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Both the realization of the "double carbon" goal and the low-carbon economy development requires a focus on transportation CO2 emissions. Calculating Chinese transportation CO2 emissions and exploring its principles are essential for achieving high-quality development of the transportation industry. Firstly, we use a "top-down" method to assess carbon emissions from transportation operations from 2003 to 2019. Secondly, the study decomposes the influencing factors of transportation CO2 emissions in China using the log-average weight decomposition method. Thirdly, the Tapio decoupling model is applied to study the decoupling effect of transportation CO2 emissions in each province of China. The findings suggest that China's transport carbon emissions are growing at an annual rate of roughly 16%. All GDP per capita, transportation energy intensity, and population size increase the growth of transportation CO2 emissions. Contrastly, energy use per unit of turnover and transportation intensity decrease the growth of transportation CO2 emissions. There is much variation in China's carbon emission decoupling index from year to year. Policy recommendations are proposed in response to the study of the above findings and the differences in carbon reduction potential among provinces. [ABSTRACT FROM AUTHOR]

The correlation between the internal calice arrangement and compressive behavior of the skeleton of coral Pocillopora verrucosa has been characterized. The internal calices of this skeleton are arranged radially from a central axis in each branch. Such an arrangement of the calices results in a gradient distribution of the compressive properties; the middle part provides a higher strength, and the marginal part of the coral branch can undergo larger deformation to a certain extent. That is to say, the coral skeleton can offer a stronger internal support and a tougher external layer. Thus, the coral skeleton, as a natural porous and mineral material, can effectively undergo the ocean currents and provides a sturdy framework to protect the living polyps. [ABSTRACT FROM AUTHOR]

Manganese oxides (MnOx) as potential anode materials need support by porous carbonaceous materials to avoid its large volume change, pulverization and poor conductivity during lithiation and delithiation. However, the homogeneous distribution of MnOx particles onto graphene sheets (rGO) is still questionable, because both components have different densities and activity in solution. Freeze-drying technique has gained remarkable attention for the fabrication of porous nanocomposites. In this work, a homogeneous nanocomposite of MnOx/rGO is successfully synthesized by freeze-drying technique compared with MnOx/rGO sample synthesized by traditional drying method, and MnrGO-FD sample exhibits an improved rate performance and cyclic performance. It delivers 1446.4 mAh g−1 with Coulombic efficiency (CE) of 70.4% at the initial cycle and remains 1246.6 mAh g−1 with CE of 98.6% after 150 cycles at 0.1 A g−1. Moreover, it delivers capacity of 729.1 mAh g−1 with CE of 99.3% at 1 A g−1 for 300 cycles. Benefiting from freeze-drying, MnOx nanoparticles are distributed on porous graphene framework and graphene buffers the volume expansion of MnOx and provides conductive channels between electrolyte and active materials. [ABSTRACT FROM AUTHOR]

Introduction: The effect of dipeptidyl peptidase-4 (DDP-4) inhibitors versus α-glucosidase inhibitors (AGIs) on the treatment of type 2 diabetes mellitus (T2DM) in a real-world setting is unknown. The aim of this real-world study was to compare the glucose-lowering effect and tolerability of vildagliptin as add-on to metformin monotherapy (VM) and AGI as add-on to metformin monotherapy (AM) in Chinese patients with T2DM. Methods: This was a subgroup analysis of the China Prospective Diabetes Study, a post-marketing, prospective, observational, real-world study conducted at 52 centers in China. T2DM patients with inadequate glycemic control on metformin monotherapy who received VM or AM were included. The composite primary endpoint was glycemic control (hemoglobin A1c [HbA1c] < 7%) after 12 months in the absence of tolerability events (hypoglycemia, weight gain ≥ 3%, or gastrointestinal events leading to treatment discontinuation). Propensity score matching (PSM) was used to balance the two groups. Results: The success rates of the composite endpoint were higher in the VM group (n = 604/159 before/after PSM) than in the AM group (n = 159/157 before/after PSM), but the difference was not statistically significant (before PSM: 53.0 vs. 46.5%, P = 0.148; after PSM: 56.7 vs. 45.9%, P = 0.055). The glycemic control rate and HbA1c reduction were similar between groups at 3, 6, and 12 months. Compared with the AM group, the VM group had lower risks of any tolerability event (relative risk [RR] 0.53, 95% confidence interval [CI] 0.33–0.83, P = 0.006), of any adverse event (AE) (RR 0.64, 95% CI 0.41–1.00, P = 0.049), and of any serious AE (RR 0.45, 95% CI 0.25–0.81, P = 0.007). Conclusion: The results of this real-world study suggest that vildagliptin as add-on to metformin monotherapy had a similar glucose-lowering effect to AGI as add-on to metformin monotherapy, but with better safety. [ABSTRACT FROM AUTHOR]

3D nanohybrid structures with few-layered MoS2 nanosheets uniformly incorporated in the carbon substrate are prepared via using the rapid and homogeneous microwave-hydrothermal method, in which the size of the basic unit structure of MoS2/C was small. The samples were systematically investigated by X-ray diffraction, field emission scanning electron microscopy, X-Ray photoelectron spectroscopy and high-resolution transmission electron microscopy for structure and composition test. The electrochemical performances of the composites are evaluated by cyclic voltammogram, galvanostatic charge-discharge and electrochemical impedance spectroscopy. Electrochemical measurements reveal that the maximum-specific capacitance of the MoS2/C electrodes reaches up to 1003 mAh g-1 at a discharge current density 100 mA g-1. The MoS2/C hybrid composite remains 755 mAh g-1 after 50 cycles at the current of 200 mA g-1, much higher than that of the pure MoS2. The superior electrochemical performances of MoS2/C composites as Li-ion battery anodes are attributed to their enhanced available active sites for charges, decreased transmission resistance between interlayers, improved electronic conductivity as well as good mechanical stability. [ABSTRACT FROM AUTHOR]

Natural structural materials with intricate hierarchical architectures over several length scales exhibit excellent combinations of strength and toughness. Here we report the mechanical response of a crossed-lamellar structure in Cymbiola nobilis shell via stepwise compression tests, focusing on toughening mechanisms. At the lower loads microcracking is developed in the stacked direction, and channel cracking along with uncracked-ligament bridging and aragonite fiber bridging occurs in the tiled direction. At the higher loads the main mechanisms involve cracking deflection in the bridging lamellae in the tiled direction alongside step-like cracking in the stacked direction. A distinctive crack deflection in the form of 'convex' paths occurs in alternative lamellae with respect to the channel cracks in the tiled direction. Furthermore, a barb-like interlocking mechanism along with the uneven interfaces in the 1st-order aragonite lamellae is also observed. The unique arrangement of the crossed-lamellar structure provides multiple interfaces which result in a complicated stress field ahead of the crack tip, hence increasing the toughness of shell. [ABSTRACT FROM AUTHOR]