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Introduction Because blaCTX-M is responsible for resistance of bacteria to the third generation cephalosporins, location of blaCTX-M could be a good indicator for classifying bacterial isolates harboring blaCTX-M in molecular epidemiology. However, determination of blaCTX-M location has been difficult when multiple copies of ISEcp1 were found on bacterial genome. We aimed to establish a high-throughput analytical method for upstream genetic structures (UGS) of ISEcp1 to facilitate determination of blaCTX-M location. Methods Extracted DNA samples obtained from 168 Escherichia coli isolates possessing blaCTX-M were digested by restriction enzyme, HaeIII, and the digested DNA fragments were ligated with homemade barcode adaptors. Then, DNA fragments containing UGS of ISEcp1 were amplified and subjected to the Nanopore sequencer. Results Nucleotide sequences and locations of 168 UGSs obtained from the examined E. coli isolates were determined. Among the 168 determined UGSs, 150 (89.3%) UGS were confirmed on plasmid and classified into eight types. Interestingly, coding sequence of ISEcp1 transposase gene in seven of the eight types were disrupted by IS26 insertion. The remaining 18 (10.7%) UGSs were observed in identical chromosomal region. The obtained nucleotide sequences the locations of UGSs were confirmed by conventional capillary sequencer and Southern blotting, respectively, and any discrepant result was not observed with these confirmation procedures. Conclusions Our results indicated that the established method was efficient for simultaneously determining at least 100 different UGS, and suggested that the determined UGSs of ISEcp1-blaCTX-M transposition unit was useful for classification of bacterial isolates harboring blaCTX-M.

This paper analyzes recreation demand on the fringe of an urban center in Norway. Specifically, it investigates the potential impact of wind energy projects on local recreation values. Recreation areas near cities are often scarce and under increasing pressures from growing populations with associated real-estate development and expanding or emerging industries. Hence, public planners and policy makers who seek to make optimal resource management decisions need information on all opportunity costs, including those associated with diminished recreational access or quality. Two separate case studies utilize the travel cost method (TCM) to derive baseline recreation demands. Supplementary information from contingent behavior (CB) scenarios provides identification of the impact of wind turbines on recreation benefits. For a unique comparison, one case examines a possible inland wind farm near a popular local mountain area, whereas the other case examines an offshore wind farm near local beaches. Econometric estimations are performed in a joint revealed preference (RP) – stated preference (SP) pseudo-panel count-data framework. The analysis generates baseline consumer surplus estimates in the range of NOK 70–155 per trip and indicates that the wind turbines would have negative impacts that are both statistically and economically significant.

Coefficient of consolidation (Cv) is a measure of compressibility of soil. This coefficient is an important parameter which is used in the design of foundation of civil engineering structures and also in the slope stability analysis. In this study, the main objective is to propose a hybrid machine learning approach named MLP-BBO for the prediction of the coefficient of consolidation of soft soil. This method is based on Multi-layer Perceptron Neural Network (MLP) and Biogeography-based Optimization (BBO). For this, a total number of 164 soil samples were collected from the Tan Vu–Lach Huyen highway project and Ha Noi–Hai Phong highway project sites. In the modeling, input parameters used include clay (%), moisture content (%), liquid limit (%), plastic limit (%), plasticity index (%), and liquidity index (%). To validate performance of the models, standard methods such as Root-Mean-Square Error (RMSE), Mean Absolute Error (MAE), and correlation coefficient (r) were used. For the comparison of performance of the models, popular machine learning methods were used namely Backpropagation Multi-layer Perceptron Neural Networks (Bp-MLP Neural Nets), Radial Basis Functions Neural Networks (RBF-Neural Nets), Gaussian Process (GP), M5 Tree, and Support Vector Regression (SVR). Results of the model study indicate that the proposed method MLP-BBO has the highest predictive capability (RMSE = 0.397, MAE = 0.302 and r = 0.827), followed by the SVR (RMSE = 0.403, MAE = 0.299 and r = 0.819), the Bp-MLP Neural Nets (RMSE = 0.478, MAE = 0.398 and r = 0.805), the RBF-Neural Nets (RMSE = 0.412, MAE = 0.281 and r = 0.804), the GP (RMSE = 0.440, MAE = 0.301 and r = 0.777), and the M5 Tree (RMSE = 0.494, MAE = 0.322 and r = 0.728), in the prediction of Cv, respectively. Therefore, it can be concluded that though performance of all applied models is good in the prediction of the coefficient of consolidation of soil but performance of the MLP-BBO is the best.

NiS is a highly promising transition metal sulfide versatile for a sensor material owing to its superior conductivity and stability, and herein we report its first incorporation into an electrochemical sensor. Because exposure to electrolyte under electrochemical impact can easily deform NiS, thereby decreasing its electro-activity and measurement reproducibility, a strategy for optimally integrating NiS into sensors is critically necessary. For this purpose, NiS was initially firmly affixed to a mechanical pencil lead (MPL) by means of hydrothermal deposition (with the result designated as MPL-NiS). MPL, a commercially available carbon-based material with consistent quality, was adopted to make the sensor cost-effective and easily prepared. Then, to prevent direct exposure of NiS to samples during electrochemical measurement and to make the sensor surface more reactive for wide variety of analytes, reduced graphene oxide (rGO) was electrodeposited on the NiS surface to construct a final structure of MPL-NiS/rGO. In summary, NiS, a p-type semiconductor with positive charge, was effectively composited and sandwiched with negatively charged rGO and MPL by means of mutual electrostatic interaction. When the developed MPL-NiS/rGO sensor was used to separately measure bisphenol A (BPA) and mercury- Hg2+, the sensitivity and sensor-to-sensor reproducibility were comparable with or superior to those of previously reported sensors.

The present work reports on the morphological influence of catalyst on oxygen reduction reaction (ORR). As a catalyst, Prussian blue analog structured nickel hexacyanoferrate (Ni-HCF) with two distinct morphologically controlled frameworks, viz. granular crystalline bulk film and rose-petal like structured thin film having smooth surface, are synthesized via controlled anodization route, and their morphological influence on the ORR is investigated. In addition, the influence of addition of carbon black, which is commonly used as catalytic dispersing support, is also studied on the catalytic mechanism for the ORR. Based on the hydrodynamic voltammetry of the electrocatalytic films on rotating disk electrode, the number of electrons involved in the reduction of an O2 molecule, and the kinetic current density of the reaction are estimated. While the pristine Ni-HCF frameworks based catalyst, regardless of their morphology, demonstrates the direct reduction of O2 with participation of 4 electrons, the frameworks when mixed with carbon black as support diverts the reduction via two steps with participation of 2 electrons at each step. A larger kinetic current density is, however, obtained in the case of granular crystalline bulk film of the Ni-HCF frameworks.

Groundwater plays a key role in public water supplies around the world, and consideration of the social dimension is a key issue in sustainable groundwater management. In Hanoi, the capital of Vietnam, the situation of groundwater resources is disastrous because the quality has seriously degraded recently. Hence, in this study, a social sustainability assessment framework of groundwater resources with a focus on Hanoi is proposed for the first time. An analytical hierarchy process (AHP) approach was used to generate the main components (aspects and indicators) of this framework, which has been considered one of the most challenging tasks in AHP sustainability applications. To overcome these challenging tasks, we carefully reviewed and explored the current problems of Hanoi groundwater resources to propose 3 main aspects (quantity, quality, and management) and appropriately selected their 13 sustainability indicators for this target area. We introduce a sustainability index function (SIF) for indicators to clarify the relationship between each indicator value and its sustainability index. Furthermore, we consider both the conventional linear relationship, as it is usually developed in the literature, as well as a non-linear SIF to arrive at a reasonable sustainability assessment. For the Hanoi case study, the sustainability indices obtained using a combined linear and non-linear SIF method reflect the current problems well, that is, the social sustainability assessment is closer to reality. The sustainability indices of the quantity, quality, and management aspects of the groundwater were appropriately assessed as good, poor, and acceptable, respectively, resulting in Hanoi being rated at the acceptable level in the final social sustainability assessment. This result reveals that the population of Hanoi is satisfied with the quantity of water but dissatisfied with its current poor quality and its relatively high price.

From the stems of Paramignya trimera (Rutaceae), two new prenylated phenolic compounds, paratrimerins G (1) and H (2), together with 24 known compounds, as well as their α-glucosidase inhibitory activity was examined. Paratrimerins G (1) and H (2) showed moderate inhibitory effect, with the IC50 values of 89.2 and 58.8 μM, respectively. The plausible biosynthetic pathways of two new compounds was proposed.

This work reports on back-electron injection barrier property and electrical charge storing behavior of PEDOT film with and without substituted propylene as terminal group. As a barrier layer, thin polymer film is deposited on TiO 2 particles of DSSC using photo-induced polymerization route. The same piece of DSSC device is used before and after deposition of polymer thin-film for studying the influence of interfacial treatment. The propylene substituted PEDOT treatment of the device demonstrates an enhanced power conversion efficiency from 4.31 to 5.96% whereas the unsubstituted PEDOT treated device shows only the power conversion enhancement from 4.54 to 5.31%. This finding suggests the higher barrier performance of the propylene substituted PEDOT for back-electron injections. Unlike the barrier performance, the propylene substituted PEDOT shows poorer electrical charge storing behavior with specific capacitance of 63.47 F g −1 whereas the unsubstituted PEDOT film achieved 96.84 F g −1 .

This work reports the influence of thermal treatment on electrocatalytic water oxidation/reduction behaviors of one dimensional CoTe nanotube film deposited on FTO substrate from aqueous solution at room temperature. The optimally annealed film at 200 °C demonstrates substantially better electrocatalytic properties, which can be ascribed to the enhanced electrochemical active surface area and electrical conductivity obtained by improving the intergranular connectivity. In addition, the annealed nanotube film demonstrates highly competitive performance to that of many outstanding electrocatalysts for overall splitting of alkaline water to generate hydrogen as green fuel with the oxygen evolution reaction overpotential of 0.37 V (without iR-compensation) for the benchmark current density of 10 mA cm−2.

Nano-heterojunctions of n-ZnO/p-Co3O4 with varying molar ratios of Co3O4 derived from a zeolitic imidazolate framework (ZIF-8/ZIF-67) were efficiently synthesized and well-characterized. The heterojunction-based gas sensors were then used for sensing various gases, including ethanol. Owing in part to the ZIF-8/ZIF-67 structure, the calcined n-ZnO/p-Co3O4 with 30 mol% Co3O4 was the best sensor, in-terms of high response, outstanding selectivity, and good repeatability for low concentrations of ethanol at 300 °C. According to detailed analysis, the high ethanol-sensing performance of the n-ZnO/p-Co3O4 nanocomposite could be attributed to the high-porosity of sensing materials, formation of p-n heterojunction at interfaces, the catalytic ability of Co3O4, and the high crystallinity of the ZnO phase in the nano-heterojunctions.

Functionalization of BODIPY dyes with TPP substituents endowed them with mitochondria-targeting capabilities. The uniodinated BODIPY control displayed good biocompatibility, low cytotoxicity in the dark, and exceptional cellular imaging capabilities; however, it did not exhibit photodynamic therapeutic properties upon excitation at 530 nm. Dual functional photosensitizers were obtained in the case of mono- and di-iodinated BODIPY derivatives, which exhibited mitochondria-targeting capabilities and provided clear fluorescence confocal bioimages, while efficiently generating high levels of singlet oxygen species and displaying photodynamic therapeutic activity toward two cancer cell lines following LED irradiation. Overall, the results presented herein demonstrate the considerable potential for the use of TPP-functionalized BODIPY dyes as viable agents for fluorescence-imaging-guided photodynamic therapy (PDT) for cancer treatment.

Macroeconomic factors are regarded as important determinants of corporate leverage decisions, although their importance during good and bad times is less understood. We examine the effect of macroeconomic factors on total, long-term and short-term corporate leverage (debt to total assets) decisions during: (1) the expansionary and contractionary phases of the business cycle; and (2) the financial crisis (FC) and non-FC period. This paper explains leverage decisions for S&P 500 non-financial firms over the period 1985–2017. Our main results are as follows. Short-term leverage and interest rate are positively related. Long-term leverage, on the other hand, is negatively associated with inflation. Interest rate and inflation effects are stronger during the expansionary phases of the business cycle and non-FC period, while the impact of US economic activity is stronger during the contractionary phases of the US business cycle.

We report the modulation of the dual photo/thermo-responsive multicolor fluorescence from poly( N -isopropyl acrylate) pNIPAM-based nanogels. The thermo-responsive pNIPAM-crosslinked matrix was covalently copolymerized with nitrobenzoxadiazole (NBD) monomers as a Forster resonance energy transfer (FRET) donor and electrostatically conjugated with photochromic spiropyran (SP) dyes as a FRET acceptor. The pristine nanogel emits green fluorescence derived from the NBD moieties; however, the irradiation of the nanogels with UV light led to the transformation of the ring-closed colorless SP moieties to the ring-opened coral-red merocyanine (MC) moieties, resulting in light-pink fluorescent nanogels. Notably, at higher temperatures, the fluorescence of the nanogels was red-shifted and enhanced by the more efficient FRET process. The nanogels were well-distributed in the cellular cytoplasm and showed excellent photochromic function in the subcellular environment for applications as photo-switchable bio-imaging agents and nanothermometers.

Lithium-sulfur (Li–S) batteries are considered promising candidates for next-generation energy storage devices due to their ultrahigh theoretical gravimetric energy density, cost-effectiveness, and environmental friendliness. However, the application of Li–S batteries remains challenging; mainly due to a lack of understanding of the complex chemical reactions and associated equilibria that occur in a working Li–S system. A new approach preparing graphene-based active cathode materials of Li-S battery with spatially confined lithium sulfides is reported. The starting graphene-embedded 2D-MoS2 was synthesized by a solvothermal method in organic solvents followed by the calcination of trapped organic solvent molecules at 800 °C to give graphene single sheets inside the 2D-MoS2 layers with 7 A distance (MoS2-Gr-32.51). Then, it was electrochemically reduced/lithiated at potential 0.01 V vs Li+/Li generating metallic molybdenum and lithium sulfides. As a result, the structure of MoS2 multi-layers collapsed. The graphene multi-layer (ML-Graphene) was left behind and shut the lithium sulfides between the layers. The sizes of Li2Sn (n = 4–6) are bigger than the inter-layer distance of ML-Graphene, and the escape of sulfur/sulfides from the cathode into the electrolyte is physically blocked alleviating shuttle effects. The specific capacity of ML-Graphene/lithium sulfides cathode was high of 1209 mAh/gMoS2-Gr at 0.1 C (1 C = 670 mA/g). The ML-Graphene exhibited the remarkable lithium intercalation capability, and the theoretical calculation has been carried out to give 2231.4 mAh/g. Such high capacity was hybridized with the theoretical capacity of sulfur (1675 mAh/g), and the ML-Graphene composite with dichalcogenides (2D-MoS2) became a promising platform for the cathode of Li-S batteries.

The mining sector faces some of the most difficult sustainability challenges of any industrial sector. The mining sector is remarkably significant to the development of the Asia-Pacific Economic Cooperation (APEC) region, because the majority of global trade and investment in this region depends on this sector. Therefore, the assessment of mining sector sustainability at national and global scales in APEC economies is an important task. So far, however, mining sector sustainability assessment frameworks have only been developed at small scales, such as companies and cities. In this study, therefore, it is proposed an indicator-based sustainability assessment framework (iSAF) to assess mining sector sustainability at national and global scales. In this framework, fuzzy logic was utilized to adequately deal with the uncertainty and vagueness of human expressions. The conventional fuzzy scales were suitably modified in the proposed framework to facilitate confident decision-making by the relevant stakeholders. In order to avoid repeatedly conducting the judgment until the acceptable consistency was obtained, iSAF implemented an innovative theory to deal with unacceptable consistencies in judgment. The proposed iSAF was applied to the mining sector of APEC economies using data from the APEC 2010 Project. As for the results, three important criteria including economic, environmental, and social criteria and twenty significant indicators were appropriately selected to cover the actual situation in the sector. The results showed that iSAF was a suitable framework for preventing uncertainty and vagueness in decision-making. iSAF was found to provide crucial support to decision-makers, not only in identifying and structuring the main components contributing to sustainability, but also in pointing out the factors in which significant investment should be made to effectively improve sustainability.

The screening and monitoring of residual antibiotics in pork meat were conducted in Ho Chi Minh City, Vietnam, from 2014 to 2015. One hundred samples collected from a wholesale market were screened on-site using a microbiological kit, and eighteen samples were determined as positive for residual antibiotics. Once transferred to the lab, all the samples were analyzed for 28 antibiotics using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Sulfamethazine residues (11–1600 μg/kg) were detected in 23 samples by LC-MS/MS. Notably, 11 samples with sulfamethazine concentrations ranging from 310 to 1600 μg/kg were detected as “positive” in the initial screening, whereas 12 other samples with sulfamethazine levels below 200 μg/kg were screened as “negative”. No other targeted antibiotics were identified among the remaining positive samples. These results show the potential and limitations of a monitoring system combining on-site microbiological tests and an LC-MS/MS method.

The present study was undertaken to examine the apoptotic status and meiotic progression of oocytes from small follicle (SF; 0.5-2 mm in diameter) and medium follicle (MF; 3-6 mm in diameter) when the oocytes were denuded before, during, and after IVM. Cumulus-oocyte complexes (COCs) were collected from SF or MF of prepubertal gilt ovaries. Before or 20 hours after the start of IVM culture, some oocytes were denuded and cultured for IVM. At the end of IVM, apoptotic status and meiotic progression of the oocytes were compared with oocytes matured in the presence of cumulus cells (CCs) by Annexin-V/PI assay and 4',6-Diamidino-2-phenylindole staining. Apoptotic status of the oocytes was only affected by time when the oocytes were denuded. In both oocytes from SF and MF, although the incidence of early and late apoptotic oocytes was significantly higher when the CCs were removed before IVM, the rate was significantly lower when CCs were removed 20 and 44 hours after the start of IVM. The incidence of mature oocytes was significantly affected by both the origin of COCs and time when oocytes were denuded from the COCs. Although the percentage of mature oocytes was higher in MF than SF, maturation rates were significantly higher when oocytes were denuded 20 hours, as compared with 0 and 44 hours after the start of IVM. However, the percentage of mature oocytes with a morphologically normal spindle was significantly higher when oocytes were denuded 44 hours, rather than 22 hours of IVM. In conclusion, removing CCs 20 hours after the start of IVM seems to promote meiotic progression of the oocytes to the metaphase-II stage even when the COCs were collected from SF, although factor(s) from or communication with CCs during IVM may need to obtain a morphologically normal spindle in mature oocytes.

Prior studies on chief executive officer (CEO) compensation have mainly focused on large firms from a broad spectrum of industries. This study aims to provide further evidence on the determinants of CEO compensation for small, homogeneous firms. Using a sample of Australian early-stage mining exploration entities (MEEs) over the 2004−2017 period, we document a set of predictors of CEO compensation that are unique to this group of firms. First, fluctuations in commodity prices are found to be positively associated with CEO stock options value. Second, we find that signals of MEEs’ future prospects, conveyed through additions to and acquisition of capitalised exploration and evaluation expenditure, have positive impacts on CEO compensation. Third, proceeds from equity raisings indicate CEOs’ effort and skills to improve shareholder wealth, resulting in higher compensation. Lastly, we find some evidence supporting the relevance of non-executive directors’ advisory role over their monitoring role.

From July 2017 to Jan 2019, a total of 572 retail fresh vegetables were collected to clarify the contamination of Salmonella in the Mekong Delta, Vietnam. Salmonella was isolated from 74 (12.9%) of 572 samples. The isolation rate of Salmonella from retail fresh vegetables in the rainy season (15.3%) was significantly higher than that in the dry season (7.6%) (P

This work reports on in-situ doping of Fe(III) redox centers to Ni Co based Prussian blue analogue framework films and their eletrocatalytic performance towards water splitting into molecular hydrogen and oxygen. Uniform and self-supported films of frameworks are deposited onto nickel substrate via anodization in 80 vol % glycerol based aqueous electrolyte containing 0.1 M K3[Co(CN)6] with/without addition of a small amount of [Fe(CN)6]3− as doping precursor. XRD, HR-TEM, STEM and XPS characterization of the film confirmed the doping. Notably, the doped film demonstrated an enhanced electrocatalytic activity towards hydrogen and oxygen evolution reaction in alkaline electrolyte with small overpotentials of 169 and 263 mV, respectively to derive the benchmark current density of 10 mAcm−2. In addition, bulk electrolysis at 10 mAcm−2 demonstrated an improved and well-maintained long-term electrochemical durability of the doped film-based cathode and anode for overall splitting of water.

This work presents an epitaxial deposition of a thin film of single crystal MoTe2 nanorods via electrodeposition at room temperature from aqueous based electrolyte purged with argon. The method allows control over film morphology through deposition potential. In a typical deposition performed at −0.8 V vs Ag/AgCl for 10 min, film comprised of 1D MoTe2 nanorods is obtained, while the deposition at −0.9 V vs Ag/AgCl renders nanoplate like structure. When characterized with FE-SEM, XRD, TEM, SAED and Raman spectroscopy, the film shows uniform deposition of single crystal MoTe2 nanorods particularly with metallic 1 T’ phase. In a preliminary test on feasibility of the nanorod film as anode material for Li-ion storage, a promising result is perceived showing discharge capacity of about 770 mAhg−1 with good electrochemical reversibility.

Exposing to adverse childhood experiences (ACEs) has been identified as one of the major contributing factors to poor mental health and suicide in adolescents. However, little is known about this relationship in Vietnamese adolescents. This study aimed to evaluate the effect of ACEs on depression, psychological distress and suicidal thought among Vietnamese adolescents across different areas in Vietnam. Cross-sectional surveys were conducted among 4957 secondary school and high school students aged 13-20 in urban area, rural area, border area and mountainous area. The students were asked to complete a self-report questionnaire which included the Center for Epidemiological studies - Depression, the Kessler-10 and ACE questionnaire from the WHO Adverse Childhood Experiences Study. Suicidal thought was evaluated by a single question from the U.S. Youth Risk Behavior Survey. Among 4720 students included in the analysis, 54.4% were female. The prevalence of depression, psychological distress and suicidal thought was 22.9%, 30.6% and 10.9% respectively. About 86% of participants experienced at least one type of ACEs and nearly 56% reported multiple types of ACEs. Students with four or more types of ACEs had 6.98 (95% CI 5.09 -9.56), 4.72 (95 % CI 3.58-6.23) and 6.43 (95 % CI 4.45-9.30) times higher in odds of having depression, psychological distress and suicidal thought respectively. In conclusion, ACEs are common in Vietnamese adolescents and are strongly associated with depression, psychological distress and suicidal thought. Our finding indicates urgent needs for interventions targeting both ACEs and depression, psychological distress in Vietnamese adolescents.

In this study, the main objective is to develop and compare several advanced Artificial Intelligent (AI) models namely Adaptive Network based Fuzzy Inference System optimized with Particle Swarm Optimization (PSOANFIS), Artificial Neural Networks (ANN) and Support Vector Machines (SVM) for the prediction of daily rainfall in Hoa Binh province, Vietnam. For this, meteorological variable parameters such as maximum temperature, minimum temperature, wind speed, relative humidity and solar radiation were collected and used as input parameters and daily rainfall as an output parameter in the models. Validation of the developed models was achieved using various quality assessment criteria such as correlation coefficient (R) and Mean Absolute Error (MAE), Skill Score (SS), Probability of Detection (POD), Critical Success Index (CSI), and False Alarm Ratio (FAR). The results showed that all the AI models provided reasonable predictions of daily rainfall but the SVM was found to be the best method for predicting rainfall. This method was also found to be the most robust and efficient prediction model while taking into account of input variability using the Monte Carlo approach. This AI based study would be helpful in quick and accurate prediction of daily rainfall.

Hf- and Zr-based metal-organic frameworks are highly stable and porous materials that have been attracted in many applications, especially in biomedicine. The materials are commonly synthesized via solvothermal reaction between Hf or Zr salts and organic linkers, however this method requires elongated reaction time as well as results in heterogeneous particles and low yield, which leads to the difficulty for nano MOF synthesis. To overcome these disadvantages, we applied microwave method to enhance the synthetic efficiency and control particle homogeneity of nano UiO-66 framework. The nano MOFs, named Hf-UiO-66 and Zr-UiO-66, with highly homogeneous nanoparticles, very small sizes and high yields could be formed under microwave irradiation within a few minutes. According to the results from XRD, SEM, N2 isotherm sorption, and TGA characterizations, the materials exhibited similar porosity and structure compared to the original framework. Additionally, Hf-UiO-66 and Zr-UiO-66 showed high efficiency for the treatment of curcumin's overdose by adsorbing the drug from aqueous solution with a maximum adsorption capacity up to 463.02 and 466.39 mg g−1, respectively, higher than reported Zr-UiO-66 (393.22 mg g−1). Moreover, the adsorption mechanisms were revealed that the adsorption of curcumin (CUR) by UiO-66 was influenced by defect sites in the MOF structure.

We investigated the mechanism and sensing efficiency of an anthracene-based fluorescent water-content chemosensor (AMG) containing a guanidine moiety in water-miscible organic solvents. Based on spectroscopic and theoretical results, we established that there are two functions of water for AMG in organic solvents, one of which is as a reagent for protonation and the other is in the solvation and stabilization of ionic products, such as protonated AMG (AMGH+) and hydroxide ion. Moreover, the effective solvation and stabilization of ionic products in organic solvents are critical for the mitigation of the deprotonation between them and the relatively high ratio of the fluorescence turn-on AMGH+ species. In 1,4-dioxane with low polarity, AMGH+ and hydroxide ion cannot be effectively solvated, and there is a strong positive correlation between the fluorescence intensity and volumetric fraction of water due to the improved solvation condition caused by the co-existent water. Conversely, the amount of water in polar solvents is less significant, as evidenced by the relatively small increase in the fluorescence intensity upon increasing the water content. This is because ionic products can be stabilized by polar organic solvent molecules without cooperation with water. Conclusively, the solvation and stabilization of ionic products produced by a chemical reaction at a chemical sensing site in a fluorescent chemosensor are important for determining the relative ratio between the fluorescence turn-on and –off species and the overall sensing efficiency of the fluorescent chemosensors.

The purpose of this study is to prepare and characterize the potential edible packaging films based on chitosan and Sonneratia caseolaris (L.) Engl. leaf extract (SCELE) into matrix. The incorporation of SCELE into Chitosan matrix was conducted with various contents (1–3 % wt) and the chitosan-based film samples were investigated. The effects of SCELE on the physical properties and antimicrobial activity of samples were also characterized. The Vietnamese banana fruit was chosen for food preservation and the appearance of banana coated with and without chitosan-based composite films was evaluated. The results indicated that the presence of SCELE can improve the antimicrobial activities, water vapor barriers while a significant decrease in light transmittance was found. Furthermore, the tensile strength and thermal stability were not affected by the addition of 2 % wt SCELE. Bananas coated with composite film based on chitosan matrix and SCELE had longer life time than control sample and those coated with pure chitosan film, indicating that the combination of SCELE into chitosan matrix brings potential application for active edible food packaging.

A theoretical study on antioxidant properties of fourteen xanthones extracted from the pericarp of G. Mangostana has been performed. Three main reaction mechanisms are investigated: hydrogen atom transfer (HAT), single electron transfer–proton transfer (SETPT) and sequential proton loss electron transfer (SPLET). The O H bond dissociation enthalpy (BDE), ionization energy (IE), proton affinity (PA) and electron transfer energy (ETE) parameters were computed in gas phase and water. The results show that HAT would be the most favorable mechanism for explaining antioxidant activity of xanthones in gas phase, whereas the SPLET mechanism is thermodynamically favored in water.

This work reports a facile solution based chemical transformation of thin film of CdCO3 cuboids into Cd-based Prussian blue analogue structured thin film with controlled redox-state by manipulating the anion exchange reaction between the solid film and the aqueous solution of K3[Fe(CN)6] at 60 °C. The progress of the transformation reaction is monitored via electron microscopy, X-ray difractometry and X-ray photoelectron spectroscopy. Based on the scenario of the reaction progress revealed by these analysis, the CdCO3 cuboids are first found to be transformed into the smaller cuboids of cadmium ferricyanide, which, on further reaction, are transformed into the cadmium ferrocyanide cuboids. Thus, by controlling the redox-state of the Fe-metal center on the frameworks, the electrocatalytic activity of the frameworks on oxygen reduction reaction (ORR) is studied. The electrocatalytically inert CdCO3 cuboids after transformation to the frameworks with Fe3+-centers demonstrate an enhanced catalytic activity on ORR, while the Fe2+-centers of the frameworks are found to relegate the catalytic activity, thereby manifesting the redox-sate modulated ORR activity of the frameworks. To the best of the authors' knowledge, this is the first report of this kind on redox-state specific ORR activity.

Flexible operation of post-combustion CO2 capture (PCC) plants can improve efficiency through coordinating the balance between consumer demands for electricity and CO2 emission reductions. This strategy however, will impose process disturbances while the PCC plant is ramped up, ramped down or turned off. This paper presents the preliminary development of a dynamic model for PCC in a brown coal-fired power plant using the process simulation software Aspen Plus Dynamics. Validation of the dynamic model will be against both steady state and dynamic data from the pilot plant. By gaining this understanding of the dynamic behavior, the technical and financial performance of PCC can be optimised.

The effect of cationic liposome prepared from 1,2-dioleoyl-3-trimethyl- ammonium-propane (DOTAP) on the gene expression at the mRNA translation level was investigated using an E. coli cell-free translation system. DOTAP liposome at 3 mM inhibited the mRNA translation of green fluorescent protein (GFP), as indicated both by the fluorescence intensity of GFP and by SDS-PAGE analysis. The role of DOTAP liposome on the inhibition of mRNA translation was revealed that the cationic quaternary amine groups on the liposome surface can interact and neutralize the anionic phosphate groups on mRNA by an electrostatic interaction. mRNA molecules still existed without any degradation in the presence of DOTAP liposome although it could not be translated. These results clearly illustrated that the DOTAP liposome could knock down mRNA and silence its activity of translation in an E. coli cell-free system.

Mechanisms that regulate cellular metabolism are a fundamental requirement of all cells. Most eukaryotic cells rely on aerobic mitochondrial metabolism to generate ATP. Nevertheless, regulation of mitochondrial activity is incompletely understood. Here we identified an unexpected and essential role for constitutive InsP 3R-mediated Ca 2+ release in maintaining cellular bioenergetics. Macroautophagy provides eukaryotes with an adaptive response to nutrient deprivation that prolongs survival. Constitutive InsP 3R Ca 2+ signaling is required for macroautophagy suppression in cells in nutrient-replete media. In its absence, cells become metabolically compromised due to diminished mitochondrial Ca 2+ uptake. Mitochondrial uptake of InsP 3R-released Ca 2+ is fundamentally required to provide optimal bioenergetics by providing sufficient reducing equivalents to support oxidative phosphorylation. Absence of this Ca 2+ transfer results in enhanced phosphorylation of pyruvate dehydrogenase and activation of AMPK, which activates prosurvival macroautophagy. Thus, constitutive InsP 3R Ca 2+ release to mitochondria is an essential cellular process that is required for efficient mitochondrial respiration and maintenance of normal cell bioenergetics. © 2010 Elsevier Inc., link_to_subscribed_fulltext

The role of the charged liposome on the in vitro expression of green fluorescent protein (GFP) was investigated, focusing on its elemental steps such as transcription, translation and folding. The total GFP expression was enhanced to 145% when a neutral liposome (POPC: 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocoline) was added externally to a cell-free translation system. On the contrary, the addition of the charged liposome composed of POPC with anionic 1-palmitoyl-2-oleoyl-sn-glycero-3-[phospho-rac-(1-glycerol)] (POPG) or cationic stearyl amine (SA) inhibited the total GFP expression, depending on the surface charge density of liposome. In transcription, the RNA synthesis was enhanced regardless of the variation of the surface charge, indicating that transcription was enhanced due to the stabilization of RNA structure by its hydrophobic interaction with liposome. Translation was inhibited by cationic liposome although it was enhanced by anionic liposome and neutral liposome. On the other hand, the folding was not inhibited in the presence of neutral liposome, whereas anionic liposome and cationic liposome inhibited the folding in proportion to the their surface charges, suggesting that the total GFP expression was controlled by a charged liposome in the translation step and folding step.

Even in the presence of an adequate oxygen supply, many tumors metabolize the majority of the glucose they take up through glycolysis. It has been a long-held belief that this glycolytic phenotype is due to cancer-specific defects in mitochondrial oxidative phosphorylation. In this issue of Cancer Cell, Fantin et al. now report that most tumor cells have a substantial reserve capacity to produce ATP by oxidative phosphorylation when glycolysis is suppressed. These new data add to mounting evidence that the high rate of glycolysis exhibited by most tumors is required to support cell growth rather than to compensate for defect(s) in mitochondrial function.