they do not make a potential distinction between selected positive samples; and (3) some of them can only be applied to either anchor-free or anchor-based methods and cannot be used for both of them simultaneously. In this paper, we propose novel flexible shape-adaptive selection (SA-S) and shape-adaptive measurement (SA-M) strategies for oriented object detection, which comprise an SA-S strategy for sample selection and SA-M strategy for the quality estimation of positive samples. Specifically, the SA-S strategy dynamically selects samples according to the shape information and characteristics distribution of objects. The SA-M strategy measures the localization potential and adds quality information on the selected positive samples. The experimental results on both anchor-free and anchor-based baselines and four publicly available oriented datasets (DOTA, HRSC2016, UCAS-AOD, and ICDAR2015) demonstrate the effectiveness of the proposed method.

This study investigates the potential use of polyvinyl acetate emulsion in soil strengthening with emphasis on curing condition. Molded clay specimens treated with three polymer contents of 1%, 2%, and 3% (by the weight of dry soil) are cured in dry and humid environment, respectively. Unconfined compression tests are performed on the specimens after 1, 3, and 9 days of curing, and the results are compared with that for the untreated clay specimens. This comparison shows that polyvinyl acetate polymer can enhance soil mechanical properties. It was found that the compressive strength of soil-polymer composite increases significantly with the increase of polymer content and curing time in air-drying condition, which is 24% higher than that of plain soil after 9-day curing. The role of polymer treatment is to provide soil interparticle binding, which becomes particularly important in humid environments. In curing environments of high moisture, polymer-treated soils always have greater strength, but the effectiveness of polymer treatment decreases with polymer content. The scanning electron microscopies indicate that soil structure is reinforced mostly by three-dimensional interparticle polymeric bridges. The tension in polymeric threads and textiles provides the interparticle bonding that prevents the development of cracks.

Molecular aggregation affects the electronic interactions between molecules and has emerged as a powerful tool in material science. Molecular aggregation finds wide applications in the research of new physical effects; however, its value for chemical reaction development has been far less explored. Herein, we report the development of aggregation-enabled alkene insertion into carbon–halogen bonds. The spontaneous cleavage of C–X (X = Cl, Br, or I) bonds generates an intimate ion pair, which can be quickly captured by alkenes in the aggregated state. Additional catalysts or promoters are not necessary under such circumstances, and solvent quenching experiments indicate that the aggregated state is critical for initiating such sequences. The ionic insertion mode and the intimate ion pair mechanism are supported by mechanistic studies, density functional theory calculations, and symmetry-adapted perturbation theory analysis. Results show that the non-aggregated state may quench the transition state and terminate the insertion process.

The structure and mechanical properties of the stomatopod dactyl club have been extensively studied for its extreme impact tolerance, but a systematic, in situ, investigation on the multiscale mechanical responses under high-speed impact has not been reported. Here we reveal the full dynamic deformation and crack evolution process within projectile impacted dactyl using combined fast 2D x-ray imaging and high resolution ex-situ tomography We show hydration states can result in significantly different toughening mechanisms inside dactyl under dynamic loading. We find a previously unreported 3D interlocking structural design in the impact surface and impact region using nano x-ray tomography (nano-CT). Experimental results and dynamic finite element modeling (DFEM) suggest this unique structure plays an important role in resisting catastrophic structure damage and hindering crack propagation. Our work will help to understand the key toughening strategies of biological materials and provide valuable information for biomimetic manufacturing of impact resistant materials in general.

There is a limited amount of data in China on the disease burden of respiratory syncytial virus- (RSV) associated acute lower respiratory infection (ALRI) among young children. This study aimed to estimate the hospitalization rate of RSV-associated ALRI (RSV-ALRI) among children aged 0-59 months in Suzhou, China.All cases from children hospitalized with ALRI who were aged 0-59 months in Suzhou University Affiliated Children's Hospital during January 2010 to December 2014 were retrospectively identified. Detailed diagnosis and treatment data were collected by reviewing each individual's medical chart. In accordance with the World Health Organization (WHO) influenza disease burden estimation, the hospitalization rate of RSV-ALRI among children aged 0-59 months in Suzhou, China, was then estimated.Out of the 28,209 ALRI cases, 19,317 (68.5%) were tested for RSV, of which the RSV positive proportion was 21.3% (4107/19,317). The average hospitalization rate of RSV-ALRI for children aged 0-59 months was 14 (95% confidence interval [CI]:14-14)/1000 children years, and that for children aged 0-5, 6-11, 12-23, and 24-59 months were 70 (95% CI: 67-73), 31 (95% CI: 29-33), 11 (95% CI: 10-12), and 3 (95% CI: 3-3)/1000 children years, respectively.A considerable degree of RSV-ALRI hospitalization exists among children aged 0-59 months, particularly in those under 1 year of age. Therefore, an effective monoclonal antibody or vaccine is urgently needed to address the substantial hospitalization burden of RSV infection.

Multi-class object detection in remote sensing images plays an important role in many applications but remains a challenging task because of scale imbalance and arbitrary orientations of the objects with extreme aspect ratios. In this paper, the Asymmetric Feature Pyramid Network (AFPN), Dynamic Feature Alignment (DFA) module, and Area-IoU regression loss are proposed on the basis of a one-stage cascaded detection method for the detection of multi-class objects with arbitrary orientations in remote sensing images. The designed asymmetric convolutional block is embedded into the AFPN for handling objects with extreme aspect ratios and improving the space representation with ignorable increases in calculation. The DFA module is proposed to dynamically align mismatched features, which are caused by the deviation between predefined anchors and arbitrarily oriented predicted boxes. The refined Area-IoU regression loss, which reconciles two new regression loss functions, the area-guided regression loss and IoU-guided regression loss, is proposed to simultaneously solve the scale imbalance problem and angle sensitivity problem. Experiments on three publicly available datasets, DOTA, HRSC2016, and ICDAR2015, show the effectiveness of the proposed method.

In the field of computer vision, fine-grained visual categorization has attracted a lot of attention and made great progress due to convolutional neural networks and a large number of publicly available datasets. With next-generation sensing technology, RGB-D cameras can provide high-quality synchronized RGB and depth images for solving many computer vision problems. Although RGB-D cameras have been used in the context of multi-view object category detection and scene understanding, they have not been widely used in fine-grained classification. In this paper, we introduce a multiview RGB-D dataset RGBD-FG for fine-grained categorization. Currently, the dataset contains 93,051 RGB-D images covering 19 super-categories and 50 sub-categories of common vegetables and fruit, and is organized in a hierarchical manner. We provide extensive experimental results to establish state-of-the-art benchmarks for our dataset, illustrating its diversity and scope for improvement through future work. We also propose a novel modality-specific multimodal network called FS-Multimodal network, which can solve two limitations of multimodal networks trained based on fine-tuning techniques: over-fitting and lack of effective depth-specific features. We hope that our study lays the foundations for fine-grained categorization of RGB-D data.