bluuebunny/crossref_metadata_2025 huggingface dataset:
Correlation between Concentrations of Ni and Y in Y-Doped BaZrO3 Electrolyte in Co-Sintered Cells: A Case of Controlled NiO Activity by Using MgO-NiO Solid Solution as Anode Substrate
Authors: Han Donglin , Kuno Kenji , Uda Tetsuya
Published: August 2019

BaZr0.8Y0.2O3-δ (BZY20) is promising to be applied as an electrolyte in fuel cells, electrolysis cells, etc. However, when a half cell composed of a BZY20 electrolyte layer and a BZY20-NiO composite anode substrate is co-sintered (1400–1600 °C), Ni diffuses from the anode substrate into the electrolyte layer. Y content in the electrolyte layer decreases dramatically, since BZY20 cannot be equilibrated with NiO at such high temperature. Such Ni diffusion and Y loss are detrimental to the electrochemical performance of the electrolyte layer. In this work, we added MgO-NiO solid solution into the anode substrate to adjust the NiO activity (aNiO) during the co-sintering process, and used three different co-sintering methods to control the BaO activity (aBaO). The results revealed that by decreasing aNiO in the system, the as-co-sintered electrolyte layer had the composition shifting towards the direction of high Y and low Ni cation ratios. A clear correlation between the intra-grain concentration of Ni and Y was confirmed. In other words, to prepare the electrolyte with the same Y cation ratio, the Ni diffusion into the electrolyte layer can be suppressed by using the MgO-NiO solid solution with a high MgO ratio and a low Ni ratio. Moreover, by increasing aBaO, we found that the Y cation ratio increased and approached the nominal value of the pristine BZY20, when Mg1−xNixO (x = 0.3 and 0.5) was used. In summary, both aNiO and aBaO play important roles in governing the composition of the electrolyte layer prepared by the co-sintering process. To evaluate the quality of the electrolyte layer, both the intra-grain Y and Ni concentrations should be carefully checked.
Influence of Inclusions on the Mechanical Properties of RAFM Steels Via Y and Ti Addition
Authors: Qiu Guoxing , Zhan Dongping , Li Changsheng , Yang Yongkun , Qi Min , Jiang Zhouhua , Zhang Huishu
Published: August 2019

The effects of the Y- and Ti-containing inclusions on the tensile and impact properties of reduced activation ferritic martensitic (RAFM) steels were evaluated. Four steels with different Y and Ti contents were produced via vacuum induction melting. The size and quantity of inclusions in the steels were analyzed using scanning electron microscopy, and the oxide particle formation mechanism was clarified. These inclusions helped to enhance the pinning effect of the austenite grain boundaries based on the Zener pinning force. The average prior austenite grain sizes, measured via the linear intercept method, were 12.34 (0 wt.% Ti), 9.35 (0.010 wt.% Ti), 10.22 (0.030 wt.% Ti), and 11.83 (0.050 wt.% Ti) μm for the four steels, in order of increasing Ti content, respectively. Transmission electron microscopy was conducted to observe the fine carbides. The strength and impact properties of the steel containing 0.010 wt.% Ti were improved, and the ductile-to-brittle-transition temperature was reduced to −70.5 °C. The tensile strength and impact toughness of the steel with 0.050 wt.% Ti were significantly reduced due to the coarsening of both the inclusions and grain size, as well as the precipitation of large TiN inclusions. The RAFM steel with approximately 0.015 wt.% Y and 0.010 wt.% Ti exhibited an optimized combination of microstructures, tensile properties, and impact properties among the four steels.
rMSIKeyIon: An Ion Filtering R Package for Untargeted Analysis of Metabolomic LDI-MS Images
Authors: del Castillo Esteban , Sementé Lluc , Torres Sònia , Ràfols Pere , Ramírez Noelia , Martins-Green Manuela , Santafe Manel , Correig Xavier
Published: August 2019

Many MALDI-MS imaging experiments make a case versus control studies of different tissue regions in order to highlight significant compounds affected by the variables of study. This is a challenge because the tissue samples to be compared come from different biological entities, and therefore they exhibit high variability. Moreover, the statistical tests available cannot properly compare ion concentrations in two regions of interest (ROIs) within or between images. The high correlation between the ion concentrations due to the existence of different morphological regions in the tissue means that the common statistical tests used in metabolomics experiments cannot be applied. Another difficulty with the reliability of statistical tests is the elevated number of undetected MS ions in a high percentage of pixels. In this study, we report a procedure for discovering the most important ions in the comparison of a pair of ROIs within or between tissue sections. These ROIs were identified by an unsupervised segmentation process, using the popular k-means algorithm. Our ion filtering algorithm aims to find the up or down-regulated ions between two ROIs by using a combination of three parameters: (a) the percentage of pixels in which a particular ion is not detected, (b) the Mann–Whitney U ion concentration test, and (c) the ion concentration fold-change. The undetected MS signals (null peaks) are discarded from the histogram before the calculation of (b) and (c) parameters. With this methodology, we found the important ions between the different segments of a mouse brain tissue sagittal section and determined some lipid compounds (mainly triacylglycerols and phosphatidylcholines) in the liver of mice exposed to thirdhand smoke.
Programmable Paper-Based Microfluidic Devices for Biomarker Detections
Authors: Soum Veasna , Park Sooyong , Brilian Albertus Ivan , Kwon Oh-Sun , Shin Kwanwoo
Published: August 2019

Recent advanced paper-based microfluidic devices provide an alternative technology for the detection of biomarkers by using affordable and portable devices for point-of-care testing (POCT). Programmable paper-based microfluidic devices enable a wide range of biomarker detection with high sensitivity and automation for single- and multi-step assays because they provide better control for manipulating fluid samples. In this review, we examine the advances in programmable microfluidics, i.e., paper-based continuous-flow microfluidic (p-CMF) devices and paper-based digital microfluidic (p-DMF) devices, for biomarker detection. First, we discuss the methods used to fabricate these two types of paper-based microfluidic devices and the strategies for programming fluid delivery and for droplet manipulation. Next, we discuss the use of these programmable paper-based devices for the single- and multi-step detection of biomarkers. Finally, we present the current limitations of paper-based microfluidics for biomarker detection and the outlook for their development.
Formation of the Granodiorite-Hosting Magushan Cu–Mo Polymetallic Deposit in Southern Anhui, Eastern China: Evidences from Geochronology and Geochemistry
Authors: Qi Huasheng , Lu Sanming , Yang Xiaoyong , Zhou Yuzhang , Zhao Lili , Deng Jianghong , Li Jianshe
Published: August 2019

The newly discovered Magushan Cu-Mo polymetallic deposit, located in southeastern Anhui, eastern China, is a middle-scale skarn-type polymetallic deposit with different ore types of veinlets-disseminated skarn (the primary type), quartz veins, and porphyry. LA-ICP-MS zircon U–Pb analyses yielded a crystallization age of 135.7 ± 1.5 Ma for the ore-related granodiorite in Magushan. The granodiorites are I-type granites in nature, characterized by metaluminous and high-K calc-alkaline characteristics. They are enriched in large ion lithophile elements (LILEs, e.g., Ba, Th, and U) and light rare earth elements (LREEs), and depleted in high field strength elements (NFSEs, e.g., Nb, Ta, and Ti) and heavy rare earth element (HREEs), with slightly negative Eu anomalies (Eu/Eu* = 0.81–0.86). These granodiorites show high Mg# (mainly > 40) values, high MgO (1.73–1.96 wt. %) and low Na2O (<4.21 wt. %) contents, with whole-rock (87Sr/86Sr)i ratios (0.708877 to 0.710398), negative εNd(t) values of −5.4 to −5.2, and negative zircon εHf(t) values of −4.60 to −1.37, with old two-stage Hf model ages (TDM2) between 1.2‒1.5 Ga. Besides, they are characterized by high radiogenic Pb isotopic compositions with (206Pb/204Pb)i = 18.44–18.56, (207Pb/204Pb)i = 15.66–15.67, and (208Pb/204Pb)i = 38.77–38.87. These granodiorites are characterized by high zircon Ce4+/Ce3+ ratios (average 893) and Eu/Eu* ratios (average 0.51), indicating high magmatic oxygen fugacities. The distinct geochemical and isotopic features suggest that the Magushan granodiorites could be formed by metasomatized mantle-derived magmas, mixing with materials from Neoproterozoic crust that is widely distributed in the Southern Anhui. This study concludes that the formation of the Magushan Cu-Mo polymetallic deposits may largely depend on an oxidizing environment and multi-sources mixed of mantle- and crust-derived materials.
The Partner Does Matter: The Structure of Heteroaggregates of Acridine Orange in Water
Authors: Shenderovich Ilya
Published: August 2019

Self-assembly of organic molecules in aqueous solutions is governed by a delicate entropy/enthalpy balance. Even small changes in their intermolecular interactions can cause critical changes in the structure of the aggregates and their spectral properties. The experimental results reported here demonstrate that protonated cations of acridine orange, acridine, and acridin-9-amine form stable J-heteroaggregates when in water. The structures of these aggregates are justified by the homonuclear 1H cross-relaxation nuclear magnetic resonance (NMR). The absorption and fluorescence of these aggregates deviate characteristically from the known H-homoaggregates of the protonated cations of acridine orange. The latter makes acridine orange a handy optical sensor for soft matter studies.
Floral Scent Variation in the Heterostylous Species Gelsemium sempervirens
Authors: Obi Johnson Bettie , Golonka Annette M. , Blackwell Austin , Vazquez Iver , Wolfram Nigel
Published: August 2019

Gelsemium sempervirens (L.) W.T. Aiton, a distylous woody vine of the family Gelsemiaceae, produces sweetly fragrant flowers that are known for the toxic alkaloids they contain. The composition of this plant’s floral scent has not previously been determined. In this study, the scent profiles of 74 flowers obtained from six different wild and cultivated populations of G. sempervirens were measured by solid phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS). There were 81 volatile organic compounds identified and characterized as benzenoids, terpenoids, fatty acid derivatives, and yeast associated compounds. The most abundant compound was benzaldehyde (23–80%) followed by ethanol (0.9–17%), benzyl benzoate (2–15%), 4-anisaldehyde (2–11%), (Z)-α-ocimene (0–34%), and α-farnesene (0.1–16%). The impacts of geographic location, population type (wild or cultivated), and style morph (L = long, S = short) on scent profile were investigated. The results showed no relationship between geographic location or population type and volatile organic compounds (VOC) profile, but did show a significant scent profile difference between L and S morphs based on non-metric multidimensional scaling (NMDS) using Bray-Curtis similarity indices. The L morphs contained higher amounts of benzenoids and the S morphs contained higher amounts of terpenoids in their scent profiles. The L morphs also produced a higher total abundance of scent compounds than the S morphs. This study represents the first floral scent determination of G. sempervirens finding significant variation in scent abundance and composition between style morphs.
Effects of Halogen, Chalcogen, Pnicogen, and Tetrel Bonds on IR and NMR Spectra
Authors: Lu Jia , Scheiner Steve
Published: August 2019

Complexes were formed pairing FX, FHY, FH2Z, and FH3T (X = Cl, Br, I; Y = S, Se, Te; Z = P, As, Sb; T = Si, Ge, Sn) with NH3 in order to form an A⋯N noncovalent bond, where A refers to the central atom. Geometries, energetics, atomic charges, and spectroscopic characteristics of these complexes were evaluated via DFT calculations. In all cases, the A–F bond, which is located opposite the base and is responsible for the σ-hole on the A atom, elongates and its stretching frequency undergoes a shift to the red. This shift varies from 42 to 175 cm−1 and is largest for the halogen bonds, followed by chalcogen, tetrel, and then pnicogen. The shift also decreases as the central A atom is enlarged. The NMR chemical shielding of the A atom is increased while that of the F and electron donor N atom are lowered. Unlike the IR frequency shifts, it is the third-row A atoms that undergo the largest change in NMR shielding. The change in shielding of A is highly variable, ranging from negligible for FSnH3 all the way up to 1675 ppm for FBr, while those of the F atom lie in the 55–422 ppm range. Although smaller in magnitude, the changes in the N shielding are still easily detectable, between 7 and 27 ppm.
Chemical Composition and Antioxidant Properties of Essential Oils from Peppermint, Native Spearmint and Scotch Spearmint
Authors: Wu Zhaohai , Tan Bie , Liu Yanhong , Dunn James , Martorell Guerola Patricia , Tortajada Marta , Cao Zhijun , Ji Peng
Published: August 2019

Natural antioxidants have drawn growing interest for use in animal feed and the food industry. In the current study, essential oils (EOs) obtained from hydrodistillation of three mentha species, including Mentha piperita (peppermint), Mentha spicata (native spearmint) and Mentha gracilis (Scotch spearmint), harvested in the Midwest region in the United States, were analyzed for their chemical composition using gas chromatography-mass spectrometry, and their antioxidant properties were assessed through chemical assays, in vitro cell culture modeling and in Caenorhabditis elegans (C. elegans). The activity of ferric iron reduction and free-radical scavenging capacity were assessed through chemical-based assays, including the reducing power assay, 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, and Trolox equivalent antioxidant capacity assay (TEAC). Subsequently, the capacity of EOs to mitigate lipid peroxidation was analyzed at various doses using fresh liver homogenates from pigs. A porcine jejunum epithelial cell line (IPEC-J2) was employed as in vitro model to study the cellular antioxidant activity of the mint EOs. Finally, the effectiveness of mint EOs to alleviate acute systemic oxidative damage were evaluated in vivo using C. elegans. Data were analyzed by the MIXED procedure of SAS. Contrast statement was performed to assess linear or quadratic effects of mint EOs given at various doses. All three EOs are mostly composed of monoterpenes and their derivatives (76–90%), but differed in the major compounds, which are menthol and menthone (50%) in peppermint EO and carvone (70%) in spearmint EOs. Three mint EOs demonstrated prominent radical scavenging and Fe3+ reducing activity in chemical-based assays. In comparison with native and Scotch spearmint EOs, peppermint EO had the lowest (p < 0.05) half maximal effective concentration (EC50) in DPPH and TEAC assays and higher efficacy in the reducing power assay. All three EOs exhibited equivalent activity in mitigation of chemical-induced lipid peroxidation in liver tissues in a dose-dependent manner (linear, p < 0.001). The maximal cellular antioxidant activity (CAA) was observed at 5 µg/mL for peppermint, and 100 µg/mL for native and Scotch spearmint EOs. The addition of 25 µg/mL of both spearmint EOs increased (p < 0.05) cellular concentrations of glutathione in H2O2-treated IPEC-J2 cells, suggesting enhanced endogenous antioxidant defense. Supplementation of 100 µg/mL of peppermint or Scotch spearmint EO significantly increased (p < 0.05) the survival rate of C. elegans in response to H2O2-induced oxidative stress. The protective effect is comparable to that of supplementation of 10 µg/mL of ascorbic acid. However native spearmint EO failed to reduce the death rate within the same supplementation dose (10–200 μg/mL).
Real-Time 3D Single Particle Tracking: Towards Active Feedback Single Molecule Spectroscopy in Live Cells
Authors: Hou Shangguo , Johnson Courtney , Welsher Kevin
Published: August 2019

Single molecule fluorescence spectroscopy has been largely implemented using methods which require tethering of molecules to a substrate in order to make high temporal resolution measurements. However, the act of tethering a molecule requires that the molecule be removed from its environment. This is especially perturbative when measuring biomolecules such as enzymes, which may rely on the non-equilibrium and crowded cellular environment for normal function. A method which may be able to un-tether single molecule fluorescence spectroscopy is real-time 3D single particle tracking (RT-3D-SPT). RT-3D-SPT uses active feedback to effectively lock-on to freely diffusing particles so they can be measured continuously with up to photon-limited temporal resolution over large axial ranges. This review gives an overview of the various active feedback 3D single particle tracking methods, highlighting specialized detection and excitation schemes which enable high-speed real-time tracking. Furthermore, the combination of these active feedback methods with simultaneous live-cell imaging is discussed. Finally, the successes in real-time 3D single molecule tracking (RT-3D-SMT) thus far and the roadmap going forward for this promising family of techniques are discussed.
Variability of Bioactive Glucosinolates, Isothiocyanates and Enzyme Patterns in Horseradish Hairy Root Cultures Initiated from Different Organs
Authors: Bertóti Regina , Böszörményi Andrea , Alberti Ágnes , Béni Szabolcs , M-Hamvas Márta , Szőke Éva , Vasas Gábor , Gonda Sándor
Published: August 2019

Horseradish hairy root cultures are suitable plant tissue organs to study the glucosinolate–myrosinase–isothiocyanate system and also to produce the biologically active isothiocyanates and horseradish peroxidase, widely used in molecular biology. Fifty hairy root clones were isolated after Agrobacterium rhizogenes infection of surface sterilized Armoracia rusticana petioles and leaf blades, from which 21 were viable after antibiotic treatment. Biomass properties (e.g., dry weight %, daily growth index), glucosinolate content (analyzed by liquid chromatography-electronspray ionization-mass spectrometry (LC-ESI-MS/MS)), isothiocyanate and nitrile content (analyzed by gas chromatography-mass spectrometry (GC-MS)), myrosinase (on-gel detection) and horseradish peroxidase enzyme patterns (on-gel detection and spectrophotometry), and morphological features were examined with multi-variable statistical analysis. In addition to the several positive and negative correlations, the most outstanding phenomenon was many parameters of the hairy root clones showed dependence on the organ of origin. Among others, the daily growth index, sinigrin, glucobrassicin, 3-phenylpropionitrile, indole-3-acetonitrile and horseradish peroxidase values showed significantly higher levels in horseradish hairy root cultures initiated from leaf blades.
The Kinetic Behaviors of H Impurities in the Li/Ta Bilayer: Application for the Accelerator-Based BNCT
Authors: Liu Xiao , Chen Huaican , Tong Jianfei , He Wenhao , Li Xujing , Liang Tianjiao , Li Yuhong , Yin Wen
Published: August 2019

Hydrogen bubble phenomenon is one of the key issues to be solved in the development of a long-life target system for boron neutron capture therapy (BNCT). In this study, we assessed the kinetic behaviors of H impurities in the nano-composite target from the atomic level. Firstly, two kinds of Li/Ta nanolayer models were constructed, based on the calculated lattice parameters and surface energies. The H solution energy, diffusion mechanism, and hydrogen bubbles formation in the Li/Ta nanostructured bilayer were studied, through theoretical modeling and simulation. Our results show that the Li/Ta interfaces are effective sinks of H atoms because the H solution energies in the interface are lower. Meanwhile, due to the relatively low diffusion barriers, the large-scale H transport through the interface is possible. In addition, although it is more likely to form hydrogen bubbles in the Ta layer, compared with the Li layer, the anti-blistering ability of Ta is more impressive compared with most of other candidate materials. Therefore, the Ta layer is able to act as the hydrogen absorber in the Li/Ta bilayer, and relieve the hydrogen damage of the Li layer in the large-scale proton radiations.
Examining the Efficacy of a ‘Feasible’ Nudge Intervention to Increase the Purchase of Vegetables by First Year University Students (17–19 Years of Age) in British Columbia: A Pilot Study
Authors: Mistura Matheus , Fetterly Nicole , Rhodes Ryan E. , Tomlin Dona , Naylor Patti-Jean
Published: August 2019

In the transition from high school to university, vegetable consumption tends to deteriorate, potentially influencing immediate and longer-term health outcomes. Nudges, manipulation of the environment to influence choice, have emerged as important to behavior change goals. This quasi-experimental pilot study examined the impact of a contextually feasible evidence-informed nudge intervention on food purchasing behavior of older adolescents (1st year students) in a university residence cafeteria in British Columbia, Canada. A co-design process with students and staff identified a student relevant and operationally feasible nudge intervention; a placement nudge, fresh vegetables at the hot food table, combined with a sensory and cognitive nudge, signage encouraging vegetable purchase). Using a 12-week single-case A-B-A-B design, observations of the proportion of vegetables purchased were used to assess intervention efficacy. Data analysis included visual trend inspection, central tendency measures, data overlap, variability and latency. Visual trend inspection showed a positive trend when nudges were in place, which was more apparent with female purchases and during the first intervention (B) phase. However, further analysis showed lack of baseline stability, high variability across phases and overlapping data, limiting efficacy conclusions. Menu choices, staff encouragement, term timing and student finances are other potential influences. Further ‘real world’ nudge research is needed.
Comparison of Target Features for Predicting Drug-Target Interactions by Deep Neural Network Based on Large-Scale Drug-Induced Transcriptome Data
Authors: Lee Hanbi , Kim Wankyu
Published: August 2019

Uncovering drug-target interactions (DTIs) is pivotal to understand drug mode-of-action (MoA), avoid adverse drug reaction (ADR), and seek opportunities for drug repositioning (DR). For decades, in silico predictions for DTIs have largely depended on structural information of both targets and compounds, e.g., docking or ligand-based virtual screening. Recently, the application of deep neural network (DNN) is opening a new path to uncover novel DTIs for thousands of targets. One important question is which features for targets are most relevant to DTI prediction. As an early attempt to answer this question, we objectively compared three canonical target features extracted from: (i) the expression profiles by gene knockdown (GEPs); (ii) the protein–protein interaction network (PPI network); and (iii) the pathway membership (PM) of a target gene. For drug features, the large-scale drug-induced transcriptome dataset, or the Library of Integrated Network-based Cellular Signatures (LINCS) L1000 dataset was used. All these features are closely related to protein function or drug MoA, of which utility is only sparsely investigated. In particular, few studies have compared the three types of target features in DNN-based DTI prediction under the same evaluation scheme. Among the three target features, the PM and the PPI network show similar performances superior to GEPs. DNN models based on both features consistently outperformed other machine learning methods such as naïve Bayes, random forest, or logistic regression.
Evaluation of Tumor-Targeting Properties of an Antagonistic Bombesin Analogue RM26 Conjugated with a Non-Residualizing Radioiodine Label Comparison with a Radiometal-Labelled Counterpart
Authors: Oroujeni Maryam , Abouzayed Ayman , Lundmark Fanny , Mitran Bogdan , Orlova Anna , Tolmachev Vladimir , Rosenström Ulrika
Published: August 2019

Radiolabelled antagonistic bombesin analogues are successfully used for targeting of gastrin-releasing peptide receptors (GRPR) that are overexpressed in prostate cancer. Internalization of antagonistic bombesin analogues is slow. We hypothesized that the use of a non-residualizing radioiodine label might not affect the tumour uptake but would reduce the retention in normal organs, where radiopharmaceutical would be internalized. To test this hypothesis, tyrosine was conjugated via diethylene glycol linker to N-terminus of an antagonistic bombesin analogue RM26 to form Tyr-PEG2-RM26. [111In]In-DOTA-PEG2-RM26 was used as a control with a residualizing label. Tyr-PEG2-RM26 was labelled with 125I with 95% radiochemical purity and retained binding specificity to GRPR. The IC50 values for Tyr-PEG2-RM26 and DOTA-PEG2-RM26 were 1.7 ± 0.3 nM and 3.3 ± 0.5 nM, respectively. The cellular processing of [125I]I-Tyr-PEG2-RM26 by PC-3 cells showed unusually fast internalization. Biodistribution showed that uptake in pancreas and tumour was GRPR-specific for both radioconjugates. Blood clearance of [125I]I-Tyr-PEG2-RM26 was appreciably slower and activity accumulation in all organs was significantly higher than for [111In]In-DOTA-PEG2-RM26. Tumor uptake of [111In]In-DOTA-PEG2-RM26 was significantly higher than for [125I]I-Tyr-PEG2-RM26, resulting in higher tumour-to-organ ratio for [111In]In-DOTA-PEG2-RM26 at studied time points. Incorporation of amino acids with hydrophilic side-chains next to tyrosine might overcome the problems associated with the use of tyrosine as a prosthetic group for radioiodination.
Formulation Strategies for Folate-Targeted Liposomes and Their Biomedical Applications
Authors: Kumar Parveen , Huo Peipei , Liu Bo
Published: August 2019

The folate receptor (FR) is a tumor-associated antigen that can bind with folic acid (FA) and its conjugates with high affinity and ingests the bound molecules inside the cell via the endocytic mechanism. A wide variety of payloads can be delivered to FR-overexpressed cells using folate as the ligand, ranging from small drug molecules to large DNA-containing macromolecules. A broad range of folate attached liposomes have been proven to be highly effective as the targeted delivery system. For the rational design of folate-targeted liposomes, an intense conceptual understanding combining chemical and biomedical points of view is necessary because of the interdisciplinary nature of the field. The fabrication of the folate-conjugated liposomes basically involves the attachment of FA with phospholipids, cholesterol or peptides before liposomal formulation. The present review aims to provide detailed information about the design and fabrication of folate-conjugated liposomes using FA attached uncleavable/cleavable phospholipids, cholesterol or peptides. Advances in the area of folate-targeted liposomes and their biomedical applications have also been discussed.
Pharmacokinetic Evaluation of Metabolic Drug Interactions between Repaglinide and Celecoxib by a Bioanalytical HPLC Method for Their Simultaneous Determination with Fluorescence Detection
Authors: Han Dong-Gyun , Kwak Jinsook , Seo Seong-Wook , Kim Ji-Min , Yoo Jin-Wook , Jung Yunjin , Lee Yun-Hee , Kim Min-Soo , Jung Young-Suk , Yun Hwayoung , Yoon In-Soo
Published: August 2019

Since diabetes mellitus and osteoarthritis are highly prevalent diseases, combinations of antidiabetic agents like repaglinide (REP) and non-steroidal anti-inflammatory drugs (NSAID) like celecoxib (CEL) could be commonly used in clinical practice. In this study, a simple and sensitive bioanalytical HPLC method combined with fluorescence detector (HPLC-FL) was developed and fully validated for simultaneous quantification of REP and CEL. A simple protein precipitation procedure and reversed C18 column with an isocratic mobile phase (mixture of ACN and pH 6.0 phosphate buffer) were employed for sample preparation and chromatographic separation. The fluorescence detector was set at a single excitation/emission wavelength pair of 240 nm/380 nm. The linearity (10–2000 ng/mL), accuracy, precision, extraction recovery, matrix effect, and stability for this method were validated as per the current FDA guidance. The bioanalytical method was applied to study pharmacokinetic interactions between REP and CEL in vivo, successfully showing that concurrent administration with oral REP significantly altered the pharmacokinetics of oral CEL. Furthermore, an in vitro metabolism and protein binding study using human materials highlighted the possibility of metabolism-based interactions between CEL and REP in clinical settings.
Investigation of Dissolution Mechanism and Release Kinetics of Poorly Water-Soluble Tadalafil from Amorphous Solid Dispersions Prepared by Various Methods
Authors: Školáková Tereza , Slámová Michaela , Školáková Andrea , Kadeřábková Alena , Patera Jan , Zámostný Petr
Published: August 2019

The aims of this study were to investigate how the release of tadalafil is influenced by two grades of polyvinylpyrrolidone (Kollidon® 12 PF and Kollidon® VA 64) and various methods of preparing solid dispersions (solvent evaporation, spray drying and hot-melt extrusion). Tadalafil is poorly water-soluble and its high melting point makes it very sensitive to the solid dispersion preparation method. Therefore, the objectives were to make a comparative evaluation among different solid dispersions and to assess the effect of the physicochemical nature of solid dispersions on the drug release profile with respect to the erosion-diffusion mechanism. The solid dispersions were evaluated for dissolution profiles, XRD, SEM, FT-IR, DSC, and solubility or stability studies. It was found that tadalafil release was influenced by polymer molecular weight. Therefore, solid dispersions containing Kollidon® 12 PF showed a faster dissolution rate compared to Kollidon® VA 64. Tadalafil was released from solid dispersions containing Kollidon® 12 PF because of the combination of erosion and diffusion mechanisms. The diffusion mechanisms were predominant in the initial phase of the experiment and the slow erosion was dissolution-controlling at the second stage of the dissolution. On the contrary, the tadalafil release rate from solid dispersions containing Kollidon® VA 64 was controlled solely by the erosion mechanism.
Flow Patterns of Viscoelastic Fracture Fluids in Porous Media: Influence of Pore-Throat Structures
Authors: Yu Xiaoxi , Li Yuan , Liu Yuquan , Yang Yuping , Wu Yining
Published: August 2019

Viscoelastic surfactant (VES) fluid and hydrolyzed polyacryamide (HPAM) solution are two of the most common fracturing fluids used in the hydraulic fracturing development of unconventional reservoirs. The filtration of fracturing fluids in porous media is mainly determined by the flow patterns in pore-throat structures. In this paper, three different microdevices analogue of porous media allow access to a large range of Deborah number (De) and concomitantly low Reynolds number (Re). Continuous pore-throat structures were applied to study the feedback effect of downstream structure on upstream flow of VES fluid and HPAM solution with Deborah (De) number from 1.11 to 146.4. In the infinite straight channel, flow patterns between VES fluids and HPAM solution were similar. However, as pore length shortened to 800 μm, flow field of VES fluid exhibited the triangle shape with double-peaks velocity patterns. The flow field of HPAM solution presented stable and centralized streamlines when Re was larger than 4.29 × 10−2. Additionally, when the pore length was further shortened to 400 μm, double-peaks velocity patterns were vanished for VES fluid and the stable convergent flow characteristic of HPAM solution was observed with all flow rates.
Preparation and Properties of a High-Performance EOEOEA-Based Gel-Polymer-Electrolyte Lithium Battery
Authors: Ding Wenwen , Wei Chun , Wang Shiqi , Zou Linmin , Gong Yongyang , Liu Yuanli , Zang Limin
Published: August 2019

Gel polymer electrolyte (GPE) is a promising candidate for lithium-ion batteries due to its adhesion property (like a solid), diffusion property (like a liquid), and inhibition of the growth of lithium dendrite. In this paper, 2-(2-ethoxyethoxy)ethyl acrylate (EOEOEA) and LiBF4 electrolyte were mixed as precursors of gel polymer electrolytes. Through thermal curing, a thermally stable GPE with high ionic conductivity (5.60 × 10−4 s/cm at 30 °C) and wide room temperature electrochemical window (4.65 V) was prepared, and the properties of the GPE were measured by linear sweep voltammetry (LSV), AC impedance spectroscopy, Thermogravimetric analysis (TG), and X-ray diffraction (XRD) techniques. On the basis of the in-situ deep polymerization on a LiFePO4 electrode and cellulose membrane in a battery case, EOEOEA-based GPE could be derived on both LiFePO4 electrode and cellulose membrane. Meanwhile, the contact between GPE, LiFePO4 electrode, and lithium electrode was promoted. The capacity retention rate of the as-prepared LiBF4-EOEOEA 30% gel lithium battery reached 100% under the condition of 0.1 °C after 50 cycles, and the Coulombic efficiency was over 99%. Meanwhile, the growth of lithium dendrite could be effectively inhibited. GPE can be applied in high-performance lithium batteries.
Preparation of Graft Poly(Arylene Ether Sulfone)s-Based Copolymer with Enhanced Phase-Separated Morphology as Proton Exchange Membranes via Atom Transfer Radical Polymerization
Authors: Zhao Yang , Li Xue , Wang Zhongyang , Xie Xiaofeng , Qian Wei
Published: August 2019

Novel proton exchange membranes (PEMs) based on graft copoly(arylene ether sulfone)s with enhanced phase-separated morphology were prepared using atom transfer radical polymerization (ATRP). A series of PEMs with different graft lengths and sulfonation degrees were prepared. The phase-separated morphologies were confirmed by transmission electron microscopy. Among the membranes prepared and evaluated, PAESPS18S2 exhibited considerably high proton conductivity (0.151 S/cm, 85 °C), benefitting from the graft polymer architecture and phase-separated morphology. The membranes also possessed excellent thermal and chemical stabilities. Highly conductive and stable copoly(arylene ether sulfone)-based membranes would be promising candidates as polymer electrolytes for fuel cell applications.
Preparation of Peelable Coating Films with a Metal Organic Framework (UiO-66) and Self-Crosslinkable Polyurethane for the Decomposition of Methyl Paraoxon
Authors: Long Ngo Hoang , Park Hee-woong , Chae Gyeong-seok , Lee Jung Hyun , Bae Se Won , Shin Seunghan
Published: August 2019

For the fabrication of a peelable coating material that decomposes methyl paraoxone (MPO), a nerve agent simulant, self-crosslinkable waterborne polyurethanes (PUs) containing silane groups at the ends and a metal organic framework (UiO-66) were synthesized. UiO-66 dispersed PU solutions for spray coating were prepared by controlling the amount of silane in PU and the content of UiO-66. PUs with a large amount of silane (more than 7.2 wt.%) were easily gelated by adding UiO-66 because the solution was changed from neutral (pH = 7.3) to strongly acidic (pH = 2.5). Therefore, the silane content in PUs should be carefully controlled for the fabrication of composite films. When UiO-66 was added to the PU with a silane content of 2.7 wt.%, the reinforcing effect by UiO-66 was observed up to 15.3 wt.%, but a further increase in UiO-66 content decreased both the tensile strength and the elongation. The peel strength of the PU composite films on polyethylene (PET) and glass substrates decreased with increasing UiO-66 content, but their MPO conversion increased with increasing UiO-66 content. The PU composite film with 49.5 wt.% of added UiO-66 showed the MPO conversion of 63.2% and was easily peeled off from PET and glass substrates.
Uniform Distribution and Densification of Jets in Needleless Electrospinning Using Annular Tip Nozzle
Authors: Chen Hongbo , Wang Chuansheng , Ali Imdad , Li Haoyi , Chen Xiaoqing , Yang Weimin , Han Wenwen , Liu Haichao , Jiao Dongmei , Yin Fengfu
Published: August 2019

Numerous jets can be generated simultaneously on a nozzle by needleless melt electrospinning technology which has the advantages of solvent-free residues and environmental friendliness; and potential industrial application prospects. In this paper, the linear annular tip nozzle was taken as the research object, and the high-speed image acquisition of the jets generation and distribution process of annular tip nozzle was carried out and compared with that of straight-line tip nozzle. The results showed that the repulsive force between the jets caused a slight adjustment in the position of the jets on the free surface, the force between the jets on the annular closed curve canceled each other and eventually reached the equilibrium state, making the position of the jets stable and the distance between the jets the same, and the distance between the jets was related to the intensity of the induced electric field at the tip of the nozzle. Relevant conclusions can provide scientific and practical guidance for the design of needleless electrospinning nozzles on free surface in order to achieve uniform and efficient preparation of ultrafine fibers.
Integration of Ground-Based Remote-Sensing and In Situ Multidisciplinary Monitoring Data to Analyze the Eruptive Activity of Stromboli Volcano in 2017–2018
Authors: Giudicepietro Flora , Calvari Sonia , Alparone Salvatore , Bianco Francesca , Bonaccorso Alessandro , Bruno Valentina , Caputo Teresa , Cristaldi Antonio , D’Auria Luca , De Cesare Walter , Di Lieto Bellina , Esposito Antonietta M. , Gambino Salvatore , Inguaggiato Salvatore , Macedonio Giovanni , Martini Marcello , Mattia Mario , Orazi Massimo , Paonita Antonio , Peluso Rosario , Privitera Eugenio , Romano Pierdomenico , Scarpato Giovanni , Tramelli Anna , Vita Fabio
Published: August 2019

After a period of mild eruptive activity, Stromboli showed between 2017 and 2018 a reawakening phase, with an increase in the eruptive activity starting in May 2017. The alert level of the volcano was raised from “green” (base) to “yellow” (attention) on 7 December 2017, and a small lava overflowed the crater rim on 15 December 2017. Between July 2017 and August 2018 the monitoring networks recorded nine major explosions, which are a serious hazard for Stromboli because they affect the summit area, crowded by tourists. We studied the 2017–2018 eruptive phase through the analysis of multidisciplinary data comprising thermal video-camera images, seismic, geodetic and geochemical data. We focused on the major explosion mechanism analyzing the well-recorded 1 December 2017 major explosion as a case study. We found that the 2017–2018 eruptive phase is consistent with a greater gas-rich magma supply in the shallow system. Furthermore, through the analysis of the case study major explosion, we identified precursory phases in the strainmeter and seismic data occurring 77 and 38 s before the explosive jet reached the eruptive vent, respectively. On the basis of these short-term precursors, we propose an automatic timely alarm system for major explosions at Stromboli volcano.
Super-Resolution Land Cover Mapping Based on the Convolutional Neural Network
Authors: Jia Yuanxin , Ge Yong , Chen Yuehong , Li Sanping , Heuvelink Gerard B.M. , Ling Feng
Published: August 2019

Super-resolution mapping (SRM) is used to obtain fine-scale land cover maps from coarse remote sensing images. Spatial attraction, geostatistics, and using prior geographic information are conventional approaches used to derive fine-scale land cover maps. As the convolutional neural network (CNN) has been shown to be effective in capturing the spatial characteristics of geographic objects and extrapolating calibrated methods to other study areas, it may be a useful approach to overcome limitations of current SRM methods. In this paper, a new SRM method based on the CNN ( SRM CNN ) is proposed and tested. Specifically, an encoder-decoder CNN is used to model the nonlinear relationship between coarse remote sensing images and fine-scale land cover maps. Two real-image experiments were conducted to analyze the effectiveness of the proposed method. The results demonstrate that the overall accuracy of the proposed SRM CNN method was 3% to 5% higher than that of two existing SRM methods. Moreover, the proposed SRM CNN method was validated by visualizing output features and analyzing the performance of different geographic objects.
Estimation and Efficient Utilization of Straw Resources in Ghana
Authors: Seglah Patience Afi , Wang Yajing , Wang Hongyan , Bi Yuyun
Published: August 2019

The significance of this research is on maize, rice, sorghum, millet, groundnut, soybeans and cowpea straw for stronger sustainability in Ghana’s economic development. Quantifying and re-use of crop straw resources in Ghana is still at the infancy stage hampering the efficient recycling of these resources in a sustainable manner. Sustainability is straw as a renewable resource to improve soils, livestock production, generate renewable energy and reduce pollution for development. The aim of this research was to estimate the crop straw yield from 2006 to 2016 and identify the various utilization modes for major cereals and legumes in Ghana. In addition the distribution of maize, rice, sorghum and cowpea straw across major producing regions was calculated. Results obtained showed that 77,404,709.75 tonnes of cereals and legumes straw were produced in Ghana from 2006 to 2016. Cereal straw recorded a 72.3% yield whilst legume straw recorded 26.8%. Maize and groundnut straw recorded the highest yield of 37,323,264.16 and 12,495,288.96 tonnes respectively. Brong Ahafo region of Ghana had the highest maize straw yield with the Northern region recording readily availability of both cereals and legumes straw resources. The major re-use methods of straw in Ghana are as livestock feed, fertilizer, cooking fuel, for sale and as a substrate for mushroom production. We recommend strategies the government can adapt to develop policies geared towards the accurate recording of straw and their comprehensive utilization in Ghana. The efficient utilization of straw resources will reduce soil erosion, improve soil fertility, serve as feed for livestock, reduce pollution, generate biofuels plus generate employment to benefit the rural economy.
Household Barriers to Climate Change Action: Perspectives from Nuevo Leon, Mexico
Authors: González-Hernández D. Liliana , Meijles Erik W. , Vanclay Frank
Published: August 2019

It is necessary to mobilize households so that they make changes to their everyday activities to address climate change. However, in the academic literature, there has been little focus on the perceived barriers to climate change action at the household level. Previous research has also highlighted a need for more studies in Latin America. This study contributes to the literature by filling these gaps. In a face-to-face and online survey administered in Nuevo Leon, Mexico, we asked participants what barriers impede their household from taking action to address climate change. Using thematic analysis, seven main barriers were identified: (i) everyday life; (ii) awareness of climate change; (iii) lack of perceived locus of control; (iv) physical limitations of the dwelling; (v) social, (vi) regulatory; and (vii) economic. Given the significant potential effects of climate change in the Nuevo Leon region, a better understanding of the barriers that prevent households from addressing climate change will inform the development of targeted guidelines and strategies to address changing climate.
The Importance of Standardised Data-Collection Methods in the Improvement of Thermal Comfort Assessment Models for Developing Countries in the Tropics
Authors: Rodriguez Carolina , Coronado María , D’Alessandro Marta , Medina Juan
Published: August 2019

Thermal comfort in the built environment is one of the most defining parameters influencing energy use, environmental quality, and occupant satisfaction. Unfortunately, there is a lack of research in this area within developing countries, which are becoming increasingly urbanised and where mechanical air conditioning demands are rising. Many of these countries are adopting thermal comfort standards such as the ASHRAE Standard 55, the EN 15251, and the ISO 7730 to regulate the use of air-conditioning; even when these standards have been widely criticised for their inadequacy within geographical regions different to the ones that they were designed for. Research suggests the need to confirm these models through further post-occupancy studies and fieldwork. Deficiencies in data collection and methodologies are thought to require particular attention to develop algorithms that can predict thermal comfort levels accurately. Comprehensive strategies considering interrelated psychological, physiological and social factors are needed. This manuscript highlights gaps of research, specifically within tropical developing countries, through the analysis of Colombia as a case study. It emphasises the importance of standardised fieldwork data and gives examples of alternative collection systems. This aims to contribute to the understanding of occupant´s adaptive behaviours and their impact on the mitigation of climate change.
Influence of Surface Treatment of Recycled Aggregates on Mechanical Properties and Bond Strength of Self-Compacting Concrete
Authors: Tang Waiching , Khavarian Mehrnoush , Yousefi Ali , Chan Ricky W. K. , Cui Hongzhi
Published: August 2019

In the last decade there has been a massive growth for development of concrete infrastructures all around the world. Take into account environmental concerns, concrete technology should direct efforts toward assuring development and fabrication of sustainable and resilient concrete. For this purpose, incorporation of recycled concrete aggregate in concrete products particularly self-compacting concrete (SCC) for structural and non-structural application would be significant achievement. In this study the fresh and hardened properties of SCC prepared by substituting natural aggregates (NA) with recycled coarse aggregates (RCA). In addition, bonding behaviour of reinforced RCA-SCC for structural application was investigated. Moreover, surface treatment of RCA using lithium silicate solution was proposed to investigate its feasibility to improve the fresh and hardened properties of SCC as well as its bonding strength. The mechanical properties including compressive strength, tensile strength and elastic modulus of SCC mixes using untreated RCA and treated RCA (TRCA) were investigated. The results showed an improvement in performance of SCC mixes made with TRCA in compare with the untreated samples. The bond behaviour between SCC made with RCA and steel reinforcement was studied and the relationship between the brittleness and bonding of SCC mixes using untreated RCA and TRCA determined. The effect of surface treatment on the interfacial transition zone (ITZ) between adhered mortar and RCA studied using scanning electron microscope (SEM). It was determined that the treatment of RCA improved the bond at the ITZ through densification. The results gave experimental evidence of the suitability of RCA-SCC for structural use and application in reinforced concrete.