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The temperature sensitivity (Q10) of soil organic C (SOC) decomposition is an important parameter to predict C dynamics under climate change. Given that SOC is mainly protected by aggregates and minerals, differentiating the Q10 of the two C fractions helps to explain bulk soil C dynamics. In the present study, we collected agricultural soils from adjacent paddy and upland areas in mid‐temperate (Mollisols) and subtropic (Ultisols) regions of China. We employed density fractionation to separate aggregate‐protected and free mineral‐associated C fractions of soil samples and determined the Q10 of SOC and the two C fractions at 15 and 25°C incubated conditions. Results showed that the Q10 of SOC for Mollisols were lower than that for Ultisols, with an exception of aggregates in upland soils. Aggregate‐protected C had lower Q10 than free mineral‐associated C, except in the upland Mollisols. The Q10 of SOC was negatively correlated with the proportion of C protected in aggregates, whereas it was positively correlated with the proportions of mass or C of free minerals. Given that the mass and C proportion of aggregates in bulk soils of Mollisols were 271% and 80% higher than of Ultisols, respectively, the SOC of Mollisols exhibited lower Q10 than Ultisols. Therefore, stronger soil aggregation and higher proportion of aggregate‐protected C contributed to the lower temperature sensitivity of SOC in Mollisols. Consequently, agricultural practices aimed at promoting soil aggregation will alleviate SOC loss under future global warming scenarios. [ABSTRACT FROM AUTHOR]

In this work, a novel electrocatalyst, Mn0.3Ce0.7O2, with relatively high power performance has been, for the first time, proposed for metal/air batteries. The as-prepared samples are well characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), inductively coupled plasma (ICP) and nitrogen sorption experiments. Meanwhile, electrocatalytic activity towards the reduction of oxygen of Mn0.3Ce0.7O2 is compared with those of the pure MnO2 and CeO2. It is observed that the Mn0.3Ce0.7O2 solid solution is well formed after the calcination. Electrochemical results show that Mn0.3Ce0.7O2 exhibits much higher electrocatalytic activity in the oxygen reduction reaction (ORR) than pure MnO2 under high discharge current density, which is probably attributed to the effective activation of molecular oxygen over the Mn0.3Ce0.7O2 solid solution and higher surface area. [ABSTRACT FROM AUTHOR]

The transcription factor for immunoglobulin heavy-chain enhancer 3 (TFE3) is a member of the microphthalmia (MiT/TFE) transcription factor family. Dysregulation of TFE3 due to chromosomal abnormalities is associated with a subset of human renal cell carcinoma. Little structural information of this key transcription factor has been reported. In this study, we determined the crystal structure of the helix-loop-helix leucine zipper (HLH-Lz) domain of human TFE3 to a resolution of 2.6 Å. The HLH-Lz domain is critical for the dimerization and function of TFE3. Our structure showed that the conserved HLH region formed a four-helix bundle structure with a predominantly hydrophobic core, and the leucine zipper region contributed to the function of TFE3 by promoting dimer interaction and providing partner selectivity. Together, our results elucidated the dimerization mechanism of this important transcription factor, providing the structural basis for the development of inhibiting strategies for treating TFE3 dysregulated diseases. • TFE3 is a key transcription factor associated with a subset of human kidney cancer. • The crystal structure of the HLH-Lz domain of human TFE3 is determined. • The dimerization mechanism within HLH-Lz domain is analyzed. • We propose a possible strategy for inhibiting TFE3 activity. [ABSTRACT FROM AUTHOR]

Efficient utilization of organic materials based on the rich resources in the karst region can promote soil fertility. Microorganisms have a crucial influence on soil phosphorus availability. phoD is considered to be the encoding phosphatase gene that can reflect the hydrolysis of organophosphorus compounds for the soil bacterial community. Molecular analysis of the phoD -harboring bacterial gene provides insight into promoting soil phosphorus availability under different fertilization managements. However, the effects of organic materials on soil phosphorus fractions associated with phoD -harboring bacterial communities are poorly understood. This study comprehensively investigated the effects of organic materials on soil phosphorus availability and explored environmental drivers of phoD -harboring bacteria in the Karst region. Here, six treatments were designed in the field as follows:non-fertilized control (CK), inorganic fertilization (NPK), inorganic fertilization combined with straw (NPKS), inorganic fertilization combined with manure (NPKM), inorganic fertilization combined with sludge (NPKL), and inorganic fertilization combined with sugarcane ash (NPKA). The phoD -harboring bacterial community in Karst region soil was analyzed using high-throughput sequencing. The results showed that the content of total P (TP), Olsen-P, and Ca 2 -P increased with the years after organic material application, whereas the content of CaCl 2 -P first decreased and then increased. Compared to that under the CK treatment, organic material application, especially NPKL treatment, significantly increased soil total nitrogen (TN), TP, Olsen-P, CaCl 2 -P, and Ca 2 -P contents, followed by those in the NPKA and NPKM treatments. Correlation analysis showed that the contents of CaCl 2 -P, Ca 2 -P, and Olsen-P were significantly positively correlated with soil exchangeable calcium (Ca-ex) content. Redundancy analysis (RDA) showed that TN, Ca-ex, soil organic carbon (SOC), and total potassium (TK) contents were the key factors affecting soil P fractions. Using high-throughput sequencing, we found that only NPKS increased the richness of phoD -harboring bacteria compared to that under the control treatment. No significant difference was observed in the phoD -harboring bacterial community among all treatments. The RDA model selected the Ca-ex, TK, Olsen-P, pH, and SOC as the key environmental predictors for the phoD -harboring bacterial community. In summary, soil phosphorus availability can be improved through the input of organic materials and inorganic fertilizer combined with manure, sludge, and ash. These additions were suitable for nutrient management and sustainable development in farmland soil in the Karst region of Guangxi.