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As one of the most induced genes in activated macrophages, immune-responsive gene 1 (IRG1) encodes a mitochondrial metabolic enzyme catalysing the production of itaconic acid (ITA). Although ITA has an anti-inflammatory property, the underlying mechanisms are not fully understood. Here we show that ITA is a potent inhibitor of the TET-family DNA dioxygenases. ITA binds to the same site on TET2 as the co-substrate α-ketoglutarate, inhibiting TET2 catalytic activity. Lipopolysaccharide treatment, which induces Irg1 expression and ITA accumulation, inhibits Tet activity in macrophages. Transcriptome analysis reveals that TET2 is a major target of ITA in suppressing lipopolysaccharide-induced genes, including those regulated by the NF-κB and STAT signalling pathways. In vivo, ITA decreases the levels of 5-hydroxymethylcytosine, reduces lipopolysaccharide-induced acute pulmonary oedema as well as lung and liver injury, and protects mice against lethal endotoxaemia, depending on the catalytic activity of Tet2. Our study thus identifies ITA as an immune modulatory metabolite that selectively inhibits TET enzymes to dampen the inflammatory responses.

Sirtuin 5 (SIRT5) is a member of the NAD+-dependent sirtuin family of protein deacylase that catalyzes removal of post-translational modifications, such as succinylation, malonylation, and glutarylation on lysine residues. In light of the SIRT5's roles in regulating mitochondrion function, we show here that SIRT5 deficiency leads to suppression of mitochondrial NADH oxidation and inhibition of ATP synthase activity. As a result, SIRT5 deficiency decreases mitochondrial ATP production, increases AMP/ATP ratio, and subsequently activates AMP-activated protein kinase (AMPK) in cultured cells and mouse hearts under energy stress conditions. Moreover, Sirt5 knockout attenuates transverse aortic constriction (TAC)-induced cardiac hypertrophy and cardiac dysfunction in mice, which is associated with decreased ATP level, increased AMP/ATP ratio and enhanced AMPK activation. Our study thus uncovers an important role of SIRT5 in regulating cellular energy metabolism and AMPK activation in response to energy stress.

As a representative technique in electronics, the Smith Chart provides a fast, less‐computation, and graphical approach to solve the problems related to impedance matching. In this paper, we transplanted the Smith Chart into the design and analysis of a microwave metamaterial absorber (meta‐absorber) to develop an analytical and graphical approach for impedance matching of electromagnetic wave absorption. Before the structural design, four traces on the Smith Chart plane from the load to arrive at the impedance matching point (the center of the Smith Chart) can be graphically found to obtain perfect absorption. Then, we have designed four impedance matching circuit networks made of resistance, inductance, and capacitive elements and transmission lines to fit the four traces. Then, the matching circuits are mapped into the meta‐absorber structure by using three types of proposed layers. The full simulation method based on the finite element method is used to verify the proposed concept. Furthermore, an external dielectric loading strategy has been developed to achieve good angular stability up to 60° for the radar cross section reduction under transverse electric and transverse mangetic polarization incidence. The proposed method may provide a convenient way for various microwave devices, such as antennas. [ABSTRACT FROM AUTHOR]

The foundation for accurately understanding regional land-use structures and pursuing the coordination of human–land relations is the scientific identification and simulation of temporal and spatial evolution patterns of land-use spatial conflict (LUSC). Based on the production–living–ecological space (PLES) perspective, a land-use spatial conflict identification and intensity diagnosis model (LUCSII) was constructed using a landscape ecology index. The methods of geographic information system (GIS), spatial autocorrelation analysis, and mathematical statistics were used to achieve the spatial pattern of LUSC over the last 20 years, and the GMOP–Markov–PLUS model was used to simulate the evolution of LUSC in the future under various scenarios. The results indicated that our established LUCSII could accurately identify potential land-use spatial conflict areas in geoparks. The GMOP–Markov–PLUS model constructed had also scientifically predicted the future land-use patterns under different scenarios, successfully demonstrating the changing process of spatial conflict pattern evolution. The research proposed three different plans for the long-term land use of YG, including ecological protection, economic development, and long-term development perspectives. Finally, the research further emphasized the importance for sustainable development of geoparks. More attention should be paid to the optimal allocation of land-use structure and the coordinated development of human–land relationships. [ABSTRACT FROM AUTHOR]

In recent years, the evaluation of carbon sources and carbon sinks has become one of the major research topics. The temporal and spatial distribution of carbon flux and some factors that affect carbon flux were analyzed in this paper based on the Net Ecosystem Exchange (NEE) data, which were provided by Greenhouse Gases Observing Satellite (GOSAT) project and FLUXNET project. Then, we found that carbon flux had obvious seasonal variation. It was carbon sink in summer and carbon source in winter. The total amount of carbon flux in July or August was about -1.377 ~ -1.882 gcm-2day-1, and 0.64 gcm-2day-1 in November. The fluctuation of carbon flux in coastal area was stronger than that in inland. Forest areas had stronger carbon storage capacity than that in other vegetation areas, and the flux in forest areas had the largest change. The vegetation coverage was larger, and the carbon storage capacity was stronger.