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Indenofluorene, which consists of a 6-5-6-5-6 fused-ring structure, is a semiconducting molecule with possible applications in optoelectronic devices. Bulk crystal structures, molecular front orbitals, and on-surface polymerized indenofluorene have recently been studied, but self-assembled structures on the surface have not yet been reported. Here, we report the array structure of 2,8-dibromoindeno[1,2-b]fluorene-6,12-dione on Au(111) studied using scanning tunneling microscopy. We proposed an alternating-tread stair structure as the molecular model for the monolayer molecular islands, which show strong shape anisotropy. The model can be explained by four O⋅⋅⋅H hydrogen bonds and one Br⋅⋅⋅Br halogen bond per molecule, as supported by density functional theory calculations. Although they prefer intermixed heteroprochiral structures in bulk layers, our study shows that these molecules can form phase-separated homoprochiral structures on the surface, leading to potential applications in molecular chiral separation.

Support- and sulfide-free cobalt molybdenum catalysts are prepared via different synthetic procedures for catalytic deoxygenation of oleic acid under inert (N2) and solvent-free conditions. Among the tested catalysts, the CoMo catalyst prepared via a sol-gel method achieves the highest catalytic performance, namely, 88.9% oleic acid conversion, with 48.1% C9–C17 selectivity, and 69.6% oxygen removal rate, owing to its excellent physical properties. Additionally, oxygen vacancy is formed in CoMo catalyst during sol-gel synthesis process and it also effect on the catalytic activity. Examination of the deoxygenation reaction over pre-reduced catalysts reveals that the CoMoO4 species is the active species in the CoMo catalysts. The fuel properties of the resultant products are affected strongly by the catalytic performances of the CoMo catalysts. The biofuel produced using the CoMo catalyst prepared via the sol-gel method showed the highest calorific value (10,119 cal/g) and the lowest viscosity (31.5 cP), and, consequently, this CoMo catalyst exhibits the highest catalytic activity and has significant potential for application in biofuel production.

A one-step reverse precipitation method has been developed to prepare nano-sized ceria (CeO2) support with controlled physicochemical properties for low temperature water-gas shift (LT-WGS) reaction. The nano-sized CeO2 support prepared by reverse precipitation method has a high Brunauer-Emmett-Teller (BET) surface area of 162.8 m2/g. To compare catalytic activity with that of CeO2 prepared by normal precipitation method, 5 wt% Cu was employed as the active metal, coupled to the CeO2 support. The catalytic activity of CeO2 supported Cu catalyst prepared by reverse precipitation method was evaluated for the first time in LT-WGS reaction. Notably, the CeO2 – R supported Cu catalyst, prepared by reverse precipitation method, showed higher CO conversion and turnover frequency (TOF) values than CeO2–N supported Cu catalyst prepared by normal precipitation method.

The Ce/Zr ratio of Pd/Ce-ZrO2 catalysts was systematically changed in order to investigate the effect of oxygen vacancy concentration on their decarboxylation activityunder solvent-free conditions for potential sustainable petroleum like biodiesel production. Pd/Ce0.5Zr0.5O2 exhibited the highest catalytic activity from all other tested catalysts because it contained the highest oxygen vacancy concentration and Pd dispersion, as shown by the X-ray photoelectron spectroscopy, Raman spectroscopy, and CO-chemisorption data. A catalyst deactivation study also showed that both the Pd dispersion and the oxygen vacancy concentration influences the catalytic activity.The catalyst deactivation was found to occur mainly due to Pd sintering, decreases in the BET surface area and Pd dispersion, and partially due to the loss of oxygen vacancies.

Cancer is the second leading cause of death worldwide and has become a global burden. It has long been known that inflammation is related to cancer, as inflammatory components have been identified in the tumor microenvironment and support tumor progression. Among the key inflammatory mediators, leukotrienes were found to be involved in cancer development. In particular, leukotriene B4, which is converted from leukotriene A4 by leukotriene A4 hydrolase (LTA4H), has been implicated in several types of cancer. In addition, LTA4H has attracted attention because of purported roles in inflammation and cancer development. Herein, we review the history of LTA4H, its emerging roles in cancer development, and the development of LTA4H inhibitors in cancer prevention and therapy.

We herein report the preparation of ceria (CeO2) via a simple precipitation method for use as a catalyst support in the water-gas shift (WGS) reaction. More specifically, we optimized the titration time required to obtain highly active CeO2-supported catalysts for the WGS reaction. As such, Cu was employed as the active metal coupled with the CeO2 support. Notably, the CeO2–0 supported Cu catalyst (where the precipitant was immediately injected into a cerium nitrate solution) exhibited the highest CO conversion at a gas hourly space velocity of 36,050 h−1. This high catalytic activity of the Cu/CeO2–0 catalyst was mainly due to its high Brunauer-Emmett-Teller (BET) surface area, enhanced Cu dispersion, high number of oxygen vacancies, and enhanced reducibility.

Mitochondrial DNA (mtDNA) mutations are often observed in various cancer types. Although the correlation between mitochondrial dysfunction and cancer malignancy has been demonstrated by several studies, further research is required to elucidate the molecular mechanisms underlying accelerated tumor development and progression due to mitochondrial mutations. We generated an mtDNA-depleted cell line, ρ⁰, via long-term ethidium bromide treatment to define the molecular mechanisms of tumor malignancy induced by mitochondrial dysfunction. Mitochondrial dysfunction in ρ⁰ cells reduced drug-induced cell death and decreased the expression of pro-apoptotic proteins including p53. The p53 expression was reduced by activation of nuclear factor-κB that depended on elevated levels of free calcium in HCT116/ρ⁰ cells. Overall, these data provide a novel mechanism for tumor development and drug resistance due to mitochondrial dysfunction. [BMB Reports 2018; 51(6): 296-301].

We prepared a series of alkali (Na and K) and alkaline earth metal (Ca and Ba) promoted Co/CeO2 catalysts to investigate the effect of the promoter on the catalytic performance of the catalyst in the high-temperature water-gas shift (WGS) reaction of waste derived synthesis gas. Interestingly, alkali metal promoted catalysts deactivated rapidly compared to alkaline earth metal promoted catalysts. Alkaline earth metal promoted catalysts showed relatively higher stability (> 50 h) even at a very high gas hourly space velocity of 143,000 h−1. X − ray diffraction (XRD) and transmission electron microscopy (TEM) results reveal that the higher stability of the alkaline earth metal promoted catalysts was due to the strong resistance to sintering, showing a relatively small crystallite size of metallic cobalt compared to the alkali metal promoted catalysts after WGS reaction.

Steam reforming of methane (SRM) is conducted using a series of Ni-MgO-Al2O3 catalysts for direct internal reforming (DIR) in molten carbonate fuel cells (MCFCs). Ni-MgO-Al2O3 catalysts are prepared by the homogeneous precipitation method with a variety of MgO loading amounts ranging from 3 to 15 wt%. In addition, each precursor concentrations are systemically changed (Ni: 1.2–4.8 mol L−1; Mg: 0.3–1.2 mol L−1; Al: 0.4–1.6 mol L−1) at the optimized composition (10 wt% MgO). The effects of MgO loading and precursor concentration on the catalytic performance and resistance against poisoning of the catalyst by potassium (K) are investigated. The Ni-MgO-Al2O3 catalyst with 10 wt% MgO and the original precursor concentration (Ni: 1.2 mol L−1; Mg: 0.3 mol L−1; Al: 0.4 mol L−1) exhibits the highest CH4 conversion and resistance against K poisoning even at the extremely high gas space velocity (GHSV) of 1,512,000 h−1. Excellent SRM performance of the Ni-MgO-Al2O3 catalyst is attributed to strong metal (Ni) to alumina support interaction (SMSI) when magnesium oxide (MgO) is co-precipitated with the Ni-Al2O3. The enhanced interaction of the Ni with MgO-Al2O3 support is found to protect the active Ni species against K poisoning.

Molecular networks connected by halogen bonds have been actively studied due to their ubiquity in biological systems and complementary role to hydrogen bonds. Although networks of planar molecules with halogen ligands have been studied using scanning tunneling microscopy (STM), those of non-planar molecules have not. Here, we report on the network structures of non-planar molecules containing Br-ligands, tetrabromo-spirobifluorene on Au (111), studied using STM. One and two-dimensional networks were observed and their intermolecular interactions were investigated. In two-dimensional networks, a molecule forms 3.5 Br⋯Br halogen bonds and 2 Br⋯H hydrogen bonds, as supported by our density functional theory calculation results. Our study demonstrates that intermolecular structures of non-planar molecules with halogen bonds can be probed on surfaces using STM.

In the design of supramolecular structures, Y-shaped molecules are useful to expand the structures in three different directions. The supramolecular structures of Y-shaped molecules with three halogen-ligands on surfaces have been extensively studied, but much less are done for those with six halogen-ligands. Here, we report on the intermolecular interactions of a Y-shaped molecule, 1,3,5-Tris(3,5-dibromophenyl)benzene, with six Br-ligands studied using scanning tunneling microscopy (STM). Honeycomb-like structures were observed on Au(111), and could be explained with chiral triple-nodes made of three Br···Br halogen bonds. Molecular models were proposed based on STM images and reproduced with density-functional theory calculations. Although the molecule has six Br-ligands, only three of them form Br···Br halogen bonds because of geometrical restrictions. Our study shows that halogenated Y-shaped molecules will be useful components for building supramolecular structures.

Metal oxide (MgO, CaO, and La2O3) promoted Ni-Ce0.8Zr0.2O2 catalysts have been applied for low-temperature steam reforming of methane (SRM), and the promoter effect was investigated. The addition of the metal oxides improved the basicity which enhances the resistance coke formation and catalytic activity. Among the prepared catalysts, the Ni-La2O3-Ce0.8Zr0.2O2 catalyst exhibited high activity and stability at a very high gas hourly space velocity of 621,704 h−1. This was mainly due to high dispersion of Ni, strong basicity of La2O3, and strong interaction between Ni and La2O3.

CeO2, ZrO2, and CeO2–ZrO2 supported on MgO-promoted Ni catalysts are developed and applied to the reforming of methane with carbon dioxide. The catalysts are prepared by the one-step co-precipitation/aging method and characterized through various techniques such as X-ray diffraction, Brunauer–Emmet–Teller measurements, pore distribution, X-ray photoelectron spectroscopy, X-ray absorption near edge spectroscopy, extended X-ray absorption fine structure analysis, H2-temperature programmed reduction, H2-chemisorption, Raman analysis, thermogravimetry analysis, and pulse H2–CO2 reactions. Ni–MgO–CeO2 shows the smallest Ni particle size and the particle size decreases with increasing ZrO2 content. Ni–MgO–Ce0.6Zr0.4O2 exhibits the largest oxygen storage capacity among the prepared catalysts. The size of the Ni particles and the oxygen storage capacity are found to be the primary and secondary key factors that influence the catalytic performance, respectively. The turnover frequency is dependent on the size of the Ni particles, but the catalytic performance is affected by the number of Ni active sites, which is estimated from the reduction degree and Ni particle size. Overall, the Ni–MgO–Ce0.8Zr0.2O2 catalyst shows the best performance owing to the high reduction degree and small Ni particle size.

Quinone molecules form self-assembled structures in biological systems playing a key role in charge transport. Here, we report on the self-assembled chain structures of three quinone molecules, anthraquinone (AQ), naphthacenequinone (NQ), and pentacenequinone (PQ) on Au(111) studied using scanning tunneling microscopy. They all formed one-dimensional chain structures confined to herringbone structures of Au(111) at the low-coverage limit. The observed structures were explained with O•••H hydrogen bonds, as revealed by our density functional theory calculations.

The Ni-MgO (NM) and Ni-MgO-CeO2 (NMC) catalysts prepared by co-precipitation at different titration rates have been applied to carbon dioxide reforming of methane (CDR). The effects of titration rates on the catalytic properties and reaction behaviors of the catalyst were varied significantly depending on the CeO2 addition. The titration rate mainly influenced the physical properties, such as Ni crystallite size and Ni dispersion, in NM catalysts, but for the NMC catalysts, chemical properties, such as oxygen storage capacity, also were affected. Regarding the change of titration rates, the NM catalysts exhibited the difference of activity, but NMC catalysts showed the difference of activity as well as stability. As a result, the NMC catalyst prepared at fast titration rate achieved the highest catalytic CDR performance at 800 °C and a high gas hourly space velocity of 720,000 mL∙g−1∙L−1.

A direct internal reforming (DIR) reaction for a molten carbonate fuel cell (MCFC) is carried out using SiO 2 supported catalysts, which are known to be a highly stable in catalytic reactions. The SiO 2 supported Ni catalysts rapidly deactivate in DIR-MCFC. To elucidate the mechanism of the catalyst deactivation, various characteristic analyses (XRD, BET, H 2 -chemisorption, FT-IR, and SEM) of calcined and used catalysts are employed. The co-existence of H 2 O and K causes the formation of the non-active nickel oxide and silica hydrate resulting in the significant decrease of Ni dispersion and BET surface area.

// Won-Jun Jang 1, * , Boyeon Choi 1, * , Sang-Hoon Song 1 , Naeun Lee 1 , Dong-Joon Kim 2 , Sooyeun Lee 1 and Chul-Ho Jeong 1 1 College of Pharmacy, Keimyung University, Daegu 42601, Republic of Korea 2 China-US (Henan) Hormel Cancer Institute, Zhengzhou 450008, China * These authors have contributed equally to this work Correspondence to: Sooyeun Lee, email: sylee21@kmu.ac.kr Chul-Ho Jeong, email: chjeong75@kmu.ac.kr Keywords: resistance, erlotinib, pancreatic cancer, metabolomics, ornithine decarboxylase Received: August 06, 2017 Accepted: September 04, 2017 Published: October 06, 2017 ABSTRACT Molecular and metabolic alterations in cancer cells are one of the leading causes of acquired resistance to chemotherapeutics. In this study, we explored an experimental strategy to identify which of these alterations can induce erlotinib resistance in human pancreatic cancer. Using genetically matched erlotinib-sensitive (BxPC-3) and erlotinib-resistant (BxPC-3ER) pancreatic cancer cells, we conducted a multi-omics analysis of metabolomes and transcriptomes in these cells. Untargeted and targeted metabolomic analyses revealed significant changes in metabolic pathways involved in the regulation of polyamines, amino acids, and fatty acids. Further transcriptomic analysis identified that ornithine decarboxylase (ODC) and its major metabolite, putrescine, contribute to the acquisition of erlotinib resistance in BxPC-3ER cells. Notably, either pharmacological or genetic blockage of ODC was able to restore erlotinib sensitivity, and this could be rescued by treatment with exogenous putrescine in erlotinib-resistant BxPC-3ER cells. Moreover, using a panel of cancer cells we demonstrated that ODC expression levels in cancer cells are inversely correlated with sensitivity to chemotherapeutics. Taken together, our findings will begin to uncover mechanisms of acquired drug resistance and ultimately help to identify potential therapeutic markers in cancer.

We report an efficient and highly enantioselective hydroboration of aliphatic 1,1-disubstituted alkenes with pinacolborane using a phosphine-Cu catalyst. The method allows facile preparation of enantiomerically enriched β-chiral alkyl pinacolboronates from a range of 1,1-disubstituted alkenes with high enantioselectivity up to 99% ee. Unprecedented enantiodiscrimination between the geminal alkyl substituents was observed with functional group compatibility in the hydroboration. Furthermore, a catalyst loading as low as 1 mol % furnished the desired product without a decrease in yield or selectivity, demonstrating its efficiency in gram scale synthesis.

A facile and scalable spray pyrolysis process is applied to synthesize multi-shelled Ni-loaded yolk-shell catalysts on various supports (Al 2 O 3 , CeO 2 , ZrO 2 , and La(OH) 3 ). The prepared catalysts are applied to direct internal reforming (DIR) in a molten carbonate fuel cell (MCFC). Even on exposure to alkali hydroxide vapors, the Ni-loaded yolk-shell catalysts remain highly active for DIR-MCFCs. The Ni@Al 2 O 3 microspheres show the highest conversion (92%) of CH 4 and the best stability among the prepared Ni-loaded yolk-shell catalysts. Although the initial CH 4 conversion of the Ni@ZrO 2 microspheres is higher than that of the Ni@CeO 2 microspheres, the Ni@CeO 2 microspheres are more stable. The catalytic performance is strongly dependent on the surface area and acidity and also partly dependent on the reducibility. The acidic nature of Al 2 O 3 combined with its high surface area and yolk-shell structure enhances the adsorption of CH 4 and resistance against alkali poisoning, resulting in efficient DIR-MCFC reactions.

A tandem hydrocupration/allylation of alkenyl boronates efficiently proceeds with NHC-copper catalysts using hydrosilane and allyl phosphate as reagents. In the presence of IMes–Cu catalyst, the allylation of in situ generated Β-α-copper intermediates smoothly occurs to give homoallylic boronates in high yields, despite competitive side reaction pathways. Mono- and disubstituted alkenyl boronates were effective in the reaction with terminal allyl phosphates, but trisubstituted substrates showed limited reactivity.

The present study focused on the effect of reducibility of support oxide (CeO2, ZrO2, TiO2, and Al2O3) over the activity of cobalt-based catalysts in high temperature water-gas shift (HT-WGS) reaction. The H2 temperature programmed reduction (TPR) and CO chemisorption characterization results showed that dispersion of cobalt over the support was increased with the increase of the reducibility of the support oxide. The supported catalysts were characterized by X-ray diffraction (XRD) and N2 adsorption–desorption. The results indicated that the Co/CeO2 catalyst possesses the highest surface area and metal dispersion in the series; Co/CeO2 > Co/ZrO2 > Co/Al2O3 > Co/TiO2. The activity results showed that Co/CeO2 was the highly active among the tested catalysts in the temperature range of 350–550 °C. Moreover, the time-on-stream study revealed that the Co/CeO2 catalyst was relatively more stable than cobalt supported on ZrO2 and Al2O3 oxides. The excellent activity and stability of the Co/CeO2 catalyst were attributed to its high metal dispersion, which is found strongly dependent on the reducible nature of the support.

Pancreatic cancer is one of the most lethal types of cancer, due to difficulty in early detection and the limited efficacy of available treatments. Erlotinib is used to inhibit the epidermal growth factor receptor for the treatment of pancreatic cancer; however, erlotinib resistance is a major issue and the mechanisms underlying the development of erlotinib resistance remain unclear. To better understand the alterations in tumor metabolism by acquired resistance to erlotinib, an erlotinib-resistant pancreatic cancer cell line (HPAC-ER) was established, followed by a comparison of the metabolic characteristics between these cells and their erlotinib-sensitive parental cells (HPAC). This comparison was accomplished through mass spectrometry-based targeted metabolic profiling. Five metabolite groups (acylcarnitines, amino acids and biogenic amines, glycerophospholipids, sphingolipids and monosaccharides) were semi-quantified and compared statistically. These results revealed significant differences between the two groups of cells. A significant increase in the level of short-chain acylcarnitines and selected lysophosphatidylcholines, and a significant decrease in the level of acyl-alkyl-phosphatidylcholines and one sphingolipid, were observed in the HPAC-ER cells compared with the HPAC cells. The metabolic changes observed in the present study support the theory that there are increased metabolic demands in erlotinib-resistant cancer, reflecting the changes in acetyl-CoA-associated and choline phospholipid metabolism. These findings will aid in elucidating the changes that occur in pancreatic cancer metabolism through the acquired resistance to erlotinib, and in the identification of biomarkers for the early detection of pancreatic cancer.

Metabolomics is a powerful tool used in the description of metabolic system perturbations caused by diseases or abnormal conditions, and it usually involves qualitative and/or quantitative metabolome determination, accompanied by bioinformatics assessment. Methamphetamine is a psychostimulant with serious abuse potential and due to the absence of effective pharmacotherapy and a high recurrence potential, methamphetamine addiction is a grave issue. Moreover, its addiction mechanisms remain unclear, probably due to the lack of experimental models that reflect personal genetic variances and environmental factors determining drug addiction occurrence. The metabolic approach is only recently being used to study the metabolic effects induced by a variety of methamphetamine exposure statuses, in order to investigate metabolic disturbances related to the adverse effects and discover potential methamphetamine addiction biomarkers. To provide a critical overview of methamphetamine-associated metabolic changes revealed in recent years using the metabolomics approach, we discussed methamphetamine toxicity, applications of metabolomics in drug abuse and addiction studies, biological samples used in metabolomics, and previous studies on metabolic alterations in a variety of biological samples—including the brain, hair, serum, plasma, and urine—following methamphetamine exposure in animal studies. Metabolic alterations observed in animal brain and other biological samples after methamphetamine exposure were associated with neuronal and energy metabolism disruptions. This review highlights the significance of further metabolomics studies in the area of methamphetamine addiction research. These findings will contribute to a better understanding of metabolic changes induced by methamphetamine addiction progress and to the design of further studies targeting the discovery of methamphetamine addiction biomarkers and therapeutic targets.

An air-stable N-heterocyclic carbene-copper thiophene-2-carboxylate (CuTC) complex has been prepared for the stereoselective hydroboration of terminal alkynes using pinacolborane (HBpin) or 1,8-naphthalenediaminatoborane (HBdan). The newly synthesized complex can be directly activated by hydroboranes without a cocatalyst such as a base, and exhibits high reactivity for the hydroboration of alkynes under mild conditions. A gram-scale hydroboration of terminal phenylacetylene demonstrated the applicability of the copper complex for the preparation of alkenyl boronates.

Metabolomics is a powerful tool used to understand comprehensive changes in the metabolic response and to study the phenotype of an organism by instrumental analysis. It most commonly involves mass spectrometry followed by data mining and metabolite assignment. For the last few decades, hair has been used as a valuable analytical sample to investigate retrospective xenobiotic exposure as it provides a wider window of detection than other biological samples such as saliva, plasma, and urine. Hair contains functional metabolomes such as amino acids and lipids. Moreover, segmental analysis of hair based on its growth rate can provide information on metabolic changes over time. Therefore, it has great potential as a metabolomics sample to monitor chronic diseases, including drug addiction or abnormal conditions. In the current review, the latest applications of hair metabolomics in animal studies and clinical settings are highlighted. For this purpose, we review and discuss the characteristics of hair as a metabolomics sample, the analytical techniques employed in hair metabolomics and the consequence of hair metabolome alterations in recent studies. Through this, the value of hair as an alternative biological sample in metabolomics is highlighted.

To investigate the effect of preparation method on the CeO2-promoted Cu/γ-Al2O3 catalyst for the high-temperature water gas shift reaction over simulated waste-derived synthesis gas, Ce/Cu/γ-Al2O3, Ce-Cu/γ-Al2O3, Cu/Ce/γ-Al2O3, and Cu/γ-Al2O3 catalysts were applied to the target reaction. Among the prepared catalysts, Ce/Cu/γ-Al2O3 showed the highest activity due to its high oxygen vacancy concentration and large amount of reduced Cu species, supported by XPS, Raman, and PL analysis. Additionally, TPR results showed that the catalyst preparation method effected the transformation of bulk CuO species to highly dispersed Cu-species, which influenced the catalyst activity.

An efficient synthetic method for preparing enantioenriched secondary borylalkanes has been achieved through a copper-catalyzed regio- and enantioselective hydroallylation of alkenyl boronates and boramides employing hydrosilanes and allylic phosphates. In the presence of a copper catalyst with a chiral Walphos ligand, a range of alkenylboron compounds with an aryl, heteroaryl, or alkyl substituent produced secondary homoallylic alkylboron compounds in good yields and with high enantioselectivities up to 99% ee. The utility of the resulting alkylboronates was demonstrated in an efficient synthesis of (S)-massoialactone.

Thermodynamic equilibrium analysis of the combined steam and carbon dioxide reforming of methane (CSCRM) and side reactions was performed using total Gibbs free energy minimization. The effects of (CO2 + H2O)/CH4 ratio (0.9–2.9), CO2:H2O ratio (3:1–1:3), and temperature (500–1000 °C) on the equilibrium conversions, yields, coke yield, and H2/CO ratio were investigated. A (CO2 + H2O)/CH4 ratio greater than 1.2, a CO2:H2O ratio of 1:2.1, and a temperature of at least 850 °C are preferable reaction conditions for the synthesis gas preparation in the gas to liquid process. Simulated conditions were applied to the CSCRM reaction and the experimental data were compared with the thermodynamic equilibrium results. The thermodynamic equilibrium results were mostly consistent with the experimental data, but the reverse water gas shift reaction rapidly occurred in the real chemical reaction and under excess oxidizing agent conditions. In addition, a long-term stability test (under simulated conditions) showed that the equilibrium conversion was maintained for 500 h and that the coke formation on the used catalyst was not observed.

A comparative study between monometallic (Me−CeO 2 , Me = Zn, Cu, Fe and Co) and Ni-doped bimetallic (Me−Ni−CeO 2 ) catalysts has been performed in the high temperature water-gas shift (HT−WGS) reaction using waste derived synthesis gas. Experimental results revealed that Me−Ni−CeO 2 exhibited higher catalytic performance than simple Me−CeO 2 catalysts. Within the Me−Ni−CeO 2 series, Co−Ni−CeO 2 exhibited excellent and stable catalytic performance (CO conversion > 90%) at a very high GHSV of 143,000 h −1 . The existence of high concentration of Ce 3+ ions and oxygen vacancies on the catalyst surface were responsible for the increased WGS activity of Co−Ni−CeO 2 . In addition, Co−Ni−CeO 2 maintains a stable performance for 50 h. However, commercial Fe 2 O 3 -Cr 2 O 3 catalyst showed a steep decline from their initial CO conversion values 15–10% within 5 h.

Multishelled, Pt-loaded Ce0.75Zr0.25O2 yolk-shell microspheres were prepared by a simple spray pyrolysis process for use in the water-gas shift (WGS) reaction. The Pt-loading was optimized, obtaining highly active Pt/Ce0.75Zr0.25O2 yolk-shell nanostructures for the WGS. Of the prepared catalysts, a 2% Pt loading of the Ce0.75Zr0.25O2 yolk-shell microspheres showed the highest CO conversion. The high catalytic activity of the 2% Pt/Ce0.75Zr0.2O2 catalyst was mainly due to its easier reducibility and the maintenance of active catalytic Pt species. The Pt-loaded Ce0.75Zr0.25O2 catalyst microspheres were highly resistant to Pt sintering because of their unique yolk-shell structure. Spray pyrolysis was found to be highly efficient for the production of precious-metal-loaded, multicomponent metal oxide yolk-shell microspheres for catalytic applications.

Ce0.6Zr0.4O2 supported transition metal (Me = Ni, Cu, Co, and Mo) catalysts have been investigated to screen for the catalytic activity and selectivity for deoxygenation reaction of oleic acid. Me-Ce0.6Zr0.4O2 catalysts were prepared by a co-precipitation method. Ni-Ce0.6Zr0.4O2 catalyst exhibited much higher oleic acid conversion, selectivity for C9 to C17 compounds, and oxygen removal efficiency than the others. This is mainly ascribed to the presence of free Ni species, synergy effects between Ni and Ce0.6Zr0.4O2, and the highest BET surface area.

Preferential CO oxidation reaction has been carried out at a gas hourly space velocity of 46,129 h−1 over supported Pt catalysts prepared by an incipient wetness impregnation method. Al2O3, MgO-Al2O3 (MgO=30 wt% and 70 wt%) and MgO were employed as supports for the target reaction. 1 wt% Pt/Al2O3 catalyst exhibited very high performance (X CO >90% at 175 °C for 100 h) in the reformate gases containing CO2 under severe conditions. This result is mainly due to the highest Pt dispersion, easier reducibility of PtO x , and easier electron transfer of metallic Pt. In addition, 1 wt% Pt/Al2O3 catalyst was also tested in the reformate gases with both CO2 and H2O to evaluate under realistic condition.

A Cu-catalyzed highly Z-stereoselective hydroboration of alkynes with 1,8-naphthalenediaminatoborane (HB(dan)) is developed. DPEphos (bis[(2-diphenylphosphino)phenyl]ether)-ligated Cu catalysts produced alkenylboron compounds from terminal alkynes with excellent Z-stereoselectivity. In contrast, using a SIPr-CuCl complex as the precatalyst exclusively produced E-hydroboration products at mild conditions. Both catalytic procedures form alkenylboron products stereocomplementary to each other, constituting stereodivergent hydroboration of alkynes through Cu catalysis. Deuterium labeling and isomerization studies support the Z-selective hydroboration via trans-addition of the boron reagent to terminal alkynes as opposed to precedent noble-metal-catalyzed trans-hydroborations.

Won-Jun Jang․Yang-Byung ParkDepartment of Industrial and Management Systems Engineering, Kyung Hee UniversityThis paper proposes a mathematical model-based solution for sourcing decisions with an objective of minimiz-ing the manufacturer’s total cost in the two-echelon supply chain with supply capacity risk. The risk impact is represented by uniform, beta, and triangular distributions. For the mathematical model, the probability vector of normal, risk, and recovery statuses are developed by using the status transition probability matrix and the equa-tions for estimating the supply capacity under risk and recovery statuses are derived for each of the three probability distributions. Those formulas derived are validated using the sampling method. The results of the simulation study on the test problem show that the sourcing decisions using the proposed solution reduce the total cost by 1.6～3.7%, compared with the ones without a consideration of supply capacity risk. The total cost reduction increases approximately in a linear fashion as the probability of risk occurrence or reduction rate of supply capacity due to risk events is increased.

Selected metal ions (Ni, Co, Mn, Mg, or Zn) were introduced into iron oxide (spinel lattice) and the resulting materials screened for catalytic activity for the high temperature water–gas shift reaction using waste-derived syngas. The active phase of spinel ferrite catalysts was directly synthesized by the glycine assisted sol–gel combustion method under a reducing atmosphere. Among the prepared catalysts, NiFe 2 O 4 catalyst showed the highest CO conversion (81%) with stability even at a very high gas hourly space velocity of 40,057 h −1 . This result was primarily due to the inverse spinel structure and easier reducibility of NiFe 2 O 4 catalyst.

The novel Mn-modified ordered mesoporous Co 3 O 4 catalysts were investigated for water gas shift reaction (WGSR), which was synthesized through a nano-casting method using a hard template of KIT-6. An incipient wetness impregnation of Mn precursor with different concentrations was applied for preparing Mn-modified mesoporous Co 3 O 4 . On 15 wt%Mn impregnated mesoporous Co 3 O 4 (denoted as Mn(15)/meso-Co 3 O 4 ), WGSR activity was found to be higher among the tested catalysts due to a higher structural stability of the Co 3 O 4 mesopores with a larger surface area. The Mn(15)/meso-Co 3 O 4 also showed stable ordered mesopore structures with an exposed larger number of active metallic cobalt sites on the surfaces even after WGSR. The structural stability was mainly attributed to the strong and stable interactions between cobalt oxides and manganese oxides. With an optimum amount of Mn promoter, Mn plays an important role as a structural stabilizer of the mesoporous Co 3 O 4 as well as an electron modifier by enhancing redox cycle properties of cobalt species and fast mass transport in mesopores.

The effective cure for oral squamous cell carcinoma (OSCC) patients is challenging due late diagnosis and fatal metastasis. The standard diagnosis for OSCC often depends on the subjective interpretation of conventional histopathology. Additionally, there is no standard way for OSCC prognosis. Over the past decade, nano-mechanical stiffness has been considered as a quantitative measure for cancer diagnosis. Nevertheless, its application to OSCC diagnosis and prognosis is still in a primitive stage. In this study, we investigated whether the OSCC progression can be predicted by nano-mechanical properties in combination with biochemical properties, especially the epithelial-mesenchymal transition (EMT). Atomic force microscopy-based nano-mechanical measurements of three different OSCC cell lines-SCC-4, SCC-9, and SCC-15-were conducted together with biochemical analyses. The gradual upregulation of Snail2, N-cadherin, and vimentin and the simultaneous downregulation of E-cadherin were observed, and the degree of upregulation and downregulation was stronger in the order of the cell lines mentioned above. The strength of enhancement in migration was in the same order as well. Consistently, nano-mechanical stiffness was gradually decreased as the EMT progresses. These results suggest that the nano-mechanical assay could serve as a quantitative tool to predict the OSCC progression in the context of the EMT. Furthermore, we found that the upregulated vimentin, a major filamentous component of the cytoskeleton, may contribute to mechanical softening, which can be discerned from the role of actin filaments in mechanical stiffness. In conclusion, our combinational study proposes a novel way to elucidate the mechanism of OSCC progression and its therapeutic targets.

In this study, we report an investigation of the low temperature water–gas shift (LT-WGS) reaction over a series of non-noble metal doped (Me = Mn, Fe, Co, and Ni) mesoporous Co3O4 catalysts. The effect of metal dopants on the structure and reducibility of the mesoporous Co3O4 oxide was examined using X-ray diffraction (XRD), N2-adsorption/desorption isotherm measurements, and H2-temperature programmed reduction (TPR) measurements. Experimental results revealed that among the Me-doped Co3O4 catalysts, Ni/Co3O4 demonstrated the highest catalytic performance (XCO = 93% with 47% H2 yield at 280 °C). The higher activity of the Ni-doped Co3O4 catalyst was mainly due to its smaller crystallite size (8.6 nm) and strong interaction between Co and Ni, which lead to the higher reducibility of Co3O4 compared to the other metal-doped Co3O4. To further optimize the loading of Ni- over the mesoporous Co3O4, a series of Ni(x%)/Co3O4 catalysts were prepared by varying the Ni-loading in the range of 3 to 15 wt%. Among these catalysts, 5 wt% Ni- was found to be the optimum loading, whereas higher Ni-loaded samples (10 and 15 wt%) showed a decrease in catalytic performance and hydrogen yield during the WGS reaction.

Methamphetamine (MA) use disorder is a chronic neuropsychiatric disease characterized by recurrent binge episodes, intervals of abstinence, and relapses to MA use. Therefore, identification of the key genes and pathways involved is important for improving the diagnosis and treatment of this disorder. In this study, high-throughput RNA sequencing was performed to find the key genes and examine the comparability of gene expression between whisker follicles and the striatum of rats following MA self-administration. A total of 253 and 87 differentially expressed genes (DEGs) were identified in whisker follicles and the striatum, respectively. Multivariate and network analyses were performed on these DEGs to find hub genes and key pathways within the constructed network. A total of 129 and 49 genes were finally selected from the DEG sets of whisker follicles and of the striatum. Statistically significant DEGs were found to belong to the classes of genes involved in nicotine addiction, cocaine addiction, and amphetamine addiction in the striatum as well as in Parkinson&rsquo, s, Huntington&rsquo, s, and Alzheimer&rsquo, s diseases in whisker follicles. Of note, several genes and pathways including retrograde endocannabinoid signaling and the synaptic vesicle cycle pathway were common between the two tissues. Therefore, this study provides the first data on gene expression levels in whisker follicles and in the striatum in relation to MA reward and thereby may accelerate the research on the whisker follicle as an alternative source of biomarkers for the diagnosis of MA use disorder.

The detection and monitoring of colorless and odorless chemical warfare agents (CWAs) has become important due to the increasing threat of terrorist activities. To enhance the sensitivity and selectivity of CWAs a number of sensing materials have been developed, including the widely used polyvinylidene fluoride (PVDF). However, PVDF is limited by its low sensitivity and selectivity for many CWAs. In this study, polyhedral oligomeric silsesquioxane (POSS) was used as a sensing material for dimethyl methylphosphonate (DMMP) a simulant of sarin nerve gas. Sensitivity, selectivity, and reusability were investigated with an AT-cut 5 MHz quartz crystal microbalance. At room temperature, POSS exhibited a strong response for DMMP vapor at different concentrations from 20 ppm to 120 ppm leading to fast chemical adsorption and desorption. To investigate selectivity the volatile organic compounds (VOCs) ethanol, water, toluene, ACN, methanol, and n-hexane were tested at a fixed flow rate. Targeted VOCs showed lower responses than DMMP as measured with a quartz crystal microbalance (QCM) sensor, demonstrating the high selectivity of the method. POSS can be considered a potentially useful material for sensing nerve simulants.

The concept of drug repositioning has recently received considerable attention in the field of oncology. In the present study, we propose that paroxetine can be used as a potent anticancer drug. Paroxetine, one of the selective serotonin reuptake inhibitors (SSRIs), has been widely prescribed for the treatment of depression and anxiety disorders. Recently, SSRIs have been reported to have anticancer activity in various types of cancer cells; however, the underlying mechanisms of their action are not yet known. In this study, we investigated the potential anticancer effect of paroxetine in human colorectal cancer cells, HCT116 and HT‐29. Treatment with paroxetine reduced cell viability, which was associated with marked increase in apoptosis, in both the cell lines. Also, paroxetine effectively inhibited colony formation and 3D spheroid formation. We speculated that the mode of action of paroxetine might be through the inhibition of two major receptor tyrosine kinases – MET and ERBB3 – leading to the suppression of AKT, ERK and p38 activation and induction of JNK and caspase‐3 pathways. Moreover, in vivo experiments revealed that treatment of athymic nude mice bearing HT‐29 cells with paroxetine remarkably suppressed tumour growth. In conclusion, paroxetine is a potential therapeutic option for patients with colorectal cancer.

Cancer is the second leading cause of death worldwide and has become a global burden. It has long been known that inflammation is related to cancer, as inflammatory components have been identified in the tumor microenvironment and support tumor progression. Among the key inflammatory mediators, leukotrienes were found to be involved in cancer development. In particular, leukotriene B4, which is converted from leukotriene A4 by leukotriene A4 hydrolase (LTA4H), has been implicated in several types of cancer. In addition, LTA4H has attracted attention because of purported roles in inflammation and cancer development. Herein, we review the history of LTA4H, its emerging roles in cancer development, and the development of LTA4H inhibitors in cancer prevention and therapy.

Mitochondrial dysfunction has been found to be associated with various pathological conditions, particularly cancer. However, the mechanisms underlying tumor malignancy induced by mitochondrial dysfunction are not fully understood. In the present study, the effects of mitochondrial dysfunction on epithelial-mesenchymal transition (EMT), were investigated using mitochondrial-depleted ρ(0) cells derived from the Hep3B hepatocarcinoma cell line. The Hep3B/ρ(0) cells displayed the EMT phenotype with more aggressive migration and higher invasiveness compared to their parental cells. The Hep3B/ρ(0) cells also showed typical expression pattern of EMT markers such as vimentin and E-cadherin. These phenotypes in Hep3B/ρ(0) cells were mediated by increased transforming growth factor-β (TGF-β) through the canonical Smad-dependent signaling pathway. Additionally, TGF-β signaling was activated via induction of c-Jun/AP-1 expression and activity. Therefore, mitochondrial dysfunction induces EMT through TGF-β/Smad/Snail signaling via c-Jun/AP-1 activation. These results indicate that mitochondrial dysfunction plays an important role in the EMT process and could be a novel therapeutic target for malignant cancer therapy.

The effect of preparation method on Fe/Al/Cu oxide-based catalysts was investigated for the high temperature water gas shift reaction using simulated waste-derived synthesis gas. Impregnated Fe/Al/Cu catalyst and sol–gel prepared Fe/Al/Cu catalyst were compared with a co-precipitated Fe/Al/Cu catalyst. The co-precipitated Fe/Al/Cu catalyst exhibited very high CO conversion (XCO > 85% at 450 °C) with stable activity. This performance was attributed to the high surface area, the small crystallite size of the Fe3O4, the ease of reducibility, and formation of reduced form of the Cu species.

Theories predicted that one-dimensional superlattice potentials in graphene would induce new Dirac points, instead of gap opening, due to lattice-induced chirality of charge carriers, but experimental evidence is rarely available in the literature. Here, we report observations of new Dirac points in one-dimensionally rippled graphene on hexagonal boron nitride (h-BN) using scanning tunneling microscopy and spectroscopy. The rippled graphene, formed due to thermal procedures, showed two new Dirac points above and below the Fermi level. The energy difference between a new Dirac point and the Fermi level was proportional to 1/L, where L was the period of a ripple, in agreement with theoretical predictions. Our study shows that the one-dimensional periodic potential is an accessible component for controlling the electronic properties of graphene.

The effect of the preparation method on the activity and stability of Ni–Cu–CeO 2 oxide catalysts have been investigated in the high temperature water–gas shift (HT–WGS) reaction. The highest CO conversion (85%) and selectivity was achieved by the catalyst prepared by evaporation induced self-assembly method (Ni–Cu–CeO 2 −SG) at a very high GHSV of 84,000 h −1 . The improved performance of the catalyst was attributed to the mesoporous nature of the Ni–Cu–CeO 2 −SG which can provide higher surface area and facilitate the easier diffusion of gas through its mesoporous channels.