bluuebunny/crossref_metadata_2025 huggingface dataset:
Highly selective and sensitive detection of glutathione using mesoporous silica nanoparticles capped with disulfide-containing oligo(ethylene glycol) chains
Authors: El Sayed Sameh , Giménez Cristina , Aznar Elena , Martínez-Máñez Ramón , Sancenón Félix , Licchelli Maurizio
Published: November 2014

Mesoporous silica nanoparticles loaded with safranin O and capped with disulfide-containing oligo(ethylene glycol) chains were used for the selective and sensitive fluorimetric detection of GSH.
Aryl-bis-(scorpiand)-aza receptors differentiate between nucleotide monophosphates by a combination of aromatic, hydrogen bond and electrostatic interactions
Authors: González-García Jorge , Tomić Sanja , Lopera Alberto , Guijarro Lluís , Piantanida Ivo , García-España Enrique
Published: November 2014

Bis-scorpiands bind nucleotides in water with 10–100 μM affinity, with selectivity: at pH 7 pyridine-scorpiand toward CMP; at pH 5 phenanthroline-scorpiand toward AMP.
Pd-catalyzed Heck-conjoined amidation and concomitant chemoselective Michael-addition: an efficient tandem approach to highly functionalized tetrahydroquinazolines from o-haloanilines
Authors: Saunthwal Rakesh K. , Patel Monika , Danodia Abhinandan K. , Verma Akhilesh K.
Published: November 2014

Efficient palladium-catalyzed tandem approach for the synthesis of highly functionalized tetrahydroquinazolines fromo-haloanilines with acrylates and isothiocyanates/isocyanatesviaHeck-conjoined amidation/thioamidation and concomitant chemoselective Michael-addition is described.
Modified strontium titanates: from defect chemistry to SOFC anodes
Authors: Verbraeken M. C. , Ramos T. , Agersted K. , Ma Q. , Savaniu C. D. , Sudireddy B. R. , Irvine J. T. S. , Holtappels P. , Tietz F.
Published: November 2014

A review describing how compositional design of modified strontium titanates can lead to conductive, redox stable SOFC anodes.
Highly stable and covalently functionalized magnetic nanoparticles by polyethyleneimine for Cr(vi) adsorption in aqueous solution
Authors: Chen Bo , Zhao Xuesong , Liu Yang , Xu Bugang , Pan Xuejun
Published: November 2014

Covalently functionalized magnetic nanocomposite by polyethyleneimine (PEI) acted as superior adsorbent for removal of Cr(vi) form water.
Selective anti-cancer effects of palm phytonutrients on human breast cancer cells
Authors: Loganathan Radhika , Radhakrishnan Ammu K. , Selvaduray Kanga Rani , Nesaretnam Kalanithi
Published: November 2014

Palm TRF exhibited higher potential to induce death by apoptosis and cleavage of the PARP enzyme as well as suppress expression of NF-κB induced by exposure to TNF-α in human breast cancer cells compared to carotenoids, squalene and co-enzyme Q10.
Alkylation desulfurization of the C9 fraction over Amberlyst 36 resin
Authors: Xu Weiwei , Li Yonghong
Published: November 2014

Conversions of thiophenic compounds close to 99% with increased octane number of the C9 fraction were obtained after alkylation desulfurization over Amberlyst 36 resin, suggesting a new way to reduce the sulfur content in the C9 fraction.
Oxidative C–S bond cleavage reaction of DMSO for C–N and C–C bond formation: new Mannich-type reaction for β-amino ketones
Authors: Sun Kai , Lv Yunhe , Zhu Zhonghong , Zhang Liping , Wu Hankui , Liu Lin , Jiang Yongqing , Xiao Beibei , Wang Xin
Published: November 2014

A novel oxidative C–S bond cleavage reaction of DMSO for N-methylation and subsequent C–C bond formation is described.
Restructuring and Hydrogen Evolution on Pt Nanoparticle
Authors: Wei Guang-Feng , Liu Zhi-Pan
Published: November 2014

Dynamic catalyst structuring and the hydrogen evolution activity enhancement at nanoscale, as predicted by a first principles global optimization method.
Core–shell structured Ce2S3@ZnO and its potential as a pigment
Authors: Mao Wen-Xin , Zhang Wei , Chi Zi-Xiang , Lu Rong-Wen , Cao An-Min , Wan Li-Jun
Published: November 2014

A uniform nanoshell of ZnO can effectively eliminate H2S and enhance the thermostability of Ce2S3.
Yogurt: a novel precursor for heavily nitrogen doped supercapacitor carbon
Authors: Wahid Malik , Parte Golu , Phase Deodatta , Ogale Satishchandra
Published: November 2014

The transformation of the globular structures of yogurt into a porous high-capacitive carbon material, displaying the perfect double layer capacitive behavior.
Poly(ester-ether)s: III. assessment of cell behaviour on nanofibrous scaffolds of PCL, PLLA and PDX blended with amorphous PMeDX
Authors: Goonoo N. , Bhaw-Luximon A. , Rodriguez I. A. , Wesner D. , Schönherr H. , Bowlin G. L. , Jhurry D.
Published: November 2014

SEM images of HDF cells on scaffolds: (a) PCL/PMeDX: 93/7-good adhesion and proliferation, (b) PDX/PMeDX: 98/2-good adhesion, proliferation & infiltration and (c) PLLA/PMeDX: 85/15-good proliferation and infiltration.
Direct growth of graphene nanopatches on graphene sheets for highly conductive thin film applications
Authors: Song Wooseok , Kim Ki Woong , Chang Sung-Jin , Park Tae Jung , Kim Sung Ho , Jung Min Wook , Lee Geonhee , Myung Sung , Lim Jongsun , Lee Sun Suk , An Ki-Seok
Published: November 2014

Graphene nanopatches on graphene sheets were synthesized by Ni nanoparticle assembly and subsequent CVD growth to enhance their electrical conductivity.
Size tunable elemental copper nanoparticles: extracellular synthesis by thermoanaerobic bacteria and capping molecules
Authors: Jang Gyoung Gug , Jacobs Christopher B. , Gresback Ryan G. , Ivanov Ilia N. , Meyer, III Harry M. , Kidder Michelle , Joshi Pooran C. , Jellison Gerald E. , Phelps Tommy J. , Graham David E. , Moon Ji-Won
Published: November 2014

Elemental Cu nanoparticles in aqueous solution were synthesized by a biological process using anaerobic metal-reducing bacteria and chelator and capping molecules.
Long-wavelength shift and enhanced room temperature photoluminescence efficiency in GaAsSb/InGaAs/GaAs-based heterostructures emitting in the spectral range of 1.0–1.2 μm due to increased charge carrier's localization
Authors: Kryzhkov D. I. , Yablonsky A. N. , Morozov S. V. , Aleshkin V. Ya. , Zvonkov B. N. , Vikhrova O. V. , Krasilnik Z. F.
Published: November 2014

In this work, a study of the photoluminescence (PL) temperature dependence in quantum well GaAs/GaAsSb and double quantum well InGaAs/GaAsSb/GaAs heterostructures grown by metalorganic chemical vapor deposition with different parameters of GaAsSb and InGaAs layers has been performed. It has been demonstrated that in double quantum well InGaAs/GaAsSb/GaAs heterostructures, a significant shift of the PL peak to a longer-wavelength region (up to 1.2 μm) and a considerable reduction in the PL thermal quenching in comparison with GaAs/GaAsSb structures can be obtained due to better localization of charge carriers in the double quantum well. For InGaAs/GaAsSb/GaAs heterostructures, an additional channel of radiative recombination with participation of the excited energy states in the quantum well, competing with the main ground-state radiative transition, has been revealed.
The effects of methyl internal rotation and 14N quadrupole coupling in the microwave spectra of two conformers of N,N-diethylacetamide
Authors: Kannengießer Raphaela , Klahm Sebastian , Vinh Lam Nguyen Ha , Lüchow Arne , Stahl Wolfgang
Published: November 2014

The gas phase structures and internal dynamics of N,N-diethylacetamide were determined with very high accuracy using a combination of molecular beam Fourier-transform microwave spectroscopy and quantum chemical calculations at high levels. Conformational studies yielded five stable conformers with C1 symmetry. The two most energetically favorable conformers, conformer I and II, could be found in the experimental spectrum. For both conformers, quadrupole hyperfine splittings of the 14N nucleus and torsional fine splittings due to the internal rotation of the acetyl methyl group occurred in the same order of magnitude and were fully assigned. The rotational constants, centrifugal distortion constants as well as the quadrupole coupling constants of the 14N nucleus were determined and fitted to experimental accuracy. The V3 potentials were found to be 517.04(13) cm−1 and 619.48(91) cm−1 for conformer I and II, respectively, and compared to the V3 potentials found in other acetamides. Highly accurate CCSD(T) and DMC calculations were carried out for calculating the barriers to internal rotation in comparison with the experimentally deduced V3 values.
The local phase transitions of the solvent in the neighborhood of a solvophobic polymer at high pressures
Authors: Budkov Yu. A. , Vyalov I. I. , Kolesnikov A. L. , Georgi N. , Chuev G. N. , Kiselev M. G.
Published: November 2014

We investigate local phase transitions of the solvent in the neighborhood of a solvophobic polymer chain which is induced by a change of the polymer-solvent repulsion and the solvent pressure in the bulk solution. We describe the polymer in solution by the Edwards model, where the conditional partition function of the polymer chain at a fixed radius of gyration is described by a mean-field theory. The contributions of the polymer-solvent and the solvent-solvent interactions to the total free energy are described within the mean-field approximation. We obtain the total free energy of the solution as a function of the radius of gyration and the average solvent number density within the gyration volume. The resulting system of coupled equations is solved varying the polymer-solvent repulsion strength at high solvent pressure in the bulk. We show that the coil-globule (globule-coil) transition occurs accompanied by a local solvent evaporation (condensation) within the gyration volume.
Bulk sensitive hard x-ray photoemission electron microscopy
Authors: Patt M. , Wiemann C. , Weber N. , Escher M. , Gloskovskii A. , Drube W. , Merkel M. , Schneider C. M.
Published: November 2014

Hard x-ray photoelectron spectroscopy (HAXPES) has now matured into a well-established technique as a bulk sensitive probe of the electronic structure due to the larger escape depth of the highly energetic electrons. In order to enable HAXPES studies with high lateral resolution, we have set up a dedicated energy-filtered hard x-ray photoemission electron microscope (HAXPEEM) working with electron kinetic energies up to 10 keV. It is based on the NanoESCA design and also preserves the performance of the instrument in the low and medium energy range. In this way, spectromicroscopy can be performed from threshold to hard x-ray photoemission. The high potential of the HAXPEEM approach for the investigation of buried layers and structures has been shown already on a layered and structured SrTiO3 sample. Here, we present results of experiments with test structures to elaborate the imaging and spectroscopic performance of the instrument and show the capabilities of the method to image bulk properties. Additionally, we introduce a method to determine the effective attenuation length of photoelectrons in a direct photoemission experiment.
Note: A short-pulse high-intensity molecular beam valve based on a piezoelectric stack actuator
Authors: Abeysekera Chamara , Joalland Baptiste , Shi Yuanyuan , Kamasah Alexander , Oldham James M. , Suits Arthur G.
Published: November 2014

Solenoid and piezoelectric disk valves, which are widely used to generate molecular beam pulses, still suffer from significant restrictions, such as pulse durations typically >50 μs, low repetition rates, and limited gas flows and operational times. Much of this arises owing to the limited forces these actuators can achieve. To overcome these limitations, we have developed a new pulsed valve based on a high-force piezoelectric stack actuator. We show here that operation with pulse durations as low as 20 μs and repetition rates up to 100 Hz can be easily achieved by operating the valve in conjunction with a commercial fast high-voltage switch. We outline our design and demonstrate its performance with molecular beam characterization via velocity map ion imaging.
Image plate characterization and absolute calibration to low kilo-electron-volt electrons
Authors: Busold S. , Philipp K. , Otten A. , Roth M.
Published: November 2014

We report on the characterization of an image plate and its absolute calibration to electrons in the low keV energy range (1–30 keV). In our case, an Agfa MD4.0 without protection layer was used in combination with a Fuji FLA7000 scanner. The calibration data are compared to other published data and a consistent picture of the sensitivity of image plates to electrons is obtained, which suggests a validity of the obtained calibration up to 100 keV.
Compact and high-efficiency device for Raman scattering measurement using optical fibers
Authors: Mitsui Tadashi
Published: November 2014

We describe the design and development of a high-efficiency optical measurement device for operation within the small bore of a high-power magnet at low temperature. For the high-efficiency measurement of light emitted from this small region, we designed a compact confocal optics with lens focusing and tilting systems, and used a piezodriven translation stage that allows micron-scale focus control of the sample position. We designed a measurement device that uses 10 m-long optical fibers in order to avoid the influence of mechanical vibration and magnetic field leakage of high-power magnets, and we also describe a technique for minimizing the fluorescence signal of optical fibers. The operation of the device was confirmed by Raman scattering measurements of monolayer graphene on quartz glass with a high signal-to-noise ratio.
Transport induced by ion cyclotron range of frequencies waves
Authors: Zhang Debing , Xu Yingfeng , Wang Shaojie
Published: November 2014

The Vlasov equation, which includes the effect of the ion cyclotron range of frequencies (ICRF) waves, can be written as the Fokker-Planck equation which describes the quasilinear transport in phase space by using the Lie-transform method. The radial transport fluxes of particle, energy and parallel momentum driven by ICRF waves in the slab geometry have been derived. The results show that the ICRF-induced radial redistributions of particle, energy and parallel momentum are driven by the inhomogeneity in energy of the equilibrium distribution function, and related to the correlation between the excursion in the real space and the excursion in energy. For the case with strong asymmetry of ky spectrum, the ICRF-induced radial transport driven by the energy inhomogeneity dominates the ICRF-induced radial transport driven by the spatial inhomogeneity.
Influence of O2 on the dielectric properties of CO2 at the elevated temperatures
Authors: Rong Mingzhe , Sun Hao , Yang Fei , Wu Yi , Chen Zhexin , Wang Xiaohua , Wu Mingliang
Published: November 2014

SF6 gas is widely used in the high voltage circuit breakers but considering its high global warming potential other substitutes are being sought. Among them CO2 was investigated and even has been used in some practical products. However, at room temperature, the dielectric properties of CO2 are relatively lower than SF6 and air. The goal of this work is to investigate a CO2-based gas to improve the performance of the pure CO2. In this paper, the dielectric properties of hot CO2/O2 mixtures related to the dielectric recovery phase of the circuit breaker were investigated in the temperature range from 300 K to 4000 K and in the pressure range from 0.01 MPa to 1.0 MPa. The species compositions of hot CO2/O2 were obtained based on Gibbs free energy minimization under the assumptions of local thermodynamic equilibrium and local chemical equilibrium. The reduced critical electric field strength of CO2/O2 was determined by balancing electron generation and loss. These were calculated using the electron energy distribution function by solving the Boltzmann transport equation. The validity of the calculation method and the cross sections data was confirmed by comparing the measurements and calculations of the electron swarm data in previous work. The results indicate that in pure CO2 the critical electric field strength is higher only in higher temperature range. By adding the O2 into the CO2, the critical electric field strength at lower temperature is effectively enhanced. CO2/O2 mixtures have a much better dielectric strength than both the pure CO2 and air and thus have the potential to improve the CO2-based gas circuit breakers. Similar conclusions can also be found in others’ work, which further confirm the validity of these results.
Orbit-based analysis of resonant excitations of Alfvén waves in tokamaks
Authors: Bierwage Andreas , Shinohara Kouji
Published: November 2014

The exponential growth phase of fast-ion-driven Alfvénic instabilities is simulated and the resonant wave-particle interactions are analyzed numerically. The simulations are carried out in realistic magnetic geometry and with a realistic particle distribution for a JT-60U plasma driven by negative-ion-based neutral beams. In order to deal with the large magnetic drifts of the fast ions, two new mapping methods are developed and applied. The first mapping yields the radii and pitch angles at the points, where the unperturbed orbit of a particle intersects the mid-plane. These canonical coordinates allow to express analysis results (e.g., drive profiles and resonance widths) in a form that is easy to understand and directly comparable to the radial mode structure. The second mapping yields the structure of the wave field along the particle trajectory. This allows us to unify resonance conditions for trapped and passing particles, determine which harmonics are driven, and which orders of the resonance are involved. This orbit-based resonance analysis (ORA) method is applied to fast-ion-driven instabilities with toroidal mode numbers n = 1-3. After determining the order and width of each resonance, the kinetic compression of resonant particles and the effect of linear resonance overlap are examined. On the basis of the ORA results, implications for the fully nonlinear regime, for the long-time evolution of the system in the presence of a fast ion source, and for the interpretation of experimental observations are discussed.
Spintronics with graphene-hexagonal boron nitride van der Waals heterostructures
Authors: Kamalakar M. Venkata , Dankert André , Bergsten Johan , Ive Tommy , Dash Saroj P.
Published: November 2014

Hexagonal boron nitride (h-BN) is a large bandgap insulating isomorph of graphene, ideal for atomically thin tunnel barrier applications. In this letter, we demonstrate large area chemical vapor deposited (CVD) h-BN as a promising spin tunnel barrier in graphene spin transport devices. In such structures, the ferromagnetic tunnel contacts with h-BN barrier are found to show robust tunneling characteristics over a large scale with resistances in the favorable range for efficient spin injection into graphene. The non-local spin transport and precession experiments reveal spin lifetime ≈500 ps and spin diffusion length ≈1.6 μm in graphene with tunnel spin polarization ≈11% at 100 K. The electrical and spin transport measurements at different injection bias current and gate voltages confirm tunnel spin injection through h-BN barrier. These results open up possibilities for implementation of large area CVD h-BN in spintronic technologies.
Nonreciprocal photonic crystal add-drop filter
Authors: Tao Keyu , Xiao Jun-Jun , Yin Xiaobo
Published: November 2014

We present a versatile add-drop integrated photonic filter (ADF) consisting of nonreciprocal waveguides in which the propagation of light is restricted in one predetermined direction. With the bus and add/drop waveguides symmetrically coupled through a cavity, the four-port device allows each individual port to add and/or drop a signal of the same frequency. The scheme is general and we demonstrate the nonreciprocal ADF with magneto-optical photonic crystals. The filter is immune to waveguide defects, allowing straightforward implementation of multi-channel ADFs by cascading the four-port designs. The results should find applications in wavelength-division multiplexing and related integrated photonic techniques.
Slowing of femtosecond laser-generated nanoparticles in a background gas
Authors: Rouleau C. M. , Puretzky A. A. , Geohegan D. B.
Published: November 2014

The slowing of Pt nanoparticles in argon background gas was characterized by Rayleigh scattering imaging using a plume of nanoparticles generated by femtosecond laser through thin film ablation of 20 nm-thick Pt films. The ablation was performed at threshold laser energy fluences for complete film removal to provide a well-defined plume consisting almost entirely of nanoparticles traveling with a narrow velocity distribution, providing a unique system to unambiguously characterize the slowing of nanoparticles during interaction with background gases. Nanoparticles of ∼200 nm diameter were found to decelerate in background Ar gas with pressures less than 50 Torr in good agreement with a linear drag model in the Epstein regime. Based on this model, the stopping distance of small nanoparticles in the plume was predicted and tested by particle collection in an off-axis geometry, and size distribution analysis by transmission electron microscopy. These results permit a basis to interpret nanoparticle propagation through background gases in laser ablation plumes that contain mixed components.
Impact of incorporating sodium into polycrystalline p-type Cu2O for heterojunction solar cell applications
Authors: Minami Tadatsugu , Nishi Yuki , Miyata Toshihiro
Published: November 2014

The resistivity was controlled in the range of 103 to 10−2 Ω cm in polycrystalline p-type Cu2O sheets (incorporating sodium (Na)), which are suitable for Cu2O-based heterojunction solar cell applications. The Na-doped Cu2O sheets exhibited a hole concentration that ranged from 1013 to 1019 cm−3. In particular, a hole concentration of 1013–1016 cm−3 was obtained while maintaining a high Hall mobility above 100 cm2/V s, and, in addition, a degenerated semiconductor exhibiting metallic conduction was realized with a hole concentration above about 1 × 1019 cm−3. The mechanism associated with the Na doping can be explained by a copper vacancy produced due to charge compensation effects that result when a Na atom is incorporated at an interstitial site in the Cu2O lattice. For solar cell applications, the use of the Cu2O:Na sheet in a heterojunction solar cell successfully improved the obtained efficiency over that found in heterojunction solar cells fabricated using an undoped Cu2O sheet.
Acoustoelastic effects of Stoneley waves in a borehole surrounded by a transversely isotropic elastic solid
Authors: Liu Jinxia , Cui Zhiwen , Cao Zhengliang , Wang Kexie
Published: November 2014

Stoneley wave in a fluid-filled pressurized borehole surrounded by a transversely isotropic elastic solid with nine independent third-order elastic constants in presence of biaxial stresses are studied. A simplified acoustoelastic formulation of Stoneley wave is presented for the parallelism of the borehole axis and the formation axis of symmetry. Sensitivity coefficients and velocity dispersions for Stoneley wave due to the presence of stresses are numerically investigated, respectively. The acoustoelastic formulation explicitly shows that the velocity dispersions of Stoneley wave depend on seven independent third-order elastic constants in presence of biaxial stresses and on six independent third-order elastic constants in the presence of borehole pressurization alone. Numerical results of both sensitivity coefficients and velocity dispersions of Stoneley wave show that at low frequency the velocity change of Stoneley wave is sensitive to c111 and c112. Stoneley wave velocity at low frequencies can be simplified by 3 independent third order elastic constants (c111, c112 and c123) instead of nine constants. In presence of biaxial stresses, at low frequencies the speed of the Stoneley wave is similar to White’s formula.
Fabrication of anti-adhesion surfaces on aluminium substrates of rubber plastic moulds using electrolysis plasma treatment
Authors: Meng Jianbing , Dong Xiaojuan , Wei Xiuting , Yin Zhanmin
Published: November 2014

An anti-adhesion surface with a water contact angle of 167° was fabricated on aluminium samples of rubber plastic moulds by electrolysis plasma treatment using mixed electrolytes of C6H5O7(NH4)3 and Na2SO4, followed by fluorination. To optimise the fabrication conditions, several important processing parameters such as the discharge voltage, discharge time, concentrations of supporting electrolyte and stearic acid ethanol solution were examined systematically. Using scanning electron microscopy (SEM) to analyse surfaces morphology, micrometer scale pits, and protrusions were found on the surface, with numerous nanometer mastoids contained in the protrusions. These binary micro/nano-scale structures, which are similar to the micro-structures of soil-burrowing animals, play a critical role in achieving low adhesion properties. Otherwise, the anti-adhesion behaviours of the resulting samples were analysed by the atomic force microscope (AFM), Fourier-transform infrared spectrophotometer (FTIR), electrons probe micro-analyzer (EPMA), optical contact angle meter, digital Vickers microhardness (Hv) tester, and electronic universal testing. The results show that the electrolysis plasma treatment does not require complex processing parameters, using a simple device, and is an environment-friendly and effective method. Under the optimised conditions, the contact angle (CA) for the modified anti-adhesion surface is up to 167°, the sliding angle (SA) is less than 2°, roughness of the sample surface is only 0.409μm. Moreover, the adhesion force and Hv are 0. 9KN and 385, respectively.
Fabrication of 5-20 nm thick β-W films
Authors: Narasimham Avyaya J. , Medikonda Manasa , Matsubayashi Akitomo , Khare Prasanna , Chong Hyuncher , Matyi Richard J. , Diebold Alain , LaBella Vincent P.
Published: November 2014

A technique to fabricate 5 to 20 nm thick sputter deposited β W films on SiO2 and Si substrates is presented. This is achieved by growing tungsten on a 5 nm SiO2 layer or in an oxygen controlled environment by flowing 2 sccm of O2 during deposition. Resistivity, X-ray photoelectron spectroscopy, X-ray diffraction and reflectivity studies were performed to determine the phase and thickness of tungsten films. These results demonstrate a technique to grow this film on bare Si or a SiO2 substrate, which can enable growth on the bottom of a write unit in a non-volatile spin logic device.
On square-wave-driven stochastic resonance for energy harvesting in a bistable system
Authors: Su Dongxu , Zheng Rencheng , Nakano Kimihiko , Cartmell Matthew P
Published: November 2014

Stochastic resonance is a physical phenomenon through which the throughput of energy within an oscillator excited by a stochastic source can be boosted by adding a small modulating excitation. This study investigates the feasibility of implementing square-wave-driven stochastic resonance to enhance energy harvesting. The motivating hypothesis was that such stochastic resonance can be efficiently realized in a bistable mechanism. However, the condition for the occurrence of stochastic resonance is conventionally defined by the Kramers rate. This definition is inadequate because of the necessity and difficulty in estimating white noise density. A bistable mechanism has been designed using an explicit analytical model which implies a new approach for achieving stochastic resonance in the paper. Experimental tests confirm that the addition of a small-scale force to the bistable system excited by a random signal apparently leads to a corresponding amplification of the response that we now term square-wave-driven stochastic resonance. The study therefore indicates that this approach may be a promising way to improve the performance of an energy harvester under certain forms of random excitation.
Pressure and tension effects on mechanical properties of ZrAl2
Authors: Zhang Pinliang , Meng Fanchen , Gong Zizheng , Ji Guangfu , Yang Jinke , Tang Xiuzhang
Published: November 2014

Structural, elastic, thermodynamic of ZrAl2 under pressure, ideal strength and deformation mode under tension are investigated by the first-principles method. The calculated structural parameters at zero pressure are in consistent with experiments. Under pressure, elastic constants and their pressure dependence are obtained using the static finite strain technique. ZrAl2 exhibits lower elastic anisotropy. The linear thermal expansion coefficient shows greater effects of temperature at lower pressure. The ideal tensile have been investigated by stress–strain calculations. Finally, the microscopic mechanism that determines the structural stability is studied using the results of electronic structure calculations. We propose that the weakening of Zr-Zr leads to the significant change of stress–strain curve at strain ∼0.27, and the breaking of Zr2-Zr3 leads to the structural instability of ZrAl2 under large tensile strains.
Genotypic and morphological variation between Galaxiella nigrostriata (Galaxiidae) populations: implications for conservation
Authors: Galeotti David M. , Castalanelli Mark A. , Groth David M. , McCullough Clint , Lund Mark
Published: November 2014

Galaxiella nigrostriata is a freshwater fish that is endemic to the seasonally dry coastal wetlands of south-west Western Australia and considered by the International Union for Conservation of Nature (IUCN) as lower risk–near threatened. This small fish (maximum total length<50mm) aestivates in the sediment over the long, dry Mediterranean summer and its dispersal is limited by lack of habitat connectivity. The objective of this study was to identify the historical and contemporary genetic connectivity between populations of G. nigrostriata and to assess morphological variation between these populations. Results showed that all populations were genetically divergent and no mtDNA haplotypes were shared between populations. In contrast, morphological differentiation between individual populations was weak; however, pooling populations into two broad regions (Swan coastal plain and southern coast) resulted in clear morphological differentiation between these two groups. Based on these results, we postulate G. nigrostriata distribution last expanded in the early Pleistocene ~5.1 million years ago and have since been restricted to remnant wetlands in the immediate area. Galaxiella nigrostriata populations at the northern end of their range are small and are the most vulnerable to extinction. Conservation efforts are therefore required to ensure the survival of these genetically and morphologically distinctive Swan coastal plain populations.
Composition and health of fish in refugia habitat of ephemeral tributaries to the lower Zambezi in southern Africa
Authors: Strauch Ayron M. , Kapust Alana R. , Jost Christine C.
Published: November 2014

The ecology of dryland rivers is under-studied in Africa. During seasonal droughts, these rivers cease flowing resulting in disconnected pools that restrict the movement of aquatic species. Few studies have focussed on the conditions of these refugia or their effect on fish. We investigated the influence of pool size and water quality on the abundance and composition of fish, including body condition (BC) and a quantitative heath assessment index (HAI) of individual species in tributaries of the lower Zambezi during the dry season. Although no single species was found among all sites, species in either or both the Cichlidae or Cyprinidae families were recovered in 12 of 15 locations. Fish biomass and richness were positively correlated with refugia size. As water quality declined, Cichlidae BC declined while Cyprinidae BC improved. By contrast, both Cichlidae HAI and Cyprinidae HAI were positively related (declined) to increased dissolved oxygen while negatively related to nutrients. We conclude that refugia conditions affect fish communities but the direction of effect can be species dependent. Increasing our understanding of the effects of land-use and water-use on habitat quality and their consequences for freshwater ecosystems in general should be an important goal towards improving rural livelihoods.
Stable reference genes in granulosa cells of bovine dominant follicles during follicular growth, FSH stimulation and maternal aging
Authors: Khan Muhammad Irfan-ur-Rehman , Dias Fernanda Caminha Faustino , Dufort Isabelle , Misra Vikram , Sirard Marc-Andre , Singh Jaswant
Published: November 2014

The aim of the present study was to determine a set of reference genes in granulosa cells of dominant follicles that are suitable for relative gene expression analyses during maternal and follicular aging. Granulosa cells of growing and preovulatory dominant follicles were collected from aged and young cows (maternal aging study) and from FSH-stimulated follicles developing under different durations of FSH treatment (follicular aging study). The mRNA levels of the two commonly used reference genes (GAPDH, ACTB) and four novel genes (UBE2D2, EIF2B2, SF3A1, RNF20) were analysed using cycle threshold values. Results revealed that mRNA levels of GAPDH, ACTB, EIF2B2, RNF20, SF3A1 and UBE2D2 were similar (P > 0.05) between dominant follicle type, age and among follicles obtained after FSH-stimulation, but differed (P = 0.005) due to mRNA processing (i.e. with versus without amplification). The stability of reference genes was analysed using GeNorm, DeltaCT and NormFinder programs and comprehensive ranking order was determined using RefFinder. The mRNA levels of GAPDH and ACTB were less stable than those of UBE2D2 and EIF2B2. The geometric mean of multiple genes (UBE2D2, EIF2B2, GAPDH and SF3A1) is a more appropriate reference control than the use of a single reference gene to compare relative gene expression among dominant and FSH-stimulated follicles during maternal and/or follicular aging studies.
Enzymatic turnover of macromolecules generates long-lasting protein–water-coupled motions beyond reaction steady state
Authors: Dielmann-Gessner Jessica , Grossman Moran , Conti Nibali Valeria , Born Benjamin , Solomonov Inna , Fields Gregg B. , Havenith Martina , Sagi Irit
Published: November 2014

Significance

The solvent in biological reactions plays an active role in protein function; however, correlating solvation dynamics with specific biological scenarios remains a scientific challenge. Here, we followed time-dependent changes in solvation dynamics using terahertz absorption spectroscopy during proteolysis of collagen substrates by a metalloproteinase. Unexpectedly, we revealed that solvation dynamics do not follow the traditional enzymatic steady-state kinetic theory but generate long-lasting protein–water-coupled motions that last longer than a single catalytic cycle and are substrate-specific. These prolonged solvation dynamics contribute to the net enzyme reactivity impacting substrate binding, positional catalysis, and product release.
Invariance property of wave scattering through disordered media
Authors: Pierrat Romain , Ambichl Philipp , Gigan Sylvain , Haber Alexander , Carminati Rémi , Rotter Stefan
Published: November 2014

Significance

The diffusion of particles and waves through disordered media encompasses a large variety of phenomena, from the motion of insects to the scattering of electrons or light in complex environments. One of the core features of diffusive transport is that the mean length of trajectories traversing a system depends only on the size of the system and of its boundary, which are both independent of the microscopic structure of the underlying medium. Here we show, based on insights from wave-scattering theory, that this fundamental invariance property can be significantly extended beyond the diffusive random walk picture. Our result not only provides an interesting link between all the diverse fields in which wave scattering plays a role but also holds promise for a number of practical applications.
Dissecting the clonal origins of childhood acute lymphoblastic leukemia by single-cell genomics
Authors: Gawad Charles , Koh Winston , Quake Stephen R.
Published: November 2014

Significance

A better understanding of intratumor heterogeneity is required to more fully dissect the events which mediate cancer formation and treatment resistance. We used a novel experimental and computational single-cell sequencing approach to directly measure the clonal structures of childhood ALL samples at diagnosis. This approach enabled us to determine the mutation segregation patterns within a single sample and to reconstruct the tumor’s clonal structures with rigorously validated quantitative analysis. We then identified features of each leukemia sample that were shared across patients, including multiple dominant clonal populations at varied stages in differentiation arrest, clone-specific punctuated cytosine mutagenesis, and the late acquisition of proliferative oncogenic point mutations. Together, these findings provide a high-resolution view of the development of childhood ALL.
Salvation in Plato and St. Paul: An Essay in Normative Ethics
Authors: Nakhnikian George
Published: November 2014

What is a good man, and how does he become good? My aim in this paper is to unravel and to assess Plato's and St. Paul's very different answers to these questions. The pivotal texts are the Republic and Paul's Epistles.

A good man, according to Plato, is a man who is dikaios (righteous, just), temperate, wise, and courageous. A just man is one each one of the three parts (elements, components) of whose soul is doing its own [work, ergon]. We must pause a moment at the crucial passage in 441 DE. Cornford's translation of it is somewhat ambiguous. “ ... each one of us likewise will be a just person, fulfilling his proper function, only if the several parts of our nature fulfil theirs.” According to this rendition Plato may be construed to be saying that a human being is doing his own work as a just person only if each part of his inner nature (=soul) is doing its own work.
Can a Moral Man Raise the Question, “Should I Be Moral?”
Authors: Snare Frank
Published: November 2014

Let it be allowed, though virtue or moral rectitude does indeed consist in affection to and pursuit of what is right and good, as such; yet, that when we sit down in a cool hour, we can neither justify to ourselves this or any other pursuit, till we are convinced that it will be for our happiness, or at least not contrary to it.

—Butler, Sermon XI

There are a number of different grounds on which philosophers have argued that the question “Should I be moral?” is unintelligible or at least somewhat odd. Some evidently are unable to understand ‘should’ in any other way than ‘morally ought’, with the consequence that the question can admit of no answer but the affirmative. Others, influenced by the later Wittgenstein, hold that, although ‘should ’-questions have a role within the moral language game, the ‘should’ in the question above has no real function, it is like a ‘machine idling,’ and we can attribute no real sense to it. Now I consider neither of these arguments to be successful or even very plausible, but I do wish to consider a further argument which is logically independent of the above and which appears, initially at least, to be quite plausible.
Narrative Explanation Revisited
Authors: Ruse Michael
Published: November 2014

T. A. Gouge has argued that certain explanations in evolutionary biology should be understood as conforming to the so-called ‘narrative’ model of explanation, where the chief distinguishing feature between this model and the well-known ‘covering-law’ model is that this narrative model, unlike the covering-law model, makes no appeal at all to laws. In support of his case Goudge offered an example of an evolutionary explanation which, he claimed, comes closer to the narrative model than the covering-law model. In a recent paper in this Journal I offered a critique of Goudge's model of narrative explanation, and I suggested that there were good reasons for understanding Goudge's example of an evolutionary explanation as making some kind of appeal to laws (and thus in vital respects conforming to the covering-law model).
Nietzsche, Skepticism, and Eternal Recurrence
Authors: Kain Philip J.
Published: November 2014

Some Nietzsche scholars, like Wilcox and Kaufmann, think that for Nietzsche there are truths and that knowledge of them is possible. I do not think that this reading is correct. Other scholars, like Danto and Cameron, think that Nietzsche rejects the possibility of truth. In my opinion they are correct, but they also think that this rejection gives rise to serious difficulties in Nietzsche's thought. I think that Nietzsche was aware of these difficulties, consciously sought to get around them, and that his most bizarre doctrines, if understood correctly, succeed in doing so.
An Epistemic Criterion of the Mental
Authors: Levison Arnold B.
Published: November 2014

‘When we see, hear, smell, taste, feel, meditate, or will anything, we know that we do so. … Consciousness … is inseparable from thinking, and essential to it. …’

John Locke,EssayConcerning HumanUnderstanding(II, 27)

‘Psycho-analysis … cannot accept the identity of the conscious and the mental. It defines what is mental as processes such as feeling, thinking and … willing. … ’

Sigmund Freud,Introductory Lectures on Psycho-analysis(Lecture 1 ).

In this paper I shall provide a novel version of a traditional epistemic criterion for distinguishing mental entities from nonmental ones, and defend it from likely sorts of objections. By the phrase ‘criterion of the mental’ I mean a set of conditions which is necessary and sufficient for an entity's being mental (or psychological).
On Showing Invalidity
Authors: McKay Thomas J.
Published: November 2014

In studying logic, one learns how to establish that a conclusion follows from a set of premises. Those arguments that exhibit one of the valid forms of the deductive system under study are valid. There may be questions about what forms are exhibited by various arguments - Is this English conditional (or any other) really truth-functional? Is this disjunction really inclusive? Are the English predicates used with uniform meaning? - but none of these problems undermine the claim that if an argument exhibits a valid form of a system for deductive logic, then that argument is valid.

When we move on to study invalidity, however, we find that the situation is not parallel. Every argument is an instance of some invalid argument forms, and we cannot say that every instance of every invalid form is invalid.
Could We be Brains in a Vat?
Authors: Smith Peter
Published: November 2014

The course of my experience is quite consistent with the hypothesis that it is being produced by a mad scientist who is feeding into my sensory receptors entirely delusive stimuli. Indeed, I could at this very moment be nothing more than a brain floating in a vat of nutrients, my nerve ends linked up to some infernal apparatus by means of which my unknown deceiver induces in me utterly erroneous beliefs about the world.

So begins a familiar line of thought which dramatizes an equally familiar sceptical problem about the relation between our experiences and the world. However, Hilary Putnam has recently offered a marvellously ambitious argument which is intended to kill stone-dead the philosophical fantasy that we might be deluded brains in a vat.
Imagining Kyrgyzstan's nationhood and statehood: reactions to the 2010 Osh violence
Authors: Wilkinson Cai
Published: November 2014

This article explores the tensions inherent in how Kyrgyzstan's nationhood and statehood have been imagined and practised via an analysis of local reactions to the findings of the Kyrgyzstan Inquiry Commission's (KIC) investigation into the 2010 Osh violence and in particular the threat narrative that developed in opposition to the investigation. In the wake of the clashes that erupted in Osh in June 2010, a recurrent theme was calls from the international community for an independent investigation. Within Kyrgyzstan, however, some politicians argued that investigations violated the republic's sovereignty. Despite local reluctance, a number of investigations did subsequently take place. Yet the reports of the respective investigations did little to quell controversy, with the KIC report being strongly criticized and declared a threat to national security. The strength of feeling demonstrated by this reaction was indicative of long-standing and unresolved tensions in Kyrgyzstan between international and local imaginings of nationhood and statehood. The article concludes by arguing that nationhood and statehood need to be reimagined to focus on reestablishing state-society relations by both local and international actors in order for Kyrgyzstan to begin repairing the already fragile sociopolitical relationships that were grievously damaged by the violence and the subsequent investigations.
Molecular mechanisms underlying the reception and transmission of sour taste information
Authors: Ishimaru Yoshiro
Published: November 2014

Taste enables organisms to determine the properties of ingested substances by conveying information regarding the five basic taste modalities: sweet, salty, sour, bitter, and umami. The sweet, salty, and umami taste modalities convey the carbohydrate, electrolyte, and glutamate content of food, indicating its desirability and stimulating appetitive responses. The sour and bitter modalities convey the acidity of food and the presence of potential toxins, respectively, stimulating aversive responses to such tastes. In recent years, the receptors mediating sweet, bitter, and umami tastes have been identified as members of the T1R and T2R G-protein-coupled receptor families; however, the molecular mechanisms underlying sour taste detection have yet to be clearly elucidated. This review covers the molecular mechanisms proposed to mediate the detection and transmission of sour stimuli, focusing on polycystic kidney disease 1-like 3 (Pkd1l3), Pkd2l1, and carbonic anhydrase 4 (Car4).
Respiratory Syncytial Virus Genomic Load and Disease Severity Among Children Hospitalized With Bronchiolitis: Multicenter Cohort Studies in the United States and Finland
Authors: Hasegawa Kohei , Jartti Tuomas , Mansbach Jonathan M. , Laham Federico R. , Jewell Alan M. , Espinola Janice A. , Piedra Pedro A. , Camargo Carlos A.
Published: November 2014

Background

 We investigated whether children with a higher respiratory syncytial virus (RSV) genomic load are at a higher risk of more-severe bronchiolitis.

Methods

> Two multicenter prospective cohort studies in the United States and Finland used the same protocol to enroll children aged <2 years hospitalized for bronchiolitis and collect nasopharyngeal aspirates. By using real-time polymerase chain reaction analysis, patients were classified into 3 genomic load status groups: low, intermediate, and high. Outcome measures were a length of hospital stay (LOS) of ≥3 days and intensive care use, defined as admission to the intensive care unit or use of mechanical ventilation.

Results

 Of 2615 enrolled children, 1764 (67%) had RSV bronchiolitis. Children with a low genomic load had a higher unadjusted risk of having a length of stay of ≥3 days (52%), compared with children with intermediate and those with high genomic loads (42% and 51%, respectively). In a multivariable model, the risk of having a length of stay of ≥3 days remained significantly higher in the groups with intermediate (odds ratio [OR], 1.43; 95% confidence interval [CI], 1.20–1.69) and high (OR, 1.58; 95% CI, 1.29–1.94) genomic loads. Similarly, children with a high genomic load had a higher risk of intensive care use (20%, compared with 15% and 16% in the groups with low and intermediate genomic loads, respectively). In a multivariable model, the risk remained significantly higher in the group with a high genomic load (OR, 1.43; 95% CI, 1.03–1.99).

Conclusion

 Children with a higher RSV genomic load had a higher risk for more-severe bronchiolitis.