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In this study, the Lewis doping approach of polyaniline (PANI) was employed to fabricate cobait–nitrogen–carbon (Co-N-C) oxygen electrocatalysts for Zn–air batteries, aiming to enhance the active spots of Co-N-C. This resulting Co-N-C catalysts exhibited well-defined nanofiber networks, and the Brunauer-Emmett-Teller (BET) analysis confirmed their substantial specific surface area. Electrochemical experiments demonstrated that the Co-N-C catalysts achieved the half-wave potential (vs. RHE) of 0.85 V in alkaline medium, overcoming Pt/C and iron–nitrogen–carbon (Fe-N-C) counterparts in extended cycle testing with only a 25 mV change in a half-wave potential after 5000 cycles. Remarkably, the highest power density measured in the zinc (Zn)–air battery reached 227 mW/cm2, a significant improvement over the performance of 101 mW/cm2 of the platinum on activated carbon (Pt/C) catalyst. These findings highlight the advantageous stability enhancement associated with the utilization of Co in the Co-N-C catalysts. [ABSTRACT FROM AUTHOR]

In recent years, non-noble metal catalysts such as Fe–N–C have received a lot of interest due to their excellent oxygen reduction (ORR) activity. However, the active sites of Fe–N–C still need to be further improved. Here, by adopting Lewis doping and double nitrogen source strategies to increase the density of accessible active sites, the catalyst exhibits excellent ORR activity. The ORR half-wave potential (E1/2) in 0.1 mol/L KOH solution can reach 0.92 V (vs. RHE), and the maximum power density of the Zn–air battery with Fe–N–C@MA-950 as the air electrode can reach 220 mW cm−2. The strategies provide a novel approach to the design of carbon-based catalysts for efficient energy conversion. [ABSTRACT FROM AUTHOR]

Healing of the cutaneous wound requires macrophage recruitment at the sites of injury, where chemotactic migration of macrophages toward the wound is regulated by local inflammation. Recent studies suggest a positive contribution of DNA methyltransferase 1 (Dnmt1) to macrophage pro-informatory responses; however, its role in regulating macrophage motility remains unknown. In this study, myeloid-specific depletion of Dnmt1 in mice promoted cutaneous wound healing and de-suppressed the lipopolysaccharides (LPS)-inhibited macrophage motility. Dnmt1 inhibition in macrophages eliminated the LPS-stimulated changes in cellular mechanical properties in terms of elasticity and viscoelasticity. LPS increased the cellular accumulation of cholesterol in a Dnmt1-depedent manner; cholesterol content determined cellular stiffness and motility. Lipidomic analysis indicated that Dnmt1 inhibition altered the cellular lipid homeostasis, probably through down-regulating the expression of cluster of differentiation 36 CD36 (facilitating lipid influx) and up-regulating the expression of ATP-binding cassette transporter ABCA1 (mediating lipid efflux) and sterol O-acyltransferase 1 SOAT1 (also named ACAT1, catalyzing the esterification of cholesterol). Our study revealed a Dnmt1-dependent epigenetic mechanism in the control of macrophage mechanical properties and the related chemotactic motility, indicating Dnmt1 as both a marker of diseases and a potential target of therapeutic intervention for wound healing. [ABSTRACT FROM AUTHOR]

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Detailed analysis the disparity and reduction potential of clinker emission factors at the provincial level is important for regional reduction policies. Using the surveyed data from 185 new suspension and pre-heater (NSP) process lines and 69 shaft kiln lines, this study firstly analyzed the disparity in emission factors based on production process, production scale, and regional distribution in 2015. We found that the emission factor of the shaft kiln process (898.24 kg/t) is higher than that of the NSP process (858.59 kg/t), and that small-scale production lines have higher emission factors than large-scale lines both for the two process. China's clinker emission factors increase from the eastern to the western regions. Then, we estimated the reduction potential of structural adjustment, raw material substitution, and energy saving and fuel substitution in regional emission factors by 2030. The result shows that emission factors of the surveyed provinces will decrease by 101.41–174.60 kg/t compared to the values in 2015, which mainly contributes by energy saving and fuel substitution (65.98%), and raw material substitution (25.72%). And structural adjustment contributes only a small part reduction for most investigated provinces. The national average emission factor is estimated to be 715.33 kg/t in 2030, which indicates a reduction of 16.65%. These results can provide valuable feedback to government officials on the effectiveness of existing measures and also serve as a reference for future decisions on emission reduction polices. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) reconstruction of objects and scenes from camera images is of great interests due to its wide applications. Reconstruction based on feature point correspondence is an established approach. Existing research on curve-based reconstruction is limited to certain type of curves and constrained by case-dependent reconstruction accuracy. In view of that, this paper developed a new method to reconstruct general 3D curves from stereo images. Under proposal, a B-spline curve fitting is applied to sets of 2D edge points extracted from acquired stereo images. Derived approximating parametric curves are then used to construct conic surfaces. Further, robust iterative algorithms are developed to get intersection of corresponding conic surfaces to recover 3D curve. Due to the method design, proposed approach can reconstruct general 3D curves including both open and closed curves. The curve fitting technique and developed robust algorithms can meet accuracy requirement of many real applications. Validity of the proposed method is verified through experiments on a cylinder and teacup in laboratory and a real forging within a workshop. [ABSTRACT FROM AUTHOR]

The prediction of PM2.5 concentrations with high spatiotemporal resolution has been suggested as a potential method for data collection to assess the health effects of exposure. This work predicted the weekly average PM2.5 concentrations in the Yangtze River Delta, China, by using a spatio-temporal model. Integrating land use data, including the areas of cultivated land, construction land, and forest land, and meteorological data, including precipitation, air pressure, relative humidity, temperature, and wind speed, we used the model to estimate the weekly average PM2.5 concentrations. We validated the estimated effects by using the cross-validated R2 and Root mean square error (RMSE); the results showed that the model performed well in capturing the spatiotemporal variability of PM2.5 concentration, with a reasonably large R2 of 0.86 and a small RMSE of 8.15 (μg/m3). In addition, the predicted values covered 94% of the observed data at the 95% confidence interval. This work provided a dataset of PM2.5 concentration predictions with a spatiotemporal resolution of 3 km × week, which would contribute to accurately assessing the potential health effects of air pollution. [ABSTRACT FROM AUTHOR]

Much attention is being given to estimating cement-related CO emissions in China. However, scant explicit and systematical exploration is being done on regional and national CO emission volumes. The aim of this work is therefore to provide an improved bottom-up spatial-integration system, relevant to CO emissions at factory level, to allow a more accurate estimation of the CO emissions from cement production. Based on this system, the sampling data of cement production lines were integrated as regional- and national-level information. The integration results showed that each ton of clinker produced 883 kg CO, of which the process, fuel, and electricity emissions accounted for 58.70%, 35.97%, and 5.33%, respectively. The volume of CO emissions from clinker and cement production reached 1202 Mt and 1284 Mt, respectively, in 2013. A discrepancy was identified between the clinker emission factors relevant to the two main production processes (i.e., the new suspension preheating and pre-calcining kiln (NSP) and the vertical shaft kiln (VSK)), probably relevant to the energy efficiency of the two technologies. An analysis of the spatial characteristics indicated that the spatial distribution of the clinker emission factors mainly corresponded to that of the NSP process. The discrepancy of spatial pattern largely complied with the economic and population distribution pattern of China. The study could fill the knowledge gaps and provide role players with a useful spatial integration system that should facilitate the accurate estimation of carbon and corresponding regional mitigation strategies in China. [ABSTRACT FROM AUTHOR]

Long-term application of mineral fertilizers might have adverse effects on soil quality and crop yield, which can be alleviated by biochar-based organic fertilizer (BOF) amendment that has been considered a potential strategy for improving soil quality and crop yields. Therefore, this study was conducted to explore the effects of partial substitution of mineral fertilizer with BOF on the yield and sugar content of sugar beet and to investigate whether such effects are correlated with the changes in photosynthesis, nitrogen assimilation, and sucrose synthesis. Five treatments, including one mineral fertilizer (CK) and four different application rates of BOF + inorganic nitrogen fertilizer, assigned as (B1), (B2), (B3), and (B4) treatments, were used. The total N, P2O5, and K2O contents for each treatment were equal, and their deficiency in the converter was overcome by mineral fertilizers. Compared with BOF, mineral fertilizer promoted sugar beet growth at 60 days after sowing (DAS). After 85 DAS, however, BOF enhanced photosynthetic pigment synthesis and photosystem II (PSII) activity, caused the delayed leaf senescence, and increased the amount of nitrogen assimilated and the capacity for sucrose synthesis in sugar beet leaves. Moreover, the B4 treatment significantly increased the soil nitrate-nitrogen content at the 100–200 cm soil depth and also the risk of leaching. The recommended optimal fertilization treatment was 3.25 t ha–1 BOFs + 50 kg ha–1 N + 25 kg ha–1 P2O5 + 25 kg ha–1 K2O (the B3 treatment). [ABSTRACT FROM AUTHOR]