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A simple citric acid (CA)‐ammonium molybdate co‐impregnation method was applied to prepare the Mo‐based MCM‐49 catalyst to ameliorate the dispersion of metallic Mo for methane dehydro‐aromatization reaction (MDA). The newly prepared catalyst has higher crystallinity and maintains the original morphology of zeolite, which proves that the addition of citric acid will not destroy the basic structure of the catalyst. Based on H2‐TPR, UV‐vis, NH3‐TPD and XPS characterization results, it can be corroborated that the introduction of citric acid changes the coordination state of Mo element. Brønsted acid sites can stabilize the monomeric Mo oxide species by increasing MoOx migration into the MCM‐49 zeolite pores channel after calcination, which may affect the distribution of active sites MoCx and thus improve MDA catalytic activity. The experimental results show that the Mo‐based MCM‐49 catalyst with nCA : nMo ratios of 1.0 has higher methane conversion (14.5 %) and aromatics yield (9.8 %). The combination of XPS, TG and Raman tests of the spent catalyst confirms that the newly synthesized catalysts produce less carbon deposition, thus improving the catalytic durability during the MDA reaction. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC) is the second most lethal cancer worldwide. Glutamine is an essential, extracellular nutrient which supports HCC growth. Dietary glutamine deficiency may be a potential therapeutic approach for HCC. HCC cells overcome metabolic challenges by rewiring their metabolic pathways for rapid adaptations. The efficiency of dietary glutamine deficiency as HCC treatment is examined and the adaptation machinery under glutamine depletion in HCC cells is unraveled. Using genome‐wide CRISPR/Cas9 knockout library screening, this study identifies that pyruvate dehydrogenase α (PDHA), pyruvate dehydrogenase β (PDHB), and pyruvate carboxylase (PC) in pyruvate metabolism are crucial to the adaptation of glutamine depletion in HCC cells. Knockout of either PDHA, PDHB or PC induced metabolic reprogramming of the tricarboxylic acid (TCA) cycle, disrupts mitochondrial function, leading to the suppression of HCC cell proliferation under glutamine depletion. Surprisingly, dietary glutamine restriction improves therapeutic responses of HCC to PDH or PC inhibitor in mouse HCC models. Stable isotope carbon tracing confirms that PDH or PC inhibitors further disrupt the metabolic rewiring of the TCA cycle induced by dietary glutamine depletion in HCC. In summary, the results demonstrate that pyruvate metabolism acts as novel targetable metabolic vulnerabilities for HCC treatment in combination with a glutamine‐deficient diet. [ABSTRACT FROM AUTHOR]

More than 90% of excess energy trapped by greenhouse gases is accumulated in the oceans. Ocean heat content (OHC) and its changes are therefore fundamental metrics to monitor climate change. However, due to sparse observation sampling before the 1950s, accurate observation‐based estimations only exist for the second half of the 20th century. A 16‐member ensemble of historical ocean reanalyses is used for the first time to compile a unique estimate of 20th century oceanic warming rates. The reanalyses combine dynamical ocean general circulation models with historical observations and observation‐based atmospheric forcing. Ocean heat content tendencies (OHCT) from the multireanalysis ensemble (MRE) agree well with independent estimates of ocean heat content, and show a coherent evolution with records of Earth's energy imbalance from atmospheric reanalyses and atmospheric CO2 concentration at a range of timescales. OHCT from reanalyses proves to be a more effective climate change proxy, that is, more closely related to independent climate indexes, than observed surface warming tendencies that contain high‐frequency variability not related to the climate change signature, or historical coupled model simulations, which neglect interannual fluctuations. The ensemble mean estimate of the century‐long ocean warming rate is 0.26 ± 0.08 W m−2. The warming rate of 0.84 ± 0.21 W m−2 estimated from 1993 onwards is unprecedented. The global decadal warming rate is persistently positive from about 1925 onwards, except for two neutral periods. The Indian Ocean exhibits the highest relative contribution to centennial heat accumulation, while the Atlantic Ocean plays an increasingly prominent role, especially during the 1995–2004 decade. These findings are in agreement with previous studies. [ABSTRACT FROM AUTHOR]

Alkali soil is a major abiotic constraint that limits plant distribution and yield in the northeast of China. Puccinellia tenuiflora is considered the most promising grass species for salt‐alkali grassland restoration. However, there is little information on the molecular mechanisms underlying how arbuscular mycorrhizal fungi (AMF) enhances P. tenuiflora stress responses in alkali‐degraded soil. In this study, AMF colonization, growth, photosynthetic pigments, and inorganic ion contents were measured. Isobaric tags for relative and absolute quantification‐based quantitative proteomic technology were employed to identify the differentially abundant proteins in P. tenuiflora seedlings with or without AMF under alkalinity stress. The results showed that AMF colonization increased seedling biomass, photosynthetic pigment contents, and K+/Na+ ratio under alkalinity stress. Moreover, a total of 598 proteins were significantly differentially regulated in P. tenuiflora seedlings after AMF inoculation under alkalinity stress compared with under alkalinity stress alone. The results showed that AMF inoculation significantly improved protein synthesis, reactive oxygen species scavenging, and nitrogen metabolism to promote the biosynthesis of osmotic substances in response to alkalinity stress. In addition, P. tenuiflora seedlings produced more energy to compensate for the energy loss caused by alkalinity stress after AMF inoculation. In conclusion, these findings provide new insights into the physiological mechanisms of the response to alkali‐degraded soil in P. tenuiflora seedlings with AMF and also clarify the role of AMF in the molecular regulation network of P. tenuiflora under alkalinity stress. [ABSTRACT FROM AUTHOR]

The Earth's energy imbalance (EEI) is stored in the oceans for the most part. Thus, estimates of its variability can be ingested in ocean retrospective analyses to constrain the global ocean heat budget. Here we propose a scheme to assimilate top of the atmosphere global radiation imbalance estimates from Clouds and the Earth's Radiant Energy System (CERES) in a coarse-resolution variational ocean reanalysis system (2000-2014). The methodology proves able to shape the heat content tendencies according to the EEI estimates, without compromising the reanalysis accuracy. Spurious variability and underestimation (overestimation) present in experiments with in situ (no) data assimilation disappear when EEI data are assimilated. The warming hiatus present without the assimilation of EEI data is mitigated, inducing ocean warming at depths below 1,500 m and slightly larger in the Southern Hemisphere, in accordance with recent studies. Furthermore, the methodology may be applied to Earth System reanalyses and climate simulations to realistically constrain the global energy budget. [ABSTRACT FROM AUTHOR]

Two historical ocean reanalyses that cover the period from 1900 to 2010 are performed. One ocean reanalysis (CHOR_AS) assimilates both sea-surface temperature (SST) and vertical profile data with a 3D-Var assimilation scheme, while the other one (CHOR_RL) assimilates vertical profile data, but is nudged to monthly Hadley Centre global sea Ice coverage and SST (HadISST) reconstructed fields. The reanalyses are thus designed to investigate the impact of different strategies for constraining the SST in long-term assimilation experiments and the feasibility of assimilating subsurface observations in the same kind of experiments. The atmospheric forcing comes from the ensemble mean of the Twentieth-Century Reanalysis version 2 (20CRv2). Due to biases being particularly large at high latitudes, corrections are applied to the atmospheric forcing, based on the comparison with ECMWF's ERA-Interim during the overlapped period. In general, these ocean reanalyses capture trends and variability of key ocean parameters. A warm bias of SST in CHOR_AS in the first half of the century leads to incorrect long-term trends. However, SST anomalies in both CHOR_AS and CHOR_RL are realistically captured. Heat contents at 0-300, 0-700 and 0-2000 m have an increasing trend in both CHOR_RL and CHOR_AS, consistent with available datasets for the second half of the century. In order to reproduce realistic mass transport, mixed-layer depth and eddy kinetic energy, it is necessary to assimilate vertical profile data, although this leads to some discontinuities in the reanalysis time series. Based on these findings, we suggest ideas for the requirements of future historical ocean reanalyses, such as related to the necessity of applying bias correction and minimizing the effects of the observing network discontinuities. Meanwhile, the comparison between CHOR_RL and CHOR_AS shows that both direct assimilation and the nudging scheme have their advantages and disadvantages. A combination of these two schemes is desirable in future work. [ABSTRACT FROM AUTHOR]