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In this study, free-standing PIL/IL composite membranes of 1-bromohexyl-1 methylpiperidinium bromide (Br-6-MPRD) grafted poly(2,6 dimethyl 1,4 phenylene oxide) (ILPPO) incorporated with different amounts of free Br-6-MPRD (0, 2, 5 and 10 wt%) were prepared and the effect of free ionic liquid on CO2, N2 and O2 transport properties were reported. The structure of piperidinium based polyionic liquid (PIL) synthesised was confirmed using nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR) spectral techniques. Gas permeation results at 1 bar pressure and 25 °C revealed the best CO2 permeability and CO2/N2 as well as CO2/O2 permselectivities of the membrane stretch to 907.20 Barrer (higher than Pebax® 1657), 12.94 and 14.90 respectively for ILPPO/Br-6-MPRD-2 which come within reach of the 2008 Robeson limit. Apart from most of the published works, ILPPO/Br-6-MPRD-2 membrane revealed an anti-trade-off permeability-selectivity performances which is most required and a great challenge for CO2 separation and capture applications.

In this study, the medium requirements to increase the production of xylitol by using Candida tropicalis (CT) have been investigated. The technique of single addition or omission of medium components was applied to determine the nutritional requirements. The addition of amino acids such as Asp, Glu, Gln, Asn, Thr, and Gly had no significant effect on CT growth. However, in the absence of other metal ions, there was a higher concentration of cell growth and xylitol production when only Zn(2+) was present in the medium. The analysis of various vitamins unveiled that biotin and thiamine were the only vitamins required for the growth of CT. Surprisingly, when only biotin was present in the medium as a vitamin, there was less growth of CT than when the medium was complete, but the amount of xylitol released was significantly higher. Overall, this study will increase the xylitol production using the single omission or addtion technique.

Anion exchange membranes (AEMs) with good alkaline stability and ion conductivity are fabricated by incorporating quaternary ammonium-modified silica into quaternary ammonium-functionalized poly(2,6-dimethyl-1,4-phenylene oxide) (QPPO). Quaternary ammonium with a long alkyl chain is chemically grafted to the silica in situ during synthesis. Glycidyltrimethylammoniumchloride functionalization on silica (QSiO2) is characterized by Fourier transform infrared and transmission electron microscopic techniques. The QPPO/QSiO2 membrane having an ion exchange capacity of 3.21 meq·g–1 exhibits the maximum hydration number (λ = 11.15) and highest hydroxide ion conductivity of 45.08 × 10–2 S cm–1 at 80 °C. In addition to the high ion conductivity, AEMs also exhibit good alkaline stability, and the conductivity retention of the QPPO/QSiO2-3 membrane after 1200 h of exposure in 1 M potassium hydroxide at room temperature is about 91% ascribed to the steric hindrance offered by the grafted long glycidyl trimethylammonium chain in QSiO2. The application of the QPPO/QSiO2-3 membrane to an alkaline fuel cell can yield a peak power density of 142 mW cm–2 at a current density of 323 mA cm–2 and 0.44 V, which is higher than those of commercially available FAA-3-50 Fumatech AEM (OCV: 0.91 V; maximum power density: 114 mW cm–2 at current density: 266 mA cm–2 and 0.43 V). These membranes provide valuable insights on future directions for advanced AEM development for fuel cells.

1-Nitropyrene (1-NP) is a major nitro-polycyclic aromatic hydrocarbon (nitro-PAH), and a common constituent in diesel exhaust particles (DEPs). Absorbed 1-nitropyrene is partly metabolized to 1-aminopyrene and excreted in urine. Recently, the number of diesel cars has been increasing, which could be a major cause of air pollution, resulting elevated levels of traffic-related DEPs around cities. The aim of this study was to investigate the usability of 1-aminopyrene (1-AP) as a biomarker for DEP exposure by examining the association between urinary 1-AP concentration and the amount of exposure to atmospheric 1-NP. The study subjects included 65 individuals who work on vehicular roads or bus terminals. Their 24 h urine samples were collected, and atmospheric air was sampled using a personal air sampler for 24 h. Urinary 1-AP and atmospheric nitro-PAH levels were measured using a high-pressure liquid chromatography-fluorescence detector (HPLC-FD). The average urine 1-AP concentration was 0.334 pg/g creatinine. Urinary 1-AP levels were significantly correlated with 1-NP level exposure (r = 0.385, p = 0.002) but not with the other nitro-PAHs. When the subjects were classified into high-and low-exposure groups, a significant association was only found in the high exposure group (r = 0.357, p = 0.045). In conclusion, there was a significant correlation between 1-NP exposure and urinary 1-AP concentration; therefore, urinary 1-AP level could be used as an exposure biomarker for DEP. Supplementary Information The online version contains supplementary material available at 10.1007/s43188-021-00096-z.

In fuel cell and electrolysis systems, hydrogen crossover is a phenomenon where hydrogen molecules (H2) permeate through a membrane, lowering the overall process efficiency and generating a potential safety risk. Many works have been reported to mitigate this undesired phenomenon, but it is yet difficult to accurately measure the rate of hydrogen crossover, particularly when the membrane is fully wetted in water. In this work, we investigated the pressure decay method as a simple, convenient, and low-cost method to characterize hydrogen crossover through wetted membranes for water electrolysis systems. Three different ion exchange membranes were analyzed: Nafion 212, Nafion 115, and in-house sulfonated poly(arylene ether sulfone). We rigorously confirmed our method and data by comparing it to the ANSI dataset with the current state-of-the-art equations of state (EOS) to account for the nonideality of high pressure hydrogen systems. The error from the gas non-ideality was less than 0.03%. As expected, the rate of hydrogen crossover showed high dependency on the temperature; more importantly, hydrogen crossover increased significantly when the membrane was fully soaked in water. For dry membranes, the proposed pressure decay method corroborated well with the literature data measured using other known methods. Moreover, for wetted membranes, the obtained data showed high similarity compared to the GC method which is currently the most reliable method in the literature. We attempted to predict the hydrogen permeability of wetted membranes using the solution diffusion model. The model based on the given thermodynamic parameters overestimated the hydrogen permeability, which can be used to estimate the ion channel tortuosity.

Among the various cathode materials used in LIBs (Lithium ion batteries), nickel rich cathode materials have attracted an increasing amount of interest due to their high capacity, relatively low cost, and low toxicity when compared to LiCoO2. However, these materials always contain a large amount of residual lithium compounds such as LiOH and Li2CO3. The presence of lithium residues is undesirable because the oxidation of these compounds results in the formation of Li2O and CO2 gas at higher voltages, which lowers the coulombic efficiency between the charge and discharge capacities during cycling. In this study, using LiNi0.8Co0.1Mn0.1O2 as a starting material, a surface-modified cathode material was obtained by using reducing agent. The reducing agent not only plays the role of reducing the oxide conversion energy but also suppresses the side reaction with the electrolyte due to the surface modification. Residual lithium present on the cathode material surface was reduced from 11,702 ppm to 8,658 ppm, resulting in improved high temperature cycle performance and impedance characteristics.

People living near abandoned mines are at increased risk of exposure to toxic metals. We surveyed 4500 inhabitants with the mean age of 68.5 years old (male: 1768, female: 2732) living near 104 abandoned metal mines from 2013 to 2017 (the 2nd phase health survey in Korea). We conducted personal interviews, blood and urine sampling, and analyzed the concentrations of lead (Pb) and cadmium (Cd) in whole blood and Cd in urine using a graphite furnace atomic absorption spectrometer. The geometric means of blood Pb, blood Cd, and urine Cd were 2.27 μg/dL, 1.42 μg/L, and 1.66 μg/g creatinine, respectively. The level of metal exposure was lower than that reported from the first phase health survey in Korea (2008‒2011) but was higher than in the general population of Korea. Blood Pb was higher in males while blood Cd and urine Cd were significantly higher in females. Blood Pb was highest in the 40‒59 age group, while blood and urine Cd levels continuously increased until age 80 or older. The Cd levels in blood and urine were affected by consumption of locally produced rice and duration of residence near abandoned mines. Furthermore, negative correlations were observed between blood Pb and blood and urine Cd levels. Additionally, 252 of the 4500 subjects exceeded the thresholds of blood Cd or urine Cd levels. Together, these findings suggest that Cd has more sustainable and adverse health effects on the abandoned mine inhabitants, who are mostly aged. Therefore, continuous biomonitoring and risk assessment to environmental health risks are necessary for environmental pollution control and health promotion.

The process of crosslinking is widely employed to increase the physicochemical stability of anion exchange membranes and, in some cases, improve ion conductivity. For a general case in which a polymer is crosslinked by a crosslinking agent, the physicochemical properties of the polymer can be greatly altered, depending on the type of crosslinking agent. In this study, we induced crosslinking without a crosslinking agent to intentionally maximise various physical properties (i.e., mechanical properties, swelling ratios, and so forth) of two commercially-available polymers. A triazole was incorporated into the conducting group to maximise the ion conductivity, especially under room humidity (RH) conditions. The crosslinked PPO-SEBS membranes prepared through this approach were not only capable of forming very thin membranes (10 μm thickness) with excellent physical properties (34.3 MPa of tensile strength and 91.6% of elongation at break) but also exhibited high hydroxide ion conductivity under 95% RH, and conductivity plays an important role in achieving good fuel cell performance. When the membrane electrode assembly (MEA), as fabricated utilising a crosslinked PPO-SEBS membrane and a platinum on carbon (Pt/C) catalyst on each electrode, was operated in conditions with a H2/O2 gas flow and a 60 °C temperature, a stable fuel cell performance was obtained for a long period of time (300 hours) at a maximum power density of 405 mW cm−2. This result surpasses the performance of commercialized AEMs and is comparable with the performance levels of cutting-edge AEMs when operated under similar conditions.

In the present study, Rhus vernicifera laccase (RvLac) was immobilized through covalent methods on the magnetic nanoparticles. Fe(2)O(3) and Fe(3)O(4) nanoparticles activated by 3-aminopropyltriethoxysilane followed with glutaraldehyde showed maximum immobilization yields and relative activity up to 81.4 and 84.3% at optimum incubation and pH of 18 h and 5.8, respectively. The maximum RvLac loading of 156 mg/g of support was recorded on Fe(2)O(3) nanoparticles. A higher optimum pH and temperature of 4.0 and 45 °C were noted for immobilized enzyme compared to values of 3.5 and 40 °C for free form, respectively. Immobilized RvLac exhibited better relative activity profiles at various pH and temperature ranges. The immobilized enzyme showed up to 16-fold improvement in the thermal stability, when incubated at 60 °C, and retained up to 82.9% of residual activity after ten cycles of reuses. Immobilized RvLac exhibited up to 1.9-fold higher bisphenol A degradation efficiency potential over free enzyme. Previous reports have demonstrated the immobilization of RvLac on non-magnetic supports. This study has demonstrated that immobilization of RvLac on magnetic nanoparticles is very efficient especially for achieving high loading, better pH and temperature profiles, and thermal- and solvents-stability, high reusability, and higher degradation of bisphenol A.

This study investigated the optimum temperature and holding solutions for the storage of cut flowers of Arenaria juncea M. Bieb. to facilitate their introduction as a new ornamental plant. We examined the effects of different holding solutions on the water uptake, vase life, and fresh weight of five branches of A. juncea. After harvest, cut branches were stored at 4, 15, 20, and 25°C. To study the effect of the holding solutions, the cut branches were treated with a combination of sucrose (1% and 3%), 8-hydroxyqunoline sulfate (8-HQS: 10, 50, and 100 mg·L-1), and commercial preservative solutions Chrysal and Floralife. At a storage temperature of 4°C, the vase life was 29 days, which was significantly longer compared to room temperature, where the vase life was 7.8 days. Thus, a lower temperature was more effective at extending the vase life. A combination of 1% sucrose and 100 mg·L-1 8-HQS prolonged the vase life by approximately two weeks compared to the control. The effect of both Chrysal and Floralife was similar to the effect of the holding solutions composed of sucrose and 8-HQS. Moreover, rapid reduction of water uptake and fresh weight resulted in a shorter vase life.

In this study, PEEKs with different contents of imidazolium group (DI-PEEK) were synthesized by facile condensation polymerization using bisphenol A, 2,2′-di(2-ethyl-methylimidazole-methylene)-4,4′-dihydroxydiphenylether and difluorobenzophenone. Highly flexible and transparent DI-PEEK membranes showing anion exchange behavior could be prepared by the DI-PEEK solution using DMAc as a solvent. The DI-PEEK membrane with optimized content of imidazolium group (30 mol%) showed the highest ion conductivity (78 mS/cm at 80 ℃) without deterioration of thermal and mechanical stability among the samples. A membrane electrode assembly using the DI-PEEK membrane with optimized content of imidazolium group revealed comparable cell performance (98 mW/cm2 at 0.43 V) to that using a commercialized anion exchane membrane (114 mW/cm2 at 0.43 V) under operating conditions of 60 ℃ and 100% RH.

The prickly pear cactus (Opuntia), native to Mexico, has grown in popularity and is locally grown and adapted on Jeju Island. The fruits of this cactus species are in particular widely employed as raw materials, which are then processed into various food and medicinal items, including chocolates and vitamins, for purposes of human consumption. Because this crop has been dubbed one of Jeju’s iconic agricultural crops, research studies elucidating the prickly pear cactus’ medicinal properties, including antioxidant activity, of this particular plant and related cultivated species have demonstrated high value to the scientific community. Currently, consumers do not purchase products f or c onsumption a lone, but in a ddition f or t heir added health benef its. The present study in particular honed in on two species of prickly pear cactus that are cultivated on Jeju Island which include: ‘Baeknyeoncho’ (Opuntia ficus-indica) and ‘Cheonnyeoncho’ (Opuntia humifusa). From these species, s pecif ci p lant p arts i ncluding t he f lower, mature and y oung stems, roots, a nd f ruit w ere subjected to further antioxidant analysis, which included the determination of polyphenol, flavonoid, DPPH radical, ABTS radical, and anthocyanin levels. These particular antioxidants were determined during two seasons, over the course of the summer and winter. Results revealed that the antioxidant activity for both species was more active during the summer season. Antioxidant levels occurred at the highest rates within t he flowers o f the c actus plants. However, of significant note was that the cactus stem, in both mature and young plants, possessed higher antioxidant activity compared to those of the fruit that is currently employed for commercial purposes.

We chemically modify a commercially available elastomeric triblock copolymer, poly(styrene-b-ethylene-co-butylene-b-styrene) SEBS, to produce quaternary ammonium-functionalized hexyl bis(quaternary ammonium)-mediated partially-crosslinked SEBSs with different grafting degree of the conducting head groups as highly conductive and stable anion exchange membranes (AEMs). In an attempt to achieve a high ion exchange capacity and hence conductivity of the corresponding membranes without causing ‘gelation’, which these types of SEBS polymers typically experience, we use a SEBS with a high content (57%) of styrene, and graft the quaternary ammonium (QA) as both a crosslinker and the conducting head group on the side chain of the SEBS. The partial crosslinking approach, in combination with introducing these QA-conducting head groups as the side chain of the SEBS, helps to form larger ion clusters, and also to form a nano-phase morphology with long-range connecting channels. This induced the highest ion conductivity, 174.8 mS cm−1 at 80 °C, reported to date among these types of SEBS series. In addition, we obtain excellent cell performance with a current density of 450 mA cm−2 at 0.6 V and a peak power density of 315 mW cm−2 at 95% RH and 60 °C using the corresponding AEM.

Despite the many advances that have been made in using anionic surfactants to disperse and sort single-walled carbon nanotubes (SWNTs) for optoelectronic applications, one-pot methods for deposition of SWNTs in a diameter (dt) and position controlled manner from as-dispersed sample are essential. Here, we designed and prepared flavin-containing self-assembled monolayers (flavin-SAMs) that can be used to assemble dt-selective individualized SWNT networks directly from SWNT dispersions by using the widely-used anionic surfactant. For a given glass substrate, the dimethallylsilane-linked azide, along with surface immobilization was employed to have Click reaction with terminal acetylene tethered to flavin group known to have strong affinity with SWNT. As demonstrated by atomic force microscopy and other methods, along successful assembly of individualized networks, the SWNTs are either fully or partially wrapped in a dt selective manner by isoalloxazine moieties tethered to the surface, displaying Langmuir isotherm adsorption behaviors in a dipping method dependent manner. The assembled SWNT network secures photoluminescence and electrical conductivity albeit its intimacy to underlying substrate and near monolayer coverage of SWNT network, respectively, and, furthermore, preferentially takes place on flavin-SAM over hydrophobic surface.

Photosynthetic bacteria, Rhodobacter spharoides, can grow using carbon dioxide as a carbon source and produce physiologically active compounds. This study was carried out to investigate the impact of R. sphaeroides extract on the growth and quality of lettuce(Lactuca sativa L.) in the LED-plant factory. The concentrations of R. sphaeroides extracts(0, 4, 8 and 12 mg/L) were supplemented in medium on one day and 14 days after transplanting, respectively. The growth of lettuce as affected by extract amount was evaluated at 14, 28 and 35 days after transplanting and the contents of minerals and chlorogenic acid were analyzed at 35 days after transplanting. As a result, higher growth was obtained in the treatment with R. sphaeroides extract than the control. The extract of R. sphaeroides showed the best growth at 4 mg/L concentration(leaf width- 120%, leaf length- 109%, number of leaves- 113%, total leaf area- 144%, fresh weight- top: 153%, root: 142%, dry weight- top: 137%, root: 120%) and the highest effect at the early stage of growth on 14 days after transplanting(leaf width- 115%, leaf length- 123%, number of leaves- 124%, total leaf area- 158%, fresh weight- top: 139%, root: 120%, dry weight- top: 130%, root: 139%). In addition, the extract of 4 mg/L concentration improved the content of minerals and chlorogenic acid contained in lettuce. Therefore, R. sphaeroides extract suggested the possibility of producing high-value crops through promotion of growth and quality improvement of lettuce.

CD73 inhibitors are promising drugs for the (immuno)therapy of cancer. Here, we present the synthesis, structure-activity relationships, and cocrystal structures of novel derivatives of the competitive CD73 inhibitor α,β-methylene-ADP (AOPCP) substituted in the 2-position. Small polar or lipophilic residues increased potency, 2-iodo- and 2-chloro-adenosine-5'-O-[(phosphonomethyl)phosphonic acid] (15, 16) being the most potent inhibitors with Ki values toward human CD73 of 3-6 nM. Subject to the size and nature of the 2-substituent, variable binding modes were observed by X-ray crystallography. Depending on the binding mode, large species differences were found, e.g., 2-piperazinyl-AOPCP (21) was >12-fold less potent against rat CD73 compared to human CD73. This study shows that high CD73 inhibitory potency can be achieved by simply introducing a small substituent into the 2-position of AOPCP without the necessity of additional bulky N6-substituents. Moreover, it provides valuable insights into the binding modes of competitive CD73 inhibitors, representing an excellent basis for drug development.

This study is to assess the hydrogeochemical characteristics of groundwater at the deltaic region of the Nakdong River Basin in the Busan Metropolitan City of Korea. The study area is covered by the Quaternary sedimentary deposits and the Cretaceous granites associated with unconformity. The thick sedimentary deposits consists of two aquifers, i.e., unconfined and confined aquifers on the basis of clay deposit. Groundwater samples were collected from seven boreholes: two from unconfined aquifer and five from confined aquifer systems during the wet season of 2017 year. ORP and DO indicates that the groundwater of the unconfined aquifer exists in the oxidization condition and that of the confined aquifer pertains in the reduction condition. Piper’s trilinear diagram shows CaSO4 type for groundwater of the unconfined aquifer, and NaCl type for that of the confined aquifer. Ionic concentrations of groundwater increase in the confined aquifer because of direct and reverse ion exchange processes. Carbonate weathering and evaporation are other mechanisms in the water-rock interaction. Saturation indices of dolomite and calcite are observed as oversaturated, while halite reveals undersaturation. Hierarchical cluster analysis (HCA) exhibits that cluster 1 and cluster 2 represents the properties of groundwater in unconfined and confined aquifers, respectively. Factor analysis shows that groundwater of the confined aquifer is much influenced by seawater, and includes heavy metals of iron and aluminum. Groundwater samples in unconfined and confined aquifers are located at the rock weathering and evaporation zones in the Gibbs diagram. Inverse geochemical modeling of PHREEQC code suggests that carbonate dissolution and ion exchange of major ions are the prevailing geochemical processes. This comprehensive research provides the distinguished hydrogeochemical characteristics of groundwater in confined and unconfined aquifer systems of the Nakdong River Basin in Busan City, Korea.

Methods: First, the experiment was conducted on a lab-scale, treated with 1%, 2%, 5% and 10% extracts in manure, followed by reaction for 3 days. The concentrations of NH3, H2S and CH3SH were measured using a gas detector. A scale-up odor reduction experiment was then conducted in a swine house. Finally, the odor reduction effect was compared with the commercial product (M-product) for evaluation. Results: As a result of comparing the ammonia gas reduction with respect to the concentration of the yeast-derived extract, it was confirmed that the reduction of ammonia was improved depending on the treated concentration in both samples of Yeast-W and Yeast-SS. The concentration of NH3, H2S, and CH3SH from swine house showed significant differences between that of manure from the control and extract treatment group, with Yeast-SS showing the highest efficacy. The reduction rate of Yeast-SS 1% treatment on NH3 was 46.7%, which appeared similar to that of 2% treatment of M-product. Also, the reduction rate of Yeast 2% treatment reached a maximum of 53.4%, which showed a high efficiency for the reduction of NH3. Conclusion: Yeast-SS is an effective odor removal agent even at low concentrations compared with other odor reducing agents, with potential applicability as an environmental improvement agent for managing odorous gas of swine manure.

Purpose This cross-sectional study aimed to assess the effect of environmental cadmium (Cd) exposure and essential metal imbalance on renal tubular damage and oxidative stress in 979 adults living in a Cd-polluted area near an abandoned copper (Cu) refinery. Methods We analyzed urinary Cd concentrations, renal tubular damage and oxidative stress markers, such as beta-2 microglobulin (β2-MG) and N-acetyl-β-d-glucosaminidase (NAG) activity and urine malondialdehyde (MDA) levels. The serum copper-to-zinc ratio (CZR) was used as an essential metal imbalance indicator. We divided the subjects into two Cd exposure groups based on the reference level of urinary Cd for renal dysfunction (2 μg/g creatinine). Results The geometric mean concentration of urinary Cd in all subjects was 2.25 μg/g creatinine. In both low and high Cd exposure groups, urinary Cd levels were positively correlated with urinary NAG activity, but not with serum CZR. After multivariate adjustment, serum CZR was strongly associated with urinary β2-MG levels in the low Cd exposure group (β = 1.360, P = 0.019) and was significantly associated with urinary MDA levels, regardless of Cd exposure level. In addition, the risk of renal tubular damage was significantly associated with urinary Cd level, particularly in the lowest or highest CZR tertile groups. Conclusions Essential metal imbalance may be a determinant of oxidative stress and renal tubular damage in a chronically Cd-exposed population, and proper zinc supplementation will be effective in preventing adverse health effects due to Cd exposure.

A Gram-stain-negative, facultatively anaerobic, motile, light-yellow, and rod-shaped bacterium, designated as NY-02T, was isolated from the sludge of a wastewater treatment plant in Hanam City, Republic of Korea. The comparison of 16S rRNA gene sequences revealed that the strain formed a distinct lineage within the genus Simplicispira and was most closely related to S. suum SC1-8T (99.0%), S. limi EMB325T (98.3%), S. psychrophila LMG 5408T (98.2%), and S. piscis RSG39T (97.4%). Both average nucleotide identity (ANI) and DNA–DNA hybridization (DDH) values between strain NY-02T, and its closes type strains [S. suum SC1-8T, S. limi EMB325T, S. psychrophila LMG 5408T, and S. piscis RSG39T] were lower than the cut-off (≥ 95–96% for ANI and ≥ 70% for DDH) to define a bacterial species. The genome comprises of 3,709,074 bp with a G + C content of 64.2 mol%. Ubiquinone 8 (Q-8) was the predominant quinone. The major fatty acids were C16:0 and summed feature 3 (C16:1ω7c and/or C16:1ω6c), and the major polar lipids were phosphatidylglycerol, diphosphatidylglycerol, and phosphatidylethanolamine. The results of the physiological, biochemical, and taxonomic analyses in addition to low ANI and DNA-DNA relatedness values (82.2% and

Background Euphorbia jolkinii Boiss. is a perennial species native to Jeju Island and the southern coastal area of Korea. Particularly on Jeju Island, the yellow flowers of E. jolkinii Boiss. have a high ornamental value because of their contrast with basalt. This study was conducted to investigate the effects of different temperatures (5, 15, 20, and 25 °C) and gibberellic acid (GA3) concentrations (0, 10, 100, or 1000 mg/L) on seed dormancy and germination of E. jolkinii. In addition, we classified the seed dormancy type and compared types with those of other species in the same genus. Results The number of seeds with viable embryos and endosperms was approximately 66%. The final germination percentages at 5, 15, 20, and 25 °C were 51.7%, 83.5%, 2.6%, and 0.0%, respectively. In GA3 concentration experiments, the final germination percentages of 0, 10, 100, and 1000 mg/L were 83.5%, 91.7%, 79.1%, and 83.4%, respectively, at 15 °C conditions, and 0.0%, 6.9%, 13.2%, and 27.3%, respectively, at 25 °C. Conclusions Germination improved at temperatures of 15 °C or lower. Furthermore, GA3 treatment effectively reduced germination times. Thus, the seeds of E. jolkinni were classified as having non-deep physiological dormancy.

The antithrombotic prodrugs ticlopidine and clopidogrel are thienotetrahydro-pyridine derivatives that are metabolized in the liver to produce thiols that irreversibly block adenosine diphosphate (ADP)-activated P2Y12 receptors on thrombocytes. In their native, nonmetabolized form, both drugs were reported to act as inhibitors of ectonucleoside triphosphate diphosphohydrolase-1 (NTPDase1, CD39). CD39 catalyzes the extracellular hydrolysis of nucleoside tri- and diphosphates, mainly adenosine 5'-triphosphate (ATP) and ADP, yielding adenosine monophosphate, which is further hydrolyzed by ecto-5'-nucleotidase (CD73) to produce adenosine. While ATP has proinflammatory effects, adenosine is a potent anti-inflammatory, immunosuppressive agent. Inhibitors of CD39 and CD73 have potential as novel checkpoint inhibitors for the immunotherapy of cancer and infection. In the present study, we investigated 2-substituted thienotetrahydropyridine derivatives, structurally related to ticlopidine, as CD39 inhibitors. Due to their substituent on the 2-position, they will not be metabolically transformed into reactive thiols and can, therefore, be expected to be devoid of P2Y12 receptor-antagonistic activity in vivo. Several of the investigated 2-substituted thienotetrahydropyridine derivatives showed concentration-dependent inhibition of CD39. The most potent derivative, 32, showed similar CD39-inhibitory potency to ticlopidine, both acting as allosteric inhibitors. Compound 32 showed an improved selectivity profile: While ticlopidine blocked several NTPDase isoenzymes, 32 was characterized as a novel dual inhibitor of CD39 and CD73.

In this study, blended anion exchange membranes were prepared using polyphenylene oxide containing quaternary ammonium groups and polyvinylidene fluoride. A polyvinylidene fluoride with high hydrophobicity was blended in to lower the vanadium ion permeability, which increased when the hydrophilicity increased. At the same time, the dimensional stability also improved due to the excellent physical properties of polyvinylidene fluoride. Subsequently, permeation of the vanadium ions was prevented due to the positive charge of the anion exchange membrane, and thus the permeability was relatively lower than that of a commercial proton exchange membrane. Due to the above properties, the self-discharge of the blended anion exchange membrane (30.1 h for QA–PPO/PVDF(2/8)) was also lower than that of the commercial proton exchange membrane (27.9 h for Nafion), and it was confirmed that it was an applicable candidate for vanadium redox flow batteries.

Optimization and miniaturization of existing electronic devices require the development of advanced nanostructured materials with high phase and structural purity. Over the past decade, barium titanate (BaTiO3) has attracted considerable attention due to its outstanding ferroelectric and dielectric properties. The present study involved the investigation of the phase transition and structural stability of tetragonal BaTiO3 nanopowders with pseudo-cubic phase using an in-situ high resolution and high temperature X-ray diffraction method. Under ambient conditions, the coexistence the tetragonal and cubic phases with weight fractions of 75.7% and 24.3%, respectively, was determined in BaTiO3. In the temperature range of 25 °C-300 °C, phase boundaries of BaTiO3 (180 nm in size) exhibiting several phases were detected. The phase transformation behavior, relative crystal phase content, lattice parameters, crystallite size, and tetragonality of the BaTiO3 nanopowders were established by the Rietveld refinement method at the onset temperature from 25 °C to 300 °C. Up to 150 °C, the nanopowders exhibited a complete transition of the cubic phase. Additionally, a complete tetragonal to cubic transformation was accomplished by a decrease of tetragonality at 125 °C and an increase in the crystallite size at 300 °C.

Preharvest sprouting (PHS) is a key global issue in production and end-use quality of cereals, particularly in regions where the rainfall season overlaps the harvest. To investigate transcriptomic changes in genes affected by PHS-induction and ABA-treatment, RNA-seq analysis was performed in two wheat cultivars that differ in PHS tolerance. A total of 123 unigenes related to hormone metabolism and signaling for abscisic acid (ABA), gibberellic acid (GA), indole-3-acetic acid (IAA), and cytokinin were identified and 1862 of differentially expressed genes were identified and divided into 8 groups by transcriptomic analysis. DEG analysis showed the majority of genes were categorized in sugar related processes, which interact with ABA signaling in PHS tolerant cultivar under PHS-induction. Thus, genes related to ABA are key regulators of dormancy and germination. Our results give insight into global changes in expression of plant hormone related genes in response to PHS.

BACKGROUND/AIM The mechanism responsible for B-cell translocation gene 1 (BTG1) down-regulation in breast carcinoma remains unknown. We examined the BTG1 expression status in breast carcinoma cells and investigated the mechanism underlying the observed alterations. MATERIALS AND METHODS Four breast carcinoma cell lines (SK-BR-3, MDA-MB-231, T-47D, and MCF-7), and one normal mammary epithelial cell line (MCF-10A) were analyzed. BTG1 expression was examined using quantitative reverse transcription polymerase chain reaction (PCR) and western blot. Methylation status of the BTG1 promoter was analyzed using methylation-specific PCR (MSP). To investigate the effect of methylation on BTG1, the cells were treated with a demethylating agent. RESULTS The carcinoma cells expressed significantly lower levels of BTG1 mRNA and protein than normal cells. The BTG1 promoter was highly methylated in the carcinoma cells. 5-aza-2-deoxycytidine significantly restored BTG1 expression. CONCLUSION Down-regulation of BTG1 expression through epigenetic repression is involved in mammary carcinogenesis. BTG1 is a potential diagnostic marker and therapeutic target for breast carcinoma.

Succulents are ornamental plants that are popularly used in landscaping and as potted plants. Miniatureplants that are planted in miniature pots for small spaces or tables, or in elaborateaccessories such as key chains, key holders or hanging pots, have recently become more popular. Their unique characteristics and aesthetic appeal have increased their demand especially for those species that do not grow extensively during transport or for special cases in which they are placed into tiny containers to be used in key chains. This study investigated the effects of the plant growth inhibitors chlormequat, paclobutrazol, and daminozide, on two Echeveria species, Echeveria ‘A Grimme One’ and Echeveria ‘Little Rose’. Results revealed that the plant growth inhibitors successfully controlled the growth of Echeveria species at specific concentrations. Among the inhibitors applied to the succulents, paclobutrazol at 100 ppm was found to be the most effective treatment for both the species.

Few studies have reported how temperature influences growth and development of succulents, including anthocyanin production, which could fetch better prices in the market, and understanding the factors influencing such pigments would benefit farmers. The present study investigated the effect of temperature (10°C, 20°C, and 30°C) on the growth, development, and anthocyanin concentrations in Echeveria agavoides and E. marcus. In E. agavoides, similar growth performance was observed at 10°C and 20°C based on plant height and diameter. However, subjecting the species to a high temperature of 30°C resulted in a decrease in plant height. In E. marcus, optimal growth performance was observed at 20°C. Different temperatures did not significantly affect succulent quality and color hues. Only L* values were significantly different among the Hunter’s Lab values. Similar results were observed following anthocyanin and image analyses, both of which were not significantly affected by temperature. However, an intense red pigment was observed at 20°C compared with the green pigment observed at 10°C and 30°C based on the image analysis. The results suggest that temperature influences growth, development, and anthocyanin content of Echeveria succulents, and 20°C could be the optimal temperature for the cultivation of the species.

A Gram-stain-negative, facultatively anaerobic, non-motile and rod-shaped bacterial strain, designated THG-SD5.5T, was isolated from a soil sample collected in a tangerine field, Republic of Korea. According to the 16S rRNA gene sequence comparisons, the isolate was identified as a member of the genus Chitinophaga and to be closely related to Chitinophaga ginsengihumi KACC 17604T (97.9%) and Chitinophaga rupis KACC 14521T (97.5%). The 16S rRNA gene sequence similarities with other species of the genus Chitinophaga were in the range 92.8–95.5%. Catalase test was positive. Oxidase test was negative. The DNA G + C content was determined to be 46.1 mol%. DNA-DNA hybridization values between strain THG-SD5.5T and C. ginsengihumi KACC 17604T and C. rupis KACC 14521T were 45.1% and 15.6%, respectively. Strain THG-SD5.5T was also found to be able to grow at 24–33 °C, at 0–5% NaCl and at pH 5.5–9.0. The major fatty acids were identified as anteiso-C15:0, C16:0, anteiso-C17:0 and C18:0. The dominant respiratory quinone was identified as menaquinone-7 (MK-7). The polar lipids were found to be diphosphatidylglycerol, phosphatidylethanolamine, phosphatidylglycerol, an unidentified aminolipid, two unidentified phospholipids and three unidentified lipids. Based on these phenotypic, genotypic and phylogenetic characterisations, strain THG-SD5.5T (= KACC 19338T = CGMCC 1.16304T) is concluded to represent a novel species of the genus Chitinophaga, for which the name Chitinophaga aurantiaca sp. nov. is proposed.

The development of novel methods to detect mercury is of paramount importance owing to the impact of this metal on human health and the environment. We observed that flavin mononucleotide (FMN) and its helical assembly with a single-walled carbon nanotube (SWNT) selectively bind Hg2+ arising from HgCl2 and MeHgCl. Absorption spectroscopic studies show that FMN preferentially forms a 2:1 rather than a 1:1 complex with Hg2+ at high FMN concentrations. On the basis of the analogy to the thymine–Hg–thymine complex, it is proposed that the 2:1 complex between FMN and Hg2+ comprises a Hg-bridged pair of FMN groups, regardless of the presence of SWNT. Upon addition of as little as a few hundred nanomoles of Hg2+, both FMN and FMN–SWNT exhibit absorption and photoluminescence (PL) changes. Moreover, FMN–SWNT displays simultaneous multiple sigmoidal changes in PL of SWNT tubes having different chiral vectors. Assessment of binding affinities using the Hill equation suggests that 2:1 and 1:1 complexes form between ...

Anion exchange membranes (AEMs) play prominent role in addressing alkaline fuel cell efficiency and cost. Great deal of efforts has been made in the past, particularly during the last couple of years to reach AEMs with high hydroxide conductivity, good chemical/thermal/mechanical stability, fuel cross-over resistance and low cost. The purpose of this review is to summarize and discuss the progress on the development of different AEMs for alkaline fuel cells over the last three years. The alternative AEMs based on the modified synthetic and sustainable polymers, organic/inorganic hybrid materials and additives are reviewed in the context of AEM materials.

Advanced cancer has been shown to be associated with a higher percentage of epigenetic changes than with genetic mutations. Preclinical models have shown that the combination of paclitaxel, sorafenib, and radiation therapy (RT) plays a crucial role in renal cell carcinoma (RCC) and breast cancer. This study aimed to investigate the involvement of mitochondrial cytochrome c-dependent apoptosis in the mechanism of action of a combination of paclitaxel, sorafenib, and RT in RCC and breast cancer. RCC and breast cancer cell lines were exposed to paclitaxel and sorafenib alone or combined in the presence of radiation, and cell viability was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The synergistic anticancer effects of the combination therapy on cell cycle and intracellular signaling pathways were estimated using flow cytometry and immunoblot analysis. RCC and breast cancer cell line xenograft models were used to examine the antitumor activity in vivo. Our results suggest that paclitaxel, sorafenib, and RT synergistically decreased the viability of RCC and breast cancer cells and significantly induced their apoptosis, as shown by caspase-3 cleavage. Paclitaxel, sorafenib, and radiation cotreatment reduced antiapoptotic factor levels in these cells and, thereby, significantly reduced the tumor volume of RCC and breast cancer cell xenografts. The current study suggests that paclitaxel, sorafenib, and radiation cotreatment was more effective than cotreatment with paclitaxel or sorafenib and radiation. These findings may offer a new therapeutic approach to RCC and breast cancer.

We report a non-covalent loading of ginsenoside compound K (CK) onto our previously reported gold nanoparticles (DCY51T-AuCKNps) through one-pot biosynthesis using a probiotic Lactobacillus kimchic...

Understanding the heterojunction of a lateral heterostructured transition metal dichalcogenide (hTMD) is important in order to take advantage of the combined optoelectronic properties of individual TMDs for various applications but, however, is hampered by mingled effects from lattice mismatch and substrate interaction. Here, we systematically investigated the strain occurring at lateral hTMDs consisting of molybdenum disulfide (MoS2) and molybdenum diselenide (MoSe2) prepared by chemical vapor deposition. Comparison of homologous TMDs and hTMDs from controlled growth order revealed systematic change in photoluminescence behavior depending on substrate interaction and relative lattice mismatch. Near the heterojunction, a TMD with a larger lattice constant (a) exhibits photoluminescence (PL) red-shift, whereas a TMD with smaller a shows an opposite trend owing to lattice-induced strain. These effects are augmented in a subtractive or additive manner by tensile strain from the substrate interaction. Moreove...

Nucleotide pyrophosphatase/phosphodiesterase-1 (NPP1) inhibitors have been suggested as a potential treatment for calcium pyrophosphate dihydrate (CPPD) deposition disease. Here, we targeted the development of improved NPP1 inhibitors based on acyclic mimics of Pα,α-phosphorodithioate-substituted adenine nucleotides, 7-10. The latter were obtained in a facile two-step synthesis from adenine-(methoxy)ethanol. Among analogs 7-10, adenine-(methoxy)ethoxy-Pα,α-dithio-triphosphate, 8, was the most potent NPP1 inhibitor both with purified enzyme (IC50 0.645 μM) and in osteoarthritic human chondrocytes (IC50 0.033 μM). Furthermore, it efficaciously (10-fold vs. control) inhibited ATP-induced CPPD in human articular chondrocytes. Importantly, 8 was a highly selective NPP1 inhibitor which showed only minor inhibition of NPP3, CD39 and CD73, and did not inhibit TNAP (tissue nonspecific alkaline phosphatase) activity in human chondrocytes. Furthermore, 8 did not activate P2Y1,2,6 receptors. Analog 8 was not toxic to cultured chondrocytes at 100 μM. Therefore, 8 may be suitable for further development as a drug candidate for the treatment of CPPD arthritis and other NPP1-related diseases.

Water channel formation of non-perfluorinated proton exchange membranes (PEMs) under a low humidifying condition is a very important issue, due to weaker phase separation between hydrophilic and hydrophobic moieties than in the case of perfluorinated PEMs such as Nafion. In this study, we performed Molecular dynamics (MD) simulations of hydrated sulfonated polyimide (SPI) models, one of the representative non-perfluorinated PEMs, under different temperature and humidifying conditions by removing water molecules continuously, reflecting experimental conditions of actual low humidifying fuel cell. The water channel morphology of sulfonated polyimide (SPI) models had no apparent temperature dependence. The hydrated SPI models show weak water channel formation even in a fully hydrated condition (λ = 16.4), consistent with our previous study, and they do not display significant temperature dependence on the water molecule distribution. As the λ value decreases from 16.4 to 2 (i.e., low humidifying conditions), the water molecules in the hydrated SPI models are evenly reduced. In particular, when the λ value of the hydrated SPI model decreases from 8.5 to 6, the size of the water clusters is significantly narrowed and the clusters become segregated, and this is also confirmed by an X-ray scattering analysis. As a result, the proton conducting performance of hydrated SPI models shows similar behavior with the change in water channel morphologies, which will be very important to design a novel non-perfluorinated hydrocarbon PEM with high performance for practical fuel cell systems.

Uroplakin (UP) tetraspanins and their associated proteins are major mammalian urothelial differentiation products that form unique two-dimensional crystals of 16-nm particles (“urothelial plaques”) covering the apical urothelial surface. Although uroplakins are highly expressed only in mammalian urothelium and are often referred to as being urothelium specific, they are also expressed in several mouse nonurothelial cell types in stomach, kidney, prostate, epididymis, testis/sperms, and ovary/oocytes. In oocytes, uroplakins colocalize with CD9 on cell-surface and multivesicular body-derived exosomes, and the cytoplasmic tail of UPIIIa undergoes a conserved fertilization-dependent, Fyn-mediated tyrosine phosphorylation that also occurs in Xenopus laevis eggs. Uroplakin knockout and antibody blocking reduce mouse eggs’ fertilization rate in in vitro fertilization assays, and UPII/IIIa double-knockout mice have a smaller litter size. Phylogenetic analyses showed that uroplakin sequences underwent significant mammal-specific changes. These results suggest that, by mediating signal transduction and modulating membrane stability that do not require two-dimensional-crystal formation, uroplakins can perform conserved and more ancestral fertilization functions in mouse and frog eggs. Uroplakins acquired the ability to form two-dimensional-crystalline plaques during mammalian divergence, enabling them to perform additional functions, including umbrella cell enlargement and the formation of permeability and mechanical barriers, to protect/modify the apical surface of the modern-day mammalian urothelium.

High-end applications of single-walled carbon nanotube (SWNT) require detailed understanding of their binding affinity (Kd) with surfactants. Here, we quantitatively determined the comprehensive Kd and aggregation number (γ) of nine nonionic and anionic surfactants according to SWNT chirality. Photoluminescence (PL)-based titration using flavin mononucleotide (FMN)-SWNT complexes showing the largest redshifted optical transition enabled quantitative comparison of the surfactants and displayed distinct first and second regimes which correspond to partial and full replacements of FMN, respectively. Especially, the second transition exhibited sigmoidal PL change whose middle point denoted by the inverse of Kd slightly differs from critical micelle concentration of surfactant alone, depending on its functional groups. Moreover, nonionic surfactants displayed larger Kd and lower γ values than the anionic did. Specifically, Kd values between Pluronic F108 and sodium dodecyl sulfonate differ by four orders of magnitude. Such differences were rationalized in terms of the occupied volume of the micelle based on the hydrodynamic volume and γ. During the replacement, Kd and γ were affected by the degree of surfactant rearrangement induced by aging process, leading to more stable complex. Scaling the interactions between surfactant and SWNT provides useful guidelines to design novel SWNT sorting method using more than two surfactants.

Poly(2,6-dimethyl-1,4-phenylene oxide)s (PPOs)-based anion exchange membranes (AEMs) with four of the most widely investigated head groups were prepared. Through a combination of experimental and simulation approaches, the effects of the different types of head groups on the properties of the AEMs, including hydroxide conductivity, water content, physicochemical stability, and fuel cell device performance were fully explored. Unlike other studies, in which the conductivity was mostly investigated in liquid water, the conductivity of the PPO-based AEMs in 95% relative humidity (RH) conditions as well as in liquid water was investigated. The conductivity trend in 95% RH condition was different from that in liquid water but corresponded well with the actual cell performance trend observed, suggesting that the AEM fuel cell performance under in situ cell conditions (95% RH, 60 °C, H2/O2) is more closely related to the conductivity measured ex situ under 95% RH conditions (60 °C) than in liquid water. On the basis of the conductivity data and molecular simulation results, it was concluded that the predominant hydroxide ion-conducting mechanism in liquid water differs from that in the operating fuel cell environment, where the ionomers become hydrated only as a result of water vapor transported into the cells.

The dynamics of hydronium ions and methanol molecules in hydrated SPAES and blend membranes are investigated via molecular dynamics simulations using the COMPASS force field. In addition to calculating the diffusion coefficients as a function of the hydration level, an amorphous cell with a specific composition of H2O molecules and H3O+ determined from the experimental data is constructed and tested. The water and methanol diffusion coefficients are considerably smaller at lower hydration levels and room temperature. The diffusion coefficient of the water and methanol molecules increases with increases in the hydration level, and this is in good agreement with experiment data. Analysis of the pair correlation functions supports the experimental observations of the membrane performance with hydration related to the water and methanol diffusion behavior in hydrated SPAES and blend membranes.

Mixed metal oxide (MMO) with relatively homogeneous mesopores was successfully obtained by calcination and reconstruction of albumin-templated layered double hydroxide (LDH). The aggregation degree of albumin-template was controlled by adjusting two different synthesis routes, coprecipitation and reconstruction. X-ray diffraction patterns and scanning electron microscopic images indicated that crystal growth of LDH was fairly limited during albumin-templated coprecipitation due to the aggregation. On the hand, crystal growth along the lateral direction was facilitated in albumin-templated reconstruction due to the homogeneous distribution of proteins moiety. Different state of albumin during LDH synthesis influenced the local disorder and porous structure of calcination product, MMO. The N2 adsorption-desorption isotherms demonstrated that calcination on reconstructed LDH produced MMO with large specific surface area and narrow distribution of mesopores compared with calcination of coprecipitated LDH.

We assessed the groundwater quality in an industrial area (Tiruchendur Taluk) of Tamil Nadu state in coastal south India for human health risk from drinking as well as irrigation suitability by using the drinking water quality index (DWQI), irrigation factors (sodium adsorption ratio, sodium percentage, residual sodium carbonate and permeability index) and health hazard valuation (THQI- by consuming NO 3 − and F − ). About 57% of the samples represented Ca2+-Mg2+-Cl−-SO42− facies and the anthropological unhygienic inputs elevated the salinity. Our results indicated that all the samples are unsuitable for drinking (DWQI up to 1063) and almost half of them are also unsuitable for irrigation due to sodium risk. Total hazard quotient index (THQI; HQ nitrate and HQ fluoride) suggested the order of health risk as children > women > men with about 64%, 70% and 79% of the samples posing non-carcinogenic risks for men, women and children, respectively. Different mitigation measures and sustainable development should be enforced to minimize the health issues from contamination caused by industries, fertilizers in agro-fields and natural processes and reduce the sodium dominance in groundwater. The spatial distribution maps of this study could also be helpful in organization of proper treatment plans to provide safe and hygienic groundwater to the community.

Light plays an important role in the transcriptional regulation of photosynthetic apparatus. The influence of oxygen and light conditions on the protein expression of Rhodobacter sphaeroides was investigated using a proteomic approach. The R. sphaeroides was grown aerobically under dark cultivation (D24) and light cultivation (L24) for 24 h. An average of 950 distinguishable spots were obtained on 2-D analytic gel for D24 and L24 conditions, of which 48 proteins exhibited significant changes in protein expression levels. Among the 48, 31 proteins were upregulated and 17 proteins were downregulated in L24 when compared with D24. The results depict the comparative protein expression in R. sphaeroides mediated through growth under light or dark conditions. The data suggest that the overexpressed proteins, phosphoribosyl-ATP pyrophosphatase (HisE), in the D24/aerobic culture are involved in the positive regulation of PAC production can be functionally applied in metabolic engineering and industrial processes.