Mesoporous Fe-doped In2O3 nanorods derived from metal organic frameworks for enhanced nitrogen dioxide detection at low temperature

Mesoporous Fe-doped In₂O₃ nanorods derived from metal-organic frameworks (In/Fe-MIL-68s) were synthesized for NO₂ detection. The morphologies, structures and NO₂ gas-sensing performances of the Fe–In₂O₃ nanorods were systematically investigated. Texture characterizations demonstrate that the as-prepared Fe–In₂O₃ nanorods show rich porous structures, high specific surface areas and reduced grain sizes. Gas-sensing measurements display that the Fe–In₂O₃ nanorods derived from In/Fe-MIL-68s with the Fe(Ⅲ) content of 5 mol.% (Fe(5)-In₂O₃) exhibit high response (82) and short response/recovery time (70/65 s) towards 2 ppm NO₂ at 80 °C compared with their counterparts. Besides, superior selectivity and good stability are observed. The sensing mechanism studies reveal that the improved gas-sensing performances are attributed to the decrease in the gran size, the formation of rich oxygen vacancies and band gaps narrowing caused by Fe(Ⅲ) doping. Therefore, this work indicates that the Fe–In₂O₃ nanorods derived from metal-organic frameworks precursors can be a promising candidate for NO₂ detection.     

Switching the Mode of Cell Death between Apoptosis and Autophagy by Histone Deacetylase 6 Inhibition Levels

Inhibition of histone deacetylase (HDAC) has been demonstrated to be an effective strategy for cancer treatment. In this work, we have developed a new agent Ir-VPA , which exhibits the cell death mode switching between apoptosis and autophagy due to the distinct level of HDAC6 inhibition. Ir-VPA indicates the best anticancer activity to HeLa cells, and could be hydrolyzed due to the high expression of the esterase in HeLa cells. Ir-VPA could accumulate in nuclei, induce severe DNA damages and cell cycle arrest at G2/M phase. The anticancer mechanism of Ir-VPA to HeLa cells was dependent on the HDAC6 inhibitory performance, as the caspase dependent apoptosis at low concentration (IC₅₀) and autophagy with the autophagy flux blockage at high concentration (2×IC₅₀). This is resulted from the distinct inhibitory levels of HDAC6, as moderate/complete inhibition at the concentration of IC₅₀/2×IC₅₀.In the presence of autophagic inhibitor chloroquine, the apoptotic population elevated from 32.7 % to 61.7 %, indicating that Ir-VPA could activate apoptotic process through the autophagolysosome fusion inhibition. Ir-VPA also exhibits excellent antiproliferative behavior to 3D HeLa multicellular tumor spheroids (MCTSs). This work not only provided a new HDAC6 inhibitor and novel anticancer mechanism for the effective treatment of cervical cancer, but also demonstrated the strategy to conjugate the metal fragment with active organic drug to enhance the anticancer performance.     

Effect on structure,stability, and H+ irradiation on Nd3+/Ru4+-loaded iron phosphate glass for nuclear applications

Nuclear energy generation technology is critically linked with the safe disposal of radioactive waste. In this context, iron phosphate glass (IPG) is gaining predominance as nuclear waste vitrification matrix that necessitates a thorough study on the effect of the loading of various nuclear fission waste materials in it. In this study, the effect of the loading of Nd³⁺ (which acts as a surrogate for radioactive curium (Cm)) and Ru⁴⁺ (which is a fission product of ²³⁵U) in IPG has been assessed. The optimum loading of Nd³⁺/Ru⁴⁺ leading to the formation of homogenous melt has been ascertained via powder X-ray diffraction and scanning electron microscopy techniques. The modification in the Fe³⁺/Fe²⁺ ratio in IPG and the consequent change in its average coordination number with Nd³⁺/Ru⁴⁺ loading has been deduced from the Mössbauer studies. Local structure analysis has been done using X-ray absorption spectroscopy at Nd/Ru/Fe K-edge (as applicable) for all the single and co-loaded IPG samples. All the co-loaded samples show enhanced glass stability and glass forming ability compared to unloaded IPG which has been ascertained via detailed thermal studies. The variation in IPG network structure on the addition of Nd₂O₃ and RuO₂ has been ascertained through spectroscopic techniques like Fourier transform infrared (FTIR) and Raman. The base glass and a few representative homogenous single and co-loaded IPG samples have been irradiated with 4.5 MeV proton beam to simulate the hosting of radioactive elements and the radiation effect on glass structure has been ascertained using FTIR and Raman spectroscopies. The suitability of IPG as nuclear waste vitrification matrix for Nd³⁺ and Ru⁴⁺ is established through all the above analyses.     

Thermoplastic Sizing of Carbon Fibres in High Temperature Polyimide Composites

Thermoplastic sizing of various carbon fibres has been evaluated as a means of controlling the microcracking resistance, transflexural strength (TFS), and thermo-oxidative stability (TOS) of PMR-15 matrix composites. Four different fibre/thermoplastic size combinations were selected for this study, based on their higher TOS than appropriate controls. Data are presented for the transverse microcrack (TVM) density/inch, and the subsequent delamination of [0,90]_4s laminates induced by thermal cycling (-196 to 350°C for 20 cycles). Results for composite TFS, conditioned TFS (after heating in air at 350°C), and TOS (350°C and 316°C) are also reported. One fibre/thermoplastic size combination gave both good microcracking resistance, and significantly improved TOS, in composite when compared with current commercially-available material.     

Selectivity enhancement during formaldehyde synthesis from methanol by in situ CH3I addition

The effect of CH₃I on the formaldehyde synthesis from methanol over a polycrystalline silver catalyst was investigated at temperatures up to 993 K. While the conversion of both CH₃OH and O₂ were reduced, the selectivity to HCHO increased and to CO₂ decreased after treating the Ag catalyst with CH₃I. A notable observation drawn from a long-time operation indicates the CH₃I treatment strongly restrained the formation of HCOOH that had gradually increased with time-on-stream (TOS). It must be noted that the formaldehyde yield did not increase, but that the suppression of formic acid may make the treatment interesting nevertheless. Finally, it was found that the iodide-induced change of the reaction performance was reversible. All observations may well be explained with the assumption of an iodide-induced re-population with different oxygen species on the silver surface.     

Comparison of the effects of different retention appliances on the oxidant–antioxidant system

The aim was to compare oxidative stress (OS) levels with different types of retention appliance. Thirty orthodontic patients were divided into three groups: Group 1 (Essix retainer), Group 2 (lingual retainer with stainless steel retainer wire), and Group 3 (lingual retainer with fiber-reinforced material). OS was assessed in the subjects’ saliva. Saliva samples were taken from the patients at T₀ (before using the retention appliance), T₁ (first month of retention), and T₂ (third month of retention). The specimens were investigated to detect changes in total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI). TAS values in Group 2 were significantly higher than in Group 3. TOS values in Group 3 were significantly lower than in the other groups. TOS values in Group 2 were lower than in Group 1. OSI values of Group 1 were higher than those in Group 2 or 3. There was no statistically significant difference among the time periods. The type of retention appliance affected OS values. A fiber-reinforced material may have a lower OSI. OS or products can affect some systemic disease; therefore, the selection of the retainer will be important on these patients.     

Morin,a Flavonoid from Moraceae,Induces Apoptosis by Induction of BAD Protein in Human Leukemic Cells

Evidence suggests that phytochemicals can safely modulate cancer cell biology and induce apoptosis. Here, we investigated the anti-cancer activity of morin, a flavone originally isolated from members of the Moraceae family in human leukemic cells, focusing on apoptosis. An anti-cancer effect of morin was screened with several human leukemic cell lines. U937 cells were most sensitive to morin, where it induced caspase-dependent apoptosis in a dose-dependent manner. It also induced loss of MMP (ΔΨ_m) along with cytochrome c release, down-regulated Bcl-2 protein, and up-regulated BAX proteins. The apoptotic activity of morin was significantly attenuated by Bcl-2 augmentation. In conclusion, morin induced caspase-dependent apoptosis through an intrinsic pathway by upregulating BAD proteins. In addition, Bcl-2 protein expression is also important in morin-induced apoptosis of U937 cells. This study provides evidence that morin might have anticancer properties in human leukemic cells.     

A comparative study of the electrogeneration of hydrogen peroxide using Vulcan and Printex carbon supports

A comparative study of two different conductive carbon-black pigments, Vulcan XC-72 R and Printex L6, for the electrogeneration of hydrogen peroxide (H₂O₂) by reducing dissolved oxygen in an alkaline solution was performed. The materials were physically characterized by X-ray diffraction (XRD), Fourier transform infrared attenuated total reflection (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS). XRD shows the presence of SO₂ and ATR-FTIR technique indicates a difference in NO and SO₂ functional groups between the two carbon pigments. XPS indicated presence of SO and NO and more oxygenated acid species on Printex L6. A rotating ring-disk electrode was used for electrochemical analysis of the oxygen reduction reaction (ORR). The results showed that the Printex L6 was better than Vulcan XC-72 R for H₂O₂ production. Results also indicate that the number of electrons transferred in the ORR for Printex L6 and Vulcan XC-72 R were 2.2 and 2.9, respectively, while the percentages of H₂O₂ formed were 88% and 51%. Scanning electrochemistry microscopy images confirmed the higher amount of H₂O₂ formed in the Printex L6 pigment. Printex L6 was shown to be a more promising for H₂O₂ production than Vulcan XC-72 R, while the latter was shown to have more potential for fuel cells.     

Catalyst deactivation and regeneration in low temperature ethanol steam reforming with Rh/CeO2–ZrO2 catalysts

Rh/CeO₂–ZrO₂ catalysts with various CeO₂/ZrO₂ ratios have been applied to H₂ production from ethanol steam reforming at low temperatures. The catalysts all deactivated with time on stream (TOS) at 350 °C. The addition of 0.5% K has a beneficial effect on catalyst stability, while 5% K has a negative effect on catalytic activity. The catalyst could be regenerated considerably even at ambient temperature and could recover its initial activity after regeneration above 200 °C with 1% O₂. The results are most consistent with catalyst deactivation due to carbonaceous deposition on the catalyst.     

Acetylation Enhances the Anticancer Activity and Oral Bioavailability of 5-Demethyltangeretin

A kind of hydroxylated polymethoxyflavone (PMFs) existing in the citrus genus, 5-Demethyltangeretin (5-DTAN), has been reported to possess several bioactivities in vitro and in vivo. The aim of this study was to investigate whether acetylation could enhance the anticancer activity and oral bioavailability of 5-DTAN. PC-3 human prostate cancer cells were treated with tangeretin (TAN), 5-DTAN, and 5-acetylated TAN (5-ATAN), and the results showed that the cytotoxic effect 5-ATAN (IC₅₀ value of 5.1 µM) on the cell viability of PC-3 cells was stronger than that of TAN (IC₅₀ value of 17.2 µM) and 5-DTAN (IC₅₀ value of 11.8 µM). Compared to 5-DTAN, 5-ATAN treatment caused a more pronounced DNA ladder, increased the sub-G1 phase population, and induced G2/M phase arrest in the cell cycle of PC-3 cells. We also found that 5-ATAN triggered the activation of caspase-3 and the progression of the intrinsic mitochondrial pathway in PC-3 cells, suggesting the induction of apoptosis. In a cell wound healing test, 5-ATAN dose-dependently reduced the cell migration, and the expression of matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) was decreased after 48 h of 5-ATAN treatment. Moreover, oral administration of 5-ATAN showed a significantly stronger inhibitory effect on tumor size and tumor weight in tumor-bearing nude mice than those of vehicle or the 5-DTAN group (p < 0.05). Furthermore, pharmacokinetic results showed that single-dose oral administration of 5-ATAN exhibited a higher maximum concentration (Cmax) and area under the curve (AUC) of 5-DTAN in plasma than that of 5-DTAN. More extensive distribution of 5-DTAN to most tissues of mice was also observed in mice treated with 5-ATAN for 7 days. In conclusion, acetylation strongly enhances the anticancer activity and oral bioavailability of 5-DTAN and could be a promising strategy to promote the potential bioactivities of natural products.     

A Series of New Ligustrazine-Triterpenes Derivatives as Anti-Tumor Agents: Design,Synthesis, and Biological Evaluation

A series of novel ligustrazine-triterpenes derivatives was designed, synthesized and screened for their cytotoxicity against five cancer cell lines (Bel-7402, HepG2, HT-29, Hela, and MCF-7) and Madin-Darby canine kidney (MDCK). Current study suggested that most of the ligustrazine-triterpenes conjunctions showed better cytotoxicity than the starting materials. In particular, compound 4a exhibited better cytotoxic activity (IC₅₀ < 5.23 μM) against Bel-7402, HT-29, MCF-7, Hela, and HepG2 than the standard anticancer drug cisplatin (DDP). The cytotoxicity selectivity detection revealed that 4a exhibited low cytotoxicity (IC₅₀ > 20 μM) towards MDCK cells. A combination of fluorescence staining observation and flow cytometric analysis indicated that 4a could induce HepG2 cell apoptosis. Further studies suggested that 4a-induced apoptosis is mediated through depolarization of the mitochondrial membrane potential and increase of intracellular free Ca²⁺ concentration. In addition, the structure-activity relationships of these derivatives were briefly discussed.     

Statistical analysis of the performance of a bi-functional catalyst under operating conditions of LPDME process

Liquid phase direct synthesis of dimethyl ether (LPDME™) under various operating conditions (temperature, H₂/CO molar ratio of feed) was conducted in a mechanically agitated slurry reactor system. Each run was monitored for 60 h time on stream (TOS) in order to confirm the high activity and long-term stability of a bi-functional catalytic system (CuO–ZnO–Al₂O₃/H-MFI-90). Statistical experimental design was applied for determining the optimum operating conditions under which the catalytic system shows the highest performance. A significant improvement in the performance of the bi-functional catalyst was observed when the temperature and H₂/CO molar ratio of feed were increased from 200 to 240 °C and 1 to 2, respectively at a constant pressure of 35 bar and GHSV equal to 1100 mLn/(g-cat h). CO conversion was increased from 9.1 mol% at T = 200 °C and H₂/CO = 1 to 79.6 mol% at T = 240 °C and H₂/CO = 2 and the yield and selectivity of DME also increased from 7.11% to 47.05% and 41.57% to 59.96%, (molar basis) respectively. No significant deactivation has been observed during 60 h TOS at different operating conditions. Furthermore, from the main effect plots and response table results, it was concluded that the most effective factor on activity and stability of bi-functional catalytic system is temperature.     

Effect of nitrogen pretreatment on the skin-core structure of thermal oxidative stabilization polyacrylonitrile fibers

Polyacrylonitrile precursor was pretreated under nitrogen to study the effect of the extent of cyclization of pretreated fibers on the chemical structure, crystal structure and skin-core structure of thermal oxidative stabilization (TOS) fibers. Based on the FTIR spectra, the cyclization degree of pretreated fibers was quantitatively calculated by a combination of peak-fitting and second-derivative operations. Combining the results of wide-angle X-ray diffraction, Raman spectroscopy and scanning electron microscope analysis, pretreatment was beneficial to increase the cyclized structure of TOS fibers, but inhibited the oxidation reactions in the TOS process. As the increase of cyclization degree of pretreated fibers, the oxygen content and crystal size of TOS fibers decreased and the crystal interplanar spacing increased; in the skin layer of TOS fibers, the I_D/I_G ratio increased and brittle fracture area decreased. When the cyclization degree of pretreated fibers was in the range of 10%–35%, the skin-core structure of TOS fibers was weakened, which demonstrated that proper pretreatment before TOS process can improve the skin-core structure.     

Ceruloplasmin as Redox Marker Related to Heart Failure Severity

This study examined ceruloplasmin levels in patients with HFrEF, depending on cardiopulmonary exercise testing (CPET) parameters; a correlation was found between ceruloplasmin (CER) and iron and hepatic status, inflammatory and redox biomarkers. A group of 552 patients was divided according to Weber’s classification: there were 72 (13%) patients in class A (peak VO₂ > 20 mL/kg/min), 116 (21%) patients in class B (peak VO₂ 16–20 mL/kg/min), 276 (50%) patients in class C (peak VO₂ 10–15.9 mL/kg/min) and 88 (16%) patients in class D (peak VO₂ < 10 mL/kg/min). A higher concentration of CER was found in patients with peak VO₂ < 16 mL/kg/min and VE/CO₂ slope > 45 compared to patients with VE/CO₂ slope < 45 (escectively CER 30.6 mg/dL and 27.5 mg/dL). A significantly positive correlation was found between ceruloplasmin and NYHA class, RV diameter, NT-proBNP, uric acid, total protein, fibrinogen and hepatic enzymes. CER was positively correlated with both total oxidant status (TOS), total antioxidant capacity (TAC) and malondialdehyde. A model constructed to predict CER concentration indicated that TOS, malondialdehyde and alkaline phosphatase were independent predictive variables (R² 0.14, p < 0.001). CER as a continuous variable was an independent predictor of pVO₂ ≤ 12 mL/kg/min after adjustment for sex, age and BMI. These results provide the basis of a new classification to encourage the determination of CER as a useful biomarker in HFrEF.     

High-performance LaNi0.6Fe0.4O3-δ-La0.45Ce0.55O2-δ nanoparticles co-loaded oxygen electrode for solid oxide steam electrolysis

Hydrogen production through solid oxide electrolysis cells (SOECs) driven by renewable energy has attracted a lot of attention. Nevertheless, the poor performance of the oxygen electrode is a bottleneck in the implementation of SOECs. This work reports a high-performance LaNi_0.6Fe_0.4O_3-δ-La_0.45Ce_0.55O_2-δ (LNF-LDC) nanoparticles co-loaded (La_0.8Sr_0.2)_0.9MnO_3-δ-Y_0.15Zr_0.85O_2-δ (LSM-YSZ) oxygen electrode. Firstly, the co-synthesized LNF-LDC nano-composite is characterized by XRD, SEM, H₂-TPR and O₂-TPD techniques. Compared with individually synthesized LaNi_0.6Fe_0.4O_3-δ (LNF), the co-synthesized LNF-LDC nanoparticles have a larger amount of oxygen vacancy and higher oxygen mobility due to a strong synergistic effect. Secondly, the LNF-LDC nanoparticles co-loaded oxygen electrode exhibits a higher electrochemical performance than the single LNF loaded LSM-YSZ electrode. Under 800 °C and 50% A.H., the cell with LSM-YSZ@LNF-LDC-4 μL delivers ?1.18 A cm^?2 at 1.3 V, which is 2.03 times higher than the cell with LSM-YSZ@LNF-4 μL. Therefore, co-loading LNF-LDC is a promising method to develop a highly efficient oxygen electrode for solid oxide steam electrolysis.     

The Synergistic Effects of Two Co-catalysts on Zn2GeO4 on Photocatalytic Water Splitting

Zinc orthogermanate was prepared via a hydrothermal method and a remarkable synergistic effect on the photocatalytic activity for overall water splitting was found for Zn₂GeO₄ co-loaded with noble metals (Pt, Rh, Pd, Au) and metal oxides (RuO₂, IrO₂). The photocatalytic activity of Pt-RuO₂/Zn₂GeO₄ for overall water splitting is 2.2 times of Pt/Zn₂GeO₄ and 3.3 times of RuO₂/Zn₂GeO₄. Photocatalytic half reactions evaluation of water splitting for H₂ and O₂ productions shows that Pt plays the major roles in H₂ production and RuO₂ promotes the O₂ production. The roles and valence states of co-catalysts and the mechanism of photocatalytic reaction are discussed.     

Selective Catalytic Synthesis of 2-Ethyl Phenol over Cu1− xCox Fe2O4–Kinetics, Catalysis and XPS Aspects

A systematic study of catalytic ethylation of phenol is carried out with ethanol as a function of feed composition, time on stream (TOS), temperature, and catalyst composition over Cu_{1 ?x} Co _x Fe₂O₄ (x=0.0–1.0) ferrospinel system. Phenol ethylation gives 2-ethyl phenol as a major product under the reaction conditions employed, while its selectivity decreases as temperature and Co-content increases. Compositions containing both Cu and Co (0<x<1) are found to be more efficient for better catalytic performance than the end compositions (x=0 and 1); x=0.5 shows the highest catalytic performance. TOS studies clearly exhibit the stable activity for x≤0.75 for at least 50h. X-ray photoemission spectra (XPS) and X-ray induced Auger electron spectroscopy analysis revealed the partial reduction of metal ions during reaction. Valence band studies clearly show an increase in overlap of metal-ion 3d bands from fresh to spent catalysts by a large decrease in energy gap between them. Cu-rich compositions display a large amount of Cu species on the surface and highlight its importance in the ethylation. High catalytic activity displayed by 0<x<1 emphasizing the importance of both Cu and Co for better catalytic performance.     

Discovery of Quinoline‐Derived Trifluoromethyl Alcohols,Determination of Their in vivo Toxicity and Anticancer Activity in a Zebrafish Embryo Model

In this study the rational design, synthesis, and anticancer activity of quinoline‐derived trifluoromethyl alcohols were evaluated. Members of this novel class of trifluoromethyl alcohols were identified as potent growth inhibitors in a zebrafish embryo model. Synthesis of these compounds was carried out with an sp³‐C?H functionalization strategy of methyl quinolines with trifluoromethyl ketones. A zebrafish embryo model was also used to explore the toxicity of ethyl 4,4,4‐trifluoro‐3‐hydroxy‐3‐(quinolin‐2‐ylmethyl)butanoate ( 1 ), 2‐benzyl‐1,1,1‐trifluoro‐3‐(quinolin‐2‐yl)propan‐2‐ol ( 2 ), and trifluoro‐3‐(isoquinolin‐1‐yl)‐2‐(thiophen‐2‐yl)propan‐2‐ol ( 3 ). Compounds 2 and 3 were found to be more toxic than compound 1 ; apoptotic staining assays indicated that compound 3 causes increased cell death. In vitro cell proliferation assays showed that compound 2 , with an LC₅₀ value of 14.14 μm , has more potent anticancer activity than cisplatin. This novel class of inhibitors provides a new direction in the discovery of effective anticancer agents.     

Ruthenium Complexes Induce HepG2 Human Hepatocellular Carcinoma Cell Apoptosis and Inhibit Cell Migration and Invasion through Regulation of the Nrf2 Pathway

Ruthenium (Ru) complexes are currently the focus of substantial interest because of their potential application as chemotherapeutic agents with broad anticancer activities. This study investigated the in vitro and in vivo anticancer activities and mechanisms of two Ru complexes—2,3,7,8,12,13,17,18-Octaethyl-21H,23H-porphine Ru(II) carbonyl (Ru1) and 5,10,15,20-Tetraphenyl-21H,23H-porphine Ru(II) carbonyl (Ru2)—against human hepatocellular carcinoma (HCC) cells. These Ru complexes effectively inhibited the cellular growth of three human hepatocellular carcinoma (HCC) cells, with IC₅₀ values ranging from 2.7–7.3 μM. In contrast, the complexes exhibited lower toxicity towards L02 human liver normal cells with IC₅₀ values of 20.4 and 24.8 μM, respectively. Moreover, Ru2 significantly inhibited HepG2 cell migration and invasion, and these effects were dose-dependent. The mechanistic studies demonstrated that Ru2 induced HCC cell apoptosis, as evidenced by DNA fragmentation and nuclear condensation, which was predominately triggered via caspase family member activation. Furthermore, HCC cell treatment significantly decreased the expression levels of Nrf2 and its downstream effectors, NAD(P)H: quinone oxidoreductase 1 (NQO1) and heme oxygenase 1 (HO1). Ru2 also exhibited potent in vivo anticancer efficacy in a tumor-bearing nude mouse model, as demonstrated by a time- and dose-dependent inhibition on tumor growth. The results demonstrate the therapeutic potential of Ru complexes against HCC via Nrf2 pathway regulation.