bluuebunny/crossref_metadata_2025 huggingface dataset:
Hydrogen Effect on the Cyclic Behavior of a Superelastic NiTi Archwire
Authors: Sarraj Rihem , Kessentini Amir , Hassine Tarek , Algahtani Ali , Gamaoun Fehmi
Published: March 2019

In this work, we are interested in examining the strain rate effect on the mechanical behavior of Ni–Ti superelastic wires after hydrogen charging and ageing for 24 h. Specimens underwent 50 cycles of loading-unloading, reaching an imposed deformation of 7.6%. During loading, strain rates from 10−4 s−1 to 10−2 s−1 were achieved. With a strain rate of 10−2 s−1, the specimens were charged by hydrogen for 6 h and aged for one day showed a superelastic behavior marked by an increase in the residual deformation as a function of the number of cycles. In contrast, after a few number of cycles with a strain rate of 10−4 s−1, the Ni-Ti alloy archwire specimens fractured in a brittle manner during the martensite transformation stage. The thermal desorption analysis showed that, for immersed specimens, the desorption peak of hydrogen appeared at 320 °C. However, after annealing the charged specimens by hydrogen at 400 °C for 1 h, an embrittlement took place at the last cycles for the lower strain rates of 10−4 s−1. The present study suggests that the embrittlement can be due to the development of an internal stress in the subsurface of the parent phase during hydrogen charging and due to the creation of cracks and local zones of plasticity after desorption.
Dynamic Modeling of the Multiring Disk Resonator Gyroscope
Authors: Li Qingsong , Xiao Dingbang , Zhou Xin , Hou Zhanqiang , Zhuo Ming , Xu Yi , Wu Xuezhong
Published: March 2019

The multiring disk resonator gyroscope (DRG) has been a candidate for high performance gyroscopes, however nowadays the finite element method (FEM) is the main method for its analysis due to its complex structure. In this paper we propose a new method to mathematically model the DRG for its vibrating modes and lumped parameters based on the component mode synthesis (CMS) method. Firstly, the natural frequencies and the associated mode shapes of the DRG are mathematically modeled and a comparison with the FEM results is conducted. It shows that the mode shapes of DRG obtained by FEM and mathematical modeling are identical and in the full ranges of geometrical parameters, natural frequency error of the simulation, and calculation results are limited in ±15%. It demonstrates the effectivity and feasibility of the mathematical modeling method. Then, based on the calculated natural frequencies and mode shapes, the lumped mass-spring model of the DRG and effects of geometry parameters on the lumped mass-spring parameters are investigated, which can be used on the design of the DRG. This mathematical modeling method can effectively improve the analyzing efficiency of the DRG and the method can also be used on the analysis of other complex multiring-type resonators.
Establishment of Listeria monocytogenes in the Gastrointestinal Tract
Authors: Davis Morgan L. , Ricke Steven C. , Donaldson Janet R.
Published: March 2019

Listeria monocytogenes is a Gram positive foodborne pathogen that can colonize the gastrointestinal tract of a number of hosts, including humans. These environments contain numerous stressors such as bile, low oxygen and acidic pH, which may impact the level of colonization and persistence of this organism within the GI tract. The ability of L. monocytogenes to establish infections and colonize the gastrointestinal tract is directly related to its ability to overcome these stressors, which is mediated by the efficient expression of several stress response mechanisms during its passage. This review will focus upon how and when this occurs and how this impacts the outcome of foodborne disease.
Mineral Transformations in Gold–(Silver) Tellurides in the Presence of Fluids: Nature and Experiment
Authors: Zhao Jing , Pring Allan
Published: March 2019

Gold–(silver) telluride minerals constitute a major part of the gold endowment at a number of important deposits across the globe. A brief overview of the chemistry and structure of the main gold and silver telluride minerals is presented, focusing on the relationships between calaverite, krennerite, and sylvanite, which have overlapping compositions. These three minerals are replaced by gold–silver alloys when subjected to the actions of hydrothermal fluids under mild hydrothermal conditions (≤220 °C). An overview of the product textures, reaction mechanisms, and kinetics of the oxidative leaching of tellurium from gold–(silver) tellurides is presented. For calaverite and krennerite, the replacement reactions are relatively simple interface-coupled dissolution-reprecipitation reactions. In these reactions, the telluride minerals dissolve at the reaction interface and gold immediately precipitates and grows as gold filaments; the tellurium is oxidized to Te(IV) and is lost to the bulk solution. The replacement of sylvanite is more complex and involves two competing pathways leading to either a gold spongy alloy or a mixture of calaverite, hessite, and petzite. This work highlights the substantial progress that has been made in recent years towards understanding the mineralization processes of natural gold–(silver) telluride minerals and mustard gold under hydrothermal conditions. The results of these studies have potential implications for the industrial treatment of gold-bearing telluride minerals.
Radioactivity of Five Typical General Industrial Solid Wastes and its Influence in Solid Waste Recycling
Authors: Shen Zhihui , Zhang Qin , Cheng Wei , Chen Qianlin
Published: March 2019

The level of radionuclides is an important index for the preparation of building materials from industrial solid waste. In order to investigate the radiological hazard of five kinds of typical general industrial solid wastes in Guizhou, China, including fly ash (FA), red mud (RM), phosphorus slag (PS), phosphogypsum (PG), and electrolytic manganese residue (EMR), the radiation intensity and associated radiological impact were studied. The results show that concentrations of 238U, 235U, 232Th, 226Ra, 210Pb, and 40K for different samples vary widely. The concentration of 238U was both positively correlated with 235U and 226Ra, and the uranium contents in the measured samples were all of natural origin. The radiation levels of PG, EMR, EMR-Na (EMR activated by NaOH), and EMR-Ca (EMR activated by Ca(OH)2) were all lower than the Chinese and the world’s recommended highest levels for materials allowed to be directly used as building materials. The values of the internal and external illumination index (IRa and Iγ, respectively) for FA and RM were higher (IRa > 1.0 and Iγ > 1.3 for FA, IRa > 2.0 and Iγ > 2.0 for RM). The radium equivalent activity (Raeq), indoor and outdoor absorbed dose (Din and Dout, respectively), and corresponding annual effective dose rate (Ein and Eout) of RM, PS, and FA were higher than the recommended limit values (i.e., 370 Bq/kg, 84 nGy/h, 59 nGy/h, 0.4 mSv/y, and 0.07 mSv/y, respectively), resulting from the higher relative contribution of 226Ra and 232Th. The portion of RM, FA, and PS in building materials should be less than 75.44%, 29.72%, and 66.01%, respectively. This study provides quantitative analysis for the safe utilization of FA, RM, PS, PG, and EMR in Guizhou building materials.
Enhancing the Yield of Bioactive Compounds from Sclerocarya birrea Bark by Green Extraction Approaches
Authors: Cádiz-Gurrea María de la Luz , Lozano-Sánchez Jesús , Fernández-Ochoa Álvaro , Segura-Carretero Antonio
Published: March 2019

Sclerocarya birrea is a tree indigenous to Southern Africa with significant importance in rural livelihoods for food, medicine, and carving. The bark, which contains 10–20% tannin, provides several pharmacological benefits as an antidiabetic, anti-inflammatory, antimicrobial, anti-atherogenic, and antioxidant medication, among others. This study compared different extraction techniques used to recover bioactive compounds from marula bark. For this purpose, solid–liquid extraction, supercritical fluid extraction (SFE), and pressurized liquid extraction (PLE) were performed under selected conditions, using only “food-grade” solvents. The potential use of the proposed extraction methodologies was evaluated in term of yield, and the individual phenolic composition determined by HPLC–ESI–TOF–MS. PLE provided a high extraction yield in all experimental conditions. With regard to bioactive compounds composition, a total of 71 compounds, a significant percentage of which in a galloyl form, were distributed in five major categories. The largest number of compounds, mostly flavonoid aglycones, were extracted by PLE, generally when the extraction was developed at low temperatures. SFE did prove effective as a way of extracting antidiabetic proanthocyanidins. Advanced extraction techniques represent a powerful tool to obtain bioactive compounds from S. birrea bark, which can be used as supplements or food ingredients, promoting the valorization of this crop.
Consequences of IDH1/2 Mutations in Gliomas and an Assessment of Inhibitors Targeting Mutated IDH Proteins
Authors: Kaminska Bozena , Czapski Bartosz , Guzik Rafal , Król Sylwia Katarzyna , Gielniewski Bartlomiej
Published: March 2019

Isocitrate dehydrogenases (IDH) 1 and 2 are key metabolic enzymes that generate reduced nicotinamide adenine dinucleotide phosphate (NADPH) to maintain a pool of reduced glutathione and peroxiredoxin, and produce α-ketoglutarate, a co-factor of numerous enzymes. IDH1/2 is mutated in ~70–80% of lower-grade gliomas and the majority of secondary glioblastomas. The mutant IDH1 (R132H), in addition to losing its normal catalytic activity, gains the function of producing the d-(R)-2-hydroxyglutarate (2-HG). Overproduction of 2-HG in cancer cells interferes with cellular metabolism and inhibits histone and DNA demethylases, which results in histone and DNA hypermethylation and the blockade of cellular differentiation. We summarize recent findings characterizing molecular mechanisms underlying oncogenic alterations associated with mutated IDH1/2, and their impact on tumor microenvironment and antitumor immunity. Isoform-selective IDH inhibitors which suppress 2-HG production and induce antitumor responses in cells with IDH1 and IDH2 mutations were developed and validated in preclinical settings. Inhibitors of mutated IDH1/2 enzymes entered clinical trials and represent a novel drug class for targeted therapy of gliomas. We describe the development of small-molecule compounds and peptide vaccines targeting IDH-mutant gliomas and the results of their testing in preclinical and clinical studies. All those results support the translational potential of strategies targeting gliomas carrying IDH1 mutations.
RETRACTED: Huo et al. Protective Effect of Glycyrrhizic Acid on Alcoholic Liver Injury in Rats by Modulating Lipid Metabolism. Molecules 2018, 23, 1623
Authors: Huo Xiaowei , Yang Sa , Sun Xiaoke , Meng Xiangbo , Zhao Yanyan
Published: March 2019

As the authors of the title paper [...]
Green Methodologies for Copper(I)-Catalyzed Azide-Alkyne Cycloadditions: A Comparative Study
Authors: Trujillo Marissa , Hull-Crew Clayton , Outlaw Andrew , Stewart Kevin , Taylor Loren , George Laura , Duensing Allison , Tracey Breanna , Schoffstall Allen
Published: March 2019

Successful copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC) reactions may be achieved by several methods. In this paper, four synthetic protocols were performed for direct comparison of time required for the synthesis, yield, and purity of the 1H-1,2,3-triazole products. The methods with Cu(I) catalysts were conventional, microwave heating, solvent-free, and a method using glycerol solvent. The compounds synthesized in this paper were known non-fluorinated triazoles and new fluorinated triazoles. The results lead to the conclusion that the microwave method should be strongly considered for CuAAC syntheses.
Enhanced Supercapacitor Performance Based on CoAl Layered Double Hydroxide-Polyaniline Hybrid Electrodes Manufactured Using Hydrothermal-Electrodeposition Technology
Authors: Yang Guoshen , Takei Takahiro , Yanagida Sayaka , Kumada Nobuhiro
Published: March 2019

Electrodes with nanosheet architectures can offer the possibility to achieve enhanced energy storage performance. Herein, we have designed and synthesized novel nanosheet structures of CoAl layered double hydroxide (LDH)-polyaniline (PANI) nanocomposite thin films by a hydrothermal-electrodeposition method. The molecular structure, crystal structure, morphology and chemical composition of the composites were characterized by FT-IR, XRD (SXRD), FESEM, and XPS, whereas their electrochemical properties were evaluated by cyclic voltammetry, electrochemical impedance spectroscopy and galvanostatic charge-discharge tests. Compared with the unmodified CoAl LDH, the CoAl LDH-PANI exhibits significantly improved the specific capacitance and cyclic stability. The composite exhibits a high specific capacitance of 528 F/g at a current density of 10 A/g and excellent cyclic stability with an increase of the specific capacitance of 42.7% after 6000 cycle tests. We revealed the degradation behavior of PANI in 1 M KOH/KCl electrolyte, and the active degradation products also further increased the total specific capacitance of the composite. The enhanced electrochemical performance of the nanocomposite can be attributed to its well-designed nanostructure and the synergistic effects of each component. By analyzing the band structure and density of states of CoAl LDH and PANI, we proposed the possible mechanism of synergistic effect in a new perspective.
Determination of Antioxidant Capacity, Phenolics and Volatile Maillard Reaction Products in Rye-Buckwheat Biscuits Supplemented with 3β-d-Rutinoside
Authors: Starowicz Małgorzata , Koutsidis Georgios , Zieliński Henryk
Published: March 2019

The Maillard reaction (MR) is responsible for the development of color, taste and aroma in bakery products though the formation of numerous aroma compounds such as pyrazines, pyrroles and aldehydes, nonvolatile taste active compounds and melanoidins. In this article, we investigate the effect of quercetin 3β-D-rutinoside (rutin) supplementation, at the level of 5–50 mg per 100 g, of rye-buckwheat biscuits on the formation of phenolics and volatile Maillard reaction products (MRPs) such as pyrazines, furfuryl alcohol and furfural, determined by headspace solid phase microextraction followed by gas chromatography–mass spectrometry (HS-SPME/GC–MS), in addition to the effect on the antioxidant capacity. The study confirmed that rutin was stable under baking conditions as showed by its content in rye-buckwheat biscuits. Supplementation of biscuits with increasing amounts of rutin resulted in the progressive increase of total phenolics and antioxidant capacity measured by DPPH and OxHLIA assays, but it had no effect on their sensory quality. From the eighteen compounds identified by HS-SPME/GC–MS in the volatile fraction of biscuits were quantitated as a compounds-of-interest: methylpyrazine, ethylpyrazine, 2,3-; 2,5- and 2,6-dimethylpyrazines, as well as furfural, furfuryl alcohol and hexanal. The rutin supplementation of biscuits might be one of the factors to influence the formation of both desirable volatile compounds and undesirable toxic compounds. In conclusion, this study indicates for the significant role of polyphenols on the formation of volatile compounds in biscuits with possible future application in the development of healthy bakery products with high antioxidant capacity.
Hydrodistillation Extraction Kinetics Regression Models for Essential Oil Yield and Composition in Juniperus virginiana, J. excelsa, and J. sabina
Authors: B. Semerdjieva Ivanka , Shiwakoti Santosh , L. Cantrell Charles , D. Zheljazkov Valtcho , Astatkie Tess , Schlegel Vicki , Radoukova Tzenka
Published: March 2019

The chemical profile and antioxidant capacity of Juniperus virginiana, J. excelsa, and J. sabina essential oil (EO) fractions as a function of time was the subject of this study. The hypothesis was that, capturing EO in sequential timeframes during hydrodistillation would generate fractions containing unique compositions and antioxidant capacity. In J. virginiana, the highest limonene (43%) was found in the 0–5 min oil fraction, with safrole (37%) being highest in the 10–20 and 20–40 min fractions, and elemol (34%) being highest in the 160–240 min fraction. In J. excelsa, α-pinene (34-36%) was the highest in the 0–5 min fraction and in the control (non-stop 0–240 min distillation) oil, limonene (39%) was the highest in the 0–10 min fractions and cedrol (50-53%) was the highest in the 40–240 min fractions. In J. sabina, sabinene (80%) was highest in the 0–3 min fraction. The highest antioxidant capacity of J. virginiana was demonstrated by the 5–10 min fraction; the one in J. sabina by the 3–10 min fraction; and, the one in J. excelsa, by the control. The kinetics regression models that were developed can predict EO composition of the three juniper species eluted at different timeframes. Various industries could benefit from the results from this study.
Green and Facile Assembly of Diverse Fused N-Heterocycles Using Gold-Catalyzed Cascade Reactions in Water
Authors: Jia Xiuwen , Li Pinyi , Liu Xiaoyan , Lin Jiafu , Chu Yiwen , Yu Jinhai , Wang Jiang , Liu Hong , Zhao Fei
Published: March 2019

The present study describes an AuPPh3Cl/AgSbF6-catalyzed cascade reaction between amine nucleophiles and alkynoic acids in water. This process proceeds in high step economy with water as the sole coproduct, and leads to the generation of two rings, together with the formation of three new bonds in a single operation. This green cascade process exhibits valuable features such as low catalyst loading, good to excellent yields, high efficiency in bond formation, excellent selectivity, great tolerance of functional groups, and extraordinarily broad substrate scope. In addition, this is the first example of the generation of an indole/thiophene/pyrrole/pyridine/naphthalene/benzene-fused N-heterocycle library through gold catalysis in water from readily available materials. Notably, the discovery of antibacterial molecules from this library demonstrates its high quality and potential for the identification of active pharmaceutical ingredients.
Let’s Play a Game! Kin-LDD: A Tool for Assisting in the Diagnosis of Children with Learning Difficulties
Authors: Chatzidaki Eleni , Xenos Michalis , Machaira Charikleia
Published: March 2019

This paper presents an alternative approach for the diagnosis of learning difficulties in children. A game-based evaluation study, using Kinaesthetic Learning Difficulties Diagnosis (Kin-LDD), was performed during the actual diagnosis procedure for the identification of learning difficulties. Kin-LDD is a serious game that provides a gesture-based interface and incorporates spatial and time orientation activities. These activities assess children’s cognitive attributes while they are using their motor skills to interact with the game. The aim of this work was to introduce the fun parameter to the diagnostic process, provide a useful tool for the special educators and investigate potential correlations between in-game metrics and the diagnosis outcome. An experiment was conducted in which 30 children played the game during their official assessment for the diagnosis of learning difficulties at the Center for Differential Diagnosis, Diagnosis and Support. Performance metrics were collected automatically while the children were playing the game. These metrics, along with questionnaires appropriate for children and post-session interviews were later analyzed and the findings are presented in the paper. According to the results: (a) children evaluated the game as a fun experience, (b) special educators claimed it was helpful to the diagnostic procedure, and (c) there were statistically significant correlations between in-game metrics and the category of learning difficulty the child was characterized with.
Photocatalytic and Photo-Fenton Catalytic Degradation Activities of Z-Scheme Ag2S/BiFeO3 Heterojunction Composites under Visible-Light Irradiation
Authors: Di Lijing , Yang Hua , Xian Tao , Liu Xueqin , Chen Xiujuan
Published: March 2019

Z-scheme Ag2S/BiFeO3 heterojunction composites were successfully prepared through a precipitation method. The morphology and microstructure characterization demonstrate that Ag2S nanoparticles (30–50 nm) are well-decorated on the surfaces of polyhedral BiFeO3 particles (500–800 nm) to form Ag2S/BiFeO3 heterojunctions. The photocatalytic and photo-Fenton catalytic activities of the as-derived Ag2S/BiFeO3 heterojunction composites were evaluated by the degradation of methyl orange (MO) under visible-light irradiation. The photocatalytic result indicates that the Ag2S/BiFeO3 composites exhibit much improved photocatalytic activities when compared with bare Ag2S and BiFeO3. The optimum composite sample was observed to be 15% Ag2S/BiFeO3 with an Ag2S mass fraction of 15%. Furthermore, the addition of H2O2 can further enhance the dye degradation efficiency, which is due to the synergistic effects of photo- and Fenton catalysis. The results of photoelectrochemical and photoluminescence measurements suggest a greater separation of the photoexcited electron/hole pairs in the Ag2S/BiFeO3 composites. According to the active species trapping experiments, the photocatalytic and photo-Fenton catalytic mechanisms of the Ag2S/BiFeO3 composites were proposed and discussed.
Biopolymers for Biomedical and Pharmaceutical Applications: Recent Advances and Overview of Alginate Electrospinning
Authors: Wróblewska-Krepsztul Jolanta , Rydzkowski Tomasz , Michalska-Pożoga Iwona , Thakur Vijay Kumar
Published: March 2019

Innovative solutions using biopolymer-based materials made of several constituents seems to be particularly attractive for packaging in biomedical and pharmaceutical applications. In this direction, some progress has been made in extending use of the electrospinning process towards fiber formation based on biopolymers and organic compounds for the preparation of novel packaging materials. Electrospinning can be used to create nanofiber mats characterized by high purity of the material, which can be used to create active and modern biomedical and pharmaceutical packaging. Intelligent medical and biomedical packaging with the use of polymers is a broadly and rapidly growing field of interest for industries and academia. Among various polymers, alginate has found many applications in the food sector, biomedicine, and packaging. For example, in drug delivery systems, a mesh made of nanofibres produced by the electrospinning method is highly desired. Electrospinning for biomedicine is based on the use of biopolymers and natural substances, along with the combination of drugs (such as naproxen, sulfikoxazol) and essential oils with antibacterial properties (such as tocopherol, eugenol). This is a striking method due to the ability of producing nanoscale materials and structures of exceptional quality, allowing the substances to be encapsulated and the drugs/biologically active substances placed on polymer nanofibers. So, in this article we briefly summarize the recent advances on electrospinning of biopolymers with particular emphasis on usage of Alginate for biomedical and pharmaceutical applications.
A HfO2/SiTe Based Dual-Layer Selector Device with Minor Threshold Voltage Variation
Authors: Song Bing , Cao Rongrong , Xu Hui , Liu Sen , Liu Haijun , Li Qingjiang
Published: March 2019

Volatile programmable metallization cell is a promising threshold switching selector with excellent characteristics and simple structures. However, the large variation of threshold voltage is a major problem for practical application. In this work, we propose a dual-layer structure to increase selectivity and improve the threshold voltage variation. Compared to single-layer devices, this dual-layer device exhibits higher selectivity (>107) and better threshold voltage uniformity with less than 5% fluctuation during 200 DC switching. The improvement is attributed to good control on the location of the filament formation and rupture after introducing a HfO2 layer. It is deduced that a major factor consists of the difference of Ag ions mobility between SiTe and HfO2 due to the grain boundary quantity.
Effect of Metal Ions on Hybrid Graphite-Diamond Nanowire Growth: Conductivity Measurements from a Single Nanowire Device
Authors: Shellaiah Muthaiah , Chen Ying-Chou , Simon Turibius , Li Liang-Chen , Sun Kien , Ko Fu-Hsiang
Published: March 2019

Novel Cd2+ ions mediated reproducible hybrid graphite-diamond nanowire (G-DNWs; Cd2+-NDS1 NW) growth from 4-Amino-5-phenyl-4H-1,2,4-triazole-3-thiol (S1) functionalized diamond nanoparticles (NDS1) via supramolecular assembly is reported and demonstrated through TEM and AFM images. FTIR, EDX and XPS studies reveal the supramolecular coordination between functional units of NDS1 and Cd2+ ions towards NWs growth. Investigations of XPS, XRD and Raman data show the covering of graphite sheath over DNWs. Moreover, HR-TEM studies on Cd2+-NDS1 NW confirm the coexistence of less perfect sp2 graphite layer and sp3 diamond carbon along with impurity channels and flatten surface morphology. Possible mechanisms behind the G-DNWs growth are proposed and clarified. Subsequently, conductivity of the as-grown G-DNWs is determined through the fabrication of a single Cd2+-NDS1 NW device, in which the G-DNW portion L2 demonstrates a better conductivity of 2.31 × 10−4 mS/cm. In addition, we investigate the temperature-dependent carrier transport mechanisms and the corresponding activation energy in details. Finally, comparisons in electrical resistivities with other carbon-based materials are made to validate the importance of our conductivity measurements.
Room Temperature Resonant Photocurrent in an Erbium Low-Doped Silicon Transistor at Telecom Wavelength
Authors: Celebrano Michele , Ghirardini Lavinia , Finazzi Marco , Ferrari Giorgio , Chiba Yuki , Abdelghafar Ayman , Yano Maasa , Shinada Takahiro , Tanii Takashi , Prati Enrico
Published: March 2019

An erbium-doped silicon transistor prepared by ion implantation and co-doped with oxygen is investigated by photocurrent generation in the telecommunication range. The photocurrent is explored at room temperature as a function of the wavelength by using a supercontinuum laser source working in the μW range. The 1-μm2 transistor is tuned to involve in the transport only those electrons lying in the Er-O states. The spectrally resolved photocurrent is characterized by the typical absorption line of erbium and the linear dependence of the signal over the impinging power demonstrates that the Er-doped transistor is operating far from saturation. The relatively small number of estimated photoexcited atoms (≈ 4 × 10 4 ) makes Er-dpoed silicon potentially suitable for designing resonance-based frequency selective single photon detectors at 1550 nm.
Nutritional Intake and the Risk for Non-Alcoholic Fatty Liver Disease (NAFLD)
Authors: Schattenberg Jörn M. , Bergheim Ina
Published: March 2019

The prevalence of non-alcoholic fatty liver disease (NAFLD) is rising worldwide, and it is estimated that approximately one billion individuals may be afflicted with NAFLD globally [...]
Profiling the Abiotic Stress Responsive microRNA Landscape of Arabidopsis thaliana
Authors: Pegler Joseph L. , Oultram Jackson M. J. , Grof Christopher P. L. , Eamens Andrew L.
Published: March 2019

It is well established among interdisciplinary researchers that there is an urgent need to address the negative impacts that accompany climate change. One such negative impact is the increased prevalence of unfavorable environmental conditions that significantly contribute to reduced agricultural yield. Plant microRNAs (miRNAs) are key gene expression regulators that control development, defense against invading pathogens and adaptation to abiotic stress. Arabidopsis thaliana (Arabidopsis) can be readily molecularly manipulated, therefore offering an excellent experimental system to alter the profile of abiotic stress responsive miRNA/target gene expression modules to determine whether such modification enables Arabidopsis to express an altered abiotic stress response phenotype. Towards this goal, high throughput sequencing was used to profile the miRNA landscape of Arabidopsis whole seedlings exposed to heat, drought and salt stress, and identified 121, 123 and 118 miRNAs with a greater than 2-fold altered abundance, respectively. Quantitative reverse transcriptase polymerase chain reaction (RT-qPCR) was next employed to experimentally validate miRNA abundance fold changes, and to document reciprocal expression trends for the target genes of miRNAs determined abiotic stress responsive. RT-qPCR also demonstrated that each miRNA/target gene expression module determined to be abiotic stress responsive in Arabidopsis whole seedlings was reflective of altered miRNA/target gene abundance in Arabidopsis root and shoot tissues post salt stress exposure. Taken together, the data presented here offers an excellent starting platform to identify the miRNA/target gene expression modules for future molecular manipulation to generate plant lines that display an altered response phenotype to abiotic stress.
Ginger and Turmeric Essential Oils for Weed Control and Food Crop Protection
Authors: Ibáñez María Dolores , Blázquez María Amparo
Published: March 2019

Ginger and turmeric are two food ingredients that are in high demand due to their flavor and positive effects on health. The biological properties of these spices are closely related to the aromatic compounds they contain. The chemical compositions of their essential oils and their in vitro phytotoxic activity against weeds (Portulaca oleracea, Lolium multiflorum, Echinochloa crus-galli, Cortaderia selloana, and Nicotiana glauca) and food crops (tomato, cucumber, and rice) were studied. Forty-one compounds, accounting for a relative peak area of 87.7% and 94.6% of turmeric and ginger essential oils, respectively, were identified by Gas Chromatography–Mass Spectrometry analysis. Ginger essential oil with α-zingiberene (24.9 ± 0.8%), β-sesquiphelladrene (11.7 ± 0.3%), ar-curcumene (10.7 ± 0.2%), and β-bisabolene (10.5 ± 0.3%) as the main compounds significantly inhibited the seed germination of P. oleracea, L. multiflorum, and C. selloana at the highest dose (1 µL/mL) assayed, as well as the hypocotyl and radicle growth of the weeds. Turmeric essential oil with ar-turmerone (38.7 ± 0.8%), β-turmerone (18.6 ± 0.6%), and α-turmerone (14.2 ± 0.9%) as principal components significantly inhibited the seed germination of C. selloana and hypocotyl and radicle growth of weeds (the latter in particular) at the highest dose, whereas it did not affect either the seed germination or seedling growth of the food crops. Turmeric essential oil can be an effective post-emergent bioherbicide against the tested weeds without phytotoxicity to crops.
Effect of Chemical Structure and Salt Concentration on the Crystallization and Ionic Conductivity of Aliphatic Polyethers
Authors: Olmedo-Martínez Jorge L. , Meabe Leire , Basterretxea Andere , Mecerreyes David , Müller Alejandro J.
Published: March 2019

Poly(ethylene oxide) (PEO) is the most widely used polymer in the field of solid polymer electrolytes for batteries. It is well known that the crystallinity of polymer electrolytes strongly affects the ionic conductivity and its electrochemical performance. Nowadays, alternatives to PEO are actively researched in the battery community, showing higher ionic conductivity, electrochemical window, or working temperature range. In this work, we investigated polymer electrolytes based on aliphatic polyethers with a number of methylene units ranging from 2 to 12. Thus, the effect of the lithium bis(trifluoromethanesulfone) imide (LiTFSI) concentration on the crystallization behavior of the new aliphatic polyethers and their ionic conductivity was investigated. In all the cases, the degree of crystallinity and the overall crystallization rate of the polymers decreased drastically with 30 wt % LiTFSI addition. The salt acted as a low molecular diluent to the polyethers according to the expectation of the Flory–Huggins theory for polymer–diluent mixtures. By fitting our results to this theory, the value of the interaction energy density (B) between the polyether and the LiTFSI was calculated, and we show that the value of B must be small to obtain high ionic conductivity electrolytes.
Slip-Spring and Kink Dynamics Models for Fast Extensional Flow of Entangled Polymeric Fluids
Authors: Moghadam Soroush , Saha Dalal Indranil , Larson Ronald G.
Published: March 2019

We combine a slip-spring model with an ‘entangled kink dynamics’ (EKD) model for strong uniaxial extensional flows (with Rouse Weissenberg number W i R ≫ 1 ) of long ( M w > 1   Mkg / mol for polystyrene) entangled polymers in solutions and melts. The slip-spring model captures the dynamics up to the formation of a ‘kinked’ or folded state, while the kink dynamics simulation tracks the dynamics from that point forward to complete extension. We show that a single-chain slip-spring model using affine motion of the slip-spring anchor points produces unrealistically high tension near the center of the chain once the Hencky strain exceeds around unity or so, exceeding the maximum tension that a chain entangled with a second chain is able to support. This unrealistic tension is alleviated by pairing the slip links on one chain with those on a second chain, and allowing some of the large tension on one of the two to be transferred to the second chain, producing non-affine motion of each. This explicit pairing of entanglements mimics the entanglement pairing also used in the EKD model, and allows the slip spring simulations to be carried out to strains high enough for the EKD model to become valid. We show that results nearly equivalent to those from paired chains are obtained in a single-chain slip-spring simulation by simply specifying that the tension in a slip spring cannot exceed the theoretical maximum value of ζ ′ ϵ ˙ L 2 / 8 where ζ ′ , ϵ ˙ and L are the friction per unit length, strain rate and contour length of the chain, respectively. The effects of constraint release (CR) and regeneration of entanglements is also studied and found to have little effect on the chain statistics up to the formation of the kinked state. The resulting hybrid model provides a fast, simple, simulation method to study the response of high molecular weight ( M w > 1   Mkg / mol ) polymers in fast flows ( W i R ≫ 1 ), where conventional simulation techniques are less applicable due to computational cost.
Automatic Estimation of Urban Waterlogging Depths from Video Images Based on Ubiquitous Reference Objects
Authors: Jiang Jingchao , Liu Junzhi , Cheng Changxiu , Huang Jingzhou , Xue Anke
Published: March 2019

Video supervision equipment, which is readily available in most cities, can record the processes of urban floods in video form. Ubiquitous reference objects, which often appear in videos, can be used to indicate urban waterlogging depths. This makes video images a valuable data source for obtaining waterlogging depths. However, the urban waterlogging information contained in video images has not been effectively mined and utilized. In this paper, we present a method to automatically estimate urban waterlogging depths from video images based on ubiquitous reference objects. First, reference objects from video images are detected during the flooding and non-flooding periods using an object detection model with a convolutional neural network (CNN). Then, waterlogging depths are estimated using the height differences between the detected reference objects in these two periods. A case study is used to evaluate the proposed method. The results show that our proposed method could effectively mine and utilize urban waterlogging depth information from video images. This method has the advantages of low economic cost, acceptable accuracy, high spatiotemporal resolution, and wide coverage. It is feasible to promote this proposed method within cities to monitor urban floods.
Identification of the Best Hyperspectral Indices in Estimating Plant Species Richness in Sandy Grasslands
Authors: Peng Yu , Fan Min , Bai Lan , Sang Weiguo , Feng Jinchao , Zhao Zhixin , Tao Ziye
Published: March 2019

Numerous spectral indices have been developed to assess plant diversity. However, since they are developed in different areas and vegetation type, it is difficult to make a comprehensive comparison among these indices. The primary objective of this study was to explore the optimum spectral indices that can predict plant species richness across different communities in sandy grassland. We use 7339 spectral indices (7217 we developed and 122 that were extracted from literature) to predict plant richness using a two-year dataset of plant species and spectra information at 270 plots. For this analysis, we employed cluster analysis, correlation analysis, and stepwise linear regression. The spectral variability within the 420–480 nm and 760–900 nm ranges, the first derivative value at the sensitive bands, and the normalized difference at narrow spectral ranges correlated well with plant species richness. Within the 7339 indices that were investigated, the first-order derivative values at 606 and 583 nm, the reflectance combinations on red bands: (R802 − R465)/(R802 + R681) and (R750 − R550)/(R750 + R550) showed a stable performance in both the independent calibration and validation datasets (R2 > 0.27, p < 0.001, RMSE < 1.7). They can be regarded as the best spectral indices to estimate plant species richness in sandy grasslands. In addition to these spectral variation indices, the first derivative values or the normalized difference of the sensitive bands also reflect plant diversity. These results can help to improve the estimation of plant diversity using satellite-based airborne and hand-held hyperspectral sensors.
Use of Multi-Agent Theory to Resolve Complex Indoor Air Quality Control Problems
Authors: Chen Shang-Yuan , Chen Cheng-Yen
Published: March 2019

Taiwan has suffered from widespread haze and poor air quality during recent years, and the control of indoor air quality has become an important topic. This study relies on Multi-Agent theory in which collected air quality was used in calculations and after agents make decisions in accordance with pre-written rules to construct and indoor air quality control system and conflict resolution mechanism, which will serve to maintain a healthy and comfortable indoor environment. As for implementation, the simulated system used the Arduino open source microcontroller system to collect air quality data and turn on building equipment in order to improve indoor air quality. This study also used the graphic control program LabVIEW to write a control program and user interface. The implementation verifies the feasibility of applying multi-agent theory to air quality control systems, and an Individual intelligent agent has the basic ability to resolve their own conflicts autonomously. However, when there are multiple factors and user status are simultaneously involved in the decision-making, it is difficult for the system to exhaust all conflict conditions, and when context control surpassing the restrictions of binary logic rule-based reasoning, it is necessary to change the algorithm and redesign the system.
Real-Time Healthcare Data Transmission for Remote Patient Monitoring in Patch-Based Hybrid OCC/BLE Networks
Authors: Hasan Moh. Khalid , Shahjalal Md. , Chowdhury Mostafa Zaman , Jang Yeong Min
Published: March 2019

Research on electronic healthcare (eHealth) systems has increased dramatically in recent years. eHealth represents a significant example of the application of the Internet of Things (IoT), characterized by its cost effectiveness, increased reliability, and minimal human effort in nursing assistance. The remote monitoring of patients through a wearable sensing network has outstanding potential in current healthcare systems. Such a network can continuously monitor the vital health conditions (such as heart rate variability, blood pressure, glucose level, and oxygen saturation) of patients with chronic diseases. Low-power radio-frequency (RF) technologies, especially Bluetooth low energy (BLE), play significant roles in modern healthcare. However, most of the RF spectrum is licensed and regulated, and the effect of RF on human health is of major concern. Moreover, the signal-to-noise-plus-interference ratio in high distance can be decreased to a considerable extent, possibly leading to the increase in bit-error rate. Optical camera communication (OCC), which uses a camera to receive data from a light-emitting diode (LED), can be utilized in eHealth to mitigate the limitations of RF. However, OCC also has several limitations, such as high signal-blockage probability. Therefore, in this study, a hybrid OCC/BLE system is proposed to ensure efficient, remote, and real-time transmission of a patient’s electrocardiogram (ECG) signal to a monitor. First, a patch circuit integrating an LED array and BLE transmitter chip is proposed. The patch collects the ECG data according to the health condition of the patient to minimize power consumption. Second, a network selection algorithm is developed for a new network access request generated in the patch circuit. Third, fuzzy logic is employed to select an appropriate camera for data reception. Fourth, a handover mechanism is suggested to ensure efficient network allocation considering the patient’s mobility. Finally, simulations are conducted to demonstrate the performance and reliability of the proposed system.
Reduction of Artefacts in JPEG-XR Compressed Images
Authors: Hua Kai-Lung , Trang Ho Thi , Srinivasan Kathiravan , Chen Yung-Yao , Chen Chun-Hao , Sharma Vishal , Zomaya Albert Y.
Published: March 2019

The JPEG-XR encoding process utilizes two types of transform operations: Photo Overlap Transform (POT) and Photo Core Transform (PCT). Using the Device Porting Kit (DPK) provided by Microsoft, we performed encoding and decoding processes on JPEG XR images. It was discovered that when the quantization parameter is >1-lossy compression conditions, the resulting image displays chequerboard block artefacts, border artefacts and corner artefacts. These artefacts are due to the nonlinearity of transforms used by JPEG-XR. Typically, it is not so visible; however, it can cause problems while copying and scanning applications, as it shows nonlinear transforms when the source and the target of the image have different configurations. Hence, it is important for document image processing pipelines to take such artefacts into account. Additionally, these artefacts are most problematic for high-quality settings and appear more visible at high compression ratios. In this paper, we analyse the cause of the above artefacts. It was found that the main problem lies in the step of POT and quantization. To solve this problem, the use of a “uniform matrix” is proposed. After POT (encoding) and before inverse POT (decoding), an extra step is added to multiply this uniform matrix. Results suggest that it is an easy and effective way to decrease chequerboard, border and corner artefacts, thereby improving the image quality of lossy encoding JPEG XR than the original DPK program with no increased calculation complexity or file size.
Low-Cost Tracking Systems Allow Fine Biomechanical Evaluation of Upper-Limb Daily-Life Gestures in Healthy People and Post-Stroke Patients
Authors: Scano Alessandro , Molteni Franco , Molinari Tosatti Lorenzo
Published: March 2019

Since the release of the first Kinect in 2011, low-cost technologies for upper-limb evaluation has been employed frequently for rehabilitation purposes. However, a limited number of studies have assessed the potential of the Kinect V2 for motor evaluations. In this paper, a simple biomechanical protocol has been developed, in order to assess the performances of healthy people and patients, during daily-life reaching movements, with focus on some of the patients’ common compensatory strategies. The assessment considers shoulder range of motion, elbow range of motion, trunk compensatory strategies, and movement smoothness. Seventy-seven healthy people and twenty post-stroke patients participated to test the biomechanical assessment. The testing protocol included four different experimental conditions: (1) dominant limb and (2) non-dominant limb of 77 healthy people, and (3) the more impaired limb of 20 post-stroke hemiparetic patients, and (4) the less-impaired limb of 11 patients (subgroup of the original 20). Biomechanical performances of the four groups were compared. Results showed that the dominant and non-dominant limbs of healthy people had comparable performances (p > 0.05). On the contrary, condition (3) showed statistically significant differences between the healthy dominant/non-dominant limb and the less-affected limb in hemiparetic patients, for all parameters of assessment (p < 0.001). In some cases, the less-affected limb of the patients also showed statistical differences (p < 0.05), with respect to the healthy people. Such results suggest that Kinect V2 has the potential for being employed at home, laboratory or clinical environment, for the evaluation of patients’ motor performances.
Image-Based Learning to Measure the Space Mean Speed on a Stretch of Road without the Need to Tag Images with Labels
Authors: Lee Jincheol , Roh Seungbin , Shin Johyun , Sohn Keemin
Published: March 2019

Space mean speed cannot be directly measured in the field, although it is a basic parameter that is used to evaluate traffic conditions. An end-to-end convolutional neural network (CNN) was adopted to measure the space mean speed based solely on two consecutive road images. However, tagging images with labels (=true space mean speeds) by manually positioning and tracking every vehicle on road images is a formidable task. The present study was focused on naïve animation images provided by a traffic simulator, because these contain perfect information concerning vehicle movement to attain labels. The animation images, however, seem far-removed from actual photos taken in the field. A cycle-consistent adversarial network (CycleGAN) bridged the reality gap by mapping the animation images into seemingly realistic images that could not be distinguished from real photos. A CNN model trained on the synthesized images was tested on real photos that had been manually labeled. The test performance was comparable to those of state-of-the-art motion-capture technologies. The proposed method showed that deep-learning models to measure the space mean speed could be trained without the need for time-consuming manual annotation.