With the challenge to reach targets of carbon emission reduction at the regional level, it is necessary to analyze the regional differences and influencing factors on China’s carbon emission ...efficiency. Based on statistics from 2005 to 2015, carbon emission efficiency and the differences in 30 provinces of China were rated by the Modified Undesirable Epsilon-based measure (EBM) Data Envelopment Analysis (DEA) Model. Additionally, we further analyzed the influencing factors of carbon emission efficiency’s differences in the Tobit model. We found that the overall carbon emission efficiency was relatively low in China. The level of carbon emission efficiency is the highest in the East region, followed by the Central and West regions. As for the influencing factors, industrial structure, external development, and science and technology level had a significant positive relationship with carbon emission efficiency, whereas government intervention and energy intensity demonstrated a negative correlation with carbon emission efficiency. The contributions of this paper include two aspects. First, we used the Modified Undesirable EBM DEA Model, which is more accurate than traditional methods. Secondly, based on the data’s unit root testing and cointegration, the paper verified the influencing factors of carbon emission efficiency by the Tobit model, which avoids the spurious regression. Based on the results, we also provide several policy implications for policymakers to improve carbon emission efficiency in different regions.
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•Rice husks were converted into activated carbon by KOH activation.•The highest specific surface area of porous carbon is as high as 3145m2g−1.•The highest gravimetric capacitance ...performance is 367Fg−1and 174Fg−1 in aqueous and organic electrolytes.•The rice husk supercapacitor shows excellent rate performance and cycling stability.
Rice husks were converted into activated carbon by KOH activation, at temperatures between 400 and 900°C and used in a two-electrode supercapacitor. The rice husks contain SiO2 nano-crystals surrounded by an amorphous carbon matrix. The activated carbons maintained their size and shape after the synthesis process and the ordering degree of carbon increased at elevated temperatures. The highest BET surface area of the activated carbons was around 3145m2g−1. Electrochemical properties of the studied samples were measured using a two electrode cell in 6M KOH and 1.5M tetraethylammonium tetrafluoroborate in acetonitrile. The material synthesized at 800°C showed the highest gravimetric capacitance performance of 367Fg−1and 174Fg−1 in aqueous and organic electrolytes, respectively. In contrast to the commercial activated carbons, rice husk activated carbon (RHAC), this material showed excellent high-power handling ability and electrochemical cycle performance, after 30000 cycles the capacitive value almost remained unchanged.
Plug-in electric vehicles (PEVs) appear to offer a promising option for mitigating greenhouse emission. However, uncoordinated PEV charging can weaken the reliability of power systems. The proper ...accommodation of PEVs in a power grid imposes many challenges on system planning and operations. This work aims to investigate optimal PEV coordination strategies with cost-benefit analysis. In Part I, we first present a new method to calculate the charging load of PEVs with a modified Latin hypercube sampling (LHS) method for handling the stochastic property of PEVs. We then propose a new two-stage optimization model to discover the optimal charging states of PEVs in a given day. Using this model, the peak load with charging load of PEVs is minimized in the first stage and the load fluctuation is minimized in the second-stage with peak load being fixed as the value obtained in the first stage. An algorithm based on linear mixed-integer programming is provided as a suitable solution method with fast computation. Finally, we present a new method to calculate the benefit and cost for a PEV charging and discharging coordination strategy from a social welfare approach. These methods are useful for developing PEV coordination strategies in power system planning and supporting PEV-related policy making.
Microglia, the only nonneuroepithelial cells found in the parenchyma of the CNS, originate during embryogenesis from the yolk sac and enter the CNS quite early (embryonic day 9.5-10 in mice). ...Thereafter, microglia are maintained independently of any input from the blood and, in particular, do not require hematopoietic stem cells as a source of replacement for senescent cells. Monocytes are hematopoietic cells, derived from bone marrow. The ontogeny of microglia and monocytes is important for understanding CNS pathologies. Microglial functions are distinct from those of blood-derived monocytes, which invade the CNS only under pathological conditions. Recent data reveal that microglia play an important role in managing neuronal cell death, neurogenesis, and synaptic interactions. In this article, we discuss the physiology of microglia and the functions of monocytes in CNS pathology. We address the roles of microglia and monocytes in neurodegenerative diseases as an example of CNS pathology.
Climate change and human activities have already caused degradation in a large fraction of vegetation on the Qinghai‐Tibetan Plateau (QTP). Many studies report that climate variability instead of ...overgrazing has been the primary cause for large‐scale vegetation cover changes on the QTP, for example, Lehnert et al., 2016, https://doi.org/10.1038/srep24367. However, it remains unclear how human activities (mainly livestock grazing) regulate vegetation dynamics under climate change. This paper takes the AVHRR/GIMMS Normalized Difference Vegetation Index (NDVI) as an indicator to analyze the growth status of vegetation zones in the QTP, which has highly sensitive to climate change. The spatiotemporal dynamics of vegetation growth between 1981 and 2015 were analyzed. The dual effects of climate change and human activities were examined by correlation analyses of data from 87 meteorological stations and economic statistical data of the QTP. Results show that: (a) The vegetation in central and southwestern QTP with high altitudes was improving due to the warm‐humid climate trend. An increase in temperature and a reduction in the harsh frigid climate at high altitudes due to global warming has resulted in expansions of the vegetated areas, with the NDVI showing a concordant increase. (b) The degraded areas were mainly confined to the northern and eastern QTP, which have high human and livestock population densities. In comparison to gently changing climate regimes, anthropogenic activities such as chronic concentration of population and livestock in the valleys with a less harsh climate exerts a much stronger pressure on vegetation. The study indicates that the anthropogenic pressures are much more intensive than the impact of climate change and are critical for the conservation and sustainable management of the QTP vegetation.
Plain Language Summary
Vegetation dynamics and its type are considered to be critical indicators of different climate regimes and have received significant attention from ecologists and climatologists. However, studies on the shift in vegetation toward higher altitudes and higher latitudes with climate warming from the vegetation zone redistribution perspective are relatively scarce. Our results suggest that the degraded areas of vegetation were mainly confined to the northern and eastern Qinghai‐Tibetan Plateau (QTP), which have high human and livestock population densities. In comparison to gently changing climate regimes, anthropogenic activities such as chronic concentration of population and livestock in the relatively less harsh valleys exerts a much stronger pressure on vegetation. Anthropogenic pressures were therefore found to be far more intensive than the impact of climate change and they were the big threats to the sustainability of the QTP.
Key Points
The vegetation with high altitudes was improving due to the warm‐humid climate trend
The degraded vegetation areas were mainly confined to high human and livestock population densities
Anthropogenic activities such as chronic concentration of population and livestock exerts a much stronger pressure on vegetation
Duchenne muscular dystrophy (DMD) is the most common genetic muscle disease affecting 1 in 3,500 live male births. It is an X-linked recessive disease caused by a defective dystrophin gene. The ...disease is characterized by progressive limb weakness, respiratory and cardiac failure, and premature death. Fibrosis is a prominent pathological feature of muscle biopsies from patients with DMD. It directly causes muscle dysfunction and contributes to the lethal DMD phenotype. Although gene therapy and cell therapy may ultimately provide a cure for DMD, currently the disease is devastating, with no effective therapies. Recent studies have demonstrated that ameliorating muscle fibrosis may represent a viable therapeutic approach for DMD. By reducing scar formation, antifibrotic therapies may not only improve muscle function but also enhance muscle regeneration and promote gene and stem cell engraftment. Antifibrotic therapy may serve as a necessary addition to gene and cell therapies to treat DMD in the future. Therefore, understanding cellular and molecular mechanisms underlying muscle fibrogenesis associated with dystrophin deficiency is key to the development of effective antifibrotic therapies for DMD.
The effect of the FEC additive on the cycling stability of the Sb-based anode for Na-ion batteries was investigated. The introduction of FEC in the electrolyte can improve the cycling stability of ...the Sb-based anode, due to a double-layer SEI film formed on the electrode surface.
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•Effect of FEC additive was investigated on the Sb-based anode for Na-ion batteries.•FEC additive can improve the cycling stability of the Sb-based anode.•A double-layer SEI film mechanism is suggested in the electrolyte with FEC.
The electrolyte additive has significant impact on the electrochemical performance of the alloy anode material for sodium-ion batteries. In this work, the surface structure, component and electrochemical performance of the SiC-Sb-C electrode in FEC-free and -containing electrolyte have been investigated by XPS, FTIR, EIS and electrochemical characterizations. The experimental results suggest that FEC actually participates in the formation process of the SEI films on the surface of the electrode. Based on the analysis of the experimental data, a double-layer SEI film mechanism should be suggested and can well explain the mutation of the resistant and potential observed in the charge/discharge curves and EIS. Therefore, the presence of FEC in the electrolyte can minimize the reductive decomposition of the electrolyte and change the morphology, structure and chemical component of the electrode, resulting in the improvement of the electrochemical performance of the electrode.
Continuing with a set of enabling techniques for the optimal coordination of plug-in electric vehicles (PEVs) in Part I, we present a case study in this paper using techniques based on the data ...collected in the Beijing-Tianjin-Tangshan Region (BTTR) China to discover optimal PEV coordination strategies and assess the attractiveness of these strategies. In Part II, we first present the charging characteristics for different categories of PEVs in BTTR and predict the optimal seasonal daily loads with PEVs under different PEV penetration levels using a two-stage optimization model in both 2020 and 2030. The simulation results indicate that optimal PEV coordination effectively reduces the peak load and smooths the load curve. Finally, we present a cost-benefit analysis of optimal coordination strategies by taking a social welfare approach. The analysis shows that the optimal coordination strategies are beneficial in terms of the reduction in capital investment in power grid expansion and that the attractiveness of a coordination strategy is related to the coordination level. The results also show that the fully coordinated charging and vehicle to grid are not the most attractive strategies. This case study is useful for better understanding the costs and benefits of PEV coordination strategies and for supporting PEV-related decision and policy making from a power system planning perspective.
A tin(ii) sulfide-carbon (SnS-C) nanocomposite is prepared by a simple high-energy mechanical milling method. XRD, SEM and TEM characterizations show that the nanocomposite is composed of well ...crystallized SnS nanoparticles with a size of about 15 nm, which are dispersed uniformly in the conductive carbon matrix. The SnS-C electrode exhibits a high Na storage capacity (568 mA h g super(-1) at 20 mA g super(-1)) and excellent cycling stability (97.8% capacity retention over 80 cycles) as well as high-rate capability. Ex situXRD result confirms a sequential conversion and alloying-dealloying reaction mechanism of the SnS-C electrode during the Na uptaking and extraction cycles. The superior electrochemical performance of the electrodes can be attributed to the small crystalline size of SnS and good carbon coating, which facilitate electrochemical utilization and maintain the structural integrity.
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