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A series of Mo-containing MFI zeolites with different Mo loadings (Mo-MFI-n, n represent the initial Si/Mo molar ratio) was hydrothermally synthesized by using tetrapropylammonium hydroxide as the template and Mo-EDTA complex as the Mo source. Various characterization results demonstrated that the use of the Mo-EDTA complex is beneficial for the incorporation of more Mo species into the MFI-type zeolites. The special complexing capability of EDTA2– plays a critical role in adjusting the release rate of the Mo species to combine with the Si tetrahedron species during the zeolite growth process, thus leading to a uniform distribution of Mo in the MFI framework. In addition, a small portion of extra-framework Mo clusters may be distributed inside the channels or near the pore window of the zeolites. The catalytic properties of these Mo-containing MFI zeolites were evaluated for the epoxidation of cyclohexene with H2O2 as the oxidant. The composition-optimized catalyst, Mo-MFI-50, efficiently converted cyclohexene to the corresponding epoxide with a relatively high conversion (93%) and epoxide selectivity (82%) at 75 °C after 9 h of reaction. Moreover, the resultant Mo-containing MFI catalyst exhibited excellent structural stability and recoverability and was easily recycled by simple filtration without the need for calcination treatment.

Although photocatalytic water splitting has excellent potential for converting solar energy into chemical energy, the challenging charge separation process and sluggish surface catalytic reactions significantly limit progress in solar energy conversion using semiconductor photocatalysts. Herein, we demonstrate a feasible strategy involving the surface assembly of cobalt oxide species (CoOx) on a visible-light-responsive Cd0.9Zn0.1S (CZS) photocatalyst to fabricate a hierarchical CZS@CoOx heterostructure. The unique hierarchical structure effectively accelerates the directional transfer of photogenerated charges, reducing charge recombination through the smooth interfacial heterojunction between CZS and CoOx, as evidenced by photoluminescence (PL) spectroscopy and various electrochemical characterizations. The surface cobalt species on the CZS material also act as efficient cocatalysts for photocatalytic hydrogen production, with activity even higher than that of noble metals. The well-defined CZS@CoOx heterostructure not only enhances the interfacial separation of photoinduced charges, but also improves surface catalytic reactions. This leads to superior photocatalytic performances, with an apparent quantum efficiency of 20% at 420 nm for visible-light-driven hydrogen generation, which is one of the highest quantum efficiencies measured among noble-metal-free photocatalysts. Our work presents a potential pathway for controlling complex charge separation and catalytic reaction processes in photocatalysis, guiding the practical development of artificial photocatalysts for successful transformation of solar to chemical energy.

Mammalian target of rapamycin (mTOR) is an evolutionary conserved kinase that senses the nutrient and energy status of cells, the availability of growth factors, stress stimuli and other cellular and environmental cues. It responds by regulating a range of cellular processes related to metabolism and growth in accordance with the available resources and intracellular needs. mTOR has distinct functions depending on its assembly in the structurally distinct multiprotein complexes mTORC1 or mTORC2. Active mTORC1 enhances processes including glycolysis, protein, lipid and nucleotide biosynthesis, and it inhibits autophagy. Reported functions for mTORC2 after growth factor stimulation are very diverse, are tissue and cell-type specific, and include insulin-stimulated glucose transport and enhanced glycogen synthesis. In accordance with its cellular functions, mTOR has been demonstrated to regulate cardiac growth in response to pressure overload and is also known to regulate cells of the immune system. The present manuscript presents recently obtained insights into mechanisms whereby mTOR may change anabolic, catabolic and stress response pathways in cardiomocytes and discusses how mTOR may affect inflammatory cells in the heart during hemodynamic stress. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Integration of Developmental and Environmental Cues in the Heart edited by Marcus Schaub and Hughes Abriel.

During stress conditions such as pressure overload and acute ischemia, the myocardial endothelium releases neuregulin-1β (NRG-1), which acts as a cardioprotective factor and supports recovery of the heart. Recently, we demonstrated that recombinant human (rh)NRG-1 enhances glucose uptake in neonatal rat ventricular myocytes via the ErbB2/ErbB4 heterodimer and PI3Kα. The present study aimed to further elucidate the mechanism whereby rhNRG-1 activates glucose uptake in comparison to the well-established insulin and to extend the findings to adult models. Combinations of rhNRG-1 with increasing doses of insulin did not yield any additive effect on glucose uptake measured as 3H-deoxy-d-glucose incorporation, indicating that the mechanisms of the two stimuli are similar. In c-Myc-GLUT4-mCherry-transfected neonatal rat cardiomyocytes, rhNRG-1 increased sarcolemmal GLUT4 by 16-fold, similar to insulin. In contrast to insulin, rhNRG-1 did not phosphorylate IRS-1 at Tyr612, indicating that IRS-1 is not implicated in the signal transmission. Treatment of neonatal rats with rhNRG-1 induced a signaling response comparable with that observed in vitro, including increased ErbB4-pTyr1284, Akt-pThr308 and Erk1/2-pThr202/Tyr204. In contrast, in adult cardiomyocytes rhNRG-1 only increased the phosphorylation of Erk1/2 without having any significant effect on Akt and AS160 phosphorylation and glucose uptake, suggesting that rhNRG-1 function in neonatal cardiomyocytes differs from that in adult cardiomyocytes. In conclusion, our results show that similar to insulin, rhNRG-1 can induce glucose uptake by activating the PI3Kα-Akt-AS160 pathway and GLUT4 translocation. Unlike insulin, the rhNRG-1-induced effect is not mediated by IRS proteins and is observed in neonatal, but not in adult rat cardiomyocytes.

Risk assessment of soil erosion addresses the likelihood of the occurrence of erosion as well as its consequences. This in turn can provide precautionary and relevant suggestions to assist with disaster reduction. In light of the great threat of soil erosion to global soil resources, it is necessary to implement this type of risk assessment. This study aims to appraise the risk of soil erosion caused by water along the Bohai Sea region during the rainy season. A new method, namely the RUSLE–IDM coupled model, which embeds the IDM (Information Diffusion Model) into the RUSLE(Revised Universal Soil Loss Equation)model, is applied to reveal soil erosion risk in different scenarios, with rainfall exceeding the probability of 0.1 and 0.02 respectively. From this case study, three conclusions can be drawn as follows: (i) This coupled method can effectively examine soil erosion risk and show comparable results of different scenarios, which cannot only calculate the erosion amount, but also identify the likelihood; (ii) Soil erosion caused by water is serious from July to September, but comparatively speaking, the greatest amount of attention should be paid to the prevention of soil erosion in July, as the erosion amount at this time is times larger than during September; (iii) Vegetation coverage and soil erosion control practices are controllable and important factors for the future soil conservation in this area.

Research on changes of land use in natural reserves is a critical issue and discussion of land use policies relevant to them is needed for their preservation in face of pressures of local socio-economic development. This study examined Tianjin Palaeocoast and Wetland National Natural Reserve (TJPW) and reviewed its development processes, status of adjustments and evolutionary mechanisms. Land use/cover change (LUCC), driving forces, adjustment schemes, and land use policy changes were also investigated. Land use changes were studied by supervised classification of Landsat TM remote sensing images of 1988, 1998, and 2008, respectively. Local economic development is the main driving force of LUCC. As such, it is critical to lay out a scientific, integrated development plan for adjustment that pays more attention to changes in natural reserve land properties and establishes ecological protection networks. In addition, the ecological integrity of natural reserves needs to be preserved and sustained instead of randomly modifying their boundaries to meet the demand of key infrastructure projects. Therefore, the results described in the study provides a detailed reference model that can lead to adopt boundary adjustment strategy to balance coastal wetland protection and a sustainable development of resource’s management.

In the last decade, 1D semiconductor nanostructures attracted much attention due to their potential applications in electronics, optoelectronics, sensor, and biotechnology. Among various synthetic strategies, the electrochemical method is a relatively simple and effective way to prepare 1D semiconductor nanostructures. Moreover, electrochemical methods can afford precise processes for controlling the compositions and morphologies of the nanostructured materials. In this review, we present a systematic description of the electrochemical synthesis of oriented and hierarchical quasi-1D semiconducting nanostructures. The main contents containing: (1) electrodeposition of materials in hard porous membranes templates with 1D pore geometry or under assistance of the capping reagents for oriented nanowires/nanorods film; (2) multi-step template replication methods, two-step synthetic strategy and anodization methods for uniform nanotube arrays; (3) electrochemical synthetic strategies for complex hierarchical nanostructured films. Additionally, we give a brief introduction about the applications of these quasi-1D semiconducting nanostructures.

As a continuation of our efforts to discover and develop the apoptosis inducing 4-aryl-4H-chromenes as novel anticancer agents, we explored the SAR of 4-aryl-4H-chromenes with modifications at the 7- and 5-, 6-, 8-positions. It was found that a small hydrophobic group, such as NMe2, NH2, NHEt, and OMe, is preferred at the 7-position. Di-substitution at either the 5,7-positions or the 6,7-positions generally led to a large decrease in potency. Di-substitution at the 7,8-positions, in general, was found to result in potent compounds. 7-NMe2, 7-NHEt, 7-OMe, and 7,8-di-NH2 analogs were found to have similar SAR for the 4-aryl group, and several 7-substituted and 7,8-di-substituted analogs were found to have similar potencies as the lead compound MX58151 (2a) both as caspase activators and inhibitors of cell proliferation.