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Two new copper-based coordination polymers (CPs), {[CuI(H2PO4)(dpe)]5(dpe)0.5(H2O)7}n (Cu-dpe(I)) and {[CuII(HPO4)(dpe)(H2O)](H2O)3}n (Cu-dpe(II)) (dpe = 1,2-di(4-pyridyl)ethylene), had been successfully constructed by hydrothermal method and ball milling method respectively. The crystal structures of two coordination polymers were determined by single crystal X-ray diffraction. The synthetic temperature caused their structure differences. The differences of structure and properties between these two coordination polymers were discussed. In this work, they both exhibit excellent photocatalytic activity toward the degradation of methylene blue (MB) under visible light. Among them, Cu-dpe(I) and Cu-dpe(II) could degrade MB more than 88.1% in 120 minutes under visible light. Some active free radicals such as ·OH, ·O2-, e- played an important role in degradation of MB. In addition, luminescent experiment revealed Cu-dpe(I) exhibits a relatively high sensitive and selective detection of Fe3+ ions in water solution. Experimental results show that the fluorescence quenching was caused by competitive absorption of excitation wavelength energy between Fe3+ and Cu-dpe(I).

In the urban region of Shenzhen, the changes in the concentration of Black carbon (BC) have been evaluated throughout the dry season, and apportioned the BC sources, including in the form of fossil fuel (e.g., vehicle emissions) and biomass fuel (e.g., industrial emissions).The new seven-channel aethalometer model (AE-33), PMWe revealed that the mean BC concentration was 2672 ± 1506 ng/mThis study showed that the concentration of BC is lower than other regions, and the source allocation is mainly local fossil fuels (vehicle emission, etc.).The online version contains supplementary material available at 10.1007/s40201-022-00793-3.

Calculating the intraocular lens (IOL) power in short eyes for cataract surgery has been a challenge. A meta-analysis was conducted to identify, among several classic and new IOL power calculation formulae, which obtains the best accuracy.All studies aiming at comparing the accuracy of IOL power calculation formulae in short eyes were searched up in the databases of PubMed, EMBASE, Web of Science and the Cochrane library from Jan. 2011 to Mar. 2021. Primary outcomes were the percentages of eyes with a refractive prediction error in ± 0.25D, ± 0.5D and ± 1.0D.Totally 1,476 eyes from 14 studies were enrolled in comparison of 13 formulae (Barrett Universal II, Castrop, Haigis, Hoffer Q, Holladay1, Holladay2, Kane, Ladas Super Formula, Okulix, Olsen, Pearl-DGS, SRK/T and T2). Pearl-DGS had the highest percentage within ± 0.25D. In the ± 0.5D range, Pearl-DGS obtained the highest percentage again, and it was significantly higher than Barrett Universal II, Haigis, Hoffer Q, Holladay1, Holladay2 and Olsen (P = 0.001, P = 0.02, P = 0.0003, P = 0.01, P = 0.007, P = 0.05, respectively). In the ± 1.0D range, Okulix possessed the highest percentage, and it was significantly higher than Barrett Universal II, Castrop, Hoffer Q and Holladay2 (P = 0.0005, P = 0.03, P = 0.003, P = 0.02, respectively).The new generation formulae, based on artificial intelligence or ray-tracing principle, are more accurate than the convergence formulae. Pearl-DGS and Okulix are the two most accurate formulae in short eyes.

Evidence of a connection between living near major roadway and adverse health outcome has come to light. However, little is known about the effect of residential traffic exposure on aging-related physical disability and whether this effect can be modified. We used data derived from Chinese Longitudinal Healthy Longevity Surveys in 2018, with a total of 15,771 participants aged ≥ 65. Residential proximity to major roadway was used as a surrogate for traffic-related air pollution and physical function was measured using basic and instrumental activities of daily living. Logistic regression models were adopted for the analyses. Compared with those living300 m from major road, participants living within 200 m had higher risk of poorer physical functioning. The peak odds ratio was observed in severe disability caused by 101-200 m distance (OR = 1.34, 95% CI: 1.08, 1.66). And this association got stronger with longer duration of living close to major road. In dichotomized analyses using 200 m as a cutoff point, the effect associated with living close to major road was greater in male and current smoker. Specially, poor physical function appears earlier in female, but less severe than that in male. The result emphasizes the adverse effect of residential proximity to major roadways to aging-related declines in health-especially for basic living ability. This association was more pronounced in male and current smokers, which cannot be reversed by lowering the indoor air pollution.

The oxygen reduction reaction (ORR) is the fundamental reaction at the cathode of a fuel cell. Although the commercial precious metal catalyst Pt/C has unique catalytic activity, its high cost, low storage capacity and poor stability limit the commercial application of fuel cells. Therefore, it is essential to explore catalysts with abundant functional materials and develop fuel cells with high activity and high stability. Metal–organic frameworks (MOFs) or porous coordination polymers (PCPs) are highly designable structures composed of organic ligands and metal ions. Because of their large specific surface area, high porosity and tunable chemical structure, MOFs/PCPs are considered the most promising catalytic material for the ORR. This review discusses the research progress and latest development of MOF/PCP applications as ORR catalysts, including the basic principles and the design rules of MOFs/PCPs as ORR catalysts. In addition, this work also elaborates on the active sites of ORR catalysts, which originate from the MOFs/PCPs. Ultimately, we present a research review of the last 5 years and the prospects in the field of using MOFs/PCPs for the fabrication of ORR catalysts.

Exploring the morphology-property relationship is an important role in addressing the mechanism of hydrogen production. In this work, WO3 photocatalysts with different morphology were prepared via a solvothermal method. Our first prepared porous WO3 with the exposed (100) crystal plane, the WO3 porous nano disk demonstrates a better photocatalytic activity, which is higher than the WO3 nanorod, WO3 nanoflower and WO3 nano block. Further characterizations indicate the WO3 porous nano disk exhibits high absorption capacity and active lattice structure. Meanwhile, with the introduction of non-noble metal Ni as the co-catalyst, the photocatalytic H2 evolution was enhanced. This work reveals the importance of regulating surface atomic configuration and catalytic active sites, opens a new avenue for the development of solar-driven water splitting.

The formation of a functional blood vessel network relies on the ability of endothelial cells (ECs) to dynamically rearrange their adhesive contacts in response to blood flow and guidance cues, such as vascular endothelial growth factor-A (VEGF-A) and class 3 semaphorins (SEMA3s). Neuropilin 1 (NRP1) is essential for blood vessel development, independently of its ligands VEGF-A and SEMA3, through poorly understood mechanisms. Grounding on unbiased proteomic analysis, we report here that NRP1 acts as an endocytic chaperone primarily for adhesion receptors on the surface of unstimulated ECs. NRP1 localizes at adherens junctions (AJs) where, interacting with VE-cadherin, promotes its basal internalization-dependent turnover and favors vascular permeability initiated by histamine in both cultured ECs and mice. We identify a splice variant of tryptophanyl-tRNA synthetase (mini-WARS) as an unconventionally secreted extracellular inhibitory ligand of NRP1 that, by stabilizing it at the AJs, slows down both VE-cadherin turnover and histamine-elicited endothelial leakage. Thus, our work shows a role for NRP1 as a major regulator of AJs plasticity and reveals how mini-WARS acts as a physiological NRP1 inhibitory ligand in the control of VE-cadherin endocytic turnover and vascular permeability. ispartof: NATURE COMMUNICATIONS vol:13 issue:1 ispartof: location:England status: published

Recent studies show that user’s visual attention during virtual reality museum navigation can be effectively estimated with deep learning models. However, these models rely on large-scale datasets that usually are of high structure complexity and context specific, which is challenging for nonspecialist researchers and designers. Therefore, we present the deep learning model, ALRF, to generalise on real-time user visual attention prediction in virtual reality context. The model combines two parallel deep learning streams to process the compact dataset of temporal–spatial salient features of user’s eye movements and virtual object coordinates. The prediction accuracy outperformed the state-of-the-art deep learning models by reaching record high 91.03%. Importantly, with quick parametric tuning, the model showed flexible applicability across different environments of the virtual reality museum and outdoor scenes. Implications for how the proposed model may be implemented as a generalising tool for adaptive virtual reality application design and evaluation are discussed.

Sustainable energy storage system requires high-performance rechargeable batteries with earth-abundant elements and cost-effective electrodes. Prussian blue (PB) and its analogs (PBAs) are a large family of materials with open frameworks. Benefiting from nanoarchitectonics, the PBAs are receiving great attention as cathodic materials for various rechargeable batteries. In this review, we present a general summary and evaluation on the recent advances of PBAs for the rechargeable batteries applications. The general synthetic methods and the chemical properties of PBAs have also been discussed. This review aims to provide a brief outlook on the current and future research strategies of PBAs in the electrochemical energy storage.

Background Anti-angiogenic therapy has been shown to be a promising strategy for anti-tumor treatment. Increasing evidence indicates that tumor angiogenesis is affected by exosomes that are secreted by mesenchymal stem cells (MSCs), but whether exosomes derived from MSCs suppress or promote angiogenesis remain paradoxical. The purpose of this study focused on understanding the potential role of exosomes derived from stem cells of human deciduous exfoliated teeth (SHED-Exos) in regulating angiogenesis and the underlying molecular mechanism. Methods Exosomes were isolated from supernatants of SHED cells using an exosome purification kit and were characterized by transmission electron microscopy, nanoparticle tracking analysis and western blot analysis. Cell Counting Kit-8, flow cytometric assays, western blots, wound healing and transwell migration assays were performed to characterize the roles of SHED-Exos on cell proliferation, apoptosis and migration of human umbilical vein endothelial cells (HUVECs). The anti-angiogenic activity of SHED-Exos was assessed via a tube formation assay of endothelial cells and angiogenesis-related factors were analyzed by western blotting. In vivo, we used the chick chorioallantoic membrane (CAM) assay and an oral squamous cell carcinoma (OSCC) xenograft transplantation model with nude mice that received multi-point injections at three-day intervals to evaluate the effects on angiogenesis. Furthermore, the sequencing of microRNAs (miRNAs) in SHED-Exos was performed to investigate the underlying anti-angiogenic mechanism. Results The results showed that SHED-Exos inhibit cell proliferation and migration and induce apoptosis in HUVECs. SHED-Exos suppress the tube-like structure formation of HUVECs in vitro. SHED-Exos downregulate several angiogenesis-related factors, including VEGFA, MMP-9 and ANGPT1. In vivo, the chick CAM assay verified that treatment with SHED-Exos inhibits micro-vascular formation, and importantly, significantly reduces the micro-vascular formation of tumors generated from xenografted OSCC cells, which was associated with the inhibition of tumor growth in vivo. Mechanistically, our data suggested that SHED-Exos are enriched with miR-100-5p and miR-1246 and are transferred to endothelial cells, which results in decreased tube formation via the down-regulation of VEGFA expression. Conclusions These results demonstrate that SHED-Exos inhibit angiogenesis in vitro and in vivo, which suggests that SHED-Exos could potentially serve as a novel and effective therapeutic approach for anti-angiogenic treatment.

The structures and energetics of the binuclear phospholyl vanadium carbonyls (C4H4P)2V2(CO)n (n = 7, 6, 5, 4, 3, 2, 1) have been investigated using density functional theory. The lowest energy heptacarbonyl (C4H4P)2V2(CO)7 structures resemble those of the dimanganese pentacarbonyl (C4H4P)2Mn2(CO)5 with one seven-electron donor bridging η5,η1-C4H4P ring and no direct vanadium–vanadium bond. Similarly, the lowest energy hexacarbonyl (C4H4P)2V2(CO)6 structure resembles that of the dimanganese tetracarbonyl (C4H4P)2Mn2(CO)4 with two seven-electron donor bridging η5,η1-C4H4P rings and no direct vanadium–vanadium bond. The lowest energy pentacarbonyl (C4H4P)2V2(CO)5 structure has terminal η5-C4H4P phospholyl rings and a formal V≡V triple bond of length ~ 2.45 A similar to the experimentally known and structurally characterized cyclopentadienyl analogue (η5-C5H5)2V2(CO)5. Various combinations of V=V double bonds or V≡V triple bonds, four-electron donor bridging carbonyl groups and seven-electron donor bridging η5,η1-C4H4P rings are found in the more highly unsaturated derivatives (C4H4P)2V2(CO)n (n = 4, 3, 2) to give 17- and 18-electron vanadium configurations for triplet- and singlet-state structures, respectively. Formal V≣V quadruple bonds are found only in the highly unsaturated lowest energy singlet (C4H4P)2V2(CO)n (n = 2, 1) structures, which, however, lie at somewhat higher energies than isomeric triplet structures.

The structures of the lowest and a few higher isomers for Ru2Fn (n = 1–10) clusters are obtained based on functional B3P86 with 6–311 + g(d) for fluorine and LANL2DZ for ruthenium. The results show that Ru2Fn (n = 5–10) clusters investigated represent superhalongens characterized by the vertical electron affinity energies (VEA) significantly exceeding 3.8 eV. The VEA values estimated for the Ru2F5, Ru2F6, Ru2F7, Ru2F8, Ru2F9, and Ru2F10 systems are predicted to be 3.8 eV, 4.5 eV, 5.7 eV, 6.0 eV, 6.1 eV, and 6.8 eV. The stabilities of the lowest isomers for Ru2Fn (n = 5–10) and the chemical bonds between the two metal atoms are analyzed. The energy gap, vibration frequency, vertical electron affinity energy, vertical ionization energy and frontier molecular orbitals of these Ru2Fn clusters are also calculated. The spin polarization of Ru2Fn clusters originate mainly from Ru 4d orbitals, which determines the magnetism of the systems.

Zn-based two-dimensional layer coordination framework was synthesized by ionothermal synthesis and its solid-to-solid phase transition was studied by X-ray diffraction, solid state nuclear magnetic resonance and impedance spectroscopy. The phase transition is originated from the order-to-disorder behavior of accommodated ammonium cations in the structure. It occurs rapidly and reversibly, and little volume change and high thermal stability were observed.