bluuebunny/crossref_metadata_2025 huggingface dataset:
Corrosion Resistance of Boronized, Aluminized, and Chromized Thermal Diffusion-Coated Steels in Simulated High-Temperature Recovery Boiler Conditions
Authors: Mahdavi Amirhossein , Medvedovski Eugene , Mendoza Gerardo Leal , McDonald André
Published: July 2018

In this study, the high-temperature molten salt corrosion resistance of bare steels and steels with protective coatings, fabricated by thermal diffusion processes (boronizing, aluminizing and chromizing), were investigated and compared. Surface engineering through thermal diffusion can be used to fabricate protective coatings against corrosion, while alleviating issues around possible cracking and spallation that is typical for conventional thermal-sprayed coatings. In this regard, samples of low carbon steel and 316 stainless steel substrates were boronized, chromized, and aluminized through a proprietary thermal diffusion process, while some of the samples were further coated with additional thin oxide and non-oxide layers to create new surface architectures. In order to simulate the actual corrosion conditions in recovery boilers (e.g., from black liquor combustion), the surfaces of the samples sprayed with a modeling salt solution, were exposed to low-temperature (220 ∘C) and high-temperature (600 ∘C) environments. According to microstructural and X-ray diffraction (XRD) studies and results of hardness determination, the coatings with multilayered architectures, with and without additional oxide layers, showed successful resistance to corrosive attack over bare steels. In particular, the samples with boronized and chromized coatings successfully withstood low-temperature corrosive attack, and the samples with aluminized coatings successfully resisted both low- and high-temperature molten salt corrosive attacks. The results of this study conducted for the first time for the thermal diffusion coatings suggest that these coatings with the obtained architectures may be suitable for surface engineering of large-sized steel components and tubing required for recovery boilers and other production units for pulp and paper processing and power generation.
A Low-Cost Temperature-Controlled Chamber Fabricated for Materials Testing
Authors: Ezike Sabastine Chinedu , Alabi Aderemi Babatunde , Ossai Amarachukwu Nneka , Aina Adebayo Olaniyi
Published: July 2018

This paper presents a low-cost temperature-controlled chamber based on the natural radiation principle. The temperature-controlled chamber assembled using a 1.0 mm thick aluminum sheet equipped with expanded polystyrene lagging material, temperature controller, K-type thermocouple and solid-state relay. A high precision temperature sensor (K-type thermocouple) attached to the sample under test (SUT) near the instrument’s measuring point gives a feedback signal to the temperature integrated derivative (TID) controller. The accuracy of temperature readings from the chamber investigated and the chamber itself, calibrated with temperature sensor by Fluke, show temperature readings that correspond to the set temperature values. In addition, perovskite thin film deposited on a glass substrate of 75 × 25 mm was tested and the temperature readings equally correspond to the temperature set values. This low-cost and low-energy-consumption chamber could use in laboratories in the developing world where there is scarce power supply.
Furcation Involvement Classification: A Comprehensive Review and a New System Proposal
Authors: Pilloni Andrea , Rojas Mariana A.
Published: July 2018

Various classification systems have been proposed to describe furcation lesions and Glickman’s classification for many years seems to have been the most widely utilized in the sole clinical diagnosis with no reference to the prognostic value of the lesion itself. This article reviews the previous classification systems and proposes a new method to classify furcation lesions based on the position of the gingival margin and its relationship with the furcation area (clinically exposed/non-exposed furcation area) providing significant aid for a better understanding of furcation involvements and increases the prognostic value of treatments in the long term.
Numerical Study of a Direct Injection Internal Combustion Engine Burning a Blend of Hydrogen and Dimethyl Ether
Authors: Faingold Galia , Tartakovsky Leonid , Frankel Steven H.
Published: July 2018

In the reported study, various aspects of dimethyl ether/hydrogen combustion in a Reactivity Controlled Compression Ignition (RCCI) engine are numerically evaluated using Reynolds Averaged Navier-Stokes (RANS) and Large Eddy Simulation (LES). Early direct injection and mixture propagation were also explored, along with peculiaritis of dimethyl ether combustion modeling. The numerical models are validated using available experimental results of a partially premixed dimethyl ether jet flames and an optically accessible internal combustion engine with direct hydrogen injection. LES showed more predictive results in modeling both combustion and mixture propagation. The same models were applied to a full engine cycle of an RCCI engine with stratified reactivity, to gain phenomenological insight into the physical processes involved in stratified reactivity combustion. We showed that 3D and turbulence considerations had a great impact on simulation results, and the LES was able to capture the pressure oscillations typical for this type of combustion.
Multi-Load Mode Analysis for Electric Vehicle Wireless Supply System
Authors: Jiang Cheng , Sun Yue , Wang Zhihui , Tang Chunsen
Published: July 2018

When electric vehicles (EVs) run on the wireless power supply coils, the multi-load working mode will appear, showing that that more than one EV is collecting energy from one coil. Aiming at the stability problem of multi-load mode, this paper mainly analyzes how the number of loads influences the system stability and defines the boundary condition of the load quantity. Meanwhile, an L-shaped coil structure and the T-shaped magnetic core structure are proposed to solve the problem of coil breakdown for high-power supply situations. The proposed structures effectively reduce the supply coils’ self-inductance on the premise of guaranteeing the power transfer, and ensure the security of the multi-load system. At last, the validity of theoretical analysis is verified by simulations and experiments.
An Equivalent Circuit for the Evaluation of Cross-Country Fault Currents in Medium Voltage (MV) Distribution Networks
Authors: Gatta Fabio Massimo , Geri Alberto , Lauria Stefano , Maccioni Marco
Published: July 2018

A Cross-Country Fault (CCF) is the simultaneous occurrence of a couple of Line-to-Ground Faults (LGFs), affecting different phases of same feeder or of two distinct ones, at different fault locations. CCFs are not uncommon in medium voltage (MV) public distribution networks operated with ungrounded or high-impedance neutral: despite the relatively small value of LGF current that is typical of such networks, CCF currents can be comparable to those that are found in Phase-To-Phase Faults, if the affected feeder(s) consists of cables. This occurs because the faulted cables’ sheaths/screens provide a continuous, relatively low-impedance metallic return path to the fault currents. An accurate evaluation is in order, since the resulting current magnitudes can overheat sheaths/screens, endangering cable joints and other plastic sheaths. Such evaluation, however, requires the modeling of the whole MV network in the phase domain, simulating cable screens and their connections to the primary and secondary substation earth electrodes by suitable computer programs, such as ATP (which is the acronym for alternative transient program) or EMTP (the acronym for electromagnetic transient program), with substantial input data being involved. This paper presents a simplified yet accurate circuit model of the faulted MV network, taking into account the CCF currents’ return path (cable sheaths/screens, ground conductors, and earthing resistances of secondary substations). The proposed CCF model can be implemented in a general-purpose simulation program, and it yields accurate fault currents estimates: for a 20 kV network case study, the comparison with accurate ATP simulations evidences mismatches mostly smaller than 2%, and never exceeding 5%.
Species Identification of Pinus Pollen Found in Belukha Glacier, Russian Altai Mountains, Using a Whole-Genome Amplification Method
Authors: Nakazawa Fumio , Suyama Yoshihisa , Imura Satoshi , Motoyama Hideaki
Published: July 2018

Pollen taxa in sediment samples can be identified based on morphology. However, closely related species do not differ substantially in pollen morphology, and accurate identification is generally limited to genera or families. Because many pollen grains in glaciers contain protoplasm, genetic information obtained from pollen grains should enable the identification of plant taxa at the species level. In the present study, species identification of Pinus pollen grains was attempted using whole-genome amplification (WGA). We used pollen grains extracted from surface snow (depth, 1.8–1.9 m) from the Belukha glacier in the summer of 2003. WGA was performed using a single pollen grain. Some regions of the chloroplast genome were amplified by PCR, and the DNA products were sequenced to identify the pollen grain. Pinus includes approximately 111 recognized species in two subgenera, four sections, and 11 subsections. The tree species Pinus sibirica and P. sylvestris are currently found at the periphery of the glacier. We identified the pollen grains from the Belukha glacier to the level of section or subsection to which P. sibirica and P. sylvestris belong. Moreover, we specifically identified two pollen grains as P. sibirica or P. cembra. Fifteen species, including P. sibirica, were candidates for the remaining pollen grain.
Did Fine Particulate Matter from the Summer 2016 Landscape Fires in Tasmania Increase Emergency Ambulance Dispatches? A Case Crossover Analysis
Authors: Edwards Laura , Williamson Grant , Williams Stephanie , Veitch Mark , Salimi Farhad , Johnston Fay
Published: July 2018

During summer in early 2016, over 70 landscape fires in Tasmania (Australia) caused several severe episodes of fire smoke across the island state. To assess the health impact of the fire smoke, a case crossover analysis was performed, which measured the association between increased concentrations of PM2.5 and emergency ambulance dispatches (EAD) from 1 January to 31 March 2016. Control days were matched by latitude and longitude, day of the week and calendar month. Exposure data were obtained from air quality monitoring stations at lag times of 1–48 h and for the 24-h mean on the same day and 1-day lag. Positive associations were observed between an increase of 10 µg/m3 in PM2.5 and EAD for stroke on the same day (OR 1.10, 95% CI 1.02–1.19) and at 1-day lag (OR 1.10, 95% CI 1.02–1.18). Furthermore, there were non-significant increases in breathing problems (OR 1.04, 95% CI 1.00–1.08) and diabetic problems (OR 1.11, 95% CI 0.99–1.22) at 1-day lag. The EAD for all causes were not increased. These findings will be used for ambulance service planning and public health risk communication in future landscape fire events.
Venomics: A Mini-Review
Authors: Wilson David , Daly Norelle L.
Published: July 2018

Venomics is the integration of proteomic, genomic and transcriptomic approaches to study venoms. Advances in these approaches have enabled increasingly more comprehensive analyses of venoms to be carried out, overcoming to some extent the limitations imposed by the complexity of the venoms and the small quantities that are often available. Advances in bioinformatics and high-throughput functional assay screening approaches have also had a significant impact on venomics. A combination of all these techniques is critical for enhancing our knowledge on the complexity of venoms and their potential therapeutic and agricultural applications. Here we highlight recent advances in these fields and their impact on venom analyses.
Cannibalism as a Possible Entry Route for Opportunistic Pathogenic Bacteria to Insect Hosts, Exemplified by Pseudomonas aeruginosa, a Pathogen of the Giant Mealworm Zophobas morio
Authors: Maciel-Vergara Gabriela , Jensen Annette Bruun , Eilenberg Jørgen
Published: July 2018

Opportunistic bacteria are often ubiquitous and do not trigger disease in insects unless the conditions are specifically favorable for bacterial development in a suitable host. In this paper, we isolated and identified a bacterium, Pseudomonas aeruginosa, from the larvae of the giant mealworm Zophobas morio and we studied the possible entry routes by challenging larvae with per os injection and subdermal injection. We also evaluated the effect of exposing groups of larvae to P. aeruginosa inoculated in their feed and the effect of exposing wounded larvae to P. aeruginosa. We concluded that the mortality rate of Z. morio larvae is higher when P. aeruginosa gets in direct contact with the hemolymph via intracoelomic injection compared to a situation where the bacterium is force-fed. Larvae with an open wound exposed to P. aeruginosa presented higher mortality rate compared to larvae with a wound that was not exposed to the bacterium. We documented too, that cannibalism and scavenging were more prevalent among larvae in a group, when P. aeruginosa is present compared to when it is absent. We discuss hereby different aspects related with the pathogen’s entry routes to insects the complexity of pathogen´s transmission in high population densities and different ways to prevent and/or control P. aeruginosa in mass rearing systems.
Alterations and Interchange of Morphometric Characters in Different Life Cycle Stages with Reference to Genomic Variations of Anopheles subpictus (Diptera; Culicidae) Sibling Species Complex in Sri Lanka
Authors: Jayatunga Dona P. W. , Harischandra Iresha N. , Chandrasekharan Naduviladath V. , De Silva Nissanka K.
Published: July 2018

The species complex of the mosquito Anopheles subpictus is designated by the sibling species A–D, depending on morphological characters of life cycle stages and variations in polytene chromosomes. However, morphological aberrations in the life cycle stages make the identification of sibling species uncertain and imprecise. The objective of the present study is to determine the suitability of morphological variations of sibling species and their genomic variations to identify the sibling species status of an An. subpictus population in Sri Lanka. Life cycle stages of larvae, pupal exuviae, and adults were examined for previously reported distinctive morphological features. Five nuclear and mitochondrial genome regions, including the Internal transcribed spacer 2 (ITS2) region, D3 region, white gene, cytochrome c oxidase I (COI), and Cytochrome b (Cyt-b), were sequenced and analyzed for variations. The eggs changed their distinct sibling morphological characters during metamorphosis (89.33%). The larvae, pupal exuviae, and adult stages showed deviation from their sibling characters by 26.10%, 19.71%, and 15.87%, respectively. However, all the species from the analysis shared two distinct sequence types for all regions, regardless of the morphological variations. In conclusion, the An. subpictus sibling species complex in Sri Lanka is not identifiable using morphological characters due to variations, and the genomic variations are independent from the morphological variations.
Percutaneous Left Main Coronary Intervention: A Review of Plaque Modification in Left Main Percutaneous Coronary Intervention
Authors: Shah Chirag A. , Pfau Steven E.
Published: July 2018

Left main coronary artery (LMCA) stenosis has long been recognized as a marker of increased morbidity and mortality. Current treatment algorithms for LMCA stenosis consider both percutaneous coronary intervention (PCI) with drug eluting stents (DES) and coronary bypass surgery, each with advantages based on individual patient characteristics. Since the LMCA is the largest artery in the coronary tree, plaque volume and calcification is greater than other coronary segments and often extends to the distal bifurcation segment. In LMCA bifurcation lesions, larger minimal stent area is strongly associated with better outcome in the DES era. Plaque modification strategies such as rotational, orbital, or laser atherectomy are effective mechanisms to reduce plaque volume and alter compliance, facilitating stent delivery and stent expansion. We present a case of a calcified, medina class 1,1,1 LMCA lesion where intravascular ultrasound (IVUS) and orbital atherectomy were employed for optimal results. In this context, we review the evidence of plaque modification devices and the rationale for their use in unprotected left main PCI.
Tissue Engineering Scaffolds Fabricated in Dissolvable 3D-Printed Molds for Patient-Specific Craniofacial Bone Regeneration
Authors: De la Lastra Angela Alarcon , Hixon Katherine R. , Aryan Lavanya , Banks Amanda N. , Lin Alexander Y. , Hall Andrew F. , Sell Scott A.
Published: July 2018

The current gold standard treatment for oral clefts is autologous bone grafting. This treatment, however, presents another wound site for the patient, greater discomfort, and pediatric patients have less bone mass for bone grafting. A potential alternative treatment is the use of tissue engineered scaffolds. Hydrogels are well characterized nanoporous scaffolds and cryogels are mechanically durable, macroporous, sponge-like scaffolds. However, there has been limited research on these scaffolds for cleft craniofacial defects. 3D-printed molds can be combined with cryogel/hydrogel fabrication to create patient-specific tissue engineered scaffolds. By combining 3D-printing technology and scaffold fabrication, we were able to create scaffolds with the geometry of three cleft craniofacial defects. The scaffolds were then characterized to assess the effect of the mold on their physical properties. While the scaffolds were able to completely fill the mold, creating the desired geometry, the overall volumes were smaller than expected. The cryogels possessed porosities ranging from 79.7% to 87.2% and high interconnectivity. Additionally, the cryogels swelled from 400% to almost 1500% of their original dry weight while the hydrogel swelling did not reach 500%, demonstrating the ability to fill a defect site. Overall, despite the complex geometry, the cryogel scaffolds displayed ideal properties for bone reconstruction.
Panel Method for Ducted Propellers with Sharp Trailing Edge Duct with Fully Aligned Wake on Blade and Duct
Authors: Kim Seungnam , Kinnas Spyros A. , Du Weikang
Published: July 2018

A low-order panel method is used to predict the performance of ducted propellers. A full wake alignment (FWA) scheme, originally developed to determine the location of the force-free trailing wake of open propellers, is improved and extended to determine the location of the force-free trailing wakes of both the propeller blades and the duct, including the interaction with each other. The present method is applied on a ducted propeller with sharp trailing edge duct, and the predicted results over a wide range of advance ratios, with or without full alignment of the duct wake, are compared with each other, as well as with results from RANS simulations and with measurements from an experiment.
Structure Confirmation and Evaluation of a Nonsteroidal Inhibitor of 17β-Hydroxysteroid Dehydrogenase Type 10
Authors: Boutin Sophie , Poirier Donald
Published: July 2018

17β-Hydroxysteroid dehydrogenase type 10 (17β-HSD10) is a steroidogenesis enzyme known for its potential role in Alzheimer’s disease. For comparison purposes between steroidal and nonsteroidal 17β-HSD10 inhibitors 1 and 2, respectively, we attempted the chemical synthesis of benzothiazole phosphonate derivative 2. Instead of a one-pot synthesis, we report a two-step synthesis with characterization of both imine intermediate 5 and final compound 2. Furthermore, complete assignation of 1H and 13C nuclear magnetic resonance (NMR) signals of 2 is provided, as we observed a divergence of NMR data with those published previously. Finally, biological assays showed that 1 and 2 inhibited the oxidation of estradiol (E2) into estrone (E1) by the 17β-HSD10 recombinant protein. However, in human embryonic kidney (HEK)-293 intact cells transfected with 17β-HSD10, only the steroidal inhibitor 1 induced a dose-dependent inhibition of E2 to E1 transformation.
On the Number of Periodic Inspections During Outbreaks of Discrete-Time Stochastic SIS Epidemic Models
Authors: Gamboa Maria , Lopez-Herrero Maria Jesus
Published: July 2018

This paper deals with an infective process of type SIS, taking place in a closed population of moderate size that is inspected periodically. Our aim is to study the number of inspections that find the epidemic process still in progress. As the underlying mathematical model involves a discrete time Markov chain (DTMC) with a single absorbing state, the number of inspections in an outbreak is a first-passage time into this absorbing state. Cumulative probabilities are numerically determined from a recursive algorithm and expected values came from explicit expressions.
Sorbicillasins A–B and Scirpyrone K from a Deep-Sea-Derived Fungus, Phialocephala sp. FL30r
Authors: Zhang Zhenzhen , He Xueqian , Che Qian , Zhang Guojian , Zhu Tianjiao , Gu Qianqun , Li Dehai
Published: July 2018

Two new nitrogen-containing sorbicillinoids named sorbicillasins A and B (1 and 2) and a new 3,4,6-trisubstituted α-pyrone derivative, scirpyrone K (3), together with two known biosynthetically related polyketides (4–5), were isolated from the deep-sea-derived fungus Phialocephala sp. FL30r by using the OSMAC (one strain-many compounds) method. The structures of 1–3, including absolute configurations, were deduced based on MS, NMR, and time-dependent density functional theory (TD-DFT) calculations of specific ECD (electronic circular dichroism) spectra. Compounds 1 and 2 possessed a novel hexahydropyrimido[2,1-a] isoindole moiety, and compound 3 exhibited weak radical scavenging activity against DPPH (2,2-diphenyl-1-picrylhydrazyl) with an IC50 value of 27.9 μM.
Solid State Hydrogen Storage in Alanates and Alanate-Based Compounds: A Review
Authors: Milanese Chiara , Garroni Sebastiano , Gennari Fabiana , Marini Amedeo , Klassen Thomas , Dornheim Martin , Pistidda Claudio
Published: July 2018

The safest way to store hydrogen is in solid form, physically entrapped in molecular form in highly porous materials, or chemically bound in atomic form in hydrides. Among the different families of these compounds, alkaline and alkaline earth metals alumino-hydrides (alanates) have been regarded as promising storing media and have been extensively studied since 1997, when Bogdanovic and Schwickardi reported that Ti-doped sodium alanate could be reversibly dehydrogenated under moderate conditions. In this review, the preparative methods; the crystal structure; the physico-chemical and hydrogen absorption-desorption properties of the alanates of Li, Na, K, Ca, Mg, Y, Eu, and Sr; and of some of the most interesting multi-cation alanates will be summarized and discussed. The most promising alanate-based reactive hydride composite (RHC) systems developed in the last few years will also be described and commented on concerning their hydrogen absorption and desorption performance.
Another Approach to Characterize Particle Distribution during Surface Composite Fabrication Using Friction Stir Processing
Authors: Gangil Namrata , Maheshwari Sachin , Nasr Emad Abouel , El-Tamimi Abdulaziz M. , El-Meligy Mohammed A. , Siddiquee Arshad Noor
Published: July 2018

Surface composite fabrication through Friction Stir Processing (FSP) is evolving as a useful clean process to enhance surface properties of substrate. Better particle distribution is key to the success of surface composite fabrication which is achieved through multiple passes. Multiple passes significantly increase net energy input and undermine the essence of this clean process. This study proposes a novel approach and indices to relate the particle distribution with the FSP parameters. It also proposes methodology for predicting responses and relate the response with the input parameter. Unit stirring as derived parameter consisting of tool rotation speed in revolutions per minute (rpm), traverse speed and shoulder diameter was proposed. The particle distribution was identified to be achieved in three stages and all three stages bear close relationship with unit stirring. Three discrete stages of particle distribution were identified: degree of spreading, mixing and dispersion. Surface composite on an aerospace grade aluminum alloy AA7050 was fabricated successfully using TiB2 as reinforcement particles. FSP was performed with varied shoulder diameter, rotational speed and traversing speed and constant tool tilt and plunge depth using single pass processing technique to understand the stages of distribution. Significant relationships between processing parameters and stages of particle distribution were identified and discussed.
Linking Temperature, Cation Concentration and Water Activity for the B to Z Conformational Transition in DNA
Authors: Ferreira Jaime M. , Sheardy Richard D.
Published: July 2018

High concentrations of Na+ or [Co(NH3)6]3+ can induce the B to Z conformational transition in alternating (dC-dG) oligo and polynucleotides. The use of short DNA oligomers (dC-dG)4 and (dm5C-dG)4 as models can allow a thermodynamic characterization of the transition. Both form right handed double helical structures (B-DNA) in standard phosphate buffer with 115 mM Na+ at 25 °C. However, at 2.0 M Na+ or 200 μM [Co(NH3)6]3+, (dm5C-dG)4 assumes a left handed double helical structure (Z-DNA) while the unmethylated (dC-dG)4 analogue remains right handed under those conditions. We have previously demonstrated that the enthalpy of the transition at 25 °C for either inducer can be determined using isothermal titration calorimetry (ITC). Here, ITC is used to investigate the linkages between temperature, water activity and DNA conformation. We found that the determined enthalpy for each titration varied linearly with temperature allowing determination of the heat capacity change (ΔCp) between the initial and final states. As expected, the ΔCp values were dependent upon the cation (i.e., Na+ vs. [Co(NH3)6]3+) as well as the sequence of the DNA oligomer (i.e., methylated vs. unmethylated). Osmotic stress experiments were carried out to determine the gain or loss of water by the oligomer induced by the titration. The results are discussed in terms of solvent accessible surface areas, electrostatic interactions and the role of water.
A UPLC-ESI-MS/MS Method for Simultaneous Quantitation of Chlorogenic Acid, Scutellarin, and Scutellarein in Rat Plasma: Application to a Comparative Pharmacokinetic Study in Sham-Operated and MCAO Rats after Oral Administration of Erigeron breviscapus Extract
Authors: Chen Siying , Li Mei , Li Yueting , Hu Hejia , Li Ying , Huang Yong , Zheng Lin , Lu Yuan , Hu Jie , Lan Yanyu , Wang Aimin , Li Yongjun , Gong Zipeng , Wang Yonglin
Published: July 2018

Erigeron breviscapus, a traditional Chinese medicine, is clinically used for the treatment of occlusive cerebral vascular diseases. We developed a sensitive and reliable ultra-performance liquid chromatography-electrospray-tandem mass spectrometry (UPLC-ESI-MS/MS) method for simultaneous quantitation of chlorogenic acid, scutellarin, and scutellarein, the main active constituents in Erigeron breviscapus, and compared the pharmacokinetics of these active ingredients in sham-operated and middle cerebral artery occlusion (MCAO) rats orally administrated with Erigeron breviscapus extract. Plasma samples were collected at 15 time points after oral administration of the Erigeron breviscapus extract. The levels of chlorogenic acid, scutellarin, and scutellarein in rat plasma at various time points were determined by a UPLC-ESI-MS/MS method, and the drug concentration versus time plots were constructed to estimate pharmacokinetic parameters. The concentration of chlorogenic acid in the plasma reached the maximum plasma drug concentration in about 15 min and was below the limit of detection after 4 h. Scutellarin and scutellarein showed the phenomenon of multiple absorption peaks in sham-operated and MCAO rats, respectively. Compared with the sham-operated rats, the terminal elimination half-life of scutellarein in the MCAO rats was prolonged by more than two times and the area under the curve of each component in the MCAO rats was significantly increased. The results showed chlorogenic acid, scutellarin, and scutellarein in MCAO rats had higher drug exposure than that in sham-operated rats, which provided a reference for the development of innovative drugs, optimal dosing regimens, and clinical rational drug use.
Antioxidant, Anti-Inflammatory, and Postulated Cytotoxic Activity of Phenolic and Anthocyanin-Rich Fractions from Polana Raspberry (Rubus idaeus L.) Fruit and Juice—In Vitro Study
Authors: Szymanowska Urszula , Baraniak Barbara , Bogucka-Kocka Anna
Published: July 2018

In this study, the antioxidative and anti-inflammatory potential of crude extracts (CE), anthocyanin-rich fractions (ARF), and phenolic fractions (PF) from raspberry (R) and raspberry juice (J) were evaluated. The antioxidant properties were evaluated with three complementary assays: DPPH radical scavenging activity, chelating Fe(II) power, and ferric reducing power. The highest antioxidant activity was determined for the crude extract from raspberry pulp (RCE) in the case of all methods used. The anti-inflammatory activity was demonstrated by inhibitory effect on lipoxygenase (LOX) and cyclooxygenase-2 (COX-2) activity in vitro. The highest efficiency in inhibiting the activity of both enzymes was exhibited by RCE, 0.79 and 0.59 mg FW/mL, respectively. In turn, JARF had the lowest ability to inhibit LOX (EC50 = 4.5 mg FW/mL) and JPF caused the lowest COX-2 inhibition (1.75 mg FW/mL). Additionally, we have performed a pilot study of in vitro cytotoxic activity using two human leukemia cell lines: J45 and HL60. All examined extracts inhibited the viability of J45 cells more effectively than HL60. The highest cytotoxic effect was observed in the J45.01 cell line after exposure to RCE (EC50 = 0.0375 mg FW/mL).
Correlation Analysis of Phenolic Contents and Antioxidation in Yellow- and Black-Seeded Brassica napus
Authors: Wang Yue , Meng Guisheng , Chen Sailing , Chen Yajie , Jiang Jinjin , Wang You-Ping
Published: July 2018

Brassica napus L. is rich in phenolic components and it has natural antioxidant characteristics which are important to human health. In the present study, the total phenolic and flavonoid contents of developing seeds of yellow- and black-seeded B. napus were compared. Both phenolic and flavonoid contents were significantly higher at 5 weeks after flowering (WAF) in black seeds (6.44 ± 0.97 mg EE/g phenolics and 3.78 ± 0.05 mg EE/g flavonoids) than yellow seeds (2.80 ± 0.13 mg/g phenolics and 0.83 ± 0.01 mg/g flavonoids). HPLC–DAD–ESI/MS analysis revealed different content of 56 phenolic components between yellow and black-seeded B. napus, including kaempferol-3-O-glucoside, isorhamnetin-3-O-glucoside, quercetin-3-O-sophoroside, procyanidin B2 ([DP 2]), which were significantly reduced in yellow seeds compared with black seeds. Applying the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical assay, we found maximum clearance of DPPH and ABTS in the late developmental stages of yellow and black seeds. Additionally, the ferric reducing antioxidant power (FRAP) value maximized at 5 WAF in black seeds (432.52 ± 69.98 μmol Fe (II)/g DW) and 6 WAF in yellow seeds (274.08 ± 2.40 μmol Fe (II)/g DW). Generally, antioxidant ability was significantly reduced in yellow-seeded B. napus compared to black rapeseed, and positive correlations between antioxidation and flavonoid content were found in both yellow- and black-seeded B. napus.
Theoretical Prediction of the Complex P-Glycoprotein Substrate Efflux Based on the Novel Hierarchical Support Vector Regression Scheme
Authors: Chen Chun , Lee Ming-Han , Weng Ching-Feng , Leong Max K.
Published: July 2018

P-glycoprotein (P-gp), a membrane-bound transporter, can eliminate xenobiotics by transporting them out of the cells or blood–brain barrier (BBB) at the expense of ATP hydrolysis. Thus, P-gp mediated efflux plays a pivotal role in altering the absorption and disposition of a wide range of substrates. Nevertheless, the mechanism of P-gp substrate efflux is rather complex since it can take place through active transport and passive permeability in addition to multiple P-gp substrate binding sites. A nonlinear quantitative structure–activity relationship (QSAR) model was developed in this study using the novel machine learning-based hierarchical support vector regression (HSVR) scheme to explore the perplexing relationships between descriptors and efflux ratio. The predictions by HSVR were found to be in good agreement with the observed values for the molecules in the training set (n = 50, r2 = 0.96, qCV2 = 0.94, RMSE = 0.10, s = 0.10) and test set (n = 13, q2 = 0.80–0.87, RMSE = 0.21, s = 0.22). When subjected to a variety of statistical validations, the developed HSVR model consistently met the most stringent criteria. A mock test also asserted the predictivity of HSVR. Consequently, this HSVR model can be adopted to facilitate drug discovery and development.
Quantitative and Chemical Fingerprint Analysis for the Quality Evaluation of Platycodi Radix Collected from Various Regions in China by HPLC Coupled with Chemometrics
Authors: Lu Haiyang , Ju Mengzhen , Chu Shanshan , Xu Tao , Huang Yuzhe , Chan Qingyun , Peng Huasheng , Gui Shuangying
Published: July 2018

Platycodi Radix (PR) is the root of Platycodon grandiflorum (Jacq.) A. DC., which has been used for a long time in China to treat pulmonary diseases. The present study aimed to evaluate the quality of PR samples collected from 23 regions of 11 provinces in China. Eight saponins were quantified using HPLC coupled with evaporative light scattering detection (HPLC-ELSD). The samples with the highest total contents of saponins were from southern China, such as Yunnan, Guangxi, Jiangxi, and Guangzhou. The fingerprint analysis of PR samples was conducted by HPLC-UV method. Nineteen common peaks were selected and the similarity values varied from 0.607 to 0.921. These findings indicated that the saponins contents of PR from different regions varied significantly, with PR samples from southern China having the highest contents of saponins. These comprehensive methods were successful in evaluating the quality of PR samples from northern and southern China, which will serve as a guide for the development of PR as a clinical medication.
Improved Cold Tolerance of Mango Fruit with Enhanced Anthocyanin and Flavonoid Contents
Authors: Sudheeran Pradeep Kumar , Feygenberg Oleg , Maurer Dalia , Alkan Noam
Published: July 2018

Red fruits were suggested to be tolerant to cold. To understand cold-storage tolerance of red mango fruit that were subjected to sunlight at the orchard, mango cv. Shelly from inside (green fruit) or outside (red fruit) the tree canopy was stored for 3 weeks at 5, 8 or 12 °C and examined for flavonoids, antioxidant, volatiles and tolerance to biotic and abiotic stress. Red fruit from the outer canopy showed significant increases in total anthocyanin and flavonoids, and antioxidant activity. Ripening parameters for red and green mango fruit were similar at harvest and during storage. However, red fruit with high anthocyanin and flavonoid contents were more tolerant to biotic and abiotic stresses. After 3 weeks of suboptimal cold storage, green fruit showed significantly more lipid peroxidation and developed significantly more chilling-injury symptoms—black spots and pitting—than red fruit. Volatiles of red and green peels revealed significant modulations in response to cold-storage. Moreover, red fruit were more tolerant to biotic stress and had reduced general decay incidence. However, during long storage at 10 °C for 4, 5 or 6 weeks, red fruit showed a non-significant reduction in decay and chilling injuries. These results suggest new approaches to avoiding chilling injury during cold storage.
Progress in Metabonomics of Type 2 Diabetes Mellitus
Authors: Ma Quantao , Li Yaqi , Wang Min , Tang Ziyan , Wang Ting , Liu Chenyue , Wang Chunguo , Zhao Baosheng
Published: July 2018

With the improvement of living standards and a change in lifestyle, the incidence of type 2 diabetes mellitus (T2DM) is increasing. Its etiology is too complex to be completely understand yet. Metabonomics techniques are used to study the changes of metabolites and metabolic pathways before and after the onset of diabetes and make it more possible to further understand the pathogenesis of T2DM and improve its prediction, early diagnosis, and treatment. In this review, we summarized the metabonomics study of T2DM in recent years and provided a theoretical basis for the study of pathogenesis and the effective prevention and treatment of T2DM.
Evaluation of the Antioxidant and Neuroprotectant Activities of New Asymmetrical 1,3-Diketones
Authors: Nieto Carla I. , Cornago María Pilar , Cabildo María Pilar , Sanz Dionisia , Claramunt Rosa M. , Torralba María Carmen , Torres María Rosario , Martínez Casanova Diana , Sánchez-Alegre Yaiza Rebeca , Escudero Esther , Lavandera José Luis
Published: July 2018

A series of fourteen new asymmetrical 1,3-diketone derivatives have been synthesized and evaluated in the ABTS, FRAP and DPPH assays as a new chemotype with antioxidant and drug-like properties. All the compounds displayed low cytotoxicity in comparison to curcumin against the human neuroblastoma SH-SY5Y cell line. Among them, (3Z,5E)-6-(2,5-difluoro-4-hydroxy-phenyl)-1,1,1-trifluoro-4-hydroxyhexa-3,5-dien-2-one (6b) and (3Z,5E)-6-(2,3-difluoro-4-hydroxy-phenyl)-1,1,1-trifluoro-4-hydroxyhexa-3,5-dien-2-one (7b) with excellent solubility and chemical stability in biorelevant media, have also shown a similar Fe+2 chelation behavior to that of curcumin. Additionally, both derivatives 6b and 7b have afforded good neuroprotection activity against H2O2 induced oxidative stress in the same neuronal cell line, with a significant reduction of intracellular ROS levels, in parallel with a good recovery of the Mitochondrial Membrane Potential (ΔΨm). Compounds 6b and 7b with a promising antioxidant and drug-like profile, with low cytotoxic and good neuroprotectant activity, constitute a new interesting chemical class with high potential as new therapeutic agents against neurodegenerative diseases.
Determination of the Five Main Terpenoids in Different Tissues of Wolfiporia cocos
Authors: Fu Ming , Wang Li , Wang Xianyou , Deng Boxia , Hu Xing , Zou Juan
Published: July 2018

Wolfiporia cocos is a fungus containing triterpenoids and is widely used as an herbal medicine. However, it is unknown whether its main triterpenoid contents differ in different tissues. In this study, we identified dehydrotumulosic acid, polyporenic acid C, pachymic acid, dehydrotrametenolic acid, and dehydroeburicoic acid as the five main triterpenoids in W. cocos. We also systematically profiled the contents and distribution of these main triterpenoids in different tissues of W. cocos. High contents of all five triterpenoids were found in the surface layer of W. cocos. Intriguingly, we noted that the highest contents of the five triterpenoids were found in the surface layer of the sclerotium grown under pollution-controlled cultivation; the second-highest contents were found in the surface layer of the natural sclerotium. These results indicate that environmentally friendly cultivation of the sclerotium of W. cocos is a practical way to increase the productivity of W. cocos. In addition, our findings suggest that the triterpenoids may contribute to the pharmacological activity of W. cocos, and the surface layer of sclerotium in W. cocos might be a promising raw material for applications in health care and the development of functional medical products.
Squalene Cyclases and Cycloartenol Synthases from Polystichum polyblepharum and Six Allied Ferns
Authors: Shinozaki Junichi , Nakene Takahisa , Takano Akihito
Published: July 2018

Ferns are the most primitive of all vascular plants. One of the characteristics distinguishing them from flowering plants is its triterpene metabolism. Most cyclic triterpenes in ferns are hydrocarbons derived from the direct cyclization of squalene by squalene cyclases (SCs). Both ferns and more complex plants share sterols and biosynthetic enzymes, such as cycloartenol synthases (CASs). Polystichum belongs to Dryopteridaceae, and is one of the most species-rich of all fern genera. Several Polystichum ferns in Japan are classified as one of three possible chemotypes, based on their triterpene profiles. In this study, we describe the molecular cloning and functional characterization of cDNAs encoding a SC (PPH) and a CAS (PPX) from the type species Polystichum polyblepharum. Heterologous expression in Pichia pastoris revealed that PPH and PPX are hydroxyhopane synthase and CAS, respectively. By using the PPH and PPX sequences, we successfully isolated SC- and CAS-encoding cDNAs from six Polystichum ferns. Phylogenetic analysis, based on SCs and oxidosqualene cyclase sequences, suggested that the Polystichum subclade in the fern SC and CAS clades reflects the chemotype—but not the molecular phylogeny constructed using plastid molecular markers. These results show a possible relation between triterpenes and their biosynthetic enzymes in Polystichum.
From Plant Compounds to Botanicals and Back: A Current Snapshot
Authors: Durazzo Alessandra , D’Addezio Laura , Camilli Emanuela , Piccinelli Raffaela , Turrini Aida , Marletta Luisa , Marconi Stefania , Lucarini Massimo , Lisciani Silvia , Gabrielli Paolo , Gambelli Loretta , Aguzzi Altero , Sette Stefania
Published: July 2018

This work aims at giving an updated picture of the strict interaction between main plant biologically active compounds and botanicals. The main features of the emerging class of dietary supplements, the botanicals, are highlighted. Focus is also on the definition of actual possibilities of study approach and research strategies. Examples of innovative directions are given: assessment of interaction of bioactive compounds, chemometrics and the new goal of biorefineries. Current models of existing databases, such as plant metabolic pathways, food composition, bioactive compounds, dietary supplements, and dietary markers, are described as usable tools for health research. The need for categorization of botanicals as well as for the implementation of specific and dedicated databases emerged, based on both analytical data and collected data taken from literature throughout a harmonized and standardized approach for the evaluation of an adequate dietary intake.
Neurogenic Differentiation of Human Dental Pulp Stem Cells on Graphene-Polycaprolactone Hybrid Nanofibers
Authors: Seonwoo Hoon , Jang Kyung-Je , Lee Dohyeon , Park Sunho , Lee Myungchul , Park Sangbae , Lim Ki-Taek , Kim Jangho , Chung Jong Hoon
Published: July 2018

Stem cells derived from dental tissues—dental stem cells—are favored due to their easy acquisition. Among them, dental pulp stem cells (DPSCs) extracted from the dental pulp have many advantages, such as high proliferation and a highly purified population. Although their ability for neurogenic differentiation has been highlighted and neurogenic differentiation using electrospun nanofibers (NFs) has been performed, graphene-incorporated NFs have never been applied for DPSC neurogenic differentiation. Here, reduced graphene oxide (RGO)-polycaprolactone (PCL) hybrid electrospun NFs were developed and applied for enhanced neurogenesis of DPSCs. First, RGO-PCL NFs were fabricated by electrospinning with incorporation of RGO and alignments, and their chemical and morphological characteristics were evaluated. Furthermore, in vitro NF properties, such as influence on the cellular alignments and cell viability of DPSCs, were also analyzed. The influences of NFs on DPSCs neurogenesis were also analyzed. The results confirmed that an appropriate concentration of RGO promoted better DPSC neurogenesis. Furthermore, the use of random NFs facilitated contiguous junctions of differentiated cells, whereas the use of aligned NFs facilitated an aligned junction of differentiated cells along the direction of NF alignments. Our findings showed that RGO-PCL NFs can be a useful tool for DPSC neurogenesis, which will help regeneration in neurodegenerative and neurodefective diseases.
Synthesis of Carbon Nanotube Arrays with High Aspect Ratio via Ni-Catalyzed Pyrolysis of Waste Polyethylene
Authors: Zheng Yangfan , Zhang Haijun , Ge Shengtao , Song Jianbo , Wang Junkai , Zhang Shaowei
Published: July 2018

Carbon nanotube (CNT) arrays 30–50 nm in diameter and with a length of several micrometers were prepared by catalytic pyrolysis of waste polyethylene in Ar at 773−1073 K using nickel dichloride as a catalyst precursor. X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectrometry (Raman), a vibrating-sample magnetometer (VSM), and nitrogen adsorption/desorption were used to investigate the effects of the pyrolysis temperature and catalyst contents on the preparation of the aligned CNTs. As results, the as-obtained CNTs had an outer diameter of 30 nm, a wall thickness of 10 nm, and a length of about 50 μm, and their aspect ratio was high up to 1500. The aligned CNTs containing 0.75 wt% Ni prepared at 973 K exhibited good adsorption performance for methylene blue (MB); furthermore, benefiting from the special magnetic properties of residual Ni catalysts, the as-obtained CNTs could be easily magnetically recycled from the treated solution after adsorption.
Kinetically-Controlled Growth of Chestnut-Like Au Nanocrystals with High-Density Tips and Their High SERS Performances on Organochlorine Pesticides
Authors: Zhou Xia , Zhao Qian , Liu Guangqiang , Zhang Hongwen , Li Yue , Cai Weiping
Published: July 2018

A modified seed growth route was developed to fabricate the Au nanocrystals with high-density tips based on kinetically-controlled growth via adjusting the adding rate of Au seeds into growth solution. The obtained Au nanostructures were chestnut-like in morphology and about 100 nm in size. They were built of the radial [111]-oriented nanoneedles and were 30–50 nm in length. There were about 120–150 tips in each nanocrystal. The formation of chestnut-like Au nanocrystals is ascribed to surfactant-induced preferential growth of seeds along direction [111]. Importantly, the chestnut-like Au configuration displayed powerful surface enhanced Raman scattering (SERS) performance (enhance factor > 107), owing to the high density of tips. Further, such film was used as a SERS substrate for the detection of lindane (γ-666) molecules (the typical organochlorine pesticide). The detection limit was about 10 ppb, and the relationship between SERS intensity I and concentration C of 666 accords with the double logarithm linear. This work presents a simple approach to Au nanocrystal with high-density tips, and provides a highly efficacious SERS-substrate for quantitative and trace recognition of toxic chlorinated pesticides.