bluuebunny/crossref_metadata_2025 huggingface dataset:
BMPR2 inhibition induced apoptosis and autophagy via destabilization of XIAP in human chondrosarcoma cells
Authors: Jiao G , Guo W , Ren T , Lu Q , Sun Y , Liang W , Ren C , Yang K , Sun K
Published: December 2014

Bone morphogenetic proteins (BMPs) are multifunctional proteins, and their receptors (BMPRs) have crucial roles in the process of signaling. However, their function in cancer is somewhat inconsistent. It has been demonstrated that more prevalent expression of bone morphogenetic protein receptor 2 (BMPR2) has been detected in dedifferentiated chondrosarcomas than conventional chondrosarcomas. Here, we find that BMPR2 inhibition induces apoptosis and autophagy of chondrosarcoma. We found that BMPR2 expression was correlated with the clinicopathological features of chondrosarcomas, and could predict the treatment outcome. Knockdown of BMPR2 by small interfering RNA results in growth inhibition in chondrosarcoma cells. Silencing BMPR2 promoted G2/M cell cycle arrest, induced chondrosarcoma cell apoptosis through caspase-3-dependent pathway via repression of X-linked inhibitor of apoptosis protein (XIAP) and induced autophagy of chondrosarcoma cells via XIAP-Mdm2-p53 pathway. Inhibition of autophagy induced by BMPR2 small interfering RNA (siBMPR2) sensitized chondrosarcoma cells to siBMPR2-induced apoptotic cell death, suggesting that autophagy has a protective role for chondrosarcoma cells in context of siBMPR2-induced apoptotic cell death. In vivo tumorigenicity assay in mice indicated that inhibition of BMPR2 reduced tumor growth. Taken together, our results suggest that BMPR2 has a significant role in the tumorigenesis of chondrosarcoma, and could be an important prognostic marker for chondrosarcoma. BMPR2 inhibition could eventually provide a promising therapy for chondrosarcoma treatment.
Assembling programmable FRET-based photonic networks using designer DNA scaffolds
Authors: Buckhout-White Susan , Spillmann Christopher M , Algar W. Russ , Khachatrian Ani , Melinger Joseph S. , Goldman Ellen R. , Ancona Mario G. , Medintz Igor L.
Published: December 2014

DNA demonstrates a remarkable capacity for creating designer nanostructures and devices. A growing number of these structures utilize Förster resonance energy transfer (FRET) as part of the device's functionality, readout or characterization, and, as device sophistication increases so do the concomitant FRET requirements. Here we create multi-dye FRET cascades and assess how well DNA can marshal organic dyes into nanoantennae that focus excitonic energy. We evaluate 36 increasingly complex designs including linear, bifurcated, Holliday junction, 8-arm star and dendrimers involving up to five different dyes engaging in four-consecutive FRET steps, while systematically varying fluorophore spacing by Förster distance (R0). Decreasing R0 while augmenting cross-sectional collection area with multiple donors significantly increases terminal exciton delivery efficiency within dendrimers compared with the first linear constructs. Förster modelling confirms that best results are obtained when there are multiple interacting FRET pathways rather than independent channels by which excitons travel from initial donor(s) to final acceptor.
TRPA1 is essential for the vascular response to environmental cold exposure
Authors: Aubdool Aisah A. , Graepel Rabea , Kodji Xenia , Alawi Khadija M. , Bodkin Jennifer V. , Srivastava Salil , Gentry Clive , Heads Richard , Grant Andrew D. , Fernandes Elizabeth S. , Bevan Stuart , Brain Susan D.
Published: December 2014

The cold-induced vascular response, consisting of vasoconstriction followed by vasodilatation, is critical for protecting the cutaneous tissues against cold injury. Whilst this physiological reflex response is historic knowledge, the mechanisms involved are unclear. Here by using a murine model of local environmental cold exposure, we show that TRPA1 acts as a primary vascular cold sensor, as determined through TRPA1 pharmacological antagonism or gene deletion. The initial cold-induced vasoconstriction is mediated via TRPA1-dependent superoxide production that stimulates α2C-adrenoceptors and Rho-kinase-mediated MLC phosphorylation, downstream of TRPA1 activation. The subsequent restorative blood flow component is also dependent on TRPA1 activation being mediated by sensory nerve-derived dilator neuropeptides CGRP and substance P, and also nNOS-derived NO. The results allow a new understanding of the importance of TRPA1 in cold exposure and provide impetus for further research into developing therapeutic agents aimed at the local protection of the skin in disease and adverse climates.
The combination of artificial neural networks and synchrotron radiation-based infrared micro-spectroscopy for a study on the protein composition of human glial tumors
Authors: Surowka A. D. , Adamek D. , Szczerbowska-Boruchowska M.
Published: December 2014

Protein-related changes associated with the development of human brain gliomas are of increasing interest in modern neuro-oncology.
Preparative separation of isoflavones in plant extract of Pueraria lobata by high performance counter-current chromatography
Authors: Li Bo , Li Li , Zhao Anqi , Han Binhua , Fan Yajun , Liu Chunming , Liu Jianjun
Published: December 2014

In this study, five isoflavones, puerarin, daidzin, daidzein, 3′-hydroxy-puerarin and 3′-methoxy-puerarin were isolated and purified simultaneously from Pueraria lobata for the first time by high performance counter-current chromatography (HPCCC) in 200 min in a run.
Near infrared activation of an anticancer PtIV complex by Tm-doped upconversion nanoparticles
Authors: Ruggiero Emmanuel , Hernández-Gil Javier , Mareque-Rivas Juan C. , Salassa Luca
Published: December 2014

The PtIV complex cis,cis,trans-[Pt(NH3)2(Cl)2(O2CCH2CH2CO2H)2] is photoactivated by near infrared light (980 nm) using NaYF4:Yb3+/Tm3+@NaYF4 core–shell upconversion nanoparticles.
Mass spectrometry imaging of fingerprint sweat on nanostructured silicon
Authors: Guinan T. , Della Vedova C. , Kobus H. , Voelcker N. H.
Published: December 2014

Desorption ionisation on porous silicon mass spectrometry imaging (DIOS-MSI) was used on fingerprints to map the distribution of exogenous and endogenous molecules present in sweat.
A novel fluoro-chromogenic click reaction for the labelling of proteins and nanoparticles with near-IR theranostic agents
Authors: Planas Oriol , Gallavardin Thibault , Nonell Santi
Published: December 2014

Binding of red-absorbing porphycene isothiocyanates to proteins and nanoparticles leads to near-IR fluorescent and photosensitising conjugates.
Switching adhesion and friction by light using photosensitive guest–host interactions
Authors: Blass Johanna , Bozna Bianca L. , Albrecht Marcel , Krings Jennifer A. , Ravoo Bart Jan , Wenz Gerhard , Bennewitz Roland
Published: December 2014

Friction and adhesion between two β-cyclodextrin functionalized surfaces can be switched reversibly by external light stimuli. The interaction is mediated by complexation with ditopic azobenzene guest molecules.
Pressure-induced molten globule state of human acetylcholinesterase: structural and dynamical changes monitored by neutron scattering
Authors: Marion J. , Trovaslet M. , Martinez N. , Masson P. , Schweins R. , Nachon F. , Trapp M. , Peters J.
Published: December 2014

We used neutron scattering to study the effects of high hydrostatic pressure on the structure and dynamics of human acetylcholinesterase (hAChE).
Ab initio multiple cloning simulations of pyrrole photodissociation: TKER spectra and velocity map imaging
Authors: Makhov Dmitry V. , Saita Kenichiro , Martinez Todd J. , Shalashilin Dmitrii V.
Published: December 2014

We report a detailed computational simulation of the photodissociation of pyrrole using the ab initio Multiple Cloning (AIMC) method implemented within MOLPRO.
Reporter-encapsulated liposomes on graphene field effect transistors for signal enhanced detection of physiological enzymes
Authors: Chen Hu , Lim Seng Koon , Chen Peng , Huang Jingfeng , Wang Yi , Palaniappan Alagappan , Platt Mark , Liedberg Bo , Tok Alfred Iing Yoong
Published: December 2014

A novel approach for enzymatic assay using reporter-encapsulated liposomes on graphene field effect transistors (FET) is proposed.
Wavelength- and efficiency-tunable plasmon-induced charge separation by the use of Au–Ag alloy nanoparticles
Authors: Nishi Hiroyasu , Torimoto Tsukasa , Tatsuma Tetsu
Published: December 2014

TiO2 electrodes modified with Au–Ag alloy nanoparticles exhibit photocurrents based on plasmon-induced charge separation (PICS).
Constrained control landscape for population transfer in a two-level system
Authors: Moore Tibbetts Katharine , Rabitz Herschel
Published: December 2014

Controlling population transfer in a two-level quantum system reveals a landscape with a rich structure containing highly connected optimal regions.
Pnicogen and hydrogen bonds: complexes between PH3X+and PH2X systems
Authors: Alkorta Ibon , Elguero José , Grabowski Sławomir J.
Published: December 2014

The charge-assisted complexes between PH3X+and PH2X show three potential minima structures, the pnicogen bonded (I) one being the most stable.
Novel nanoparticle/enzyme biosilicified nanohybrids for advanced heterogeneously catalyzed protocols
Authors: Garcia Carolina , Junior Ivaldo I. , de Souza Rodrigo O. M. A. , Luque Rafael
Published: December 2014

Novel bio-nanohybrids based on room temperature one-pot synthesized lipase-nanoparticle systems were developed and characterized in this work, with subsequent investigations of their catalytic activities and stability as compared to the free enzymes.
Adipic acid production from lignin
Authors: Vardon Derek R. , Franden Mary Ann , Johnson Christopher W. , Karp Eric M. , Guarnieri Michael T. , Linger Jeffrey G. , Salm Michael J. , Strathmann Timothy J. , Beckham Gregg T.
Published: December 2014

Biological funneling is used to convert lignin-derived species to muconic acid, which is separated and catalytically upgraded to adipic acid.
Selective aerobic oxidation of the biomass-derived precursor 5-hydroxymethylfurfural to 2,5-furandicarboxylic acid under mild conditions over a magnetic palladium nanocatalyst
Authors: Zhang Zehui , Zhen Judun , Liu Bing , Lv Kangle , Deng Kejian
Published: December 2014

High yield of 2,5-furandicarboxylic acid was achieved from the aerobic oxidation of 5-hydroxymethylfurfural over a magnetic palladium nanocatalyst.
Direct detection and isotope analysis of individual particles in suspension by single particle mode MC-ICP-MS for nuclear safety
Authors: Yongyang Su , Wei Wang , Zhiming Li , Hu Deng , Guoqing Zhou , Jiang Xu , Xiangjun Ren
Published: December 2014

Direct detection and precise isotope analysis of individual particles in suspension by single particle mode MC-ICP-MS.
Microfluidic devices for imaging neurological response of Drosophila melanogaster larva to auditory stimulus
Authors: Ghaemi Reza , Rezai Pouya , Iyengar Balaji G. , Selvaganapathy Ponnambalam Ravi
Published: December 2014

The central nervous system of a liveDrosophilalarva was imaged and its response to auditory stimulus has been characterized.
Copper hydrotris(3,5-diphenylpyrazolyl)borate dithiocarbamates: mimicking green copper proteins
Authors: Harding David J. , Phonsri Wasinee , Harding Phimphaka , Sirirak Jitnapa , Tangtirungrotechai Yuthana , Webster Richard D. , Adams Harry
Published: December 2014

Three new copper hydrotris(pyrazolyl)borate dithiocarbamate complexes [TpPh2Cu(dtc)] which mimic green copper proteins are reported.
Simultaneous direct detection of Shiga-toxin producing Escherichia coli (STEC) strains by optical biosensing with oligonucleotide-functionalized gold nanoparticles
Authors: Quintela Irwin A. , de los Reyes Benildo G. , Lin Chih-Sheng , Wu Vivian C. H.
Published: December 2014

We report here a simultaneous and direct detection of foodborne pathogens by an optical biosensing method using oligonucleotide-functionalized gold nanoparticles.
An amplified electrochemiluminescent aptasensor using Au nanoparticles capped by 3,4,9,10-perylene tetracarboxylic acid-thiosemicarbazide functionalized C60 nanocomposites as a signal enhancement tag
Authors: Ma Meng-Nan , Zhang Xia , Zhuo Ying , Chai Ya-Qin , Yuan Ruo
Published: December 2014

A novel electrochemiluminescent aptasensor for thrombin detection.
Mass spectrometric investigation of the roles of several chemical intermediates in diamond synthesis
Authors: Fan L. S. , Zhou Y. S. , Wang M. X. , Gao Y. , Xiong W. , Liu Y. , Lu Y. , Silvain J. F. , Lu Y. F.
Published: December 2014

Mass spectrometric studies were performed to investigate several key chemical intermediates and identify their roles in diamond synthesis in a C2H4/C2H2/O2 combustion-flame chemical vapour deposition process.
Graphene oxide wrapped hierarchical porous carbon–sulfur composite cathode with enhanced cycling and rate performance for lithium sulfur batteries
Authors: Liu Shuangke , Xie Kai , Li Yujie , Chen Zhongxue , Hong Xiaobin , Zhou Liangjun , Yuan Junfei , Zheng Chunman
Published: December 2014

A graphene oxide sheet wrapped hierarchical porous carbon–sulfur (HPC–S@GO) composite was designed by a two-step method to improve the lithium sulfur battery performance.
A green and one-pot synthesis of benzo[g]chromene derivatives through a multi-component reaction catalyzed by lipase
Authors: Yang Fengjuan , Wang Haoran , Jiang Liyan , Yue Hong , Zhang Hong , Wang Zhi , Wang Lei
Published: December 2014

Lipase-catalyzed synthesis of benzo[g]chromene derivatives.
Lipid composition: a “key factor” for the rational manipulation of the liposome–protein corona by liposome design
Authors: Caracciolo G. , Pozzi D. , Capriotti A. L. , Cavaliere C. , Piovesana S. , Amenitsch H. , Laganà A.
Published: December 2014

When liposomes are exposed to biological fluids, a dynamic protein coating immediately covers them forming a ‘protein corona’. Those proteins can interact with receptors (over)expressed on the plasma membrane of target cells bringing the liposomes to their final destination.
Pushing the limits for enzyme-based membrane-less hydrogen fuel cells – achieving useful power and stability
Authors: Xu Lang , Armstrong Fraser A.
Published: December 2014

The festive Hydrogen House, powered by a hydrogen–air mixture using an enzyme fuel cell.
Polybenzoxazine-based nitrogen-containing porous carbons for high-performance supercapacitor electrodes and carbon dioxide capture
Authors: Wan Liu , Wang Jianlong , Sun Yahui , Feng Chong , Li Kaixi
Published: December 2014

Nitrogen-containing porous carbons were synthesized from a novel polybenzoxazine for high-performance supercapacitor electrode and carbon dioxide capture.
Synthesis of porous In2O3 microspheres as a sensitive material for early warning of hydrocarbon explosions
Authors: Cao Yang , Zhao Jun , Zou Xiaoxin , Jin Pan-Pan , Chen Hui , Gao Ruiqin , Zhou Li-Jing , Zou Yong-Cun , Li Guo-Dong
Published: December 2014

We report the template-free synthesis of porous nanoparticle-assembled In2O3 microspheres that can serve as a highly sensitive material for the detection of C1–C3 hydrocarbons.
Formation of uniform hollow nanocages with heteroatom-doped MCM-41 structures
Authors: Chen Jiazhi , Lu Fang , Xu Jie
Published: December 2014

Monodispersed heteroatom-doped hollow nanocages with MCM-41 structures are synthesized by reacting nanosized MCM-41 seeds with in situ coated heteroatomic species.
High yield of renewable hexanes by direct hydrolysis–hydrodeoxygenation of cellulose in an aqueous phase catalytic system
Authors: Liu Yong , Chen Lungang , Wang Tiejun , Zhang Xinghua , Long Jinxing , Zhang Qi , Ma Longlong
Published: December 2014

In aqueous phosphoric acid, cellulose was efficiently converted into hexanes using a Ru/C catalyst combined with layered compounds. The layered compounds showed powerful inhibition of isosorbide, the side-product for the cellulose-to-hexanes route.
Supported copper and cobalt oxides on activated carbon for simultaneous oxidation of toluene and cyclohexane in air
Authors: Zabihi Mohammad , Khorasheh Farhad , Shayegan Jalal
Published: December 2014

Dispersed nano mixed copper–cobalt oxides bimetallic catalysts were prepared by deposition–precipitation method for simultaneous and complete oxidation of toluene and cyclohexane.
Asymmetric traps array for particle transport
Authors: Lee Jaesung , Burns Mark A.
Published: December 2014

The asymmetric trap composed of three obstacles shows flow direction-dependent trap/particle interaction.
New insights into the mesophase transformation of ethane-bridged PMOs by the influence of different counterions under basic conditions
Authors: Lin Feng , Meng Xiangyan , Kukueva Elena , Mertens Myrjam , Van Doorslaer Sabine , Bals Sara , Cool Pegie
Published: December 2014

The counterions are of crucial importance in determining the mesostructure and morphology of ethane-bridged PMO materials synthesized under basic conditions.
Fabrication of glass-based microfluidic devices with dry film photoresists as pattern transfer masks for wet etching
Authors: Zhang Lei , Wang Wei , Ju Xiao-Jie , Xie Rui , Liu Zhuang , Chu Liang-Yin
Published: December 2014

A simple, cheap and rapid method is developed to fabricate glass microfluidic devices with dry film photoresist as pattern transfer masks for wet etching, which provides an efficient approach for mass-production of glass microchips.
Correction: Laser-induced cross-linking GFP-AcmA′ bioprobe for screening Gram-positive bacteria on a biochip
Authors: Lin Chuen-Fu , Lin Che-Kuan , Liu Yi-Jui , Chiang Chung-Han , Pan Ming-Jeng , Baldeck Patrice L. , Lin Chih-Lang
Published: December 2014

Correction for ‘Laser-induced cross-linking GFP-AcmA′ bioprobe for screening Gram-positive bacteria on a biochip’ by Chuen-Fu Lin et al., RSC Adv., 2014, 4, 62882–62887.
Correction: Antimicrobial effects of silver deposited on nanolayered manganese oxide
Authors: Najafpour Mohammad Mahdi , Zahraei Ali , Amini Emad , Ahari-Mostafavi Mohammad Mahdi , Kompany-Zareh Mohsen
Published: December 2014

Correction for ‘Antimicrobial effects of silver deposited on nanolayered manganese oxide’ by Mohammad Mahdi Najafpour et al., RSC Adv., 2014, 4, 64688–64691.
Internal organization of macromonomers and dendronized polymers based on thiophene dendrons
Authors: Córdova-Mateo Esther , Bertran Oscar , Schlüter A. Dieter , Kröger Martin , Alemán Carlos
Published: December 2014

Multi-scale simulations reveal the organization of macromonomers and dendronized polymers derived from all-thiophene dendrons attached to a phenyl core.
Thermo-moldable self-healing commodity plastics with heat resisting and oxygen-insensitive healant capable of room temperature redox cationic polymerization
Authors: Zhu Dong Yu , Guo Jian Wei , Cao Guang Sheng , Qiu Wen Lian , Rong Min Zhi , Zhang Ming Qiu
Published: December 2014

By using a novel healing chemistry of redox cationic polymerization, polystyrene with IBH/GMA capsules and NaBH4 particles molded via hot compression is proved to be self-healable at room temperature in air.
A solar-driven photocatalytic fuel cell with dual photoelectrode for simultaneous wastewater treatment and hydrogen production
Authors: Wu Zhongyi , Zhao Guohua , Zhang Yajun , Liu Jian , Zhang Ya-nan , Shi Huijie
Published: December 2014

A solar-driven dual photoelectrode photocatalytic fuel cell (PFC) based on n-type semiconductor photoanode and p-type semiconductor photocathode is reported for wastewater treatment with simultaneous hydrogen production.
Compact controlled reception pattern antenna for interference mitigation tasks of global navigation satellite system receivers
Authors: Alshrafi Wasim , Engel Ulrich , Bertuch Thomas
Published: December 2014

In this study, a novel compact controlled reception pattern antenna for global navigation satellite system (GNSS) applications is presented. Details of the design and the fabrication are given together with measurement results. The miniaturisation has been achieved by employing a five‐element polarimetric array approach, resulting in anti‐jamming capabilities for many applications where the antenna size is a major constraint. The antenna has a relatively wide bandwidth around the GNSS L1 band which contains many different GNSS signals. The anti‐jamming performance of the antenna with respect to differently polarised jammers as well as its positioning capability are investigated.
Deterioration in effective thermal conductivity of aqueous magnetic nanofluids
Authors: Altan Cem L. , Gurten Berna , Sommerdijk Nico A. J. M. , Bucak Seyda
Published: December 2014

Common heat transfer fluids have low thermal conductivities, which decrease their efficiency in many applications. On the other hand, solids have much higher thermal conductivity values. Previously, it was shown that the addition of different nanoparticles to various base fluids increases the thermal conductivity of the carrier fluid remarkably. However, there are limited studies that focus on the thermal conductivity of magnetic fluids. In this study, thermal conductivity of magnetic nanofluids composed of magnetite nanoparticles synthesized via co-precipitation and thermal decomposition methods is investigated. Results showed that the addition of magnetite nanoparticles decreased the thermal conductivity of water and ethylene glycol. This decrease was found to increase with increasing particle concentration and to be independent of the synthesis method, the type of surfactant, and the interfacial thermal resistance.
Interplay of anisotropy in shape and interactions in charged platelet suspensions
Authors: Jabbari-Farouji Sara , Weis Jean-Jacques , Davidson Patrick , Levitz Pierre , Trizac Emmanuel
Published: December 2014

Motivated by the intriguing phase behavior of charged colloidal platelets, we investigate the structure and dynamics of charged repulsive disks by means of Monte Carlo simulations. The electrostatic interactions are taken into account through an effective two-body potential, obtained within the nonlinear Poisson-Boltzmann formalism, which has the form of anisotropic screened Coulomb potential. Recently, we showed that the original intrinsic anisotropy of the electrostatic potential in competition with excluded volume effects leads to a rich phase behavior that not only includes various liquid-crystalline phases but also predicts the existence of novel structures composed of alternating nematic-antinematic sheets. Here, we examine the structural and dynamical signatures of each of the observed structures for both translational and rotational degrees of freedom. Finally, we discuss the influence of effective charge value and our results in relation to experimental findings on charged platelet suspensions.
Wake effects on drift in two-dimensional inviscid incompressible flows
Authors: Melkoumian Sergei , Protas Bartosz
Published: December 2014

This investigation analyzes the effect of vortex wakes on the Lagrangian displacement of particles induced by the passage of an obstacle in a two-dimensional incompressible and inviscid fluid. In addition to the trajectories of individual particles, we also study their drift and the corresponding total drift areas in the Föppl and Kirchhoff potential flow models. Our findings, which are obtained numerically and in some regimes are also supported by asymptotic analysis, are compared to the wakeless potential flow which serves as a reference. We show that in the presence of the Föppl vortex wake, some of the particles follow more complicated trajectories featuring a second loop. The appearance of an additional stagnation point in the Föppl flow is identified as a source of this effect. It is also demonstrated that, while the total drift area increases with the size of the wake for large vortex strengths, it is actually decreased for small circulation values. On the other hand, the Kirchhoff flow model is shown to have an unbounded total drift area. By providing a systematic account of the wake effects on the drift, the results of this study will allow for more accurate modeling of hydrodynamic stirring.
Time-resolved radiation chemistry: Dynamics of electron attachment to uracil following UV excitation of iodide-uracil complexes
Authors: King Sarah B. , Yandell Margaret A. , Stephansen Anne B. , Neumark Daniel M.
Published: December 2014

Electron attachment to uracil was investigated by applying time-resolved photoelectron imaging to iodide-uracil (I–U) complexes. In these studies, an ultraviolet pump pulse initiated charge transfer from the iodide to the uracil, and the resulting dynamics of the uracil temporary negative ion were probed. Five different excitation energies were used, 4.00 eV, 4.07 eV, 4.14 eV, 4.21 eV, and 4.66 eV. At the four lowest excitation energies, which lie near the vertical detachment energy of the I–U complex (4.11 eV), signatures of both the dipole bound (DB) as well as the valence bound (VB) anion of uracil were observed. In contrast, only the VB anion was observed at 4.66 eV, in agreement with previous experiments in this higher energy range. The early-time dynamics of both states were highly excitation energy dependent. The rise time of the DB anion signal was ∼250 fs at 4.00 eV and 4.07 eV, ∼120 fs at 4.14 eV and cross-correlation limited at 4.21 eV. The VB anion rise time also changed with excitation energy, ranging from 200 to 300 fs for excitation energies 4.00–4.21 eV, to a cross-correlation limited time at 4.66 eV. The results suggest that the DB state acts as a “doorway” state to the VB anion at 4.00–4.21 eV, while direct attachment to the VB anion occurs at 4.66 eV.
Magnetic properties of BaTiO3/La0.7Sr0.3MnO3 thin films integrated on Si(100)
Authors: Singamaneni Srinivasa Rao , Fan Wu , Prater J. T. , Narayan J.
Published: December 2014

Two-phase multiferroic heterostructures composed of room-temperature ferroelectric BaTiO3 (BTO) and ferromagnetic La0.7Sr0.3MnO3 (LSMO) epitaxial thin films were grown on technologically important substrate Si (100). Bilayers of BTO/LSMO thin films display ferromagnetic Curie transition temperatures of ∼350 K, close to the bulk value, which are independent of BTO films thickness in the range of 25–100 nm. Discontinuous magnetization jumps associated with BTO structural transitions were suppressed in M(T) curves, probably due to substrate clamping effect. Interestingly, at cryogenic temperatures, the BTO/LSMO structure with BTO layer thickness of 100 nm shows almost 2-fold higher magnetic coercive field, 3-fold reduction in saturation magnetization, and improved squareness compared to the sample without BTO. We believe that the strong in-plane spin pinning of the ferromagnetic layer induced by BTO layer at BTO/LSMO interface could cause such changes in magnetic properties. This work forms a significant step forward in the integration of two-phase multiferroic heterostructures for CMOS applications.
Detrapping of tungsten nanoparticles in a direct-current argon glow discharge
Authors: Couëdel L. , Kumar K. Kishor , Arnas C.
Published: December 2014

Nanoparticles are grown from the sputtering of a tungsten cathode in a direct current argon glow discharge. Laser light scattering of a vertical laser sheet going through the plasma reveals that the dust particle cloud is compressed and pushed towards the anode during the discharge. Scanning electron microscopy images of substrates exposed to the plasma for given durations show that dust particles are continuously falling down on the anode during the discharge. These observations are explained by the fact that the electrostatic force at the negative glow-anode sheath boundary cannot balance the ion drag, gravity, and thermophoresis forces for particles of more than a few tens of nanometres in diameter.
Effect of niobium addition on the martensitic transformation and magnetocaloric effect in low hysteresis NiCoMnSn magnetic shape memory alloys
Authors: Emre Baris , Bruno Nickolaus M. , Yuce Emre Suheyla , Karaman Ibrahim
Published: December 2014

The effect of Nb substitution for Ni in Ni45Co5Mn40Sn10 magnetic shape memory alloys on their magnetic properties, martensitic transformation characteristics, transformation hysteresis, and magnetocaloric properties was studied using wavelength-dispersive X-ray spectroscopy, differential scanning calorimetry, and the temperature and field dependence of the magnetization. Ni45Co5Mn40Sn10 alloy has a very low transformation hysteresis; however, the martensitic transformation temperatures are notably above room temperature, which is not desirable for magnetic refrigeration applications. In this study, small quantities of Nb substitution were shown to drastically shift the transformation temperatures to lower temperatures, at a rate of 68 K/at. % Nb, which is needed for household refrigeration. The austenite Curie temperature also decreased with increasing Nb content. However, a decrease in the latent heat of the martensitic transition was observed, which negatively affects the magnetic field-induced adiabatic temperature change capability. Still, the relatively large transformation entropy and the low transformation hysteresis make the Nb-doped Ni45Co5Mn40Sn10 alloys potential candidates for solid state refrigeration near room temperature.
Probing the electronic and vibrational structure of Au2Al2− and Au2Al2 using photoelectron spectroscopy and high resolution photoelectron imaging
Authors: Lopez Gary V. , Czekner Joseph , Jian Tian , Li Wei-Li , Yang Zheng , Wang Lai-Sheng
Published: December 2014

The electronic and vibrational structures of Au2Al2− and Au2Al2 have been investigated using photoelectron spectroscopy (PES), high-resolution photoelectron imaging, and theoretical calculations. Photoelectron spectra taken at high photon energies with a magnetic-bottle apparatus reveal numerous detachment transitions and a large energy gap for the neutral Au2Al2. Vibrationally resolved PE spectra are obtained using high-resolution photoelectron imaging for the ground state detachment transition of Au2Al2− at various photon energies (670.55−843.03 nm). An accurate electron affinity of 1.4438(8) eV is obtained for the Au2Al2 neutral cluster, as well as two vibrational frequencies at 57 ± 8 and 305 ± 13 cm−1. Hot bands transitions yield two vibrational frequencies for Au2Al2− at 57 ± 10 and 144 ± 12 cm−1. The obtained vibrational and electronic structure information is compared with density functional calculations, unequivocally confirming that both Au2Al2− and Au2Al2 possess C2v tetrahedral structures.
Magnetic separation of Dy(III) ions from homogeneous aqueous solutions
Authors: Pulko B. , Yang X. , Lei Z. , Odenbach S. , Eckert K.
Published: December 2014

The possibility to enrich paramagnetic dysprosium(III) ions in a magnetic field gradient is proved by means of interferometry, which may open the route for a magnetic separation of rare earth ions from aqueous solutions. The separation dynamics are studied for three different concentrations of DyCl3 and compared with those found recently in a sulphate solution of the 3d ion Mn(II). In view of the similar-sized hydration spheres for Dy(III) and Mn(II), the slower separation dynamics in DyCl3 is attributed to both a higher densification coefficient and the strong impact of Brownian motion due to the absence of ion-pair clusters.
Excited eigenmodes in magnetic vortex states of soft magnetic half-spheres and spherical caps
Authors: Yoo Myoung-Woo , Lee Jae-Hyeok , Kim Sang-Koog
Published: December 2014

We studied the magnetization dynamics of excitation modes in special geometrical confinements of soft magnetic half-spheres and spherical caps in magnetic vortex states using finite-element micromagnetic numerical calculations. We found additional fine features of the zeroth- and first-order gyrotropic modes and asymmetric m = +1 and m = −1 azimuthal spin-wave modes, which detailed information is unobtainable from two-dimensional mesh-cell based numerical calculations. Moreover, we examined the perpendicular bias field dependence of the excited eigenmodes, which data provide for an efficient means of control over the excited modes. Such numerical calculations offer additional details or new underlying physics on dynamic features in arbitrary-shape magnetic nano-elements such as half-spheres and spherical caps in magnetic vortex states.
Positive magnetoresistance in Ca-doped cobaltites
Authors: Zhou S. M. , Li Y. , Guo Y. Q. , Zhao J. Y. , Shi L.
Published: December 2014

Transport properties of polycrystalline La1−xCaxCoO3 (0.10 ≤ x ≤ 0.25) are systemically studied in this work. Three types of magnetoresistance (MR) effects are found in the Ca-doped cobaltites. Two negative MRs appear around high-temperature ferromagnetic transition and at low temperatures, which correspond to the conventional MR due to the field-induced suppression of spin-disorder scattering and the intergranular giant-MR due to spin-dependent transport between the ferromagnetic clusters, respectively. More interestingly, another exotic positive MR emerges at intermediate temperature region, which had not been previously reported in Sr- and Ba-doped cobaltites. It is found that this positive MR is associated with an abnormally magnetic transition and increases with the increase of x. For x = 0.25, the MR at low temperatures is dominated by the positive one, which is isotropic and nearly linear with the magnetic field. The possible origin of the positive MR in the Ca-doped cobaltites is discussed.
Perturbation analysis of ionization oscillations in Hall effect thrusters
Authors: Hara Kentaro , Sekerak Michael J. , Boyd Iain D. , Gallimore Alec D.
Published: December 2014

A perturbation analysis of ionization oscillations, which cause low frequency oscillations of the discharge plasma, in Hall effect thrusters is presented including the electron energy equation in addition to heavy-species transport. Excitation and stabilization of such oscillations, often called the breathing mode, are discussed in terms of the growth rate obtained from the linear perturbation equations of the discharge plasma. The instability induced from the ionization occurs only when the perturbation in the electron energy is included while the neutral atom flow contributes to the damping of the oscillation. Effects of the electron energy loss mechanisms such as wall heat loss, inelastic collisions, and convective heat flux are discussed. It is shown that the ionization oscillations can be damped when the electron transport is reduced and the electron temperature increases so that the energy loss to the wall stabilizes the ionization instability.
Filamentary structure of plasma produced by compression of puffing deuterium by deuterium or neon plasma sheath on plasma-focus discharge
Authors: Kubes P. , Paduch M. , Cikhardt J. , Kortanek J. , Cikhardtova B. , Rezac K. , Klir D. , Kravarik J. , Zielinska E.
Published: December 2014

The present experiments were performed on the PF-1000 plasma focus device at a current of 2 MA with the deuterium injected from the gas-puff placed in the axis of the anode face. The XUV frames showed, in contrast with the interferograms, the fine structure: filaments and spots up to 1 mm diameter. In the deuterium filling, the short filaments are registered mainly in the region of the internal plasmoidal structures and their number correlates with the intensity of neutron production. The longer filamentary structure was recorded close to the anode after the constriction decay. The long curve-like filaments with spots were registered in the big bubble formed after the pinch phase in the head of the umbrella shape of the plasma sheath. Filaments can indicate the filamentary structure of the current in the pinch. Together with the filaments, small compact balls a few mm in diameter were registered by both interferometry and XUV frame pictures. They emerge out of the dense column and their life-time can be greater than hundreds of ns.
Geodesic acoustic mode in anisotropic plasmas using double adiabatic model and gyro-kinetic equation
Authors: Ren Haijun , Cao Jintao
Published: December 2014

Geodesic acoustic mode in anisotropic tokamak plasmas is theoretically analyzed by using double adiabatic model and gyro-kinetic equation. The bi-Maxwellian distribution function for guiding-center ions is assumed to obtain a self-consistent form, yielding pressures satisfying the magnetohydrodynamic (MHD) anisotropic equilibrium condition. The double adiabatic model gives the dispersion relation of geodesic acoustic mode (GAM), which agrees well with the one derived from gyro-kinetic equation. The GAM frequency increases with the ratio of pressures, p⊥/p∥, and the Landau damping rate is dramatically decreased by p⊥/p∥. MHD result shows a low-frequency zonal flow existing for all p⊥/p∥, while according to the kinetic dispersion relation, no low-frequency branch exists for p⊥/p∥≳ 2.
Electrochemically grafted polypyrrole changes photoluminescence of electronic states inside nanocrystalline diamond
Authors: Galář P. , Čermák J. , Malý P. , Kromka A. , Rezek B.
Published: December 2014

Hybrid diamond-organic interfaces are considered attractive for diverse applications ranging from electronics and energy conversion to medicine. Here we use time-resolved and time-integrated photoluminescence spectroscopy in visible spectral range (380–700 nm) to study electronic processes in H-terminated nanocrystalline diamond films (NCD) with 150 nm thin, electrochemically deposited polypyrrole (PPy) layer. We observe changes in dynamics of NCD photoluminescence as well as in its time-integrated spectra after polymer deposition. The effect is reversible. We propose a model where the PPy layer on the NCD surface promotes spatial separation of photo-generated charge carriers both in non-diamond carbon phase and in bulk diamond. By comparing different NCD thicknesses we show that the effect goes as much as 200 nm deep inside the NCD film.
Investigation of the oxidation states of Cu additive in colored borosilicate glasses by electron energy loss spectroscopy
Authors: Yang Guang , Cheng Shaodong , Li Chao , Zhong Jiasong , Ma Chuansheng , Wang Zhao , Xiang Weidong
Published: December 2014

Three optically transparent colorful (red, green, and blue) glasses were synthesized by the sol-gel method. Nano-sized precipitates were found in scanning electron microscopy images. The precipitates were analyzed by transmission electron microscopy (TEM) and high resolution TEM. The measured lattice parameters of these precipitates were found to fit the metallic copper in red glass but deviate from single valenced Cu oxides in green and blue glasses. The chemistry of these nano-sized particles was confirmed by electron energy loss spectroscopy (EELS). By fitting the EELS spectra obtained from the precipitates with the linear combination of reference spectra from Cu reference compounds, the oxidation states of Cu in the precipitates have been derived. First principle calculations suggested that the Cu nano-particles, which are in the similar oxidation states as our measurement, would show green color in the visible light range.
Electronic structure of ruthenium-doped iron chalcogenides
Authors: Winiarski M. J. , Samsel-Czekała M. , Ciechan A.
Published: December 2014

The structural and electronic properties of hypothetical RuxFe1−xSe and RuxFe1−xTe systems have been investigated from first principles within the density functional theory (DFT). Reasonable values of lattice parameters and chalcogen atomic positions in the tetragonal unit cell of iron chalcogenides have been obtained with the use of norm-conserving pseudopotentials. The well known discrepancies between experimental data and DFT-calculated results for structural parameters of iron chalcogenides are related to the semicore atomic states which were frozen in the used here approach. Such an approach yields valid results of the electronic structures of the investigated compounds. The Ru-based chalcogenides exhibit the same topology of the Fermi surface (FS) as that of FeSe, differing only in subtle FS nesting features. Our calculations predict that the ground states of RuSe and RuTe are nonmagnetic, whereas those of the solid solutions RuxFe1−xSe and RuxFe1−xTe become the single- and double-stripe antiferromagnetic, respectively. However, the calculated stabilization energy values are comparable for each system. The phase transitions between these magnetic arrangements may be induced by slight changes of the chalcogen atom positions and the lattice parameters a in the unit cell of iron selenides and tellurides. Since the superconductivity in iron chalcogenides is believed to be mediated by the spin fluctuations in single-stripe magnetic phase, the RuxFe1−xSe and RuxFe1−xTe systems are good candidates for new superconducting iron-based materials.
Pressure-magnetic field induced phase transformation in Ni46Mn41In13 Heusler alloy
Authors: Rama Rao N. V. , Manivel Raja M. , Esakki Muthu S. , Arumugam S. , Pandian S.
Published: December 2014

The effect of hydrostatic pressure and magnetic field on the magnetic properties and phase transformation in Ni46Mn41In13 Heusler alloy was investigated. Pressure (P)-magnetic field (H)-temperature (T) phase diagram has been constructed from experimental results. In the P–T contour of the phase diagram, the slope of the austenite-martensite phase boundary line appears positive (dT/dP > 0), while it appears negative (dT/dH < 0) in the H–T contour. The results revealed that pressure and magnetic field have opposite effect on phase stabilization. The combined effect of pressure and magnetic field on martensitic transition has led to two important findings: (i) pressure dependent shift of austenite start temperature (As) is higher when larger field is applied, and (ii) field dependent shift of As is lowered when a higher pressure is applied. The pressure and magnetic field dependent shift observed in the martensitic transformation has been explained on the basis of thermodynamic calculations. Curie temperature of the phases was found to increase with pressure at a rate of 0.6 K/kbar.
Thermal behaviors of liquid La-based bulk metallic glasses
Authors: Zhang D. W. , Wang X. D. , Lou H. B. , Cao Q. P. , Wang L. W. , Zhang D. X. , Jiang J. Z.
Published: December 2014

Thermal behaviors of liquid La-based bulk metallic glasses have been measured by using the dilatometer with a self-sealed sample cell. It is demonstrated that the strong glass forming liquid not only has the small thermal expansion coefficient but also shows the slow variation rate. Moreover, the strong glass former has relatively dense atomic packing and also small density change in the liquid state. The results suggest that the high glass forming ability of La-based metallic glasses would be closely related to the slow atomic rearrangements in liquid melts.
Dust particles under the influence of crossed electric and magnetic fields in the sheath of an rf discharge
Authors: Puttscher M. , Melzer A.
Published: December 2014

Experimental studies on the interaction of micron-sized dust particles in plasmas with external magnetic fields are presented. The particles are levitated in the sheath region of an rf discharge by gravity and electric field force under the presence of a horizontal magnetic field of up to 50 mT. It is observed that the dust particles are pushed either in the E→×B→- or in the opposite direction depending on magnetic field strength, particle properties, and discharge conditions. This transport behavior is described by a competition between horizontal ambipolar electric field force and ion and neutral drag.
Formation of size controlled silicon nanocrystals in nitrogen free silicon dioxide matrix prepared by plasma enhanced chemical vapor deposition
Authors: Laube J. , Gutsch S. , Hiller D. , Bruns M. , Kübel C. , Weiss C. , Zacharias M.
Published: December 2014

This paper reports the growth of silicon nanocrystals (SiNCs) from SiH4–O2 plasma chemistry. The formation of an oxynitride was avoided by using O2 instead of the widely used N2O as precursor. X-ray photoelectron spectroscopy is used to prove the absence of nitrogen in the layers and determine the film stoichiometry. It is shown that the Si rich film growth is achieved via non-equilibrium deposition that resembles a interphase clusters mixture model. Photoluminescence and Fourier transformed infrared spectroscopy are used to monitor the formation process of the SiNCs, to reveal that the phase separation is completed at lower temperatures as for SiNCs based on oxynitrides. Additionally, transmission electron microscopy proves that the SiNC sizes are well controllable by superlattice configuration, and as a result, the optical emission band of the Si nanocrystal can be tuned over a wide range.
Multi-images deconvolution improves signal-to-noise ratio on gated stimulated emission depletion microscopy
Authors: Castello Marco , Diaspro Alberto , Vicidomini Giuseppe
Published: December 2014

Time-gated detection, namely, only collecting the fluorescence photons after a time-delay from the excitation events, reduces complexity, cost, and illumination intensity of a stimulated emission depletion (STED) microscope. In the gated continuous-wave- (CW-) STED implementation, the spatial resolution improves with increased time-delay, but the signal-to-noise ratio (SNR) reduces. Thus, in sub-optimal conditions, such as a low photon-budget regime, the SNR reduction can cancel-out the expected gain in resolution. Here, we propose a method which does not discard photons, but instead collects all the photons in different time-gates and recombines them through a multi-image deconvolution. Our results, obtained on simulated and experimental data, show that the SNR of the restored image improves relative to the gated image, thereby improving the effective resolution.
Terahertz quantum well photodetectors with reflection-grating couplers
Authors: Zhang R. , Fu Z. L. , Gu L. L. , Guo X. G. , Cao J. C.
Published: December 2014

The design, fabrication, and characterization of terahertz (THz) quantum well photodetectors with one-dimensional reflection-grating coupler are presented. It is found that the reflection gratings could effectively couple the THz waves normally incident to the device. Compared with the 45-degree facet sample, the peak responsivity of this grating-coupled detector is enhanced by over 20%. The effects of the gratings on the photocurrent spectra are also analyzed.
Acoustic superfocusing by solid phononic crystals
Authors: Zhou Xiaoming , Assouar M. Badreddine , Oudich Mourad
Published: December 2014

We propose a solid phononic crystal lens capable of acoustic superfocusing beyond the diffraction limit. The unit cell of the crystal is formed by four rigid cylinders in a hosting material with a cavity arranged in the center. Theoretical studies reveal that the solid lens produces both negative refraction to focus propagating waves and surface states to amplify evanescent waves. Numerical analyses of the superfocusing effect of the considered solid phononic lens are presented with a separated source excitation to the lens. In this case, acoustic superfocusing beyond the diffraction limit is evidenced. Compared to the fluid phononic lenses, the solid lens is more suitable for ultrasonic imaging applications.
Moving on? Neoliberal continuities through crisis: the case of the Chilean salmon industry and the ISA virus
Authors: Bustos Beatriz
Published: December 2014

Recent development literature on Latin America has discussed whether a ‘postneoliberal’ era has arrived. In this paper I argue that determining the arrival of a postneoliberal moment requires an examination of how capital crises are resolved by the state and the market to see whether institutions and the policy responses created by their interaction constitute a new approach to capital accumulation. After presenting geographical debates on crisis formation, I focus on the Infectious Salmon Anemia crisis that affected the Chilean salmon industry in 2008, and which raised questions about Chile's neoliberal success and global integration. Using interviews, press reports, and public data, I find that the policy responses that were implemented—namely, a new regulatory framework, increased state oversight, and geographical relocation—deepened Chile's trust in a neoliberal economy. This finding suggests that, at least in terms of environmental governance, we have not arrived at a postneoliberal moment.