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Dysregulation of alternative splicing is implicated in many human diseases, and understanding the genetic variation underlying transcript splicing is essential to dissect the molecular mechanisms of cancers. We aimed to provide a comprehensive functional dissection of splicing quantitative trait loci (sQTLs) in cancer and focus on elucidating its distinct role in colorectal cancer (CRC) mechanisms. We performed a comprehensive sQTL analysis to identify genetic variants that control messenger RNA splicing across 33 cancer types from The Cancer Genome Atlas and independently validated in our 154 CRC tissues. Then, large-scale, multicenter, multi-ethnic case-control studies (34,585 cases and 76,023 controls) were conducted to examine the association of these sQTLs with CRC risk. A series of biological experiments in vitro and in vivo were performed to investigate the potential mechanisms of the candidate sQTLs and target genes. The molecular characterization of sQTL revealed its distinct role in cancer susceptibility. Tumor-specific sQTL further showed better response to cancer development. In addition, functionally informed polygenic risk score highlighted the potentiality of sQTLs in the CRC prediction. Complemented by large-scale population studies, we identified that the risk allele (T) of a multi-ancestry–associated sQTL rs61746794 significantly increased the risk of CRC in Chinese (odds ratio, 1.20; 95% CI, 1.12–1.29; P = 8.82 × 10–7) and European (odds ratio, 1.11; 95% CI, 1.07–1.16; P = 1.13 × 10–7) populations. rs61746794-T facilitated PRMT7 exon 16 splicing mediated by the RNA-binding protein PRPF8, thus increasing the level of canonical PRMT7 isoform (PRMT7 -V2). Overexpression of PRMT7 -V2 significantly enhanced the growth of CRC cells and xenograft tumors compared with PRMT7 -V1. Mechanistically, PRMT7-V2 functions as an epigenetic writer that catalyzes the arginine methylation of H4R3 and H3R2, subsequently regulating diverse biological processes, including YAP, AKT, and KRAS pathway. A selective PRMT7 inhibitor, SGC3027, exhibited antitumor effects on human CRC cells. Our study provides an informative sQTLs resource and insights into the regulatory mechanisms linking splicing variants to cancer risk and serving as biomarkers and therapeutic targets. [Display omitted] The comprehensive splicing quantitative trait loci resource highlighted the distinct power of splicing quantitative trait loci signals to uncover the molecular mechanisms of cancer and demonstrated that splicing quantitative trait loci rs61746794 contributed to increased risk of colorectal cancer by promoting the splicing of PRMT7 exon 16, presenting a novel lead for a biologically interpretable paradigm for cancer risk. [ABSTRACT FROM AUTHOR]

Epidemiological studies show an association between low body selenium and the risk of hypertension. However, whether selenium deficiency causes hypertension remains unknown. Here, we report that Sprague-Dawley rats fed a selenium-deficient diet for 16 weeks developed hypertension, accompanied with decreased sodium excretion. The hypertension of selenium-deficient rats was associated with increased renal angiotensin II type 1 receptor (AT 1 R) expression and function that was reflected by the increase in sodium excretion after the intrarenal infusion of the AT 1 R antagonist candesartan. Selenium-deficient rats had increased systemic and renal oxidative stress; treatment with the antioxidant tempol for 4 weeks decreased the elevated blood pressure, increased sodium excretion, and normalized renal AT 1 R expression. Among the altered selenoproteins in selenium-deficient rats, the decrease in renal glutathione peroxidase 1 (GPx1) expression was most prominent. GPx1, via regulation of NF-κB p65 expression and activity, was involved in the regulation of renal AT 1 R expression because treatment with dithiocarbamate (PDTC), an NF-κB inhibitor, reversed the up-regulation of AT 1 R expression in selenium-deficient renal proximal tubule (RPT) cells. The up-regulation of AT 1 R expression with GPx1 silencing was restored by PDTC. Moreover, treatment with ebselen, a GPX1 mimic, reduced the increased renal AT 1 R expression, Na+-K+-ATPase activity, hydrogen peroxide (H 2 O 2) generation, and the nuclear translocation of NF-κB p65 protein in selenium-deficient RPT cells. Our results demonstrated that long-term selenium deficiency causes hypertension, which is due, at least in part, to decreased urine sodium excretion. Selenium deficiency increases H 2 O 2 production by reducing GPx1 expression, which enhances NF-κB activity, increases renal AT 1 R expression, causes sodium retention and consequently increases blood pressure. [Display omitted] • Long-term selenium deficiency causes hypertension. • Selenium deficiency increases renal AT 1 R expression and sodium retention. • Selenium deficiency elevates NF-κB activity via GPx1/H 2 O 2 pathway. [ABSTRACT FROM AUTHOR]

The stability and electronic properties of the defective nanotube-like fullerenes C 58+10n obtained by removing a 5–6 bond closest to the poles of C 60+10n and their derivatives C 58+10n Cl 8 (n = 1, …, 10) have been investigated by using the density functional theory method. For each system, two isomer structures (the nonclassical fullerene with a heptagon and non-IPR fullerene with two pentagon pairs) and two electronic states (singlet and triplet) were examined. The results show that the non-IPR fullerenes C 58+10n with two pentagon pairs are more stable than their nonclassical isomer with a heptagon. Both the relative energies and the gap energies between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) reveal that the ground state for non-IPR C s -C 68 , C s -C 98 , C s -C 128 , and C s -C 158 is the triplet state, whereas the singlet state is the ground state for non-IPR C s -C 78 , C s -C 88 , C s -C 108 , C s -C 118 C s -C 138 , and C s -C 148 . Further chlorination on non-IPR fullerenes enhances the stability of chlorofullerenes. Especially, C s -C 68 Cl 8, C s -C 98 Cl 8 , C s -C 128 Cl 8 , and C s -C 158 Cl 8 have the most enhance stability both thermodynamically and kinetically exhibiting high negative reaction energies and large HOMO-LUMO gap energies. In addition, the nucleus-independent chemical shift (NICS) analysis shows that the triplet spin state is more aromatic than the corresponding singlet spin state for non-IPR C s -C 68 , C s -C 98 , C s -C 128 , and C s -C 158 . All derivatives C 58+10n Cl 8 are also aromatic. [ABSTRACT FROM AUTHOR]

The thermal stabilities and electronic properties of the three C 56 fullerenes ( #916 C 56 , #864 C 56 , and #913 C 56 ), their chlorinated derivatives, and the corresponding chlorofullerene oxides are investigated and compared using density functional theory (DFT) at the B3LYP/6-31G(d) level. #916 C 56 is the most stable isomer, but #916 C 56 and #864 C 56 possess almost degenerate energies (relative total energy 0.03 kcal/mol). The three experimentally observed C 56 chlorides display the rather high chemical stabilities with the high exothermicities of their chlorination reactions (reaction energy between −38.86 and −48.89 kcal/mol), large HOMO-LUMO energy gaps (between 2.69 and 3.24 eV), and the aromatic character (nucleus independent chemical shifts between −13.6 and −17.6 ppm). Further addition of oxygen atom to the active sites of C 56 chlorofullerenes results in the large stabilities of chlorofullerene oxides. Highly exothermic oxidation addition reactions (reaction energy between −83.66 and −87.24 kcal/mol) along with large HOMO-LUMO gaps (between 2.82 and 3.38 eV) indicate that these three chlorofullerene oxides are stable molecules. Similar to C 56 chlorofullerenes, all investigated chlorofullerene oxides also possess aromatic nature. Hence, #864 C 56 Cl 12 O and #916 C 56 Cl 12 O like the well-known #913 C 56 Cl 10 O can be isolated experimentally. The IR spectra have also been computed to assist future experimental characterization. [ABSTRACT FROM AUTHOR]

A sheet-on-sheet and metal-free graphene/C 3 N 4 /carbon dots (GR/C 3 N 4 /CDots) ternary heterostructure with efficient visible-light photocatalysis for pollutants degradation has been reported. Via a convenient and hydrothermal method, large-sized GR nanosheets can serve as substrate for monodispersed dispersion of C 3 N 4 nanosheets. A subsequent loading of very small amount of CDots (1 wt%, 2–5 nm) onto sheet-on-sheet heterostructure significantly enhance visible-light-driven photoredox performances of catalysts, including oxidation of organics pollutant (RhB, 96.0%) and reduction of heavy metals [Cr(VI), 83.6%]. Excellent catalytic properties of GR/C 3 N 4 /CDots heterostructure can be predominantly ascribed to the intimate interfacial contact among constructing ingredients, increased specific surface area and enhanced light adsorption derived from GR and CDots carbon materials. Particularly, the synergistic sheet-on-sheet interaction between C 3 N 4 and carbon materials (GR and CDots) remarkably accelerate the electrons/holes separation, giving rise to significantly enhanced photoredox performances of GR/C 3 N 4 /CDots in comparison with other counterparts. The synergism effect between organic contaminants and heavy metals also contributed to the efficient performance of GR/C 3 N 4 /CDots, wherein the O 2− and OH were the main active species in the photoredox reactions. This metals-free heterostructure shows favorable photostability in cyclic experiments. We anticipate that our work could provide a classical paradigm for rational design of efficient and visible-light-driven photocatalysts for their sustainable applications in wastewater treatment. [ABSTRACT FROM AUTHOR]

The adsorption of one hydrogen atom on the surface of (5, 5) single-walled silicon carbide nanotube (SiCNT) and (5, 5) SiCNTs with two types of Stone-Wales defects (labeled as SW1 and SW2) has been investigated employing density functional theory. The reaction energy values for the hydrogenation at various sites were obtained at the UB3LYP/6-31G∗ level. It is shown that hydrogen can chemically adsorb on carbon sites or silicon sites on pristine (5, 5) SiCNT, with the reaction energies ranging from −34.7 to −36.6 kcal/mol. The introduction of a SW defect on the (5, 5) SiCNT shows an enhanced interaction of hydrogen with the defective SiCNTs compared to that with the pristine SiCNT. The computed reaction energies range from −39.9 to −67.9 kcal/mol for (5, 5) SW1 and from −33.6 to −69.8 kcal/mol for (5, 5) SW2 SiCNTs. Furthermore, the adsorption of two hydrogen atoms has also been explored. It is found that the system is more energetically favorable for both perfect and SW defective (5, 5) SiCNTs. The electronic properties analysis indicates that single hydrogen atom chemisorption can reduce the HOMO-LUMO gap of corresponding nanotubes, but not for double hydrogen chemisorbed SW defective nanotube. [ABSTRACT FROM AUTHOR]

Highlights: [•] The D 5h and I h isomers of Sc3NC@C80 and Sc3N@C80 have been comparatively studied based on DFT calculations. [•] The encapsulated Sc3NC cluster within the D 5h C80 cage adopts a planar structure as characterized in I h Sc3NC@C80. [•] The adiabatic electron affinity, adiabatic ionization potential and Raman spectra are calculated. [•] D 5h Sc3NC@C80 should be as synthetically approachable as D5h Sc3N@C80. [Copyright &y& Elsevier]

Abstract: With the mature development of international carbon emissions trading market, the establishment of carbon trading market is an inevitable trend in China. This article think about the characteristics of China''s power industry, trying to study carbon emissions trading market mechanisms in the power sector, for providing a reliable basis to establish a national carbon trading market, so as to prepare for docking with the international market in the future. [Copyright &y& Elsevier]

Abstract This paper presents a two-stage optimization method for a coupled capacity planning and operation problem, cast within the economical operation of Regional Integrated Energy System. The first stage optimization of the proposed model represents a regional integrated energy system planner whose purpose is to minimize its energy and environmental cost, while the second stage is an operation problem whose primary role is to achieve the optimal operation scheme of the system. The regional integrated energy system planner pursues best interests by co-optimizing the capacity configuration and power output of individual energy supply module, while the regional integrated energy system maximizes the installed capacity of renewable energy sources and minimizes the environmental costs. To illustrate the advantage of the proposed method, the NSGA-II algorithm and the mixed integer linear programming method are implemented to solve the model based on simulation. Besides, application of the optimization method proposed to the energy infrastructure of a regional integrated energy system in China is discussed, and the results obtained through simulation are compared to the bi-level optimization objectives. The results show that the proposed method is economical and effective in practical application. Highlights • A bi-level optimization model for integrated energy system is presented. • A decentralized optimization method is proposed for solving capacity planning. • Accuracy and economy of capacity planning are improved. • The economic efficiency of the RIES is improved. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we study the existence of nontrivial solutions for a class of second-order difference equations with multiple resonance at both infinity and the origin by applying the critical point theory and Morse theory. [Copyright &y& Elsevier]

A solar air-source heat pump system with phase change energy storage is investigated in this paper. By employing phase change storage in this system, it overcomes the frosting problem in the evaporator and improves the COP of heat pump under the extreme weather condition. The system is constructed and the experiment is carried out in Shijiazhuang. The testing results reveal that the average COP of the heat pump is around 4.92 in the clear days, 1.79 in extreme weather conditions, and 2.12 in the rainy or snow days, which is much higher than the traditional heating mode. Through economic analysis, it is found that the operating cost of the whole heating season is around 22.5% of the oil-fired boiler, 55.4% of the gas boiler, 27.1% of the electric boiler, and 65.6% of the air source heat pump. With the help of phase change storage, solar energy and air source can be utilized to the maximum extent to achieve the purpose of energy-saving and emission reduction in the extremely cold area. [ABSTRACT FROM AUTHOR]

Multi energy demand response is an important measure to achieve the economic and efficient operation of the integrated energy system (IES), which is of great significance to promote the sustainable development of the IES. The concept of demand response (DR) is extended to IES, and a double objective operation optimization model of IES considering integrated demand response (IDR) mechanism is proposed. Firstly, based on the electro-thermal IES, this paper proposes a demand response mechanism considering electric load and thermal load. According to the load composition (transferable load, reducible load, adjustable thermal load), the load management strategy is established. Then, based on the DR mechanism of electro-thermal IES, a multi-objective operation optimization model is established for the first time, which takes the economic benefits and comprehensive energy efficiency as the objective function. The model involves the equipment constraint in the process of energy production and energy transmission. The relationship between total operation cost and comprehensive energy efficiency of electro-thermal IES is analyzed in the part of Data, Simulation Results and Analysis. Finally, the results show that the model effectively improves the economic benefits and comprehensive energy efficiency of IES, and reduces the pollutants emissions to a certain extent. • The information and energy flow framework of an integrated energy system is proposed. • An integrated demand response mechanism considering load composition is established. • A dual objective operation optimization model of integrated energy system is established. • The model aims at economy and comprehensive energy efficiency. • The model can improve the economic, efficiency and environmental benefits of the system. [ABSTRACT FROM AUTHOR]

Through the coordination and complementarity of multiple energy sources, the optimal capacity planning of integrated energy system under limited financial constraints can promote the local absorption of renewable energy, realize the optimal utilization of resources and improve the utilization rate of comprehensive energy. Aiming at the integrated energy system formed by multi-energy coupling, this paper adopts three investment restraint schemes, simulates the economic operation of the system based on typical daily load characteristic curves in different seasons, and establishes an optimal capacity allocation model of the integrated energy system taking into account the investment cost restraint and minimizing the total annual cost and carbon dioxide emissions. Strength Pareto Evolutionary Algorithm 2 (SPEA2) and Technology for Order Preference by Similarity to an Ideal Solution (TOPSIS) are used to optimize the solution. Finally, a park in Beijing is taken as an example to verify the model optimization results and the actual results. The deviation of the target results is less than 5%. This study realizes the scientific capacity allocation of integrated energy system, and provides theoretical basis and technical support for the planning and design of integrated energy system. • Capacity planning optimization under different equipment investment constraints. • Bi-level model framework for universal capacity planning optimization. • The model of multi-objective capacity planning considering economic-environmental cost. • Three schemes are simulated and compared, and sensitivity analysis is carried out. [ABSTRACT FROM AUTHOR]

• A RIES energy network modeling and operation problem is studied. • An operation optimization model considering ladder environmental trading is established. • The optimization of the energy network is studied by optimizing the EH in the system. • The economic and environmental benefits of the system could be realized. The energy network is a hub center connecting the energy supply side and the energy demand side, which has high flexibility. At the same time, energy hub is the key to coupling different energy networks. Therefore, from the optimization of the output of the energy hub to the optimization of the coordinated operation state of the multi-energy network is the core of the regional integrated energy system operation optimization research. This paper focuses on the operation optimization of regional integrated energy systems based on modeling of Electricity-Thermal-Natural Gas Network. Firstly, a general model of Electricity network, Natural Gas network, and Thermal network is established, on this basis, according to the coupling mechanism of multi-energy network, a comprehensive model of Electricity-Thermal-Natural Gas coupling system is established. Secondly, considering the constraints such as energy balance and transmission power of external network, an economic dispatching model of regional integrated energy system considering ladder carbon trading mechanism is established with the objective of minimizing economic cost. Thirdly, Fruit Fly Optimization Algorithm is used to solve the economic dispatch model, and the optimization results of the energy hub are obtained. Combined with the general energy network model, the optimization results of each energy network are further obtained according to the characteristics of energy balance and energy flow transmission of the system, including equipment output, gas turbine efficiency, thermal medium velocity, etc. Finally, in order to illustrate the advantages of this method, "Following power load", "Following heat load", and "Optimal scheduling" are set up in the simulation, and the simulation results show that the total operation cost of "Optimal scheduling" mode is reduced by 8.44% and the environmental emission is reduced by 15.03% compared with the other two modes, and the technical and economic characteristics of "Optimal scheduling" mode have strong advantages in the three modes. [ABSTRACT FROM AUTHOR]