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To characterize focal biomechanical alterations in subclinical keratoconus (SKC) using motion-tracking (MT) Brillouin microscopy and evaluate the ability of MT Brillouin metrics to differentiate eyes with SKC from normal control eyes. Prospective cross-sectional study. Thirty eyes from 30 patients were evaluated, including 15 eyes from 15 bilaterally normal patients and 15 eyes with SKC from 15 patients. All patients underwent Scheimpflug tomography and MT Brillouin microscopy using a custom-built device. Mean and minimum MT Brillouin values within the anterior plateau region and anterior 150 μm were generated. Scheimpflug metrics evaluated included inferior–superior (IS) value, maximum keratometry (K max), thinnest corneal thickness, asymmetry indices, Belin/Ambrosio display total deviation, and Ambrosio relational thickness. Receiver operating characteristic (ROC) curves were generated for all Scheimpflug and MT Brillouin metrics evaluated to determine the area under the ROC curve (AUC), sensitivity, and specificity for each variable. Discriminative performance based on AUC, sensitivity, and specificity. No significant differences were found between groups for age, sex, manifest refraction spherical equivalent, corrected distance visual acuity, K max , or KISA% index. Among Scheimpflug metrics, significant differences were found between groups for thinnest corneal thickness (556 μm vs. 522 μm; P < 0.001), IS value (0.29 diopter [D] vs. 1.05 D; P < 0.001), index of vertical asymmetry (IVA; 0.10 vs. 0.19; P < 0.001), and keratoconus index (1.01 vs. 1.05; P < 0.001), and no significant differences were found for any other Scheimpflug metric. Among MT Brillouin metrics, clear differences were found between control eyes and eyes with SKC for mean plateau (5.71 GHz vs. 5.68 GHz; P < 0.0001), minimum plateau (5.69 GHz vs. 5.65 GHz; P < 0.0001), mean anterior 150 μm (5.72 GHz vs. 5.68 GHz; P < 0.0001), and minimum anterior 150 μm (5.70 GHz vs. 5.66 GHz; P < 0.001). All MT Brillouin plateau and anterior 150 μm mean and minimum metrics fully differentiated groups (AUC, 1.0 for each), whereas the best performing Scheimpflug metrics were keratoconus index (AUC, 0.91), IS value (AUC, 0.89), and IVA (AUC, 0.88). Motion-tracking Brillouin microscopy metrics effectively characterize focal corneal biomechanical alterations in eyes with SKC and clearly differentiated these eyes from control eyes, including eyes that were not differentiated accurately using Scheimpflug metrics. Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article. [ABSTRACT FROM AUTHOR]

Matrix completion, aiming at restoring a low-rank matrix from observed entries, indicates the connection with the subspace clustering due to the low-rank property. However, it is expensive to incorporate subspace learning into the pervasive surrogate of matrix completion, the nuclear norm. In this paper, we design an orthogonal subspace exploration model for matrix completion, which can be easily integrated due to the succinct formulation. Then, we propose a non-convex surrogate with tractable solutions for low-rank matrix completion, so that the subspace exploration can be performed simultaneously. Compared with the existing surrogates (e.g. , nuclear norm, Schatten- p norm, max norm, etc.), the proposed surrogate is differential such that the optimization is still simple even after the subspace exploration is incorporated. Although the surrogate is non-convex, a parameter-free algorithm that is proved to converge into the global optimum is developed. The optimization consists of closed-form solutions so that the orthogonal subspace exploration will not distinctly bring additional costs and the algorithm empirically converges within dozens of iterations. Experiments illustrate the efficiency and superiority of our model. • A tractable orthogonal subspace exploration is designed for matrix completion. • A smooth non-convex surrogate is proposed to replace the classic nuclear norm. • The optimization is proved to converge into the global minimum. • The optimization of surrogate usually converges within dozens of iterations. • The surrogate is expandable so it is still fast with additionl subspace exploration. [ABSTRACT FROM AUTHOR]

In this paper, we report the energy transfer mechanism between Dy3+ ions as well as a new optical ratiometric thermometry strategy in Dy3+ doped CaWO 4 (CaWO 4 :Dy) phosphors. The optimal Dy3+ doping concentration was determined and the electric dipole-dipole interaction among Dy3+ was investigated based on the analysis of the concentration-dependence luminescent properties in CaWO 4 :Dy phosphors. The photoluminescence (PL) of two blue and two yellow emissions produced by Dy3+ transitions from the thermally coupled energy levels (TCLs) of 4I 15/2 /4F 9/2 to the 6H 15/2 ground level and 4I 13/2 metastable level, respectively, exhibited opposite PL behavior with increasing temperature. The luminescence intensity ratio (LIR) between blue and yellow emissions (B/Y) was discovered to have a quantitative relationship with temperature based on the classic thermalized population distribution of TCLs. In comparison to traditional thermometry based on the LIR of two blue emissions, the proposed new ratiometric thermometry based on the LIR of B/Y demonstrated good optical thermometry behavior with extended temperature detection range to cryogenic region, excellent absolute sensitivity, good repeatability, and high accuracy, which can also be applied to other Dy3+ doped materials such as Y 3 Al 5 O 12 and NaYF 4 phosphors using either down- or up-conversion PL of blue and yellow emissions. [ABSTRACT FROM AUTHOR]

The global outbreak of the COVID-19 pandemic has slowed down international investment and trade, and partially disrupted the global supply chain. This paper provides an overview of the findings in 80 scholarly articles from recent years, comprehensively summarises and analyzes the research on international capital flows and global value chain（GVC）reconstruction, and deeply reveals the impact of COVID-19 on OFDI, the change of OFDI performance before and after the pandemic and factors that may accelerate GVC reconstruction in the future. We identify research gaps in a combination of OFDI and GVC reconstruction at both the macro and micro level and suggest several future research topics such as political risk and bilateral relations factors, the role of China in OFDI and GVC dynamics, network and OFDI performance, network characteristics of GVC reconstruction, OFDI and GVC reconstruction. [ABSTRACT FROM AUTHOR]

Prolonged and intricate trade frictions existed between China and the US, which grew more and more intense during Trump's presidency. Indicators of US anti-dumping policies against China of Temporary Trade Barrier Database (TTBD) from 2000 to 2014 and the global value chains indexes proposed by Wang et al. were adopted in this article to explore the impacts of such policies on China's manufacturing global value chains status. The results showed that US anti-dumping against China policies shortened the backward linkage based production length at a faster speed, which resulted in a relatively upstream movement of the production line position in China. Ultimately, it enhanced the status of Chinese manufacturing in the global value chains. Therefore, China should continue the open-up policy and strengthen its interconnections with world economy to obtain a broader and more sustainable growing prospect. [ABSTRACT FROM AUTHOR]

The increasing demand for ecosystem services in regional development has presented significant challenges to environmental sustainability. To alleviate environmental pressure, it is crucial to employ the provincial ecological footprint to gauge regional ecological pressure and research the determinants that contribute to reducing environmental pressure. This underscores the significance of examining and addressing the intricate relationships between ecological resources and regional development. While prior studies often focus on national data, provincial ecological footprints have been relatively ignored. Moreover, scant research exists on the influence of variables such as resource rents and industrial structures. This study employs the ecological footprint model to assess the per capita ecological footprint of Chinese provinces from 1990 to 2020, intending to gauge escalating ecological pressures and pinpoint their drivers. We use spatial panel data analysis to investigate the association among economic growth, natural resource rents, industrial structures and ecological footprint. Leveraging spatial weight matrices, we detected provincial footprint spatial autocorrelation and further analyzed it using the spatial Durbin model. Results underscore that economic growth profoundly shapes the ecological footprint, but an explicit Environmental Kuznets Curve remains elusive. Both natural resource rents and industrial shifts considerably influence the ecological footprint. Distinguishing from earlier non-spatial studies, our research merges spatial panel data analysis, emphasizing the regulatory role of juxtaposing natural resource rents with industrial structure adjustment can decrease the impact of economic growth on the ecological footprint. Advocating robust policies that favor renewables over non-renewables is pivotal, emphasizing the imperative for rigorous environmental standards in sectors shifting to renewables. [ABSTRACT FROM AUTHOR]

Electrode material is the core component of electrochemical sensor, which has a decisive influence on the detection performance of heavy metal ions. A novel electrochemical sensor based on amino modified metal-organic frameworks loaded three-dimensional carbon nanofiber aerogel composite material was proposed. The UiO-66-NH 2 was embedded into nanofibers through one-step electrospinning technology to forming a legume-like structure, ensuring the number of active sites N coordination with HMIs, which improved enrichment capacity of the sensor. 3D carbon nanofiber aerogel with multistage pore structure was developed by one-dimensional nanofibers as unit modules, which increases conductive path and HMIs transport channel. Accordingly, the UiO-66-NH 2 @carbon nanofiber aerogel modified electrode (N-U@CFA/GCE) as an electrochemical sensor exhibited an ultra-high sensitivity and the low limit of detection for the simultaneous detection of Cd2+ (0.52 nM) and Pb2+ (0.46 nM) using the differential pulse anode stripping voltammetry and was feasible and accurate for the detection of actual environmental water. The novel sensor platform has high sensitivity, stability and anti-interference, which showing great potential on HMIs monitoring. [Display omitted] • The UiO-66-NH 2 was embedded into carbon nanofibers affording to a legume-like structure. • The multistage pore structure carbon aerogel had abundant enrichment sites and network conductive paths. • The novel sensor exhibited an ultra-high sensitivity and the low LOD for detection of Cd2+ and Pb2+. [ABSTRACT FROM AUTHOR]

Abstract The search of multifunctional epoxy nanocomposites with both strength and toughness combined with smart features such as electrical conductivity is essential in design of advanced materials. In this work, by utilizing a binary nanofiller strategy, both strength and toughness as well as high electrical conductivity are obtained in epoxy with trace nanopolystyrene grafted with epichlorohydrin (nano g -PS) to facilitate the dispersion of multi-walled carbon nanotubes (MWCNTs). The increased tensile strength (37.6%) and flexural strength (34.4%) are acquired in nano g -PS (0.0677 vol%)/MWCNTs (0.0335 vol%)/epoxy in contrast to pure epoxy. A remarkably improved tensile toughness up to 379.2% and an increased elongation at break up to 208.3% are obtained in this epoxy nanohybrid. The synergistic interactions among nano g -PS, MWCNTs and epoxy matrix as well as the state transition of nano g -PS from glassy state to fluid state provide an improved dispersion of nanofillers which is responsible for the increased electrical conductivity and enhanced mechanical properties. The decreased surface resistivity allows these nanohybrids to sufficiently dissipate surface charges as an antistatic material. This work provides an effective way to disperse carbon nanotubes with small amount of thermoplastic PS to simultaneously strengthen and toughen the thermosetting epoxy while introducing highly conductive function. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Highlights • The controlling effect of three catch crops (sweet corn, amaranth and sweet sorghum) on nitrate leaching was evaluated. • The fate of N due to three catch crops was simulated via the WHCNS model. • Three catch crops significantly reduced N leaching during the summer fallow season. • Amaranth was recommended to reduce negative environmental impacts. Abstract Chinese intensive greenhouse vegetable systems are characterized by high input of water and nutrients, which are not sustainable. There is an urgent need to explore smart and practical strategies to convert the "high input-low output" systems to "optimal input-output" ones. This study aimed to evaluate the effects of different catch crops on reducing nitrate leaching in the vegetable greenhouse during the summer fallow season. A two-year field experiment with three catch crops, i.e., sweet corn (SC), amaranth (A) and sweet sorghum (SG), and no catch crop (CK) were conducted in vegetable greenhouse in Dingzhou city, Hebei province, China. The measured soil water content and inorganic nitrogen (N) content in soil profile, biomass and crop N uptake were used to validate the WHCNS (Soil Water Heat Carbon Nitrogen Simulator) model, soil water movement and nitrate leaching were simulated. The results showed that the catch crops decreased the water drainage by 18.2–29.0% and nitrate leaching by 23.3–42.3% respectively, compared with CK. The water drainage reduction ranked as SC > SG > A, while the nitrate leaching reduction was A > SC > SG. The biomass was SC > SG > A, while the crop N uptake was SC > A > SG. Sweet corn could absorb the residual nitrate in the deep soil layers due to the long root system, while amaranth could absorb most residual nitrate in the surface soil. Amaranth showed greater N-uptake capacity than sweet corn, and the nitrate was mainly accumulated in the surface soil. Planting amaranth as summer catch crop reduced nitrate leaching in the vegetable greenhouses. Our study provides a guideline for selecting effective catch crops in intensive vegetable greenhouses in North China. [ABSTRACT FROM AUTHOR]

In this work, a nanocarbon bridged nanomagnetite network (NC-NMN) is developed through the electrospinning of epichlorohydrin functionalized polystyrene ( f -PS), followed by the direct calcination of f -PS and ferric nitrate, which is capable of superfast removing hexavalent chromium (Cr(VI)) from polluted water within only 15 s benefiting from its gridding framework, with an adsorption rate constant of 1.64 g mg −1  min −1 according to the pseudo-second-order kinetics. The well-fitted Langmuir isotherm model indicates a monolayer adsorption for Cr(VI) on NC-NMN. The thermodynamic parameters including negative Δ G ° and positive Δ H ° demonstrate that the Cr(VI) adsorption on NC-NMN is spontaneous and endothermic. The Cr(VI) adsorption retention, which is only 3.8%, is achieved for NC-NMN after five cycles, exhibiting a prominent stability and an excellent recyclability. X-ray photoelectron spectroscopy (XPS), zeta potential and energy-filter transmission electron spectroscopy (EFTEM) results illustrate that both the electrostatic attraction and the network structure of NC-NMN are responsible for the superior Cr(VI) adsorption performance. This work intends to provide a new method for designing the novel structure materials for polluted water treatment. [ABSTRACT FROM AUTHOR]

At room temperature, a large negative out-of-plane magnetoresistance (MR), [ R ( H )- R (0)]/ R (0), with a value of −35.76% at magnetic field of 9 T has been obtained in the cobalt ferrite (CoFe 2 O 4 )/polyaniline (PANI) nanocomposites with CoFe 2 O 4 loading of 40.0 wt% prepared by surface initiated polymerization (SIP) method, which is strongly related to the weak localization (WL) model in the weak disordered system. The negative MR at room temperature in the CoFe 2 O 4 /PANI nanocomposites exhibits the obvious nanoparticle loading and magnetic field dependent properties. Both thermal activated transport model and Mott variable range hopping (VRH) model are applied to express the electrical transport mechanism for the temperature regimes of 180–290 K and 50–180 K, accordingly. The electrical transport in the CoFe 2 O 4 /PANI nanocomposites obeys the 3D VRH transport mechanism at low temperature range of 50–180 K. The estimated activation energy E g for the CoFe 2 O 4 /PANI nanocomposites with different CoFe 2 O 4 nanoparticle loadings of 10.0, 20.0, 40.0, and 60.0 wt% is 61, 63, 65, and 87 meV, respectively. The coating of PANI on the surface of CoFe 2 O 4 nanoparticle reveals the significant effect on both the remanence and coercivity of CoFe 2 O 4 nanoparticle. [ABSTRACT FROM AUTHOR]

Chondrosarcomas are the most common malignancy of cartilage and are associated with somatic mutations in isocitrate dehydrogenase 1 (IDH1) and IDH2 genes. Somatic IDH mutations are also found in its benign precursor lesion, enchondromas, suggesting that IDH mutations are early events in malignant transformation. Human mutant IDH chondrosarcomas and mutant Idh mice that develop enchondromas investigated in our studies display glycogen deposition exclusively in mutant cells from IDH mutant chondrosarcomas and Idh1 mutant murine growth plates. Pharmacologic blockade of glycogen utilization induces changes in tumor cell behavior, downstream energetic pathways, and tumor burden in vitro and in vivo. Mutant IDH1 interacts with hypoxia-inducible factor 1α (HIF1α) to regulate expression of key enzymes in glycogen metabolism. Here, we show a critical role for glycogen in enchondromas and chondrosarcomas, which is likely mediated through an interaction with mutant IDH1 and HIF1α. [Display omitted] • Mutant IDH chondrosarcomas and mutant Idh1 mice harbor elevated levels of glycogen • Glycogen fuels tumor growth and downstream energetic pathways • Gys1 deletion reduces enchondroma-like lesion formation in mutant Idh1 mice • HIF1α and mutant IDH1 interact to regulate glycogen metabolism in tumor cells Pathmanapan et al. show a role for glycogen stores in tumor growth and benign lesion formation in mutant IDH1 human chondrosarcomas and in a mutant Idh1 murine model of enchondroma development. Regulation of glycogen metabolism was shown to be mediated through an interaction with mutant IDH1 and HIF1α. [ABSTRACT FROM AUTHOR]