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This work introduces, for the first time, the energy harvesting performance of conjugated microporous polymers (CMPs) as tribo-positive materials for triboelectric nanogenerators (TENGs). Various nano or submicron CMP particles (CMP-X) were prepared by the Sonogashira coupling of 1,3,5-triethynylbenzene with 1,4-diiodoarenes. Optimized CMP-X nanoparticles in a polyurethane (PU) matrix showed excellent triboelectrification performance, displaying peak-to-peak voltages of up to 411 V and a maximum power density of 0.80 mW cm−2. Moreover, an optimized 5.0% CMP-H@PU-based TENG could be utilized as a power source for the charging of an electrolytic capacitor and for the operation of 100 LEDs.

Transition-metal phosphide (TMP) nanostructures have been extensively studied for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). However, phase-controlled synthesis of collo...

The development of nanostructured architectures using low-cost first–row transition metals with high electrocatalytic activity to replace noble-metal-based electrocatalysts has recently gained considerable attention in the field of clean and sustainable energy generation technology. In this study, highly efficient, binder-free, Ni–Co layered double hydroxide (NiCo-LDH) nanowires on a nickel foam (NF) substrate were fabricated via a simple, one-step hydrothermal synthesis procedure, and their use as electrocatalysts for the oxygen evolution reaction (OER) and methanol oxidation reaction (MOR) was studied. When NiCo-LDH was used as the OER electrocatalyst, the overpotential required to deliver a current density of 20 and 100 mA cm−2, was only 270 and 410 mV (without iR correction), and it exhibited a long-term stability of 50 h in 1 M KOH. Moreover, the as-prepared NiCo-LDH nanowire electrocatalyst presented remarkable electrochemical performance for the MOR with a higher current density of 761 mA cm−2 at 0.7 V vs. the saturated calomel electrode (SCE) and excellent stability in 1 M KOH with 0.5 M methanol. The vertically aligned NiCo-LDH nanowires presented numerous active sites and open structures and their synergism with the highly conductive NF substrate was responsible for the excellent electrochemical performance of the electrocatalyst.

In recent years, low-cost, non-noble metal-based and stable catalysts have gained attention for the development of clean energy devices. Additionally, the synthesis of materials that can exhibit more than one electrocatalytic reaction is notable. In this work, stepwise electrodeposited nickel-iron hydroxide nanoarrays are investigated as anode electrocatalysts with enhanced performance towards the oxidation of water, urea, and hydrazine. The stepwise electrodeposited nickel-iron hydroxide (NiFe(OH)2-SD/NF) electrodes show excellent electrocatalytic activity and stability for the oxygen evolution reaction (OER) with a low potential of 1.45 V (vs RHE) at a current density of 10 mA cm−2. These electrodes further display excellent catalytic activity towards the urea oxidation reaction (UOR) and hydrazine oxidation reaction (HzOR) with potentials lower than 1.32 V (vs RHE) and 0.06 V (vs RHE), respectively. Owing to synergistic effects, a porous structure for mass transport leads to excellent electrocatalytic performance. This non-precious-metal nickel-iron hydroxide, prepared by a simple synthesis approach, is promising for hybrid water electrolysis applications and the development of environmentally friendly clean energy reactions.

Cyclooxygenase-2 is overexpressed in all stages of cancers and thus serves as an attractive biomarker for early cancer diagnosis. In this study, we report a two-photon probe (SCX) for cyclooxygenase-2 which can reflect the intracellular enzyme level and distinguish between cancerous and normal tissue in colorectal cancer patients. SCX is based on a novel two-photon fluorophore (PBT) possessing phenanthrene donor and benzothiazole acceptor, and indomethacin as a COX-2 targeting unit. The in vitro and cell imaging studies revealed that SCX could distinguish the COX-2 expression levels in cancerous and normal cells. Furthermore, for the first time, normal and cancerous tissues could clearly be distinguished in human biopsy samples by using a COX-2 responsible two-photon probe.

Gambogic acid (GA), a xanthonoid extracted from the resin of the tree, Garcinia hanburyi, was recently shown to exert anticancer activity in multiple studies, but the underlying action mechanism remains unclear. Here, we show that GA induces cancer cell death accompanied by vacuolation in vitro and in vivo. This GA-induced vacuolation in various cancer cells was derived from dilation of the endoplasmic reticulum (ER) and mitochondria, and was blocked by cycloheximide. These findings suggest that GA kills cancer cells by inducing paraptosis, a vacuolization-associated cell death. We found that megamitochondria formation, which arose from the fusion of swollen mitochondria, preceded the fusion of ER-derived vacuoles. GA-induced proteasomal inhibition was found to contribute to the ER dilation and ER stress seen in treated cancer cells, and megamitochondria formation was followed by mitochondrial membrane depolarization. Interestingly, GA-induced paraptosis was effectively blocked by various thiol-containing antioxidants, and this effect was independent of ROS generation. We observed that GA can react with cysteinyl thiol to form Michael adducts, suggesting that the ability of GA to covalently modify the nucleophilic cysteinyl groups of proteins may cause protein misfolding and subsequent accumulation of misfolded proteins within the ER and mitochondria. Collectively, our findings show that disruption of thiol proteostasis and subsequent paraptosis may critically contribute to the anti-cancer effects of GA.

Elevated Bcl-xL expression in cancer cells contributes to doxorubicin (DOX) resistance, leading to failure in chemotherapy. In addition, the clinical use of high-dose doxorubicin (DOX) in cancer therapy has been limited by issues with cardiotoxicity and hepatotoxicity. Here, we show that co-treatment with pyrrolidine dithiocarbamate (PDTC) attenuates DOX-induced apoptosis in Chang-L liver cells and human hepatocytes, but overcomes DOX resistance in Bcl-xL-overexpressing Chang-L cells and several hepatocellular carcinoma (HCC) cell lines with high Bcl-xL expression. Additionally, combined treatment with DOX and PDTC markedly retarded tumor growth in a Huh-7 HCC cell xenograft tumor model, compared to either mono-treatment. These results suggest that DOX/PDTC co-treatment may provide a safe and effective therapeutic strategy against malignant hepatoma cells with Bcl-xL-mediated apoptotic defects. We also found that induction of paraptosis, a cell death mode that is accompanied by dilation of the endoplasmic reticulum and mitochondria, is involved in this anti-cancer effect of DOX/PDTC. The intracellular glutathione levels were reduced in Bcl-xL-overexpressing Chang-L cells treated with DOX/PDTC, and DOX/PDTC-induced paraptosis was effectively blocked by pretreatment with thiol-antioxidants, but not by non-thiol antioxidants. Collectively, our results suggest that disruption of thiol homeostasis may critically contribute to DOX/PDTC-induced paraptosis in Bcl-xL-overexpressing cells.

>> Activated charcoal supported nickel molybdenum carbide (carburized Ni-Mo/AC) catalysts were prepared by wet-impregnation followed by temperature-programmed carburization using 20% CH 4 /H 2 gas. The effects of pH and initial Ni/Mo mole ratio during wet-impregnation step on the characteristics of the carburizedNi-Mo/AC catalysts were investigated using ICP, XRD, XPS, BET and CO 2 -TPD techniques, and correlated withthe catalytic activity of the carburized Ni-Mo/AC in methane dry reforming reaction. Comparison of the resultsof methane dry reforming reaction kinetics with the results of characterization of the carburized Ni-Mo/AC catalystshowed that the catalytic activity in methane dry reforming reaction was higher at higher initial Ni/Mo mole ratioor at lower pH(3~natural value). This phenomenon was related to the crystal size of metallic Ni in the carburizedNi-Mo/AC catalyst. Key words : Nickel molybdenum carbide(니켈 몰리브덴 카바이드), Wet-impregnation(습식담지), Carburization(침탄), pH(수소이온농도지수), Initial Ni/Mo mole ratio(초기 Ni/Mo 몰비)

The proteasome inhibitor (PI), bortezomib (Btz), is effective in treating multiple myeloma and mantle cell lymphoma, but not solid tumors. In this study, we show for the first time that lercanidipine (Ler), an antihypertensive drug, enhances the cytotoxicity of various PIs, including Btz, carfilzomib, and ixazomib, in many solid tumor cell lines by inducing paraptosis, which is accompanied by severe vacuolation derived from the endoplasmic reticulum (ER) and mitochondria. We found that Ler potentiates Btz-mediated ER stress and ER dilation, possibly due to misfolded protein accumulation, in MDA-MB 435S cells. In addition, the combination of Btz and Ler triggers mitochondrial Ca2+ overload, critically contributing to mitochondrial dilation and subsequent paraptotic events, including mitochondrial membrane potential loss and ER dilation. Taken together, our results suggest that a combined regimen of PI and Ler may effectively kill cancer cells via structural and functional perturbations of the ER and mitochondria.

Since mobile source is a major source of VOCs, quantifying emissions from motor vehicles is an important factor to control VOCs in atmosphere. In this study, in order to evaluate tailpipe VOCs emissions from motor vehicles, mass emissions of non-methane volatile organic compounds from 45 vehicles were determined. Measurements were made on a chassis dynamometer using CVS-75 mode and speed specific drive modes. Target VOCs are 53 compounds determined as the volatile ozone precursors. The individual VOCs composition of vehicle emission and emission rates were also determined. In case of gasoline vehicles, VOCs emission from over 80,000 km vehicles were about 46% larger than less 80,000 km vehicles. The difference in benzene and toluene according to driving mileage was 44% and 26% respectively. The composition of VOCs were different by fuel type. The order of VOCs composition was paraffins>aromatics>olefins in gasoline vehicle emissions, paraffins>olefins>aromatics in light duty diesel vehicle emissions. The VOCs emissions were decreased as vehicle speed increasing. These results will be used to calculate total VOCs emissions from automobiles in the future.

Regio- and stereoselective radical addition of α-allenic alcohols with p-TsBr in the presence of a catalytic amount of AIBN afforded (E)-γ-bromo-β-sulfonyl allylic alcohols in moderate yields. The base-promoted 1,4-elimination followed by isomerization to give β-sulfonyl-α,β-unsaturated ketones is described.

The proteasome inhibitor, bortezomib, is ineffective against many solid tumors. Nutlin-3 is a potent antagonist of human homolog of murine double minute 2/p53 interaction exhibiting promising therapeutic anti-cancer activity. In this study, we show that treatment of various p53-defective bortezomib-resistant solid tumor cells with bortezomib plus nutlin-3 induces paraptosis, which is a cell death mode accompanied by dilation of the endoplasmic reticulum (ER) and mitochondria. Bortezomib alone did not markedly alter cellular morphology, and nutlin-3 alone induced only a transient mitochondrial dilation. However, bortezomib/nutlin-3 co-treatment triggered the progressive fusion of swollen ER and the formation of megamitochondria, leading to cell death. Mechanistically, proteasomal-impairment-induced ER stress, CHOP upregulation and disruption of Ca2+ homeostasis were found to be critically involved in the bortezomib/nutlin-3-induced dilation of the ER. Our results further suggest that mitochondrial unfolded protein stress may play an important role in the mitochondrial dilation observed during bortezomib/nutlin-3-induced cell death. Collectively, these findings suggest that bortezomib/nutlin-3 perturbs proteostasis, triggering ER/mitochondria stress and irrecoverable impairments in their structure and function, ultimately leading to paraptotic cell death.

To examine the independent effect of metabolic syndrome (MS) on nephrolithiasis (NL) even with changes in MS status over time.From 2002-2003, 3872 men who were reexamined annually or biannually until 2009 were enrolled in the analysis and observed for development of NL. The examination included anthropometric measurements, biochemical measurement, and kidney ultrasonography (US). A standard Cox proportional hazards model and a time-dependent Cox model were used to calculate the adjusted hazard ratio in the NL model.After adjusting for age, baseline glomerular filtration rate, and uric acid level, MS at baseline was associated with a significantly increased risk of NL (HR, 1.771; 95% confidence interval, 1.157-2.711). MS over time as a time-dependent variable also predicted the development of NL (HR, 1.678; 95% CI, 1.151-2.447) after adjusted baseline covariate. After adjustment for potential confounding factors, there was a significant stepwise increase in risk of NL, with each additional MS trait compared with those with no traits of MS at baseline and follow-up. As the numbers of MS traits at baseline and follow-up increased, the urine pH of participants at baseline and follow-up decreased significantly (P.01). The prevalence of NL in participants with continual MS (6.6%) was higher than those with resolved MS, and continual MS was an independent factor to predict NL.Our findings suggest that MS is significantly associated with increased risk of developing urine acidification, even with changes in status of MS observed during follow-up.

Asthma is a chronic inflammatory disease of the airways characterized by reversible airway obstruction, airway hyperreactivity, and remodeling of the airways. Chlorogenic acid (CGA), an ester of caffeic acid with quinic acid, is one of the most abundant polyphenol compounds in various agricultural products. CGA shows various biological properties, such as anti-oxidant, anti-viral, anti-carcinogenic and anti-inflammatory activities. We investigated suppressive effects of CGA on ovalbumin (OVA)-induced allergic asthma in mice and underlying mechanisms of them. CGA significantly reduced pulmonary eosinophilia and expression of IL-4, IL-5 and TNF-α in the lung as well as the serum levels of total and OVA-specific IgE, while CGA enhanced those of total and OVA-specific IgG3, of which isotype switching is down-regulated by IL-4. In vitro IgE production from LPS/IL-4-stimulated splenocytes was remarkably reduced by CGA, while that of IgG3 was enhanced. The Ce germ line transcription, which is necessary for IL-4 mediated IgE isotype switching, was reduced by CGA in LPS/IL-4-stimulated splenocytes. IgE isotype switching is mediated via several transduction pathways, activating several molecules including STAT-6, NF-κB, ERK1/2, and JNK. Among the molecules, which were activated by IL-4/LPS, activation of STAT-6 and JNK was inhibited by CGA.

Although use of carbohydrates to install the required stereocenters is a rela-tively effective strategy, better, more efficient, and unified syn-thetic pathways to these ophiocerins could be devised if starting materials other than carbohydrates, with set stereochemical cen-ters, were utilized. Since carbohydrate-based approaches must include the destruction or conversion of unnecessary or incorrect stereocenters, more direct synthetic routes were sought out in which ophiocerins could be secured by creating the required stereochemistry after synthesizing the tetrahydropyran ring.The general synthetic strategy presented herein is shown in the following retrosynthetic analysis (Scheme 1). The ophio-cerins could be derived from dihydropyran derivative

We also reported a carbohydrate-based approach to the total synthesis of ophiocerin C (3). The commercially available methyl α-D-glucopyranoside (5) was converted to the key intermediate 6, which was then transformed to the target compound 3. The successful synthesis of ophiocerin C led us to investigate the total synthesis of other ophiocerins. We, herein, report the synthesis of ophiocerin A (1) and B (2).

This study examined the optical and electrical properties of indium tin oxide (ITO) films treated with a hydrogen plasma and a post-HCl solution. ITO films, 200 nm in thickness, were deposited on polyethylene terephthalate (PET) substrates by the radio frequency magnetron sputtering method. The samples were then exposed to an inductively coupled hydrogen plasma and this was followed by HCl : DI solution treatment. The work function of the ITO surface was decreased from 4.94 to 4.61 eV without thermal annealing. The sheet resistance was decreased due to the formation of a high density of O–H bonds and oxygen vacancies. Although the transmittance of the hydrogen-plasma-treated sample was decreased drastically by the formation of In/Sn clusters, enhanced transmittance and increased optical band gap without a deterioration of the electrical properties could be achieved effectively by removing the In/Sn clusters using a HCl solution.