bluuebunny/crossref_metadata_2025 huggingface dataset:
Preparation of High Loading Pt Nanoparticles on Multiwalled Carbon Nanotubes by Electrodeposition Method Applied for the Anode of Proton Exchange Membrane Fuel Cells
Authors: Hu Sin Yi , Yeh Tsung-Kuang , Wang Mei-Ya
Published: September 2016

Carbon nanotubes (CNTs) by chemical vapor deposition (CVD) were directly grown on carbon paper (CP) to increase the surface area where the catalysts were deposited. After that, platinum (Pt) nanoparticle catalysts were deposited on CNTs by the electrochemical deposition method for proton exchange membrane fuel cell (PEMFC) electrode applications. The physicochemical characterization of Pt/CNTs/CP was observed by scanning electron microscope (SEM), transmission electron microscopy (TEM) and high resolution X-ray photoelectron spectroscopy (HRXPS). The Pt loading was obtained by inductively coupled plasma mass spectrometry (ICP-MS). The electrochemical characterizations were obtained by cyclic voltammetry in argon saturated 0.5M H2SO4, and 0.5M H2SO4 added 1M CH3OH solution, respectively. The results showed that the Pt nanoparticle sizes in the range of 3-5nm were formed on CNTs, and the pulsed electrodeposition provide uniform distribution catalysts. The single cell tests indicated the power density of the homemade MEA could reach up to 927mW/cm2 which is 50% higher than that of the commercial MEA.
Physical Entrainment versus Chemical Binding: Carbon Nanofoam, Metal Nanoparticles, and the Role of Thiophene Linkers
Authors: Parker Joseph F. , Wallace Jean Marie , Brandell Natalie L. , Rolison Debra R.
Published: September 2016

High-surface-area mesoporous carbon nanofoams with pore networks interconnected in 3D are particularly versatile electrodes because the surface of the networked carbon can be modified with energy-storing or catalytic materials. The resulting carbon nanostructured papers are device-ready electrodes decorated with well-dispersed, electron-wired, nanoscale functional materials directly sited in the flow field within the through-connected 3D pore network. We can also pre–modify the carbon paper–supported nanofoams with thiophene-like "hooks" to anchor pre–formed Au nanoparticles adsorbed from colloidal sols. We characterize these native or thiophenylated carbon architectures before and after adsorbing either 5-nm or 15-nm Au colloids by scanning electron microscopy, X-ray photoelectron spectroscopy, and in terms of their electrochemical activity for ethanol oxidation. With these four sets of structurally related electrodes, we can assess whether the metal nanoparticles chemically bind at heterocyclic sulfur in the carbon walls or if they are physically entrained within the nanometric nooks of the ultraporous carbon nanofoam paper.
Molecular Dynamics Analysis of Graphene-Based Nanoelectromechanical Switch
Authors: Lee Eunae , Kang Jeong Won
Published: September 2016

Here we present graphene-based nanoelectromechanical switch with the vertical carbon nanotube electrode via classical molecular dynamics simulations. The carbon nanotube is grown in the center of the square hole and the graphene covers on the hole. The potential difference between the bottom of the hole and the graphene is applied to deflect the graphene. By performing classical molecular dynamic simulations, we investigate the electromechanical properties of graphene-based nanoelectro- mechanical switch with carbon nanotube electrode, which can be switched by the externally applied force. This simulation work explicitly demonstrated that such devices are applicable to nanoscale sensors and quantum computing, as well as ultra-fast-response switching devices.
(Invited) Long Term Stability of Antimony Sulfide-Based Hybrid Solar Cells
Authors: Hayakawa Akinobu , Yukawa Mayumi , Sagawa Takashi
Published: September 2016

Sb2S3-based hybrid solar cells with electron transporting layer of TiO2 or ZnO nanoparticles in addition to poly(3-hexylthiophene)-2,5-diyl / (3, 4-ethylenedioxythiophene) : poly(styrene sulfonate), zinc phthalocyanine (ZnPc), or MoO3 for hole transporting layer were prepared and compared their photovoltaic properties with or without encapsulation by using glass and UV cut-off film. Among these hybrid solar cells, it was found that a combination of glass-ITO/TiO2/Sb2S3/ZnPC/Au encapsulated with glass and UV cut filter has the highest durability with keeping the relative power conversion efficiency of 90% through the stability test under 1 sun at 63 °C at a relative humidity of 50% for 1,500 h.
Environmental-Friendly Fluorine Mixture for CVD Cleaning Processes to Replace C2F6, CF4 and NF3
Authors: Wieland Robert , Pittroff Michael , Boudaden Jamila , Altmannshofer Stephan , Kutter Christoph
Published: September 2016

The target of this work was to find viable alternative CVD-cleaning gas mixtures for the semiconductor industry, which are environmental-friendly and in addition can be used as a “drop in” to avoid high investment costs from equipment modification. Our study has demonstrated that this can be achieved with F2-based gas mixtures, which also provide a more efficient and faster cleaning behavior for most applications. A cleaning efficiency gain of a factor 1.3 up to 17 can be expected, relative to the F2-amount required for cleaning. This gain in efficiency depends on the cleaning gas to be replaced and on the reactor type. A shorter cleaning time can lead into a higher equipment throughput and more cost effective usage of thin film tools. To generate data on particle and tool attrition, a first “mini marathon” test run has been performed. The test reactor, a 200mm wafer size CVD tool, was equipped with a mass spectrometer to monitor the end point of the chamber cleaning and to gain an overview of the waste gases going into the abatement system
SEM Analysis of Electrophoretically-Deposited Cobalt Ferrite Films
Authors: Verma Neil , Talbot J. B.
Published: September 2016

Cobalt ferrite nanoparticles were synthesized and electrophoretically deposited onto aluminum foil, graphite paper, and carbon felt. The resulting cobalt ferrite films were studied to determine their potential for use as an electrocatalyst for the oxidation of ammonium sulfite to ammonium sulfate for a proposed sulfur ammonia thermochemical cycle for hydrogen production. The effects of electrophoretic deposition conditions on deposit morphology and the effects of deposit morphology on electrochemical activity in 2M ammonium sulfite were investigated by SEM analysis.
Deposition of Pt Nanoparticles on Ni Foam Via Galvanic Displacement
Authors: Tamasauskaite-Tamasiunaite Loreta , Zabielaite Ausrine , Balciunaite Aldona , Sebeka Benjaminas , Stalnioniene Irena , Buzas Vytenis , Maciulis Laurynas , Tumonis Liudas , Norkus Eugenijus
Published: September 2016

In the present study the Ni foam was modified with Pt nanoparticles via the galvanic displacement technique. A thin electroless Ni sublayer was deposited on the Ni foam substrate. Then, Pt nanoparticles were deposited on Ni/Nifoam by its immersion into a platinum-containing solution for various time periods. The morphology, structure and composition of the prepared catalysts were examined by means of FESEM, EDAX, and ICP-OES. The catalytic activity of PtNi/Nifoam with different Pt loadings was determined by measuring the amount of H2 generated directly from aqueous alkaline solutions of NaBH4 and compared with that of Ni/Nifoam. It was found that the PtNi/Nifoam catalysts show enhanced catalytic activity towards hydrogen generation as compared to that of Ni/Nifoam.
The Role of Electrolyte Composition on Codeposited Ag and Cu
Authors: Ulu Fulya , Demirci Gökhan , Erdogan Metehan , Karakaya Ishak
Published: September 2016

The eutectic Ag-Cu composition is a common brazing alloy. A complex ion bath containing KAg(CN)2, CuCN, KCN and K4P2O7 was used to codeposit Ag and Cu. The effects of KAg(CN)2, KCN and K4P2O7 concentrations on the composition and morphology of electrodeposited Ag-Cu films was investigated in this study. A constant CuCN concentration of 0.1 M was used. The increase in KCN and KAg(CN)2 concentrations caused major increases in Ag contents, but increase in K4P2O7 concentration caused a minor decrease in Ag content of the film. The deposits were found to be globular clusters when high KAg(CN)2 concentrations were used. Finer microstructures and higher Ag contents were observed in deposits produced in electrolytes containing higher KCN concentrations.
Black Liquor Electrolysis for Hydrogen and Lignin Extraction
Authors: Oliveira Raisa Costa Paes , Mateus Maria , Santos Diogo M.F.
Published: September 2016

Black liquor is a pulp mill effluent from wood cooking with a solid content of 15-18 wt.%, which is mostly lignin. The present study focuses the electrolysis of black liquor for energy recovery. The process has several economic and environmental advantages, as it simultaneously generates a clean fuel (hydrogen) at the cathode and a precipitated material with economic value (lignin) at the anode surface. Platinum, nickel, and AISI 304 stainless steel bulk electrodes are tested for black liquor electrolysis, both as anodes and as cathodes. Voltammetric methods are used to study the lignin oxidation in the black liquor at room temperature, allowing the calculation of kinetic parameters such as the charge transfer coefficient and the number of exchanged electrons. The hydrogen evolution reaction in the black liquor is also evaluated. A small-scale laboratory black liquor electrolyzer using Ni plates is assembled and its operation parameters are evaluated.
(Invited) Understanding and Controlling Chemo-Mechanical Coupling in Perovskite Oxides
Authors: Perry Nicola H. , Marrocchelli Dario , Bishop Sean R. , Tuller Harry L.
Published: September 2016

Mixed ionic and electronic conducting perovskites that can readily exchange oxygen with the atmosphere exhibit a chemo-mechanical coupling between their oxygen content and their lattice dimensions. The lattice dilation accompanying oxygen loss, termed “chemical expansion,” causes large chemical stresses in devices during operation that can lead to mechanical failure. This paper describes our work aimed at understanding, across multiple length scales, which factors impact chemical expansion coefficients in perovskites. Polycrystalline gallate and titanate perovskites containing multivalent Ni, Fe, and Co have been studied using in situ thermogravimetry, dilatometry, and diffraction to probe the chemical expansion process at macroscopic and crystal structure levels. Density functional theory, molecular dynamics, and empirical simulations have provided atomistic insight into changes taking place on the anion and cation sublattices during oxygen loss. Factors impacting the magnitude of the chemo-mechanical coupling, including oxygen vacancy radii, charge localization on cations, temperature, and crystal symmetry have been identified.
Mechano-Chemical Coupling in Double Perovskites as Energy Related Materials
Authors: Tsvetkov Dmitry S. , Ivanov Ivan L. , Malyshkin Dmitry , Sereda Vladimir V. , Zuev Andrey Yu.
Published: September 2016

Double perovskites RBaB2O6-δ and Sr2
BMoO6, where R=rare-earth element and B=3d-transition metal, with A-site and B-site, respectively, cation ordering are very promising materials for a variety of different devices for moderate high temperature applications such as solid oxide fuel cells (SOFCs) and mixed ionic and electronic conducting (MIEC) membranes. The unique feature of the oxides is their ability to undergo both thermal strain and that induced by the defects of oxygen nonstoichiometry in the oxide lattice. The latter is called as chemical or defect-induced strain. This property was shown recently to be anisotropic for tetragonal double perovskites unlike that for perovskites with pseudo-cubic structure. The crystal lattice of a double perovskite expands along a-axis and simultaneously contracts along c
-axis with the decreasing lattice oxygen content. Expansion along a-axis was found to obey the model for pseudo-cubic oxides proposed by us earlier and based on relative change of mean ionic radius. The possible reasons for lattice contraction along c axis are discussed as well.
Characterization and Performance of Proton Conducting Solid Oxide Fuel Cells Manufactured Using Reactive Spray Deposition Technology
Authors: Myles Timothy D. , Ouimet Ryan , Kwak Dongwook , Maric Radenka
Published: September 2016

Proton conducting solid oxide fuel cells (SOFCs) have received attention as a possible alternative to traditional oxygen anion conducting SOFCs. The reason is existing proton conducting perovskites display ionic conductivity similar to yttria-stabilized zirconia at lower temperatures. Lower operating temperatures alleviate durability issues and open the door for the use of low cost stainless steels in cell construction. This study examines the use of reactive spray deposition technology (RSDT) as a means of producing a low cost, metal supported proton conducting SOFC by directly depositing layer after layer onto a metal substrate and with a no need for additional sintering steps. The deposited materials are characterized using SEM, STEM, and XRD techniques.
Electrochemical Studies of L-Cysteine
Authors: Cheek Graham T. , Worosz Matthew A.
Published: September 2016

The electrochemical behavior of L-cysteine has been studied at platinum, gold, and glassy carbon in various media. In 0.10 M KNO3, L-cysteine undergoes a one-electron oxidation at platinum to form cystine. At gold in pH 7.4 phosphate buffer, evidence has been obtained for an abrupt change in surface structure as L-cysteine is added. Addition of L-cysteine to ZnSO4 in 0.10M KNO3 has a dramatic impact on both Zn deposition / stripping and the L-cysteine electrochemistry. The electrochemical behavior of L-cysteine in formamide has been found to be somewhat similar to that in aqueous solutions.
Electrochemical Preparation of Electro-Active Polymers Having Nitrogen Atom: Chiral Polycarbazole Prepared in Chiral Liquid Crystal by Electrochemical Polymerization
Authors: Eguchi Naoto , Goto Hiromasa
Published: September 2016

Polycarbazole was electrochemically synthesized in liquid crystal electrolyte solution on ITO glass. The liquid crystal electrolyte solution contains monomer, supporting salt, and matrix liquid crystal. Polarizing optical microscopy observation revealed that the polymer film thus obtained showed fingerprint optical texture derived from the morphology of the liquid crystal electrolyte solution. This result indicates that molecular transcription occurred from molecular level to macroscopic levels. UV-vis optical absorption measurement confirmed that polycarbazole film was successfully obtained by the electrochemical polymerization. Color of the polymer film can be changed from green (as-prepared) to yellow (reduced state) via reduction. Circular dichroism measurement revealed that this polymer film shows optical activity.
Graphene-Supported Au-Ni Carbon Nitride Electrocatalysts for the ORR in Alkaline Environment
Authors: Negro Enrico , Bach Delpeuch Antoine , Vezzù Keti , Polizzi Stefano , Bertasi Federico , Nawn Graeme , Pagot Gioele , Di Noto Vito
Published: September 2016

This study reports the preparation and characterization of a new family of electrocatalysts (ECs) for the oxygen reduction reaction (ORR) exhibiting a “core-shell” morphology. The “core” consists of graphene sheets, which are covered by a carbon nitride (CN) “shell” embedding Au and Ni active sites. The investigated ECs are labeled AuNi10-CNl 600/Gr and AuNi10-CNl 900/Gr. The chemical composition and thermal stability are studied by inductively-coupled plasma atomic emission spectroscopy (ICP-AES), elemental analysis and by high-resolution thermogravimetric analysis (HR-TGA). The morphology of the ECs is probed by scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM) and powder X-ray diffraction (XRD). The ORR performance of the ECs is studied both in acid (0.1 M HClO4) and in alkaline medium (0.1 M KOH) by Cyclic Voltammetry with the Thin-Film Rotating Ring-Disk Electrode (CV-TF-RRDE) method. Both ECs exhibit a promising performance in the ORR in the alkaline medium.
Synthesis of Reduced Graphene Oxide-Supported PtAu Catalysts and Their Electrocatalytic Activity for Formic Acid Oxidation
Authors: Jeevagan Arockiam John , Gunji Takao , Tanabe Toyokazu , Kaneko Shingo , Matsumoto Futoshi
Published: September 2016

In this paper, we demonstrate a one-pot synthesis of a reduced graphene oxide (RGO)-supported freely assembled binary alloy catalyst (PtAu/RGO) under alkaline conditions. The synthesized PtAu/RGO catalyst was characterized by powder X-ray diffraction (pXRD), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS). It was found that graphene oxide (GO) was successfully reduced to RGO. The PtAu nanoparticles exhibited an alloyed structure with an average diameter of approximately 3.60 ± 0.20 nm and were uniformly distributed across the RGO surface. Furthermore, the electrocatalytic activity of the catalyst for formic acid (FA) oxidation was examined, and it exhibited better catalytic activity for the FA oxidation reaction.
Electrochemical Approaches to Phenylphosphine Oxide Derivatives Synthesis
Authors: Khrizanforova Vera , Khrizanforov Mikhail , Gryaznova Tatyana , Budnikova Yulia
Published: September 2016

Сatalytic direct phosphonation of aromatic C(sp2)-H bonds electrochemically induced were realized for the synthesis of diphenylphosphine oxide derivatives. Electrochemical pathway to CH/PH cross-coupling of phenylacetylene and diphenylphosphine oxide has been performed. The bisphosphine oxide and target diphenyl(phenylethynyl)phosphine oxide were obtained with mild to high yield.
Exploring Extracellular Electron Transfer in Hyperthermophiles for Electrochemical Energy Conversion
Authors: Sekar Narendran , Wu Chang-Hao , Adams Michael W. W. , Ramasamy Ramaraja P.
Published: September 2016

Hyperthermophiles are microorganisms that thrive in extremely hot environment from 80 °C and upwards. They are the most primitive organisms evolved to survive in the early uninhabitable earth. We explored the extracellular electron transfer ability of a hyperthermophilic archaeon called Pyrococccus furiosus (Pf). Pf is an aquatic anaerobe that grows optimally at 100 °C using a wide range of substrates such as carbohydrates and peptides. Their ability to reduce the extracellular oxidants such as insoluble Fe(III) oxide and soluble Fe(III) citrate has been investigated. Pf reduced Fe(III) oxide during its growth at 90 °C and the Pf culture re-suspended in MOPS buffer (pH 7.5) was found to reduce Fe(III) citrate significantly using H2 as an electron donor. Further, Pf grown in two-chamber microbial fuel cell (MFC) at 90 °C was found to show a significant electrochemical response compared to the un-inoculated control MFC. The proof of concept study reported here reveals the potential of Pf to generate electricity in MFCs at high temperature locations such as hydrothermal vents.
DNA Electrochemical Hybridization Detection in Droplets Using Gold Ultramicroelectrodes in a Two-Electrode Configuration
Authors: Horny Marie-Charlotte , Lazerges Mathieu , Siaugue Jean-Michel , Pallandre Antoine , Haghiri-Gosnet Anne-Marie , Gamby Jean
Published: September 2016

A 23-base DNA probe monolayer was self-assembled on a 25-μm gold microelectrode via thiol adsorption. Long-range electron transfer and the use of the redox methylene blue as DNA intercalator were chosen for the monitoring of the hybridization step. The electrochemical properties of the sensor were screened with the [Fe(III)(CN)6]3-/[Fe(II)(CN)6]4- redox couple in cyclic voltammetry in a two-electrode configuration well adapted in the case of microliter biological samples. A study of the stability of the self-assembled monolayer is included in this work. The femtomolar limit of detection for DNA target quantification was deduced from the current density measured and blank measurements depicting the desorption rate of the thiolated DNA probes.
Micro Device for Bio-Particle Positioning in a 3D Space Based on Carbon MEMS and Dielectrophoretic Forces
Authors: Pilloni Oscar , Benítez José Luis , Olguín Luis F. , Palacios-Morales Carlos A. , Oropeza-Ramos Laura
Published: September 2016

The positioning of micron sized bio particles is of great interest to fields like medicine and biology. We introduce a device that would aid in the positioning of bio particles in a tridimensional space, using a combination of individually addressable planar and 3D carbon micro electrodes to exert a dielectrophoretic (DEP) force. Fabrication and test of the device were performed. Working principle of the motion of micron-sized particles using DEP is characterized by particle image velocimetry.
Development and Characterization of Fuel Cell Sensor for Potential Transdermal Ethanol Sensing
Authors: Jalal Ahmed Hasnain , Umasankar Yogeswaran , Bhansali Shekhar
Published: September 2016

Existing fuel cell alcohol sensors suffer from humidity interference and signal instability which renders them useless for transdermal ethanol detection in a non-ideal environment. To address these insufficiencies in fuel cell sensors, various electrode designs, along with the catalysts that would best improve response, were explored in this work. The designs include both two and three electrode setups with Nafion as the proton exchanging membrane. The three-electrode setup provided a more stable signal compared to the two-electrode setup. Considering the development of a potential transdermal ethanol sensor, the ethanol exposed area of the working electrode was optimized to be 1cm2. Catalysts such as Cu, stainless steel, and Ni were studied in these experiments and it was determined that Ni demonstrated the best catalytic activity for ethanol oxidation and oxygen reduction; providing 300 times greater current response than Fe and 3 times greater than Cu. The lower detection limit of the sensor is 1 part per million (ppm) and the sensitivity of the fuel cell sensor using the Ni catalyst was found to be 0.02 nAppm-1 in this study.
Electrochemical Performance and Chemical Stability of Architecturally Designed La2-XPrxNiO4+δ IT-SOFC Cathodes
Authors: Sharma Rakesh Kumar , Celikbilek Ozden , Burriel Mónica , Dessemond Laurent , Bassat Jean-Marc , Djurado Elisabeth
Published: September 2016

In this work, La2-xPrxNiO4+δ (with x=0.0, 0.5, 1 and 2) films have been prepared and studied with the aim of determining the best compromise between stability and electrochemical properties. Indeed La2NiO4+δ is known to exhibit a higher chemical stability while Pr2NiO4+δ presents better electrochemical properties. The properties of mixed phases were found intermediate between those of Pr2NiO4+δ and La2NiO4+δ. The chemical stability decreases by increasing the Pr content. Furthermore, novel double layer La2-xPrxNiO4+δ cathodes were designed by electrostatic spray deposition followed by screen-printing. The polarization resistance (Rpol) of a double layer LaPrNiO4+δ cathode was found equal to 0.11 W cm2 at 600 °C, which is the lowest value available in the literature for this composition.
Agglomeration in Porous Silicon Prepared from Si-Nanowire Structures
Authors: Velez Victor H. , Sundaram Kalpathy B , Sacharia Albin
Published: September 2016

Porous silicon nanowires (SiNWs) have shown excellent properties like low reflection and high luminescence characteristics in the visible region of the optical spectrum. This indicates that porous SiNWs have a great potential applications for optoelectronics and chemical sensors. In this work, silicon nanowires have been prepared at room temperature by the electroless etching method using a specific concentration of silver nitrate and hydrofluoric acid based solution. Subsequently, these prepared SiNWs have been etched through an electrolytic process using ethanol and hydrofluoric acid based solutions to obtain porous silicon nanostructures. The reflectance and photoluminescence properties of the SiNWs based porous silicon have been studied.
Improving Productivity through Reducing MBT Application Time Using Internal Bad Block Management DFT
Authors: Sung Hyun , Shim Moon Bo , Jung Jin Sung , Eom Young Ik
Published: September 2016

Recently, storage market has been shifting from hard disk to SSD, and the importance of NAND flash memory, which plays a key role as a storage media in the SSD, is also increasing. Accordingly, in the manufacturing phase, the test cost of NAND flash memory is getting larger as the density of NAND flash memory is increasing. In this paper, we propose a scheme for DFT(Design for Testability) that can reduce the NAND flash test cost and apply it to the actual MBT(Monitoring Burn-in Test) manufacturing process to prove improvements in the manufacturing cost.
Enhancement of the Oxygen Reduction Reaction (ORR) on a PtPb Nanoparticle /TiO2/Cup-Stacked Carbon Nanotube Composite in Acidic Aqueous Solutions based on the Electronic Interaction between PtPb and TiO2
Authors: Ando Fuma , Gunji Takao , Tanabe Toyokazu , Kaneko Shingo , Takeda Tsuyoshi , Ohsaka Takeo , Matsumoto Futoshi
Published: September 2016

PtPb ordered intermetallic nanoparticles (NPs) deposited on titanium oxide (TiO2)/cup-stacked carbon nanotubes (CSCNT), PtPb NPs/TiO2/CSCNT, were prepared by synthesis of TiO2 with Ti-alkoxide under Ar atmosphere, by photodeposition of Pt NPs on the TiO2 surface of TiO2/CSCNT and by selective deposition of Pb atoms to Pt NPs with polyol method. The PtPb NPs/TiO2/CSCNT is, at the first potential cycle, inferior to bench-marked Pt NPs/carbon black (Pt/CB) in the oxygen reduction reaction (ORR) in acidic aqueous solution, whereas after 100 potential cycles between 0.3 and 1.1 V (vs. RHE), the ORR was accelerated largely when compared with the Pt/CB. The ORR activity of PtPb NPs/CB degraded with potential cycle due to the dissolution of Pb from the surface of PtPb NPs. On the other hand, the dissolution of Pb was suppressed to a lesser degree on the PtPb NPs deposited on TiO2 by the interaction between PtPb and TiO2. The dealloyed NP surface composed of the Pt atoms and the residual Pb atoms is considered to bring about the enhancement of ORR.
Sustainable Electrochemical Machining for Metal Recovery, Elimination of Waste, and Minimization of Water Usage
Authors: Skinn Brian , Lucatero Savidra , Snyder Stephen , Taylor E. J , Hall Timothy D , McCrabb Heather , Garich Holly , Inman Maria E.
Published: September 2016

This paper will discuss progress in development by Faraday of an integrated technology to recover and recycle metals from electrochemical machining (ECM). ECM is suited for low mass removal, high value-added manufacturing steps that cannot be easily performed using conventional machining, whether due to workpiece material properties, tooling limitations, or high surface integrity requirements. Sludge byproducts formed during conventional ECM processes are difficult to recover from the electrolyte, and discarding the sludge results in the loss of potentially valuable “waste” metal as well as entrained electrolyte salts and water. Results will be presented demonstrating a “Recycling ECM” technology, which is based upon patented cell designs and pulsed waveforms, targeting alloys including: C18000 copper, SAE4150 alloy steel, 316L stainless steel, and INCONEL® 718. These metals were machined in electrolyte to concentrations between 800-3500 ppm and subsequently recovered by electrowinning in solid, metallic form devoid of hydroxides/hydrated oxides, without intermediate electrolyte processing.
Modelling of Processes inside a Rechargeable Oxide Battery
Authors: Erfurt Viktoria , Braun Waldemar , Spatschek Robert , Singheiser Lorenz
Published: September 2016

To analyze the processes inside a Rechargeable Oxide Battery, a 1D model is developed to simulate the gas transport in the prevailing H2O/H2 atmosphere from the anode surface to the storage component (and reverse) as well as the gas-solid reaction inside the porous Fe/FexOy oxide microstructure. The model is implemented based on the Navier-Stokes equations and the method of finite elements using Matlab and OOPDE library. The degradation process reduces the performance of the battery along with its recyclability and lifetime. Therefore, pronounced degradation effects should be avoided as much as possible. In this respect, the model contributes to identify the critical processes in the battery and will allow further optimization with regard to the development of the battery design.
Functional and molecular identification of a TASK-1 potassium channel regulating chloride secretion through CFTR channels in the shark rectal gland: implications for cystic fibrosis
Authors: Telles Connor J. , Decker Sarah E. , Motley William W. , Peters Alexander W. , Mehr Ali Poyan , Frizzell Raymond A. , Forrest John N.
Published: September 2016

In the shark rectal gland (SRG), apical chloride secretion through CFTR channels is electrically coupled to a basolateral K+ conductance whose type and molecular identity are unknown. We performed studies in the perfused SRG with 17 K+ channel inhibitors to begin this search. Maximal chloride secretion was markedly inhibited by low-perfusate pH, bupivicaine, anandamide, zinc, quinidine, and quinine, consistent with the properties of an acid-sensitive, four-transmembrane, two-pore-domain K+ channel (4TM-K2P). Using PCR with degenerate primers to this family, we identified a TASK-1 fragment in shark rectal gland, brain, gill, and kidney. Using 5′ and 3′ rapid amplification of cDNA ends PCR and genomic walking, we cloned the full-length shark gene (1,282 bp), whose open reading frame encodes a protein of 375 amino acids that was 80% identical to the human TASK-1 protein. We expressed shark and human TASK-1 cRNA in Xenopus oocytes and characterized these channels using two-electrode voltage clamping. Both channels had identical current-voltage relationships (outward rectifying) and a reversal potential of −90 mV. Both were inhibited by quinine, bupivicaine, and acidic pH. The pKa for current inhibition was 7.75 for shark TASK-1 vs. 7.37 for human TASK-1, values similar to the arterial pH for each species. We identified this protein in SRG by Western blot and confocal immunofluorescent microscopy and detected the protein in SRG and human airway cells. Shark TASK-1 is the major K+ channel coupled to chloride secretion in the SRG, is the oldest 4TM 2P family member identified, and is the first TASK-1 channel identified to play a role in setting the driving force for chloride secretion in epithelia. The detection of this potassium channel in mammalian lung tissue has implications for human biology and disease.
Defects in brainstem neurons associated with breathing and motor function in the Mecp2R168X/Y mouse model of Rett syndrome
Authors: Johnson Christopher M. , Zhong Weiwei , Cui Ningren , Wu Yang , Xing Hao , Zhang Shuang , Jiang Chun
Published: September 2016

Rett Syndrome (RTT) is an X-linked neurodevelopmental disorder caused mostly by disruption of the MECP2 gene. Among several RTT-like mouse models, one of them is a strain of mice that carries an R168X point mutation in Mecp2 and resembles one of the most common RTT-causing mutations in humans. Although several behavioral defects have previously been found in the Mecp2R168X/Y mice, alterations in nerve cells remain unknown. Here we compare several behavioral and cellular outcomes between this Mecp2R168X/Y model and a widely used Mecp2Bird/Y mouse model. With lower body weight and shorter lifespan than their wild-type littermates, the Mecp2R168X/Y mice showed impairments of breathing and motor function. Thus we studied brainstem CO2-chemosensitive neurons and propriosensory cells that are associated with these two functions, respectively. Neurons in the locus coeruleus (LC) of both mutant strains showed defects in their intrinsic membrane properties, including changes in action potential morphology and excessive firing activity. Neurons in the mesencephalic trigeminal nucleus (Me5) of both strains displayed a higher firing response to depolarization than their wild-type littermates, likely attributable to a lower firing threshold. Because the increased excitability in LC and Me5 neurons tends to impact the excitation-inhibition balances in brainstem neuronal networks as well as their associated functions, it is likely that the defects in the intrinsic membrane properties of these brainstem neurons contribute to the breathing abnormalities and motor dysfunction. Furthermore, our results showing comparable phenotypical outcomes of Mecp2R168X/Y mice with Mecp2Bird/Y mice suggest that both strains are valid animal models for RTT research.
RACK1 is required for adipogenesis
Authors: Kong Qinghua , Gao Lan , Niu Yanfen , Gongpan Pianchou , Xu Yuhui , Li Yan , Xiong Wenyong
Published: September 2016

Adipose tissue plays a critical role in metabolic diseases and the maintenance of energy homeostasis. RACK1 has been identified as an adaptor protein involved in multiple intracellular signal transduction pathways and diseases. However, whether it regulates adipogenesis remains unknown. Here, we reported that RACK1 is expressed in 3T3-L1 cells and murine white adipose tissue and that RACK1 knockdown by shRNA profoundly suppressed adipogenesis by reducing the expression of PPAR-γ and C/EBP-β. Depletion of RACK1 increased β-catenin protein levels and activated Wnt signaling. Furthermore, RACK1 knockdown also suppressed the PI3K-Akt-mTOR-S6K signaling pathway by reducing the PI3K p85α, pAkt T473, and S6K p70. Taken together, these results demonstrate that RACK1 is a novel factor required for adipocyte differentiation by emerging Wnt/β-catenin signaling and PI3K-Akt-mTOR-S6K signaling pathway(s).
Foxp3 promoter methylation impairs suppressive function of regulatory T cells in biliary atresia
Authors: Li Kang , Zhang Xi , Yang Li , Wang Xin-xing , Yang De-hua , Cao Guo-qing , Li Shuai , Mao Yong-zhong , Tang Shao-tao
Published: September 2016

Biliary atresia (BA) is characterized by progressive inflammation of the biliary system leading to liver cirrhosis, necessitating liver transplantation in pediatric patients. Various cell types have been reported to participate in the proinflammatory response in rhesus rotavirus (RRV)-induced BA mouse models, including T helper (Th) 1, Th2, Th17, CD8+ T cells, and natural killer cells. The immune suppressive regulatory T (Treg) cells, on the contrary, were reported not to function properly. The underlying mechanism is largely unknown. Focusing on the impaired suppressive function of Treg, we found methylation status of CpG islands within the Foxp3 promoter region of Treg cells in BA patients and murine models were both increased. Moreover, by injecting 5-aza-2′-deoxycytidine (Aza) as DNA-methylation inhibitor to RRV-infected mice, BA phenotypes were alleviated. Furthermore, Treg cells isolated from “RRV+Aza”-injected mice had better suppressive function than Treg cells from mice injected with RRV only, both in vivo and ex vivo. Thus we concluded that aberrant increased methylation status of “Foxp3 promoter” in Treg cells leads to impaired Treg suppressive function, exacerbating inflammatory injury in BA.
Functional physiology of the human terminal antrum defined by high-resolution electrical mapping and computational modeling
Authors: Berry Rachel , Miyagawa Taimei , Paskaranandavadivel Niranchan , Du Peng , Angeli Timothy R. , Trew Mark L. , Windsor John A. , Imai Yohsuke , O'Grady Gregory , Cheng Leo K.
Published: September 2016

High-resolution (HR) mapping has been used to study gastric slow-wave activation; however, the specific characteristics of antral electrophysiology remain poorly defined. This study applied HR mapping and computational modeling to define functional human antral physiology. HR mapping was performed in 10 subjects using flexible electrode arrays (128–192 electrodes; 16–24 cm2) arranged from the pylorus to mid-corpus. Anatomical registration was by photographs and anatomical landmarks. Slow-wave parameters were computed, and resultant data were incorporated into a computational fluid dynamics (CFD) model of gastric flow to calculate impact on gastric mixing. In all subjects, extracellular mapping demonstrated normal aboral slow-wave propagation and a region of increased amplitude and velocity in the prepyloric antrum. On average, the high-velocity region commenced 28 mm proximal to the pylorus, and activation ceased 6 mm from the pylorus. Within this region, velocity increased 0.2 mm/s per mm of tissue, from the mean 3.3 ± 0.1 mm/s to 7.5 ± 0.6 mm/s ( P < 0.001), and extracellular amplitude increased from 1.5 ± 0.1 mV to 2.5 ± 0.1 mV ( P < 0.001). CFD modeling using representative parameters quantified a marked increase in antral recirculation, resulting in an enhanced gastric mixing, due to the accelerating terminal antral contraction. The extent of gastric mixing increased almost linearly with the maximal velocity of the contraction. In conclusion, the human terminal antral contraction is controlled by a short region of rapid high-amplitude slow-wave activity. Distal antral wave acceleration plays a major role in antral flow and mixing, increasing particle strain and trituration.
Predominant cause of prolonged low-frequency force depression changes during recovery after in situ fatiguing stimulation of rat fast-twitch muscle
Authors: Watanabe Daiki , Wada Masanobu
Published: September 2016

To investigate time-dependent changes in sarcoplasmic reticulum (SR) Ca2+ release and myofibrillar (my-) Ca2+ sensitivity during recovery from prolonged low-frequency force depression (PLFFD), rat gastrocnemius muscles were electrically stimulated in situ. After 0 h (R0), 0.5 h (R0.5), 2 h (R2), 6 h (R6), or 12 h of recovery, the superficial gastrocnemius muscles were excised and used for biochemical and skinned fiber analyses. At R0, R0.5, R2, and R6, the ratio of force at 1 Hz to that at 50 Hz was decreased in the skinned fibers. The ratio of depolarization-induced force to the maximum Ca2+-activated force (depol/Ca2+ force ratio) was utilized as an indicator of SR Ca2+ release. At R0, both the depol/Ca2+ force ratio and my-Ca2+ sensitivity were decreased. At R0.5 and R2, my-Ca2+ sensitivity was recovered, while the depol/Ca2+ force ratio remained depressed. At R6, my-Ca2+ sensitivity was decreased again, whereas the depol/Ca2+ force ratio was nearly restored. Western blot analyses demonstrated that decreased my-Ca2+ sensitivity at R6 and reduced depol/Ca2+ force ratio at R0, R0.5, and R2 were accompanied by depressions in S-glutathionylated troponin I and increases in dephosphorylated ryanodine receptor 1, respectively. These results indicate that, in the early stage of recovery, reduced SR Ca2+ release plays a primary role in the etiology of PLFFD, whereas decreased my-Ca2+ sensitivity is involved in the late stage, and suggest that S-glutathionylation of troponin I and dephosphorylation of ryanodine receptor 1 contribute, at least partly, to fatiguing contraction-induced alterations in my-Ca2+ sensitivity and SR Ca2+ release, respectively.
Reduced compensatory responses to maintain central blood volume during hypovolemic stress in women with vasovagal syncope
Authors: Skoog Johan , Zachrisson Helene , Länne Toste , Lindenberger Marcus
Published: September 2016

Although vasovagal syncope (VVS) is a common clinical condition, the underlying pathophysiology is not fully understood. A decrease in cardiac output has recently been suggested as a factor in orthostatic VVS. The aim was to investigate compensatory mechanisms to maintain central blood volume and venous return during hypovolemic stress in women with VVS. Fourteen VVS women (25.7 ± 5.0 yr) and 15 matched controls (22.8 ± 3.2 yr) were investigated. Single-step and graded lower body negative pressure (LBNP) to presyncope were used to create hypovolemic stress. Peripheral mobilization of venous blood from the arm (capacitance response and net capillary fluid absorption) and lower limb blood pooling (calf capacitance response) were evaluated using a volumetric technique. Cardiovascular responses and plasma norepinephrine (P-NE) were measured. Resting P-NE was elevated in VVS women ( P < 0.01). Despite a similar hypovolemic stimulus, the increase in P-NE was blunted ( P < 0.01) and the maximal percent increase in total peripheral resistance was reduced ( P < 0.05) during graded LBNP in VVS women. The arm capacitance response was slower ( P < 0.05) and reduced in VVS women at higher levels of LBNP ( P < 0.05). Capillary fluid absorption from extra- to intravascular space was reduced by ∼40% in VVS women ( P < 0.05). Accordingly, the reduction in cardiac output was more pronounced ( P < 0.05). In conclusion, in VVS women, mobilization of peripheral venous blood and net fluid absorption from tissue to blood during hypovolemic stress were decreased partly as a result of an attenuated vasoconstrictor response. This may seriously impede maintenance of cardiac output during hypovolemic stress and could contribute to the pathogenesis of VVS.
Functional and therapeutic importance of purinergic signaling in polycystic kidney disease
Authors: Ilatovskaya Daria V. , Palygin Oleg , Staruschenko Alexander
Published: September 2016

Polycystic kidney diseases (PKD) are a group of inherited nephropathies marked with the formation of fluid-filled cysts along the nephron. This renal disorder affects millions of people worldwide, but current treatment strategies are unfortunately limited to supportive therapy, dietary restrictions, and, eventually, renal transplantation. Recent advances in PKD management are aimed at targeting exaggerated cell proliferation and dedifferentiation to interfere with cyst growth. However, not nearly enough is known about the ion transport properties of the cystic cells, or specific signaling pathways modulating channels and transporters in this condition. There is growing evidence that abnormally elevated concentrations of adenosine triphosphate (ATP) in PKD may contribute to cyst enlargement; change in the profile of purinergic receptors may also result in promotion of cystogenesis. The current mini-review is focused on the role of ATP and associated signaling affecting ion transport properties of the renal cystic epithelia.
In situ lactate dehydrogenase activity: a novel renal cortical imaging biomarker of tubular injury?
Authors: Nielsen Per Mose , Laustsen Christoffer , Bertelsen Lotte Bonde , Qi Haiyun , Mikkelsen Emmeli , Kristensen Marie Louise Vindvad , Nørregaard Rikke , Stødkilde-Jørgensen Hans
Published: September 2016

Renal ischemia-reperfusion injury is the state of which a tissue experiences injury after a phase of restrictive blood supply and recirculation. Ischemia-reperfusion injury (I/R-I) is a leading cause of acute kidney injury (AKI) in several disease states, including kidney transplantation, sepsis, and hypovolemic shock. The most common methods to evaluate AKI are creatinine clearance, plasma creatinine, blood urea nitrogen, or renal histology. However, currently, there are no precise methods to directly assess renal injury state noninvasively. Hyperpolarized13C-pyruvate MRI enables noninvasive accurate quantification of the in vivo conversion of pyruvate to lactate, alanine, and bicarbonate. In the present study, we investigated the in situ alterations of metabolic conversion of pyruvate to lactate, alanine, and bicarbonate in a unilateral I/R-I rat model with 30 min and 60 min of ischemia followed by 24 h of reperfusion. The pyruvate conversion was unaltered compared with sham in the 30 min I/R-I group, while a significant reduced metabolic conversion was found in the postischemic kidney after 60 min of ischemia. This indicates that after 30 min of ischemia, the kidney maintains normal metabolic function in spite of decreased kidney function, whereas the postischemic kidney after 60 min of ischemia show a generally reduced metabolic enzyme activity concomitant with a reduced kidney function. We have confidence that these findings can have a high prognostic value in prediction of kidney injury and the outcome of renal injury.
A Formula for the Energy of Circulant Graphs with Two Generators
Authors: Louis Justine
Published: September 2016

We derive closed formulas for the energy of circulant graphs generated by1andγ, whereγ⩾2is an integer. We also find a formula for the energy of the complete graph without a Hamilton cycle.
Metastatic Gastrointestinal Adenocarcinoma with Osteoblastic Activity: A Case Report of Esophageal and Colonic Primaries
Authors: Lowenthal Brett Matthew , Shabaik Ahmed S. , Valasek Mark A.
Published: September 2016

Adenocarcinoma with osteoblastic metastases is classically seen in prostate, breast, and lung primaries. Less common primary sites include thyroid, kidney, and stomach. We present two cases of primary gastrointestinal adenocarcinoma with metastatic osteoblastic activity from two previously unreported sites. The first case represents an esophageal adenocarcinoma arising in a background of intestinal metaplasia that metastasized with osteoblastic activity to the deltoid muscle. The second case demonstrates a Stage IV sigmoid colon adenocarcinoma with osteoblastic metastases to the liver and lymph nodes. The findings indicate that metastases from various gastrointestinal primary adenocarcinomas can have prominent bone formation.
Use of Zoledronic Acid in Paediatric Craniofacial Fibrous Dysplasia
Authors: Di Pede Chiara , Congedi Sabrina , Rossin Sara , Divisic Antuan , De Gregorio Alesandra , Agosto Caterina , Catalano Igor , Mazza Alessandro , Sartori Leonardo , Masiero Stefano , Benini Franca
Published: September 2016

We describe a case of a paediatric patient affected by mandibular fibrous dysplasia (FD) with severe and chronic pain who was successfully treated with zoledronic acid (ZOL): a third-generation bisphosphonate. Further research is needed to assess its safety and efficacy as a treatment option for FD in the paediatric population.
Vascular Transdifferentiation in the CNS: A Focus on Neural and Glioblastoma Stem‐Like Cells
Authors: Guelfi Sophie , Duffau Hugues , Bauchet Luc , Rothhut Bernard , Hugnot Jean-Philippe
Published: September 2016

Glioblastomas are devastating and extensively vascularized brain tumors from which glioblastoma stem‐like cells (GSCs) have been isolated by many groups. These cells have a high tumorigenic potential and the capacity to generate heterogeneous phenotypes. There is growing evidence to support the possibility that these cells are derived from the accumulation of mutations in adult neural stem cells (NSCs) as well as in oligodendrocyte progenitors. It was recently reported that GSCs could transdifferentiate into endothelial‐like and pericyte‐like cells both in vitro and in vivo, notably under the influence of Notch and TGFβ signaling pathways. Vascular cells derived from GBM cells were also observed directly in patient samples. These results could lead to new directions for designing original therapeutic approaches against GBM neovascularization but this specific reprogramming requires further molecular investigations. Transdifferentiation of nontumoral neural stem cells into vascular cells has also been described and conversely vascular cells may generate neural stem cells. In this review, we present and discuss these recent data. As some of them appear controversial, further validation will be needed using new technical approaches such as high throughput profiling and functional analyses to avoid experimental pitfalls and misinterpretations.