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[Display omitted] • Ce-doped TiO 2 (0 0 1) single-atom (SA) catalyst exhibit superior SO 2 /H 2 O-resistance. • CT(0 0 1)-SA protect Ce site from sulfation/hydration with TiO 2 (0 0 1) as trapping site. • Electron capture behavior of SO 2 /H 2 O cause an electron-deficient state of CT(0 0 1)-SA. • Electron-deficiency promote NH 3 adsorption and suppress secondary sulfation/hydration. • Sulfation/hydration exhibite a "dual-edged sword" effect for NH 3 -SCR on CT(0 0 1)-SA. SO 2 /H 2 O-resistance remains challenges for selective catalytic reduction with NH 3 (NH 3 -SCR). The detailed promotion and/or inhibition effects of sulfation/hydration on cerium-titanium (CT) catalysts for NH 3 -SCR are still controversial. Herein, a series of adsorption characteristics, bonding strengths, electronic effects, and reaction pathways were performed by first-principles density functional theory calculations to explore the structure-performance/resistance of CT catalysts and unravel the effects of sulfation/hydration for NH 3 -SCR. We constructed six CT catalyst structures based on three TiO 2 facets [(0 0 1)/(1 0 1)/(1 0 0)] and two surface configurations [single-atom (SA)/interface (IF)]. CT(0 0 1)-SA could protect the active Ce site from sulfation/hydration with TiO 2 (0 0 1) as SO 2 /H 2 O-trapping site, which was the optimal SO 2 /H 2 O-resistant structure among six CT catalyst structures. An electron-deficient state of CT(0 0 1)-SA was caused by sulfation/hydration through electron capture behavior. From the perspective of reactants adsorption, this electron-deficient state not only promoted the NH 3 /NO adsorption but also suppressed the secondary sulfation/hydration. As for NH 3 -SCR pathways, hydration promoted NH 3 dissociation, N-N coupling, and N-O breaking, but inhibited the H1 transfer (rate-determining step). Sulfation impaired the redox ability of Ce site, promoted H1 transfer and N-O breaking, but inhibited the NH 3 dissociation, N-N coupling, and H2 transfer (rate-determining step). Hence, sulfation/hydration exhibited "dual-edged sword" effects for NH 3 -SCR on CT(0 0 1)-SA via electronic effects. [ABSTRACT FROM AUTHOR]

• An UPLC-MS/MS method of CX3002 in human plasma was established. • The method was fully validated according to the FDA and EMA guidelines. • The developed method was succesfully applied to a clinical pharmacokinetic study. A simple, selective, rapid, and reliable ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed and validated to determine CX3002 in human plasma using CX3002-d3 as the internal standard (IS). After a rapid protein precipitation with acetonitrile (3:1, v/v), the chromatographic separation of CX3002 and IS was performed on a Thermo Hypersil GOLD C18 column (2.1 mm × 50 mm, 1.9 μm) with gradient elution at a flow rate of 0.4 ml/min. Gradient elution was achieved with mobile phase A consisting of water containing 0.1% formic acid and 5 mmol/L ammonium formate and mobile phase B consisting of methanol containing 0.1% formic acid. The detection was performed on AB SCIEX QTRAP® 5500 tandem mass spectrometry in the positive ion mode. Multiple reactions monitoring (MRM) was used for quantitative analysis at transition of m / z 460.3 → 199.3 for CX3002 and m / z 463.3 → 202.3 m / z for IS. The method was fully validated and displayed good linearity over a concentration range of 0.2–400 ng/mL with the correlation coefficient above 0.997. The intra-run and inter-run precision (coefficient of variation, CV) ranged from 0.60%–16.46% and the accuracy bias ranged from −7.09%–9.75%. The mean IS-normalized extraction recovery ranged from 98.30% to 104.52%. The CV(%) of IS-normalized matrix factors at the low and high QC concentration were 4.09% and 1.68%, respectively. The storage stability under different conditions was in accordance with the bioanalytical guidelines. The method was successfully applied to the pharmacokinetic study of CX3002 (30 mg) in healthy Chinese subjects. [ABSTRACT FROM AUTHOR]

• A portable optical fiber-based LSPR biosensor was successfully developed to determine the concentration of ZEN. • This tip LSPR biosensor could be regenerated by simple cutting and polishing the end of the used facet of optical fiber. • Key factors, the distribution of gold nanoparticles, pH and density of ZEN aptamer, were optimized in the LSPR biosensor. • This LSPR biosensor displayed an excellent ZEN detection performance in real sample. With the continuous improvement of people's living standards, food safety issues have gradually become one of the main concerns. Rapid and accurate detection of zearalenone (ZEN) in food has attracted broad research interest. In this work, a low-cost, portable, and reusable optical fiber-based localized surface plasmon resonance (LSPR) biosensor for ZEN was developed. Gold nanoparticles around 25 nm were synthesized and coated on the cross-section of the end of an optical fiber, and then the ZEN nucleic acid aptamer was modified to form the LSPR biosensor for ZEN detection. Results showed that there was a good relationship between ZEN concentrations and the redshifts of LSPR peak in the range of 1 ∼ 480 ng/mL, the limit of detection was 0.102 ng/mL. Moreover, the sensing interface could be easily regenerated by cutting and polishing the end of the optical fiber, indicating that the LSPR biosensor was reusable. It also has exceptional high selectivity for ZEN and good recovery and repeatability, which has a good prospect for the on-site ZEN monitoring. [ABSTRACT FROM AUTHOR]

Focuses on the classification of Reimannian symmetric spaces given by É. Cartan. Realization of exceptional classical domains; Determination of holomorphic automorphism group; Realization of indecomposable symmetric Seigel domains.

• Optimality principle of the cascade reservoirs joint optimal operation is discussed. • A two-stage optimal problem similar to the POA optimal process is constructed. • The existence of the monotonic principle is proved by numerical simulation. • Two typical cascade reservoirs are analyzed by using the optimal principle. The joint optimal dispatching of cascade hydropower stations aims to maximize economic benefits while satisfying various constraints. However, numerous studies have failed to acknowledge the significance of the intrinsic optimization principle and lack discussion on this issue. This study started with a mathematical principle analysis of the optimization problem and studied the optimality principle puzzle of the joint optimal dispatching of cascade hydropower stations. First, a two-stage optimization problem was constructed to describe the relationship between the variation in discharge and the incremental function of the total energy generation of the reservoir. Subsequently, the first and second derivatives of the cascade total generating capacity increment to cascade reservoir discharge variation were derived, and the existence condition of monotonically decreasing the first derivative was proposed. Moreover, the monotonicity principle was proven through numerical simulations by comparing the optimization results of POA and the monotonicity principle coupled IPOA in the cascade hydropower stations operation of the Jinsha River, it was found that in terms of power generation and computational efficiency, IPOA is superior to POA. Finally, using this optimization principle, the optimal operation mode of the two typical cascade reservoirs was analyzed in the case studies. The example results show that the proposed optimal principle can theoretically analyze and clarify the optimal operation mode of cascade reservoirs, and the operation modes of the two typical cascade reservoirs can provide guidance and reference for the operation modes of cascade reservoirs in real life. [ABSTRACT FROM AUTHOR]

• Major SO 2 deactivation mechanisms of Ce-based catalysts are summarized. • The positive and negative effects of metal sulfates on Ce-based catalysts are discussed. • Regulatory measures against SO 2 poisoning are proposed. Selective catalytic reduction with ammonia (NH 3 -SCR) technology is an effective process for industrial flue gas denitrification. Ce-based catalysts are widely studied due to their excellent redox properties and superior oxygen storage and release capacity (OSC). However, the unavoidable presence of SO 2 and H 2 O in the coal-fired flue gas leads to their limitations in the application of denitrification technology. SO 2 poisoning not only causes the formation of metal sulfates, but its synergistic interaction with H 2 O also results in the deposition of ammonium sulfate species. All this leads to severe deactivation of Ce-based catalysts in NH 3 -SCR. The development of Ce-based catalysts with excellent sulfur and water resistance is an urgent requirement for SCR technology. This review elucidates the poisoning mechanism of SO 2 , and analyzes the effects of metals/non-metals modification and structural optimization on the anti-SO 2 performance of Ce-based catalysts. This provides the reference and guidance for the subsequent development of Ce-based catalysts resistance to SO 2. [Display omitted] [ABSTRACT FROM AUTHOR]

Phosphoinositide 3-kinase (PI3K) pathway, controlling diverse functions in cells, is one of the most frequently dysregulated pathways in cancer. Several negative regulators have been reported to intricately constrain the overactivation of PI3K pathway. Phosphatidylinoinosidine-3-kinase interacting protein 1 (PIK3IP1), as a unique transmembrane protein, is a newly discovered negative regulator of PI3K pathway. PIK3IP1 negatively regulates PI3K activity by directly binding to the p110 catalytic subunit of PI3K. It has been reported that PIK3IP1 is frequently low expressed in tumors and autoimmune diseases. In tumor cells and impaired cardiomyocyte, PIK3IP1 inhibits cell proliferation and survival. Consistently, the expression of PIK3IP1 is related with the condition of cancer. In addition, PIK3IP1 inhibits the inflammatory response and immune function via maintaining the quiescent state of immune cells. Thus, low expression of PIK3IP1 represents the severe condition of autoimmune diseases. PIK3IP1 is regulated by transcription factors, epigenetic factors or micro-RNAs to facilitate its normal function in different cellular contexts. This review integrates the total findings on PIK3IP1 in different disease, and summaries the structure, biological functions and regulatory mechanisms of PIK3IP1. [ABSTRACT FROM AUTHOR]

Enhancing the resistance of SCR (Selective Catalytic Reduction) catalyst to K poisoning can be effectively achieved through modification. This study investigated the impact of transition metal modification on improving the ability of Ce/TiO 2 (CT) catalysts to resist K poisoning by DFT (Density functional theory) calculations. Mo-, Nb-, and W-doping could effectively suppress the adsorption of K. O v (oxygen vacancy) formation and hydrogenation reactions were both facilitated due to the modification of Cu, Co and Sb. The Cu-doping had a significant contribution to the adsorption of NH 3 and NO, and showed the best resistance to K poisoning in the adsorption of reactive species. Additionally, Cu-doping decreased the energy barriers for NH 3 dehydrogenation, NH 2 NO generation and decomposition, and NO 2 formation on CT catalyst, and weakened the inhibition effect of K on the above elementary reactions. Consequently, this provided an effective improvement in the k-poisoning tolerance of the CT catalysts. [Display omitted] • A method for screening modified elements based on DFT calculation was reported. • M-doping benefits hydrogenation, oxygen vacancy formation, and adsorption of NH 3 /NO. • M-doping mitigated the toxic effect of K in adsorption energy and energy barrier. • The modification effect of Cu was better than that of Co, Sb, Mo, Zr, Nb, W. • CCuT extremely weakened the inhibition of E-R and L-H mechanisms by K. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nb doping enhances the acidity of Ce-Ti catalysts and anti-poisoning performance. • Zn prefers to adsorb around Nb and the Ce sites are further protected by Nb. • Zn species reduce the specific surface area and occupy acidic sites of CNT. • Anions creates new NH 3 adsorption sites but the activation of adsorbed NH 3 is more difficult. The effect of different Zn species (ZnSO 4 , ZnCl 2 , and ZnO) on Nb-doped Ce-Ti catalyst (CNT) was explored with XRD, N 2 physisorption, NH 3 -TPD, H 2 -TPR, XPS, in situ DRIFTS and DFT calculation. The experimental results show that the deactivation rate of CNT by different Zn species was in the order: CNT-ZC > CNT-ZO > CNT-ZS. Nb doping enhanced the acidity of Ce-Ti catalyst and protected Ce active sites from different Zn species. After different Zn species were loaded on CNT, its specific surface area decreased, and the acid sites were occupied. The results from in situ DRIFTS demonstrated that, after anion poisoning, anions (SO 4 2-, O2–, and Cl-) would create new NH 3 adsorption sites while theoretical calculations also indicated that NH 3 adsorption was enhanced by the poisoning of anions, but the activation of adsorbed NH 3 was more difficult. Finally, in situ DRIFTS reveals that the SCR reaction on CNT is still under both E-R and L-H mechanisms. [ABSTRACT FROM AUTHOR]

[Display omitted] • The effect of different metal doping (Cu, Co, Ce, Fe) on the oxidation performance of α-MnO 2 toluene was revealed. • MnCu exhibits excellent catalytic activity, thermal stability, and resistance to H 2 O due to the optimal crystal structure, appropriate Mn3+/Mn4+ proportion, and superior redox properties. • The generation of oxygen vacancies in MnCu promotes the Mn3+ ↔ Mn4+ interconversion and lattice oxygen (O lat) migration. • The highest lattice oxygen (O lat) mobility in MnCu accelerates the deep oxidation of toluene. • The balance between toluene adsorption and deep oxidation is needed to ensure that toluene can be oxidized continuously. α-MnO 2 doped with four metals (Cu, Ce, Co, Fe) were prepared via a redox co-precipitation method. MnCu exhibited the highest activity and the temperature required for achieving 90% toluene conversion was 224℃ at a weight hourly space velocity of 30000 mL·g−1·h−1. Moreover, MnCu possessed outstanding thermal stability and resistance to H 2 O. The optimal crystal structure, appropriate Mn3+/Mn4+ proportion, and superior redox properties of MnCu contributed to the generation of oxygen vacancies and the highest lattice oxygen (O lat) mobility. Both surface and bulk lattice oxygen consumed in MnCu can be supplemented promptly by gaseous oxygen. Therefore, a balance between toluene adsorption and deep oxidation was built in MnCu to ensure the continuous oxidation of toluene. Although the abundant surface defects and a relatively active surface lattice oxygen accelerated the adsorption and activation of toluene over MnFe, it exhibited the poorest activity. This was because the deep oxidation of toluene was inhibited owing to poor lattice oxygen migration. The adsorbed toluene and part intermediates might cover the catalyst surface preventing the continuous oxidation of toluene. This further illustrated that the deep oxidation of toluene was much more important than the adsorption for the design of MnO 2 -based mixed oxide catalysts. [ABSTRACT FROM AUTHOR]

This study found NRG1 upregulation in esophageal cancer due to gene amplification, promoting tumor growth and metastasis. Afatinib inhibits NRG1-overexpressed ESCC effectively. [Display omitted] Esophageal squamous cell carcinoma (ESCC) is a highly aggressive tumor with significant heterogeneity in incidence and outcomes. The role of Neuregulin 1 (NRG1) in ESCC and its contribution to aggressiveness remain unknown. This study aims to investigate the functions and molecular mechanisms of NRG1 in ESCC as well as the treatment strategy for ESCC with overexpression of NRG1. We firstly demonstrated the upregulation of NRG1 and a negative correlation trend between patients' overall survival (OS) and the expression level of NRG1 in esophageal cancer. And then we found NRG1 promoted cell proliferation, migration, inhibited apoptosis, and accelerated tumorigenesis and metastasis in ESCC using cell lines and xenograft models. Furthermore, we discovered that NRG1 activated the NF-κB/MMP9 signaling pathway, contributing to the metastatic phenotype in ESCC. Finally, we show that afatinib (FDA approved cancer growth blocker) could inhibit ESCC with overexpressed NRG1 and down-regulation of NRG1 along with afatinib treatment provides higher efficient strategy. This study uncovers the critical role and molecular mechanism of NRG1 in ESCC tumorigenesis and metastasis, suggesting its potential as a novel biomarker for ESCC treatment. [ABSTRACT FROM AUTHOR]

• Na poisoning mechanism on Ce/TiO 2 (001) surface was studied by DFT calculations. • Ce/TiO 2 (001) surface was easily poisoned due to the high affinity with Na. • Na doping changed the catalyst structure and reduced the reactivity of the surface. • Na poisoning significantly increased the energy barrier of elementary reactions. • Both Eley-Rideal and Langmuir-Hinshelwood mechanisms were inhibited. The presence of alkali metal Na in flue gas can significantly impair the reactivity of Ce/TiO 2 (CT) SCR (Selective Catalytic Reduction) catalyst. This study investigates the deactivation mechanism of Na on the Ce/TiO 2 catalyst using Density Functional Theory (DFT) calculations, focusing on the adsorption of surface species and the pathway of elementary reaction. Due to the high affinity between Na atom and the catalyst surface, Na poisoning readily occurs on Ce/TiO 2 (001) surface. The presence of Na on the catalyst surface hampers hydrogenation, oxygen vacancy formation, and NH 3 adsorption, while also reducing the catalyst's acidity and reducibility. Additionally, Na impedes the NH 3 dehydrogenation reaction, as well as the formation and decomposition of NH 2 NO and the dissociation of O 2 on the catalyst surface, thereby inhibiting the NH 3 -SCR reaction. The inhibition of NO 2 formation further affects the fast SCR reaction, which may explain the low-temperature deactivation of the catalyst. [Display omitted] [ABSTRACT FROM AUTHOR]

CeO 2 /TiO 2 catalyst is a promising material for realizing the integration of denitrification and mercury removal to reduce mercury emissions. Oxidation mechanism of Hg0 on CeO 2 /TiO 2 (001) surface in the presence of HCl and O 2 was studied by density functional theory (DFT). The results indicated that Hg0 was physically adsorbed on CeO 2 /TiO 2 (001) surface. As an important intermediate, HgCl was adsorbed on the surface of CeO 2 /TiO 2 (001) utilizing enhanced chemisorption, while the adsorption energy of HgCl 2 was only −57.05 kJ/mol. In the absence of HCl, mercury oxidation followed the Mars-Maessen mechanism with a relatively high energy barrier, and the product (HgO) was difficult to desorb, which hindered the reaction process. When HCl existed, reactive chlorine (Cl*) would be produced by the dissociation of HCl, and the mercury oxidation would follow the Langmuir-Hinshelwood mechanism. The co-existence of HCl and O 2 had no significant effect on the adsorption of Hg0, but reduced the reaction energy barrier and the final product (HgCl 2) was more easily desorbed from the catalyst surface. In addition, two complete cyclic reaction pathways for catalytic oxidation of Hg0 on CeO 2 /TiO 2 (001) surface were constructed to clarify the detailed reaction process. [Display omitted] • Hg0 oxidation mechanism on CeO 2 /TiO 2 (001) surface was studied by DFT calculation. • Difficult formation and desorption of HgO result in low oxidation efficiency. • HCl and O 2 could significantly reduce the reaction energy barrier. • Hg0 oxidation by HCl followed Langmuir-Hinshelwood mechanism. • Two complete catalytic cycles were constructed to understand the reaction pathway. [ABSTRACT FROM AUTHOR]

• MeJA induces lateral root (LR) development in Malus hupehensis. • MeJA inhibits plant height and stem diameter of Malus hupehensis seedlings. • MeJA and auxin have a combined role in the induction of LR development. • Specific genes and pathways were presented in meja-mediated LR development. Malus hupehensis is regarded as a superior rootstock in China. In this study, in order to investigate the mechanism by which MeJA promotes and affects lateral root (LR) development, M. hupehensis seedlings were treated with exogenous applications of 1 μM methyl-jasmonate (MeJA). Results indicated that MeJA treatment promoted LR development, but inhibited shoot development. MeJA treatment increased the levels of both endogenous auxin (IAA) and zeatin-riboside (ZR), and reduced gibberellin (GA 1+3). Additionally, a significant upregulation in the expression of MdCOI1, MdMYC2 and MdJDL1 were also observed in response to the MeJA treatment. Although transcript levels of key IAA synthesis related genes increased, but those genes related to IAA transport were declined, which corresponded with higher IAA levels in the MeJA-treated samples. The expression of MdIAA5 , which is a negative regulator of MdARF7 , was dramatically downregulated in MeJA-treated apple seedlings, resulted in elevated expression of MdLBD16 and MdLBD29. Additionally, the expression of MdCYCD3;1 and MdCYCP4;1 were induced, which in turn increased LR development. Collectively, MeJA treatment increased the number of LRs and other growth characteristics. [ABSTRACT FROM AUTHOR]