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Proper interface and band alignment always play essential roles in the separation of photoexcited charge of photocatalysts. In this work, we prepared a homodispersed S-scheme carbon nitride homojunction with local electron structure difference by a facile pre-doping and two-step calcination approach. Boron doping into heptazine created extra acceptor impurity, and phosphorus doping into heptazine created extra donor impurity, which eventually modulated the electronic structure of carbon nitride. As heptazines with different element doping were integrated into carbon nitride by recalcination, B–CN and P–CN formed a homodispersed homojunction and thus produced a rich interface. Meanwhile, caused by Fermi energy levels equilibrium, the band bending constructed an S-scheme homojunction, which stimulated photogenerated electrons to transfer from CB of B–CN to VB of P–CN. The homodispersed S-scheme homojunction structure led to efficient suppression of recombination of photoinduced charge and retained stronger redox charge. Consequently, the photocatalytic performance was dramatically boosted to 2620 μmol g−1from 60 μmol g−1of pure CN in 4-h hydrogen evolution from water. This novel method for electron structure engineering helped to provide a new strategy for designing homojunction photocatalysts with excellent photocatalytic performance.

Nitrogen-doped microporous carbon using carboxylic acid-functionalized imidazole-type polymers (PDVA) as a carbon precursor was fabricated by a one-step carbonization method without an additional activator. The introduction of acrylic acid was beneficial to promote the formation of microporous structures during the pyrolysis process. By changing the carbonization temperature, the textural properties and surface nitrogen content of the carbon materials were tuned. The synergistic effect of the microporous structure and basic nitrogen sites was conducive to enhancing the CO2adsorption performance of porous carbon materials. The CO2adsorption quantity of PDVA-C-800 obtained without an additional activator reached 3.18 mmol·g–1under 1 bar at 25 °C, which was comparable to that of the reported carbon materials. Besides, PDVA-C-800 possessed excellent cycle stability and recyclability. The fabrication of microporous nitrogen-doped carbon derived from carboxylic acid-functionalized imidazole-type polymers provided an original idea for CO2uptake.

Porous g-C 3 N 4 nanosheets (PCN) were prepared by the nickel-assisted one-step thermal polymerization method. Hydrogen (H 2) which was produced by the reaction between nickel (Ni) foam and ammonia (NH 3) defined the structure and properties of PCN. During the formation of PCN, the participation of H 2 not only enhanced the spacing between layers but also boosted the specific surface area that more active sites were exposed. Additionally, H 2 promoted pores formation in the nanosheets, which was beneficial to the transfer of photons through lamellar structure and improved the absorption efficiency of visible light. Remarkably, the obtained PCN possessed better Cr(VI) photocatalytic reduction efficiency than pure g-C 3 N 4. The reaction rate constant (k) of PCN (0.013 min−1) was approximately twice that of bare g-C 3 N 4 (0.007 min−1). Furthermore, the effects of original pH and concentration of Cr(VI)-containing solution on removal efficiency of Cr(VI) were explored. A possible photocatalytic mechanism was proposed based on the experiments of radical scavengers and photoelectrochemical characterizations. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the role of thioredoxin 2 (Trx2) inhibition induced by intracellular methylglyoxal (MGO) in pancreatic beta-cell mitochondrial dysfunction and apoptosis. Methods: Rat pancreatic beta-cell line INS-1 cells were treated with Glo1 siRNAs or exogenous MGO to increase intracellular MGO. AGEs formation was detected by ELISA and mitochondrial ROS was detected by probe MitoSOX. Transmission electron microscopy (TEM) analysis and ATP content were measured to evaluate mitochondrial function. Trx2 expression was manipulated by overexpression with recombinant Trx2 lentivirus or knockdown with Trx2 siRNAs, and effects on apoptosis and insulin secretion were measured by flow cytometry and ELISA, respectively. Results: The increase of intracellular MGO by Glo1 blockage or MGO treatment led to advanced glycation end products (AGEs) overproduction, mitochondrial ROS increase, and insulin secretion paralysis. These were probably due to MGO-induced inhibition of mitochondrial Trx2. Trx2 inhibition by blockage of either Glo1 or Trx2 impaired mitochondrial integrity, inhibited cytochrome C oxidases subunit 1 and 4 (Cox1 and Cox4) expression and further reduced ATP generation, and all of these might lead to insulin paralysis; whereas Trx2 overexpression partially reversed MGO-induced oxidative stress, attenuated insulin secretion by preventing mitochondrial damage. Trx2 overexpression also retarded MGO-induced apoptosis of INS-1 cell through inhibiting ASK1 activation and downregulation of the ASK1-p38 MAPK pathway. Conclusions: Our results reveal a possible mechanism for beta-cell oxidative damage upon intracellular MGO-induced Trx2 inactivation and mitochondrial dysfunction and apoptosis.

Waste plastics offer valuable feedstock for refining facilities. Their well-structured molecular compositions and functional groups make them ideal candidates for conversion into high-value chemicals and fuels, playing a pivotal role in carbon recycling. Achieving this transformation demands not only the precise design of deconstruction reaction systems but also the overcoming of technological barriers, necessitating a collaborative partnership between fundamental research and industrial expertise. In this context, we present a roadmap for advancing the recycling and upcycling of plastic waste, commencing a thorough assessment of technological challenges across the entire plastics recycling chain.

SID1 transmembrane family member 2 (Sidt2) is an integral lysosomal membrane protein. To investigate its explicit function, we generated a global Sidt2knockout mouse model (Sidt2−/−). Compared with the littermate controls, Sidt2−/−mice exhibited a remarkable accumulation of lipid droplets in liver. First, it was observed that food consumption, hepatocyte fatty acid uptake and de novo lipogenesis, hepatocyte lipolysis, and TG secretion in the form of very low density lipoprotein were comparable between Sidt2−/−and WT mice. However, the hepatic β-oxidation of fatty acids decreased significantly as revealed by a low level of serum β-hydroxybutyrate in the Sidt2−/−mice along with normal mRNA expression of genes involved in fatty acid oxidation. In addition, the classical autophagy pathway marker proteins, p62 and LC3-II, increased in liver, along with compromised autophagic flux in primary hepatocytes, indicating a block of autophagosome maturation due to Sidt2 deficiency, which was also supported by electron microscopy image analysis both in livers and in primary hepatocytes from Sidt2−/−mice. It was concluded that Sidt2 plays an important role in mouse hepatic lipid homeostasis by regulating autophagy at the terminal stage.

In this study, the adsorption capacities of powdered activated carbon (PAC) and activated coke (AC) for organic components with different characteristics from the secondary effluents of urban waste water plant were examined, and their adsorption mechanisms were discussed. The results showed that Freundlich isothermal model and pseudo-second-order model could describe the processes of PAC and AC to effluent organic matter (EfOM) from urban wastewater plant effectively. Soluble microbial metabolites and humus were the major components of organics in the secondary effluents, and most of them were with small molecular weight which is less than 3 kDa (the proportion is 28.3%). PAC effectively adsorbed the organics with small molecular weight (less than 3 kDa) and the removal rate of dissolved organic carbon (DOC) was 67.2%, whereas AC effectively adsorbed the organics with molecular weight of 3 kDa–10 kDa and the DOC removal rate was 45.5%. Compared with AC, PAC has characteristics of smaller particle size, larger specific surface area, rougher surface and lower Zeta potential, which leads to more effective adsorption sites and better results. AC can effectively adsorb the organics with variable molecular weight in water and can be used as replacement of PAC in the advanced purification of reclaimed water.

Photocatalytic CO2reduction with H2O into hydrocarbon fuels represented an appealing approach to mitigate the energy crisis and greenhouse effect. However, isolated BiOBr (BOB) usually possessed rapid recombination of photogenerated carriers and low solar energy utilization, which restricted the elevation of photocatalytic performance. Herein, a direct Z-scheme porous N-rich g-C3N5/BiOBr (pCN/BOB) photocatalyst was fabricated through in situ hydrothermal approach. Furthermore, benefiting from Z-scheme heterojunction and tight surface contact, the pCN/BOB exhibited remarkably enhanced photoreduction ability of CO2under visible light. Specially, 10% pCN/BOB exhibited the optimized photocatalytic performance for CH3OH production (3.08 μmol·g−1·h−1), approximately four times that of isolated BOB, whose improved photocatalytic performance was ascribed to the separation of photoinduced carriers by Z-scheme heterojunction and intimate interface contact. Meanwhile, the photogenerated charge transfer mechanism was calculated by work function calculation. Moreover, pCN/BOB exhibited good reusability for photocatalytic CO2reduction. This work provided an efficient strategy for designing and preparing the high-efficiency photocatalysts for converting solar energy.

Lysosomal storage disorders (LSDs) are a group of >50 different types of inherited metabolic disorders that result from defects in the lysosome. The aim of this study was to investigate the distribution and demographic characteristics of the different subtypes of LSDs in Eastern China. From 2006 to 2012, 376 out of 1331 clinically suspected patients were diagnosed with 17 different subtypes of LSDs at our hospital. Mucopolysaccharidoses (MPS) were the most common group of LSDs (50.5%), followed by sphingolipidoses (25.4%) and Pompe disease (19.8%). Mucolipidosis type II/III accounted for the remaining 4% of diagnosed LSDs. MPS II was the most common form of MPS, comprising 47.4% of all MPS cases diagnosed, followed by MPS IVA (26.8%) and MPS I (16.3%). Gaucher disease and Niemann–Pick disease type A/B were the two most common forms of sphingolipidoses. There was a large variation in the time between disease onset and eventual diagnosis, from 0.3 years in infantile-onset Pompe disease to 30 years in Fabry disease, highlighting timely and accurate diagnosis of LSDs as the main challenge in China.

Nitrogen and oxygen-codoped microporous carbon was prepared using carboxylic acid polymer (PDVH) with urea as precursor. Due to the acid-base interaction, urea was trapped on the surface of the precursor, enhancing of the specific surface area, the nitrogen content and pore volume of the porous carbon after carbonization. Among these materials, the PDVH-NC-2.0 obtained an uptake of CO2to 3.05 mmol g-1at 25 ℃ and 1 atm. Meanwhile, the CO2adsorption selectivity of these PDVH-NC-X ranged from 21.3 to 30.4 (CO2/N2=85:15) based on the IAST adsorbed solution theory, resulting from the increased amount of the pyrrolic-N and oxidized-N, which enhanced the adsorption selectivity of CO2. Furthermore, the weak interaction involving N sites with CO2should be responsible for the improvement of the uptake of CO2through electrostatic potential mapping (ESP) and interaction region indicator (IRI). Finally, the CO2uptake of the PDVH-NC-2.0 was still maintained after five cycles of reuse, which meant this porous carbon would be superior alternative for CO2capture.