Within the endogenous growth framework, we offer an explanation on how foreign direct investment (FDI) generates externalities in the form of technology transfer. We distinguish between the level and ...rate effects of spillovers on the productivity of domestic firms. A new insight gained from the theory is that the level and rate effects of spillovers can go in opposite directions. The negative level effect underscores the fact that technology transfer is a costly process—scarce resources must be devoted to learning. The positive rate effect indicates that technology spillovers enhance domestic firms' future productive capacity. Using a large panel of Chinese manufacturing firms, we find suggestive evidence that an increase in FDI at the four-digit industry level lowers the short-term productivity level but raises the long-term rate of productivity growth of domestic firms in the same industry. We also find that spillovers through backward and forward linkages between industries at the two-digit level have similar effects on the productivity of domestic firms, and backward linkages seem to be statistically the most important channel through which spillovers occur.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
To improve the animation design ability of animation aesthetics students and the teaching ability of teachers, this paper constructs an evaluation system of animation aesthetics education based on ...Internet+. Firstly, the feasibility of Internet+ education is analyzed, and the Kohonen grid is introduced to fuzzy classify the images and get the corresponding affiliation vector. Then the mean value method is used to fuse the two-dimensional images, and the evaluation index of animation aesthetics education is derived according to the gray value. Secondly, considering the limited capacity of the animation aesthetics education evaluation system, the principal component analysis method is used to calculate the feature values, weight percentages, etc., to filter out the range of index values and construct the evaluation system according to the main indexes. Finally, according to the scores of students’ animation works and teachers’ satisfaction before and after the platform was implemented, it was confirmed that the built platform could optimize the teaching effect. The results showed that after the teachers adjusted their teaching according to the evaluation system, the students’ work scored 90 and above, and the student’s satisfaction with the teachers increased from the highest 6.5 to 9.8, which optimized the teaching effect.
Coumarins are a very large family of compounds containing the unique 2H-chromen-2-one motif, as it is known according to IUPAC nomenclature. Coumarin derivatives are widely found in nature, ...especially in plants and are constituents of several essential oils. Up to now, thousands of coumarin derivatives have been isolated from nature or produced by chemists. More recently, the coumarin platform has been widely adopted in the design of small-molecule fluorescent chemosensors because of its excellent biocompatibility, strong and stable fluorescence emission, and good structural flexibility. This scaffold has found wide applications in the development of fluorescent chemosensors in the fields of molecular recognition, molecular imaging, bioorganic chemistry, analytical chemistry, materials chemistry, as well as in the biology and medical science communities. This review focuses on the important progress of coumarin-based small-molecule fluorescent chemosensors during the period of 2012–2018. This comprehensive and critical review may facilitate the development of more powerful fluorescent chemosensors for broad and exciting applications in the future.
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IJS, KILJ, NUK, PNG, UL, UM
DNA materials have emerged as potential nanocarriers for targeted cancer therapy to precisely deliver cargos with specific purposes. The short half‐life and low bioavailability of DNA materials due ...to their interception by the reticuloendothelial system and blood clearance further limit their clinical translation. This study employs an HER2‐targeted DNA‐aptamer‐modified DNA tetrahedron (HApt‐tFNA) as a drug delivery system, and combines maytansine (DM1) to develop the HApt‐DNA tetrahedron/DM1 conjugate (HApt‐tFNA@DM1, HTD, HApDC) for targeted therapy of HER2‐positive cancer. To optimize the pharmacokinetics and tumor‐aggregation of HTD, a biomimetic camouflage is applied to embed HTD. The biomimetic camouflage is constructed by merging the erythrocyte membrane with pH‐responsive functionalized synthetic liposomes, thus with excellent performance of drug delivery and tumor‐stimulated drug release. The hybrid erythrosome‐based nanoparticles show better inhibition of HER2‐positive cancer than other drug formulations and exhibit superior biosafety. With the strengths of precise delivery, increased drug loading, sensitive tumor probing, and prolonged circulation time, the HApDC represents a promising nanomedicine to treat HER2‐positive tumors. Notably, this study developsa dual‐targeting nanoparticle by combining pH‐sensitive camouflage and HApDC, initiating an important step toward the development and application of DNA‐based medicine and biomimetic cell membrane materials in cancer treatment and other potential biological applications.
A PEOz‐erythrosome vesicle loaded with HER2 aptamer‐DNA tetrahedron/maytansine conjugates (HApt‐tFNA@DM1, HTD) is developed for targeted delivery of the HApDCs to HER2‐positive cancer. The PEOz‐erythrosome@HTD prolongs the blood circulation of HTD, protects it from the early blood clearance, and then delivers and releases it into the tumor microenvironment, further improving the antitumor activity of HApDC.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
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•Propose an environmentally friendly integrated flowsheet for recycling cathode materials.•Detailed analysis of metal leaching behavior in different leaching systems.•Under ...H2SO4–C6H8O6 system, the leaching efficiency of Li, Co, Ni, and Mn all exceeded 99.5%.•98.96 of Ni, 99.57% of Mn, 99.76% of Co, and 89.81% of Li were recovered as C8H14N4NiO4, MnCO3, CoC2O4, and Li2CO3.
With increase in the number of scrapped portable electronics and new energy powered vehicles, the production of spent Li-ion batteries (LIBs) has increased progressively each year. Harmful substances in spent LIBs can pollute the environment and threaten human health. A sustainable technology should be developed to recycle the spent LIBs. Accordingly, a new environmentally friendly hydro-metallurgical process was proposed for leaching Li, Co, Ni, and Mn from spent LIBs using sulfuric acid with l-ascorbic acid as a reductant. Over the leaching process, several parameters, including sulfuric acid and l-ascorbic acid concentrations, solid to liquid ratio, temperature and time were systematically investigated. The maximum recovery efficiencies of Li, Co, Ni, and Mn were as high as 99.69%, 99.56%, 99.60%, and 99.87% under the optimized conditions (C(H2SO4 concentration) = 1.5 mol/L, C(C6H8O6 concentration) = 0.25 mol/L, the agitation speed was 300 r/min, the liquid–solid ratio was 15 mL/g, and the temperature was 333 K for 60 min), respectively. The synergistic mechanism was analyzed by X-ray diffraction, scanning electron microscopy, and Fourier-transform infrared spectroscopy of the structure of cathode materials, residues, and leachate. The analysis results indicate that the dissolution rate of Ni, Mn, and Co was significantly improved under the condition of adding l-ascorbic acid as a reducing agent. Finally, 98.96 of Ni, 99.57% of Mn, 99.76% of Co, and 89.81% of Li were recovered in the form of C8H14N4NiO4, MnCO3, CoC2O4, and Li2CO3 through precipitation-solvent extraction methods.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Excessive monocyte/macrophage activation with the development of a cytokine storm and subsequent acute lung injury, leading to acute respiratory distress syndrome (ARDS), is a feared consequence of ...infection with COVID‐19. The ability to recognize and potentially intervene early in those patients at greatest risk of developing this complication could be of great clinical utility. In this study, we performed flow cytometric analysis of peripheral blood samples from 34 COVID‐19 patients in early 2020 in an attempt to identify factors that could help predict the severity of disease and patient outcome. Although we did not detect significant differences in the number of monocytes between patients with COVID‐19 and normal healthy individuals, we did identify significant morphologic and functional differences, which are more pronounced in patients requiring prolonged hospitalization and intensive care unit (ICU) admission. Patients with COVID‐19 have larger than normal monocytes, easily identified on forward scatter (FSC), side scatter analysis by routine flow cytometry, with the presence of a distinct population of monocytes with high FSC (FSC‐high). On more detailed analysis, these CD14+CD16+, FSC‐high monocytes show features of mixed M1/M2 macrophage polarization with higher expression of CD80+ and CD206+ compared with the residual FSC‐low monocytes and secretion of higher levels of IL‐6, IL‐10, and TNF‐α, when compared with the normal controls. In conclusion, the detection and serial monitoring of this subset of inflammatory monocytes using flow cytometry could be of great help in guiding the prognostication and treatment of patients with COVID‐19 and merits further evaluation.
Graphical
The presence of larger monocytes with more mature macrophage phenotype in blood drives the dysregulation of immune response in COVID‐19.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
In many reactions restricted by water, selective removal of water from the reaction system is critical and usually requires a membrane reactor. We found that a simple physical mixture of hydrophobic ...poly(divinylbenzene) with cobalt-manganese carbide could modulate a local environment of catalysts for rapidly shipping water product in syngas conversion. We were able to shift the water-sorption equilibrium on the catalyst surface, leading to a greater proportion of free surface that in turn raised the rate of syngas conversion by nearly a factor of 2. The carbon monoxide conversion reached 63.5%, and 71.4% of the hydrocarbon products were light olefins at 250°C, outperforming poly(divinylbenzene)-free catalyst under equivalent reaction conditions. The physically mixed CoMn carbide/poly(divinylbenzene) catalyst was durable in the continuous test for 120 hours.
Channeling water away
Heterogeneous catalytic reactions that produce water as a by-product can be inhibited by its presence on the surface. Fang
et al
. found that for the production of light olefins from syngas (a 2:1 mixture of hydrogen and carbon monoxide) with a cobalt manganese carbide catalyst at 250°C, the addition of the hydrophobic polymer polydivinylbenzene as part of a physical mixture almost doubled the conversion of carbon monoxide (see the Perspective by Ding and Xu). Theoretical models suggest that the polymer formed channels that accelerated water diffusion away from the catalyst. —PDS
Mixing a hydrophobic polymer with a solid catalyst improves performance by accelerating the escape of product water.
A self‐equalized linear‐phase microstrip bandpass filter (BPF) utilizing negative group delay (NGD) parallel‐coupled three‐line (PCTL) units is presented in this letter. The NGD PCTL unit possesses ...an NGD valley in its frequency response of group delay (GD). By a combination of two or more NGD valleys, the sharp positive GD peaks at passband edges of a conventional coupled‐line BPF are counterbalanced, resulting in a linear phase response over the entire passband. A prototype of linear‐phase BPF in S‐band is designed by replacing two coupled‐line units in a three‐pole conventional BPF with the proposed NGD PCTL units. Measured passband GD fluctuation of the BPF utilizing NGD PCTL units is 0.5 ns while that of the BPF using conventional coupled‐line units is 1.7 ns, a considerable improvement of 70.5% is achieved with no increase in overall time delay. The out‐of‐band suppression is well retained, and the circuit size is 0.18 λg2.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Abstract
Membranes with fast and selective ions transport are highly demanded for energy storage devices. Layered double hydroxides (LDHs), bearing uniform interlayer galleries and abundant hydroxyl ...groups covalently bonded within two-dimensional (2D) host layers, make them superb candidates for high-performance membranes. However, related research on LDHs for ions separation is quite rare, especially the deep-going study on ions transport behavior in LDHs. Here, we report a LDHs-based composite membrane with fast and selective ions transport for flow battery application. The hydroxide ions transport through LDHs via vehicular (standard diffusion) & Grotthuss (proton hopping) mechanisms is uncovered. The LDHs-based membrane enables an alkaline zinc-based flow battery to operate at 200 mA cm
−2
, along with an energy efficiency of 82.36% for 400 cycles. This study offers an in-depth understanding of ions transport in LDHs and further inspires their applications in other energy-related devices.
Sepsis is a common critical condition caused by the body's overwhelming response to certain infective agents. Many biomarkers, including the serum lactate level, have been used for sepsis diagnosis ...and guiding treatment. Recently, the Third International Consensus Definitions for Sepsis and Septic Shock (Sepsis-3) recommended the Sequential Organ Failure Assessment (SOFA) and the quick SOFA (qSOFA) rather than lactate for screening sepsis and assess prognosis. Here, we aim to explore and compare the prognostic accuracy of the lactate level, the SOFA score and the qSOFA score for mortality in septic patients using the public Medical Information Mart for Intensive Care III database (MIMIC III).
The baseline characteristics, laboratory test results and outcomes for sepsis patients were retrieved from MIMIC III. Survival was analysed by the Kaplan-Meier method. Univariate and multivariate analysis was performed to identify predictors of prognosis. Receiver operating characteristic curve (ROC) analysis was conducted to compare lactate with SOFA and qSOFA scores.
A total of 3713 cases were initially identified. The analysis cohort included 1865 patients. The 24-h average lactate levels and the worst scores during the first 24 h of ICU admission were collected. Patients in the higher lactate group had higher mortality than those in the lower lactate group. Lactate was an independent predictor of sepsis prognosis. The AUROC of lactate (AUROC, 0.664 95% CI, 0.639-0.689) was significantly higher than that of qSOFA (AUROC, 0.547 95% CI, 0.521-0.574), and it was similar to the AUROC of SOFA (AUROC, 0.686 95% CI, 0.661-0.710). But the timing of lactate relative to SOFA and qSOFA scores was inconsistent.
Lactate is an independent prognostic predictor of mortality for patients with sepsis. It has superior discriminative power to qSOFA, and shows discriminative ability similar to that of SOFA.
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