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CeO2 supports have been synthesized through a different precipitation/digestion method with various cerium precursors (cerium hydroxide (CH), cerium hydroxy carbonate (CHC), cerium carbonate (CC)). Nano-sized CeO2 supports with a high BET surface area were prepared through the pre-calcination of cerium precursors. 20 wt.% of Cu was loaded onto the prepared CeO2 supports through an incipient wetness impregnation method. Among the prepared catalysts, Cu/CeO2-CHC yielded the highest CO conversion between the temperature range from 200 to 360 °C. This result was primarily due to possessing the highest Cu dispersion and a high oxygen storage capacity (OSC). In addition, the 20 wt.% Cu/CeO2 catalyst exhibited 100 % CO2 selectivity.

Drug use disorder, a chronic and relapsing mental disorder, is primarily diagnosed via self-reports of drug-seeking behavioral and psychological conditions, accompanied by psychiatric assessment. Therefore, the identification of peripheral biomarkers that reflect pathological changes caused by such disorders is essential for improving treatment monitoring. Hair possesses great potential as a metabolomic sample for monitoring chronic diseases. This study aimed to investigate metabolic alterations in hair to elucidate a suitable treatment modality for methamphetamine (MA) use disorder. Consequently, both targeted and untargeted metabolomics analyses were performed via mass spectrometry on hair samples obtained from current and former patients with MA use disorder. Healthy subjects (HS), current (CP), and former (FP) patients with this disorder were selected based on psychiatric diagnosis and screening the concentrations of MA in hair. The drug abuse screening questionnaire scores did not differentiate between CP and FP. Moreover, according to both targeted and untargeted metabolomics, clustering was not observed among all three groups. Nevertheless, a model of partial least squares-discriminant analysis was established between HS and CP based on seven metabolites derived from the targeted metabolomics results. Thus, this study demonstrates the promising potential of hair metabolomes for monitoring recovery from drug use disorders in clinical practice.

Recent advances in improving the spectroscopic energy resolution in scanning tunneling microscopy (STM) have been achieved by integrating electron spin resonance (ESR) with STM. Here, we demonstrate the design and performance of a homebuilt STM capable of ESR at temperatures ranging from 1 to 10 K. The STM is incorporated with a homebuilt Joule–Thomson refrigerator and a two-axis vector magnet. Our STM design allows for the deposition of atoms and molecules directly into the cold STM, eliminating the need to extract the sample for deposition. In addition, we adopt two methods to apply radio-frequency (RF) voltages to the tunnel junction: the early design of wiring to the STM tip directly and a more recent idea to use an RF antenna. Direct comparisons of ESR results measured using the two methods and simulations of electric field distribution around the tunnel junction show that, despite their different designs and capacitive coupling to the tunnel junction, there is no discernible difference in the driving and detection of ESR. Furthermore, at a magnetic field of ∼1.6 T, we observe ESR signals (near 40 GHz) sustained up to 10 K, which is the highest temperature for ESR-STM measurement reported to date, to the best of our knowledge. Although the ESR intensity exponentially decreases with increasing temperature, our ESR-STM system with low noise at the tunnel junction allows us to measure weak ESR signals with intensities of a few fA. Our new design of an ESR-STM system, which is operational in a large frequency and temperature range, can broaden the use of ESR spectroscopy in STM and enable the simple modification of existing STM systems, which will hopefully accelerate a generalized use of ESR-STM.

Recently, efforts have been made to adapt surface acoustic waves (SAWs) for use in chemical sensors for detection of chemical warfare agents (CWAs). In this study, a four-channel real-time CWA detection system was constructed using four 250-MHz SAW sensors. Each system consists of three different chemical sensors and one reference sensor. The reference sensor compensates for frequency variations according to humidity and temperature conditions. Signals from the SAW sensors can be checked on a PC-based graphical user interface without additional measuring equipment. To measure dimethyl methylphosphonate (DMMP), a simulant of sarin gas, polyhedral oligomeric silsesquioxane (POSS) and thiourea (TU)-based synthetic polymers were used as sensing materials. The reference sensor was not coated, whereas the three different chemical sensors were coated with POSS, TU-1, and TU-2. The maximum frequencies of POSS, TU-1, and TU-2 were shifted 15.86, 13.85, and 0.944 kHz, showing significant values. We also found a relatively good linear relation between the frequency shift and the concentration of DMMP. The three sensing materials selected-POSS, TU-1, and TU-2-responded significantly to DMMP and triethylphosphate in the selectivity tests. This response is due to the chemical bonding of the sensing materials with the phosphonate in the nerve-agent simulants. These results indicate that the four-channel SAW monitoring system described in this paper shows potential as a portable real-time monitoring system to detect a variety of toxic vapors simultaneously, without using complex measuring equipment. In addition, this approach has demonstrated potential for developing excellent portable sensors to detect different types of CWAs.

Enhanced catalytic performance is required to increase the efficiency of hydrogen production from waste-derived synthesis gas via the high-temperature water-gas shift reaction (HT-WGSR). Herein, the effects of barium, zirconium, and neodymium doping on the physico-chemical properties of a Ce/Cu/Al2O3 catalyst as well as its catalytic performance for HT-WGSR are investigated. Ce/Cu/Al2O3 catalysts with various additives (barium, zirconium, and neodymium) prepared via a sequential impregnation method have been characterized by using N2 adsorption-desorption isotherms, X-ray powder diffraction (XRPD), N2O-titration, X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and hydrogen temperature-programmed reduction (H2-TPR). Advantageously, barium and zirconium addition enhance the HT-WGSR activity and stability of the Ce/Cu/Al2O3 catalyst, whereas neodymium doping has a negative effect. Regarding the correlation of catalytic performance with the characterization results, it was found that catalytic activity and stability strongly depended on their oxygen vacancy concentration and strong-metal to support interaction.

Ni-MgO catalysts have been widely applied for carbon dioxide reforming (CDR) reaction due to their ability of anti-carbon formation. However, activation of Ni-MgO catalyst consumes considerable energy because of its very low reducibility. In this study, ZrO2, CeO2, and CeO2-ZrO2 promoted Ni-MgO catalysts were prepared via a facile coprecipitation method and applied to the CDR reaction. Among the prepared catalysts, the ZrO2-promoted Ni-MgO catalyst showed the highest methane conversion. The high catalytic performance of the ZrO2-promoted Ni-MgO catalyst is mainly due to easier reducibility, high Ni dispersion, and high specific surface area.

Statins are a class of lipid‐lowering drugs that have recently been used in drug repositioning in the treatment of human cancer. However, the underlying mechanism of statin‐induced cancer cell death has not been clearly defined. In the present study, we evaluated the anticancer effect of pitavastatin on oral squamous cell carcinoma (OSCC), SCC15 and SCC4 cells and found that FOXO3a might be a direct target in pitavastatin‐induced cancer cell death. Our data revealed that pitavastatin selectively suppressed cell viability and induced intrinsic apoptosis in a FOXO3a‐dependent manner in SCC15 cells while no effect was observed in SCC4 cells. Notably, treatment with pitavastatin in SCC15 cells induced the nuclear translocation of FOXO3a via dual regulation of two upstream kinases, AMPK and Akt, resulting in the up‐regulation of PUMA, a transcriptional target gene of FOXO3a. Furthermore, our data revealed that FOXO3a‐mediated PUMA induction plays a role in pitavastatin‐induced intrinsic apoptosis in SCC15 cells. Taken together, our findings suggest that pitavastatin activates the FOXO3a/PUMA apoptotic axis by regulation of nuclear translocation of FOXO3a via Akt/FOXO3a or AMPK/FOXO3a signalling. Therefore, these findings might help to elucidate the underlying mechanism of the anticancer effects of pitavastatin on OSCC.

Autophagy is a self-degradation process in which the cytoplasmic cargoes are delivered to the lysosomes for degradation. As the cargoes are degraded/recycled, the autophagy process maintains the cellular homeostasis. Anti-cancer therapies induce apoptosis and autophagy concomitantly, and the induced autophagy normally prevents stress responses that are being induced. In such cases, the inhibition of autophagy can be a reasonable strategy to enhance the efficacy of anti-cancer therapies. However, recent studies have shown that autophagy induced by anti-cancer drugs causes cell death/apoptosis induction, indicating a controversial role of autophagy in cancer cell survival or death/apoptosis. Therefore, in the present review, we aimed to assess the signaling mechanisms involved in autophagy and cell death/apoptosis induction during anti-cancer therapies. This review summarizes the process of autophagy, autophagy flux and its blockade, and measurement and interpretation of autophagy flux. Further, it describes the signaling pathways involved in the blockade of autophagy flux and the role of signaling molecules accumulated by autophagy blockade in cell death/apoptosis in various cancer cells during anti-cancer therapies. Altogether, it implies that factors such as types of cancer, drug therapies, and characteristics of autophagy should be evaluated before targeting autophagy for cancer treatment.

The effect of Nb promotion over a Cu–CeO2 catalyst was investigated in the low-temperature water gas shift reaction. The Nb loading amount was systematically varied from 0 to 5 wt% for the Cu–Nb–CeO2 catalyst, and the 1 wt% Nb promoted Cu–Nb–CeO2 catalyst exhibited the highest catalytic performance even at extremely high GHSV of 72,152 h−1. The catalysts were characterized through various techniques such as Brunauer-Emmet-Teller measurements, X-ray diffraction, N2O-chemisorption, H2-temperature programmed reduction, X-ray photoelectron spectroscopy, and transmission electron microscopy. It was found that the superior performance of the 1 wt% Nb promoted Cu–Nb–CeO2 catalyst was due to its enhanced reducibility, high BET surface area, small metallic Cu crystallite size, and high number of oxygen vacancies.

Deoxygenation by transition-metal-based catalysts is employed to produce a biofuel from fatty acids. In this study, the citric acid/CoMo ratio of an unsupported CoMo catalyst prepared by a sol–gel method was increased from 1 to 7 to investigate its effect on the physicochemical properties and performance of the catalyst. Deoxygenation was carried out at 300 °C under solvent- and hydrogen-free conditions. The CoMo-3 catalyst (e.g., citric acid/CoMo = 3) showed the highest oleic acid conversion rate, C9–C17 hydrocarbon selectivity, oxygen removal rate, and biofuel product quality. This catalyst exhibited the best catalytic performance because it had the highest amount of active species (CoMoO4). Catalyst acidity considerably effected on the catalytic performance. Additionally, the citric acid/CoMo ratio affected the formation of single/mixed Co and Mo oxides.

The loading amount of Ba promoter in the 15 wt% Co/CeO2 catalyst system was varied from 0 wt% to 3 wt%, and the resulting catalysts were used for the high-temperature water-gas shift (HTS) reaction. The catalysts were prepared by the incipient wetness co-impregnation method and studied through various characterization techniques such as X-ray diffraction, Brunauer–Emmet–Teller measurements, CO–chemisorption, H2–temperature programmed reduction, X-ray photoelectron spectroscopy, and transmission electron microscopy. The doping of Ba as a promoter in the optimal amount (1–2 wt%) improves the reducibility of the catalyst and enhances its sintering resistance. However, the doping of an excessive amount (≥3 wt%) of the promoter lowers the reducibility of the catalyst, resulting in the instability of the active phase (Co0). Overall, the 1% BaCo/CeO2 catalyst exhibited the best performance even at a severe reaction condition (CO conc. = 38%, GHSV = 143,000 h−1) owing to the strong resistance to the sintering and high stability of the active phase.

We report the isomerisation of α,β-unsaturated diesters to thermodynamically less favourable β,γ-unsaturated carbonyl compounds in the absence of strongly basic anhydrous or photochemical conditions. Stereoselective deconjugative isomerisation provides E-selective β,γ-unsaturated diesters via an enolate intermediate generated in situ from α,β-unsaturated diesters with high yield and stereoselectivity. Based on density functional theory calculations, the origin of the E-selective deconjugation pathway from conjugated compounds has been elucidated.

Asymmetric construction of C(sp3)–C(sp3) bond with good stereocontrol of the two connecting carbon centres retaining all carbon or hydrogen substituents is a challenging target in transition metal catalysis. Transition metal-catalysed reductive coupling of unsaturated π-substrates is considered as a potent tool to expediently develop the molecular complexity with high atom efficiency. However, such an asymmetric and intermolecular process has yet to be developed fully. Herein, we report an efficient strategy to reductively couple two prochiral conjugate alkenes using a copper-catalysed tandem protocol in the presence of diboron. Notably, this transformation incorporates a wide range of terminal and internal enynes as coupling partners and facilitates highly diastereo- and enantioselective synthesis of organoboron derivatives with multiple adjacent stereocentres in a single operation.

Histone deacetylase 6 (HDAC6) is a promising target for cancer treatment because it regulates cell mobility, protein trafficking, cell growth, apoptosis, and metastasis. However, the mechanism of HDAC6-induced anticancer drug resistance is unclear. In this study, we evaluated the anticancer effect of ACY-241, an HDAC6-selective inhibitor, on erlotinib-resistant pancreatic cancer cells that overexpress HDAC6. Our data revealed that ACY-241 hyperacetylated the HDAC6 substrate, α-tubulin, leading to a significant reduction in cell viability of erlotinib-resistant pancreatic cells, BxPC3-ER and HPAC-ER. Notably, a synergistic anticancer effect was observed in cells that received combined treatment with ACY-241 and erlotinib. Combined treatment effectively induced autophagy and inhibited autophagy through siLC3B, and siATG5 alleviated ACY-241-mediated cell death, as reflected by the recovery of PARP cleavage and apoptosis rates. In addition, combined ACY-241 and erlotinib treatment induced autophagy and subsequently, cell death by reducing AKT-mTOR activity and increasing phospho-AMPK signaling. Therefore, HDAC6 may be involved in the suppression of autophagy and acquisition of resistance to erlotinib in ER pancreatic cancer cells. ACY-241 to overcome erlotinib resistance could be an effective therapeutic strategy against pancreatic cancer.

To investigate the effect of precipitation on physico-chemical and catalytic properties of Cu-Zn-Al catalyst, the pH value and injection rate in the precipitation process were systematically changed, and the water-gas shift reaction was carried out. The Cu-Zn-Al catalyst showed the highest CO conversion when the optimized synthesis parameters (i.e., pH=10-10.5 and injection rate=30 ml/min) were employed. This is mainly due to the enhanced physicochemical properties such as a high Brunauer-Emmett-Teller surface area, small crystallite size, high Cu dispersion, and easier reducibility.

Herein, we have prepared a series of Cr-free Fe-Al-Cu catalysts by the homogeneous one-step co-precipitation method and examined their ability to promote the water gas shift (WGS) reaction and thus facilitate the production of hydrogen from waste-derived synthesis gas. The prepared catalysts are confirmed to possess γ-Fe2O3, which can be more easily transformed into Fe3O4 than α-Fe2O3. The surface area, Fe3O4 crystallite size, reducibility, and Cu dispersion of these catalysts significantly depend on the concentrations of metal precursor. The catalysts effectively promote the WGS reaction without facilitating undesirable side reactions, achieving efficient hydrogen production and high CO conversion. The characteristics of the best-performing sample are preserved when the production is scaled up by a factor of 40 and thus obtained large-scale Fe-Al-Cu catalyst exhibits excellent reducibility and high CO conversion. Both commercial Fe-Cr and large-scale Fe-Al-Cu catalysts achieve close-to-equilibrium CO conversions at a gas hourly space velocity (GHSV) of 3000 mL g−1 h−1, but the latter showed a higher conversion than the former at a GHSV of 40,057 mL g−1 h−1 owing to the promotional effect of Cu on the easier reducibility of Fe species and the formation of additional Cu active sites. Thus, we demonstrate the possibility of finding Cr-free alternatives and show that the reducibility, Fe3O4 crystallite size, and Cu dispersion of the best-performing catalyst could be maintained upon upscaling, which made this catalyst well suited for converting waste-derived synthesis gas into H2.

Herein, we investigated the effects of aging time and temperature on the performance of co-precipitation–prepared Cu-Zn-Al catalysts in the low-temperature water-gas shift (LT-WGS) reaction. The highest CO conversion within the employed temperature range as well as very stable activity over 200 h were observed for the catalyst prepared at 80 °C and aged for 72 h, which was ascribed to its high surface area and close-to-100% degree of CuO reduction. Conversely, catalysts aged at temperatures below 80 °C had poor physical properties, while aging for

We report a copper-catalyzed enantioselective hydroboration of α,β-unsaturated aldehydes with pinacolborane. α,β-Unsaturated aldehydes were converted to the corresponding γ-pinacolboronate alcohols in good yields and enantioselectivities through consecutive hydroboration of the C═O and C═C bonds. This process provides simple access to the hydroborated product of allylic alcohols, and the resulting γ-pinacolboronate alcohols could be utilized in various transformations.

To investigate the effect of support materials on catalytic performance in carbon dioxide reforming of coke oven gas, Ni-based catalysts supported on various metal oxides with various properties are prepared and evaluated. The support material affects the important properties related to the catalytic performance such as surface area, Ni dispersion, basicity, oxygen storage capacity, and interaction between Ni and support. Among the various catalysts on different metal oxides, Ni/MgO Al2O3 catalyst exhibits the highest CH4 conversion due to its high Ni dispersion, large surface area, and strong basicity. Hence, the Ni loading in the Ni/MgO Al2O3 catalyst is optimized. Ni loading performs the important roles to determine the Ni dispersion, the amount of Ni active sites, and basicity. 15 wt% Ni/MgO Al2O3 catalyst shows the highest catalytic activity even at a high gas hourly space velocity (GHSV) of 1,500,000 h−1, owing to the large amount of Ni active sites which related to Ni loading, Ni dispersion, and reduction degree. To confirm the stability of the 15 wt% Ni/MgO Al2O3 catalyst, catalytic reaction has been carried out for 50 h and noticeable catalytic deactivation is not observed for 50 h.

Because the whole world is under threat from climate change, 195 countries decided to reduce greenhouse gas (GHG) emissions by adopting the “Paris Agreement”. The mitigation and utilization of GHG have become the most significant challenges in the area of green energy research. One feasible solution is the reforming of methane with carbon dioxide (called dry reforming of methane, DRM) that converts the two main GHGs (CO2 and CH4) into synthesis gas (H2 and CO), which is a resource for the manufacture of useful value-added products. The main issue that needs to be addressed for DRM is the deactivation of catalysts by sintering and carbon formation. Design of a viable catalyst that exhibits high catalytic activity and stability, as well as resistance against deactivation, could be accomplished by making appropriate choices of active metal, support, promoter, structure and methods for preparation and activation. Numerous studies and reviews have dealt with various aspects of DRM. This review focuses on the physicochemical properties of the pertinent catalysts and their role in the catalytic performance needed for DRM. Specifically, the interaction between components, dispersion, particle size, basicity, oxygen storage capacity, reducibility, porosity and surface area are discussed. This study provides the understanding of catalytic properties and their correlation with catalytic performance needed for the rational design of catalysts and suitable for DRM.

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.

We investigated spin-1/2 hydrogenated titanium (Ti) atoms on MgO using scanning tunneling microscopy (STM) combined with electron spin resonance (ESR) in vector magnetic fields. Rotating external magnetic fields, we observed rather drastic changes in both amplitude and frequency of resonance signals for single Ti atoms. While the variation of ESR amplitudes reflects the effects of the spin polarization of a magnetic tip and local magnetic fields created by the interaction between the tip and Ti, the change of resonance frequencies shows the anisotropy of g values for Ti atoms. Using the Ti atoms at the low-symmetry bridge adsorption site of the MgO lattice allowed for identifying the g values in all three spatial directions. Multiplet calculations confirmed the origin of this anisotropy as the spin-orbit coupling induced effects of crystal. Our results show the capability of single atomic spins as a sensor to probe magnetic surroundings and highlight the precision of ESR-STM to identify the single atom's spin states in a solid-state environment., This work was supported by the Institute for Basic Science (Grant No. IBS-R027-D1). D.-J.C. acknowledges financial support from the Spanish MICINN (Project No. RTI2018- 097895-B-C44 and Excelencia Project No. EUR2020-112116) and Eusko Jaurlaritza (Project No. PIBA_2020_-1_0017). F.D. acknowledges financial support from Spanish MICINN (Grant No. PID2019-109539GB-C41), Basque Government (Grant No. IT986-16), and Canary Islands program Viera y Clavijo (Grant No. 2017/0000231). C.P.L. acknowledges financial support from the ONR.

Ni/MgO-Al2O3 (Ni/MG70) catalysts were developed for the deoxygenation reaction to produce green diesel from non-edible fatty acids. As the Ni loading amount was increased from 5% to 30%, the characteristics of the catalysts, such as Brunauer–Emmett–Teller (BET) surface area, Ni dispersion, reducibility, number of Ni active sites, and acidity, varied. Among the prepared catalysts, the 20% Ni/MG70 catalyst showed excellent deoxygenation performance owing to its highest number of Ni active sites, easier reducibility, and appropriate acidity. Furthermore, it was confirmed that deoxygenation in this study was carried out via the hydrodeoxygenation reaction pathway to remove oxygen species as H2O. In addition, the basic fuel properties, calorific value and viscosity, were analyzed for produced green diesel.

We report the diastereo- and enantioselective conjugate addition of chiral secondary borylalkyl copper species derived from borylalkenes in situ to α,β-unsaturated diesters. In the presence of a chiral bisphosphine-ligated CuH catalyst, the conjugate addition provides a direct access to enantioenriched alkylboron compounds containing two contiguous carbon stereogenic centers in good yield with high diastereo- and enantioselectivity (up to >98:2 dr, >99:1 er) by assembling readily available starting alkenyl reagents in a single operation without using preformed organometallic reagents or chiral auxiliaries. The resulting products were used in various organic transformations. The utility of the synthetic approach was highlighted by the synthesis of (-)-phaseolinic acid.

Methamphetamine (MA) is a highly addictive central nervous system stimulant. Drug addiction is not a static condition but rather a chronically relapsing disorder. Hair is a valuable and stable specimen for chronic toxicological monitoring as it retains toxicants and metabolites. The primary focus of this study was to discover the metabolic effects encompassing diverse pathological symptoms of MA addiction. Therefore, metabolic alterations were investigated in human hair following heavy MA abuse using both targeted and untargeted mass spectrometry and through integrated network analysis. The statistical analyses (t-test, variable importance on projection score, and receiver-operator characteristic curve) demonstrated that 32 metabolites (in targeted metabolomics) as well as 417 and 224 ion features (in positive and negative ionization modes of untargeted metabolomics, respectively) were critically dysregulated. The network analysis showed that the biosynthesis or metabolism of lipids, such as glycosphingolipids, sphingolipids, glycerophospholipids, and ether lipids, as well as the metabolism of amino acids (glycine, serine and threonine, cysteine and methionine) is affected by heavy MA abuse. These findings reveal crucial metabolic effects caused by MA addiction, with emphasis on the value of human hair as a diagnostic specimen for determining drug addiction, and will aid in identifying robust diagnostic markers and therapeutic targets.