bluuebunny/crossref_metadata_2025 huggingface dataset:
Systematic studies of the nucleation and growth of ultrananocrystalline diamond films on silicon substrates coated with a tungsten layer
Authors: Chu Yueh-Chieh , Tu Chia-Hao , Jiang Gerald , Chang Chi , Liu Chuan-pu , Ting Jyh-Ming , Lee Hsin-Li , Tzeng Yonhua , Auciello Orlando
Published: June 2012

We report on effects of a tungsten layer deposited on silicon surface on the effectiveness for diamond nanoparticles to be seeded for the deposition of ultrananocrystalline diamond (UNCD). Rough tungsten surface and electrostatic forces between nanodiamond seeds and the tungsten surface layer help to improve the adhesion of nanodiamond seeds on the tungsten surface. The seeding density on tungsten coated silicon thus increases. Tungsten carbide is formed by reactions of the tungsten layer with carbon containing plasma species. It provides favorable (001) crystal planes for the nucleation of (111) crystal planes by Microwave Plasma Enhanced Chemical Vapor Deposition (MPECVD) in argon diluted methane plasma and further improves the density of diamond seeds/nuclei. UNCD films grown at different gas pressures on tungsten coated silicon which is pre-seeded by nanodiamond along with heteroepitaxially nucleated diamond nuclei were characterized by Raman scattering, field emission-scanning electron microscopy, and high resolution-transmission electron microscopy.
Quasiperiodic solutions of Jaulent-Miodek equations with a negative flow
Authors: Xue Bo , Geng Xianguo , Li Fang
Published: June 2012

A hierarchy of new nonlinear evolution equations is proposed, which are composed of the positive and negative Jaulent-Miodek flows. Based on the theory of algebraic curve, the corresponding flows are straightened under the Abel-Jacobi coordinates. The meromorphic function ϕ, the Baker-Akhiezer vector \documentclass[12pt]{minimal}\begin{document}$\bar{\psi }$\end{document}ψ¯, and the hyperelliptic curve \documentclass[12pt]{minimal}\begin{document}$\mathcal {K}_n$\end{document}Kn are introduced by which quasiperiodic solutions of the first two nonlinear evolution equations in the hierarchy are constructed according to the asymptotic properties and the algebro-geometric characters of ϕ, \documentclass[12pt]{minimal}\begin{document}$\bar{\psi }$\end{document}ψ¯, and \documentclass[12pt]{minimal}\begin{document}$\mathcal {K}_n$\end{document}Kn.
Optical and magnetic properties of Cr-doped ZnS nanocrystallites
Authors: Zeng Xiaoling , Zhang Jiye , Huang Feng
Published: June 2012

Cr-doped ZnS (molar Cr:(Cr + Zn) between 0.51% and 19.69%) nanocrystallites have been prepared through co-precipitation method. The x-ray diffraction, transmission electron microscopy, and selected area electron diffraction results show that all the samples are in sphalerite structure with average particle size about 3 nm. No impurity phase relating to Cr element is found in all the samples. X-ray photoelectron spectroscopy spectra reveal that Cr was incorporated into ZnS lattice as Cr3+. It can be seen in the UV-visible absorption spectra that, besides the intrinsic band-gap absorption of ZnS below 370 nm, there are another two absorption bands (at 425 nm and 595 nm, respectively) in the visible light range, which are the characteristic bands of Cr3+. Photoluminescence spectroscopy was also used to characterize corresponding luminescence properties of the nanocrystallites. The band-edge emission in photoluminescence spectroscopy exhibits blue-shift as the concentration of Cr increases, and several emission peaks concerned with surface states and zinc vacancies were found in the wavelength range of 400 nm ∼ 500 nm. It is confirmed that Cr doping will bring about a considerable amount of zinc vacancies. Magnetic measurements indicated that all the samples are paramagnetic and the calculated effective magnetic moments  μeff of Cr3+ were close to the theoretical value of 3.87 μB. Accordingly, it seems that zinc vacancies give no contribution to the overall magnetic response of the samples.
Analysis of electron dynamics in non-ideal Penning traps
Authors: Coppa G. , D’Angola A. , Mulas R.
Published: June 2012

Penning traps that are used for particular applications, such as in ion pump technology, Larmor, bouncing, and diocotron frequencies, can be of the same order of magnitude. The paper deals with the dynamics of electrons confined in such devices starting from the study of the properties of the trajectories. In cases of interest, in which electron-neutral collision frequency is much smaller with respect to the characteristic frequencies of the motion, suitable time averages of the trajectories are introduced in order to simplify the analysis of the problem. In the work, time averages have been calculated in a simple way by using an approximate r–z decoupling of the effective potential. Results obtained with the method are presented and discussed in both linear and nonlinear regimes.
Influence of small rings on the thermodynamics of equilibrium self-assembly
Authors: Freed Karl F.
Published: June 2012

The competition between the formation of linear chain clusters and ring structures in an equilibrium self-assembling system is reexamined by developing a new Flory-Huggins type theory that combines an estimate for the loss of configurational entropy ΔSring upon ring formation with the standard treatment of the free energy of a polydisperse solution of linear chains. The excess entropy of ring formation ΔSring is obtained from an analytical fit to exact enumeration data for self-avoiding chains and rings with 30 or fewer steps on a cubic lattice. Illustrative calculations of the spinodal curves and the extent and the average degree of self-assembly highlight the physical conditions for which the cyclic structures impact the thermodynamic characterization of equilibrium self-assembling systems.
Interfacial slip friction at a fluid-solid cylindrical boundary
Authors: Kannam Sridhar Kumar , Todd B. D. , Hansen J. S. , Daivis Peter J.
Published: June 2012

Recently we proposed a method to calculate the interfacial friction coefficient between fluid and solid at a planar interface. In this work we extend the method to cylindrical systems where the friction coefficient is curvature dependent. We apply the method to methane flow in carbon nanotubes, and find good agreement with non-equilibrium molecular dynamics simulations. The proposed method is robust, general, and can be used to predict the slip for cylindrical nanofluidic systems.
De-perturbative corrections for charge-stabilized double ionization potential equation-of-motion coupled-cluster method
Authors: Kuś Tomasz , Krylov Anna I.
Published: June 2012

Charge stabilization improves the numeric performance of double ionization potential equation-of-motion (EOM-DIP) method when using unstable (autoionizing) dianion references. However, the stabilization potential introduces an undesirable perturbation to the target states’ energies. Here we introduce and benchmark two approaches for removing the perturbation caused by the stabilization. The benchmark calculations of excitation energies in selected diradicals illustrate that the so-called core correction based on evaluating the perturbation in a small basis set is robust and yields reliable EOM-DIP values, i.e., the errors of 0.0–0.3 eV against a similar-level coupled-cluster approach.
Focus shift photothermal method for thermal diffusivity mapping
Authors: Mingolo N. , Martínez O. E.
Published: June 2012

In this work, we present a photothermal technique that measures at microscopic spatial scales the curvature of the surface of the sample due to the thermal expansion produced by a focused modulated laser beam. A modulated pump beam heats the sample surface and a probe beam delivered through the same optical fiber and slightly defocused probes the curvature, by analyzing the power collected by the same optical fiber. The collected power depends on the defocusing produced by the curvature of the surface induced by the thermal expansion. The phase delay is directly related to the thermal diffusivity of the sample at the impinging location. The scheme is based on the use of photonic technology borrowed from the optical communications field. In this way, the setup results extremely robust, both lasers (pump and probe) are inherently collinear, as they emerge from the same single mode fiber, and the detection is made through the same optical fiber.
Simulation of trap-assisted tunneling effect on characteristics of gallium nitride diodes
Authors: Sakowski Konrad , Marcinkowski Leszek , Krukowski Stanislaw , Grzanka Szymon , Litwin-Staszewska Elzbieta
Published: June 2012

In this paper, simulations of I-V characteristics and band structures of magnesium and silicon doped gallium nitride diodes are presented. The numerical algorithm is based on the drift-diffusion semi-classic model, with the van Roosbroeck differential equation system involved. The model accounts for trap-assisted tunneling, which provides better agreement between the predicted and experimental I-V characteristics of p-n junctions in the low-bias range. We have performed one-dimensional simulations of devices. We compare the results with the results obtained from the standard drift-diffusion model. It is shown that taking the trap-assisted tunneling into account leads to good agreement with experimental data. We also demonstrate that a high doping of the p-n junctions may significantly increase the nonradiative recombination rate due to the prescribed effect.
Experimental and analytical modeling of resonant permittivity and permeability in ferroelectric-ferrite composites in microwave range
Authors: Ciomaga Cristina E. , Balmus Sorin B. , Dumitru Ioan , Mitoseriu Liliana
Published: June 2012

The ferroelectric-magnetic composite materials are very suitable for designing and producing microwave devices and components, due to their dielectric and magnetic properties. For microwave antennas, sensors, resonators, oscillators, filters, phase shifters, attenuators, and amplifiers, the output and input impedances, the resonance frequencies, the quality factor (the losses), and the attenuation or the amplification can be very easily adjusted by modifying the dielectric permittivity or/and the magnetic permeability. This is possible by a right choice of the ratio between the ferroelectric and magnetic phases in the composite material. Therefore, it is highly important to accurately determine these characteristics of the composite material in microwave range.
Diffusive model of current-in-plane-tunneling in double magnetic tunnel junctions
Authors: Clement P.-Y. , Ducruet C. , Baraduc C. , Chshiev M. , Diény B.
Published: June 2012

We propose a model that describes current-in-plane tunneling transport in double barrier magnetic tunnel junctions in diffusive regime. Our study shows that specific features appear in double junctions that are described by introducing two typical length scales. The model may be used to measure the magnetoresistance and the resistance area product of both barriers in unpatterned stacks of double barrier magnetic tunnel junctions.
Understanding the effect of the layer-to-layer distance on Li-intercalated graphite
Authors: Xu B. , Wu M. S. , Liu G. , Ouyang C. Y.
Published: June 2012

The lithium ion dynamics in graphite, an important anode material for lithium ion batteries, is strongly related with the layer-to-layer distance (d-spacing) and the stacking modes of graphite. We studied these relationships by first-principles calculations. It is found that a larger d-spacing results in the easier transformation of the stacking mode from A-B stacking to A-A stacking when lithium atoms are inserted. This transformation is unfavorable to the lithium diffusion because of the larger diffusion energy barrier for lithium in A-A stacking graphite compared to that in A-B one. On the other hand, as the d-spacing increases, the diffusion energy barrier for lithium in A-A stacking graphite decreases substantially, thus being favorable to the lithium diffusion. These results give a better understanding of the lithium ion dynamics in graphite, and show that it is possible to optimize the lithium ion dynamics in graphite by properly adjusting the d-spacing.
Direct measurement of surface states density and energy distribution in individual InAs nanowires
Authors: Halpern E. , Elias G. , Kretinin A. V. , Shtrikman H. , Rosenwaks Y.
Published: June 2012

InAs nanowires are candidates for future high-speed electronic and optoelectronic applications due to their high electron mobility and large coherence length. However, InAs surfaces are known to possess a high concentration of donor-type surface states, which results in an electron accumulation layer and, consequently, Fermi level pinning. Since the surface to volume ratio in nanowires is very large, the effect of surface states is greatly enhanced. We present a method for directly determining the density and energy distribution of single nanowire surface states using Kelvin probe force microscopy measured on a nanowire field-effect transistor and interpreted by electrostatic modeling. Here, the method is applied to individual InAs nanowires, which similarly to bulk InAs exhibit a prominent accumulation layer consisting of a large concentration of donor-type surface states. Nevertheless, due to the small diameter of the nanowires, the electron accumulation and Fermi level pinning take place within the entire nanowire.
Finite-time stochastic outer synchronization between two complex dynamical networks with different topologies
Authors: Sun Yongzheng , Li Wang , Zhao Donghua
Published: June 2012

In this paper, the finite-time stochastic outer synchronization between two different complex dynamical networks with noise perturbation is investigated. By using suitable controllers, sufficient conditions for finite-time stochastic outer synchronization are derived based on the finite-time stability theory of stochastic differential equations. It is noticed that the coupling configuration matrix is not necessary to be symmetric or irreducible, and the inner coupling matrix need not be symmetric. Finally, numerical examples are examined to illustrate the effectiveness of the analytical results. The effect of control parameters on the settling time is also numerically demonstrated.
Fabrication and characterization of a silicon metal-oxide-semiconductor based triple quantum dot
Authors: Pan H. , House M. G. , Hao X. , Jiang H. W.
Published: June 2012

We fabricate electrostatically defined, few-electron triple quantum dot (TQD) devices in a silicon metal-oxide-semiconductor structure and obtain stability diagrams in the few-electron regime through charge detection by a nearby quantum point contact. We demonstrate the tunability of the TQD by achieving the quadruple points where all three dots are on resonance. The tuning evolutions are shown to be consistent with a constant interaction model. We identify quantum cellular automata phenomena near the quadruple point.
Spatially dependent sensitivity of superconducting meanders as single-photon detectors
Authors: Berdiyorov G. R. , Milošević M. V. , Peeters F. M.
Published: June 2012

The photo-response of a thin current-carrying superconducting stripe with a 90° turn is studied within the time-dependent Ginzburg-Landau theory. We show that the photon acting near the inner corner (where the current density is maximal due to the current crowding [J. R. Clem and K. K. Berggren, Phys. Rev. B 84, 174510 (2011)]) triggers the nucleation of superconducting vortices at currents much smaller than the expected critical one, but does not bring the system to a higher resistive state and thus remains undetected. The transition to the resistive state occurs only when the photon hits the stripe away from the corner due to there uniform current distribution across the sample, and dissipation is due to the nucleation of a kinematic vortex-antivortex pair near the photon incidence. We propose strategies to account for this problem in the measurements.
Ion stochastic heating by obliquely propagating magnetosonic waves
Authors: Gao Xinliang , Lu Quanming , Wu Mingyu , Wang Shui
Published: June 2012

The ion motions in obliquely propagating Alfven waves with sufficiently large amplitudes have already been studied by Chen et al. [Phys. Plasmas 8, 4713 (2001)], and it was found that the ion motions are stochastic when the wave frequency is at a fraction of the ion gyro-frequency. In this paper, with test particle simulations, we investigate the ion motions in obliquely propagating magnetosonic waves and find that the ion motions also become stochastic when the amplitude of the magnetosonic waves is sufficiently large due to the resonance at sub-cyclotron frequencies. Similar to the Alfven wave, the increase of the propagating angle, wave frequency, and the number of the wave modes can lower the stochastic threshold of the ion motions. However, because the magnetosonic waves become more and more compressive with the increase of the propagating angle, the decrease of the stochastic threshold with the increase of the propagating angle is more obvious in the magnetosonic waves than that in the Alfven waves.
The q-profile effect on high-order harmonic q = 1 tearing mode generation during sawtooth crashes
Authors: Wang Zheng-Xiong , Wei Lai , Wang Xiaogang
Published: June 2012

The effect of q-profiles on the excitation of high-order harmonic q=1 tearing modes during sawtooth crashes is investigated by a collisionless fluid model with the electron inertia term in Ohm’s law. It is found that for a flat q-profile in the core region, the high-order harmonics, such as m/n=2/2 and/or m/n=3/3 modes, comparable to or stronger than the m/n=1/1 component, can be excited during tokamak sawteeth. The stronger the magnetic shear on the q=1 surface is, the more unstable the higher-m modes are. For smoothly monotonously increased q-profiles, a lower q value on the plasma edge tends to easily excite higher-m harmonics at the same level as the m = 1 mode simultaneously. The spatial characteristics of the eigenmodes in the cases with the typical q-profiles are also discussed. In addition, the basic feature of the magnetic island structures in the nonlinear evolution is numerically obtained, which is consistent qualitatively with the experimentally reconstructed phenomenon.
Selection rule of preferred doping site for n-type oxides
Authors: Li Chong , Li Jingbo , Li Shu-Shen , Xia Jian-Bai , Wei Su-Huai
Published: June 2012

Using first-principles calculations and analysis, we show that to create shallow n-type dopants in oxides, anion site doping is preferred for more covalent oxides such as SnO2 and cation site doping is preferred for more ionic oxides such as ZnO. This is because for more ionic oxides, the conduction band minimum (CBM) state actually contains a considerable amount of O 3s orbitals, thus anion site doping can cause large perturbation on the CBM and consequently produces deeper donor levels. We also show that whether it is cation site doping or anion site doping, the oxygen-poor condition should always be used.
Communication: Probing non-equilibrium vibrational relaxation pathways of highly excited C≡N stretching modes following ultrafast back-electron transfer
Authors: Lynch Michael S. , Slenkamp Karla M. , Khalil Munira
Published: June 2012

Fifth-order nonlinear visible-infrared spectroscopy is used to probe coherent and incoherent vibrational energy relaxation dynamics of highly excited vibrational modes indirectly populated via ultrafast photoinduced back-electron transfer in a trinuclear cyano-bridged mixed-valence complex. The flow of excess energy deposited into four C≡N stretching (νCN) modes of the molecule is monitored by performing an IR pump-probe experiment as a function of the photochemical reaction (τvis). Our results provide experimental evidence that the nuclear motions of the molecule are both coherently and incoherently coupled to the electronic charge transfer process. We observe that intramolecular vibrational relaxation dynamics among the highly excited νCN modes change significantly en route to equilibrium. The experiment also measures a 7 cm−1 shift in the frequency of a ∼57 cm−1 oscillation reflecting a modulation of the coupling between the probed high-frequency νCN modes for τvis < 500 fs.
Asymmetric Pt/Co/Pt-stack induced sign-control of current-induced magnetic domain-wall creep
Authors: Lavrijsen R. , Haazen P. P. J. , Murè E. , Franken J. H. , Kohlhepp J. T. , Swagten H. J. M. , Koopmans B.
Published: June 2012

We report experimentally obtained magnetic domain wall (DW) velocities of current-assisted field-driven DW creep in perpendicularly magnetized Pt/Co/Pt. We have intentionally introduced an asymmetry in the stacks by using different thicknesses of the two Pt layers sandwiching the Co layer. Thereby, it is tested whether conflicting current-induced domain wall motion (CI-DWM) results may be intrinsically related to the basic layout and growth. We sketch a scenario which could be at the basis of contradicting reports in literature where the direction of CI-DWM conflicts with spin-torque-transfer theory, allowing the sign of the current-induced effect on DW motion to be tuned.
Characterisation of lightly oxidised organic aerosol formed from the photochemical aging of diesel exhaust particles
Authors: Kroll Jesse H. , Smith Jared D. , Worsnop Douglas R. , Wilson Kevin R.
Published: June 2012

Environmental contextThe effects of atmospheric fine particulate matter (aerosols) on climate and human health can be strongly influenced by the chemical transformations that the particles undergo in the atmosphere, but these ‘aging’ reactions are poorly understood. Here diesel exhaust particles are aged in the laboratory to better understand how they could evolve in the atmosphere, and subtle but unmistakable changes in their chemical composition are found. These results provide a more complete picture of the atmospheric evolution of aerosols for inclusion in atmospheric models.
AbstractThe oxidative aging of the semivolatile fraction of diesel exhaust aerosol is studied in order to better understand the influence of oxidation reactions on particle chemical composition. Exhaust is sampled from an idling diesel truck, sent through a denuder to remove gas-phase species and oxidised by hydroxyl (OH•) radicals in a flow reactor. OH• concentrations are chosen to approximately match the OH• exposures a particle would experience over its atmospheric lifetime. Evolving particle composition is monitored using aerosol mass spectrometry in two different modes, electron impact ionisation (EI) for the measurement of elemental ratios and vacuum ultraviolet (VUV) photoionisation for the measurement of molecular components. Changes to mass spectra in both modes indicate major changes to particle composition over the range of OH• exposures studied. The product aerosol is only lightly oxidised (O/C < 0.3), suggesting an intermediate oxidation state between primary organics and the highly oxidised organic aerosol observed in the atmosphere. These lightly oxidised organics appear to be composed of secondary organic aerosol from semivolatile species, as well as from heterogeneously oxidised particle-phase organics. Key chemical characteristics (elemental ratios, oxidation kinetics and mass spectrometric features) of the reaction system are examined in detail. Similarities between this laboratory-generated aerosol and ‘hydrocarbon-like organic aerosol’ (HOA) reported in ambient studies suggest that HOA might not be entirely primary in origin, as is commonly assumed, but rather might include a significant secondary component.
Secondary organic aerosol formation from methacrolein photooxidation: roles of NOx level, relative humidity and aerosol acidity
Authors: Zhang Haofei , Lin Ying-Hsuan , Zhang Zhenfa , Zhang Xiaolu , Shaw Stephanie L. , Knipping Eladio M. , Weber Rodney J. , Gold Avram , Kamens Richard M. , Surratt Jason D.
Published: June 2012

Environmental contextSecondary organic aerosols formed from the oxidation of volatile organic compounds make a significant contribution to atmospheric particulate matter, which in turn affects both global climate change and human health. We investigate the mechanisms of formation and the chemical properties of secondary organic aerosols derived from isoprene, the most abundant non-methane-based, volatile organic compound emitted into the Earth’s atmosphere. However, the exact manner in which these aerosols are formed, and how they are affected by environmental conditions, remains unclear.
AbstractSecondary organic aerosol (SOA) formation from the photooxidation of methacrolein (MACR) was examined in a dual outdoor smog chamber under varied initial nitric oxide (NO) levels, relative humidities (RHs) and seed aerosol acidities. Aerosol sizing measurements and off-line chemical analyses by gas chromatography/mass spectrometry and ultra performance liquid chromatography/electrospray ionisation high-resolution quadrupole time-of-flight mass spectrometry (UPLC/ESI-HR-Q-TOFMS) were used to characterise MACR SOA formation. Results indicate that both SOA mass and chemical composition largely depend on the initial MACR/NO ratio and RH conditions. Specifically, at lower initial NO levels (MACR/NO = ~2.7) more substantial SOA is formed under dry conditions (5–20 % RH) compared to wet conditions (30–80 % RH). However, at higher initial NO levels (MACR/NO = ~0.9), the maximum SOA formation was marginally higher under wet conditions. Furthermore, UPLC/ESI-HR-Q-TOFMS data suggest that most particle-phase oligomers, which have been previously observed to form from the oxidation of methacryloylperoxynitrate, were enhanced under dry conditions. In addition to 2-methylglyceric acid and organosulfates derived from MACR oxidation, a nitrogen-containing organic tracer compound was found to form substantially in both chamber-generated and ambient aerosol samples collected from downtown Atlanta, GA, during the 2008 August Mini-Intensive Gas and Aerosol Study (AMIGAS). Moreover, increasing aerosol acidity because of additional sulfuric acid appears to have a negligible effect on both SOA mass and most SOA constituents. Nevertheless, increased RH and aerosol acidity were both observed to enhance organosulfate formation; however, elevating RH mediates organosulfate formation, suggesting that wet sulfate aerosols are necessary to form organosulfates in atmospheric aerosols.
New Essentialism in Biology
Authors: Rieppel Olivier
Published: June 2012

The architects of the modern synthesis banned essentialism from evolutionary theory. This rejection of essentialism was motivated by Darwin's theory of natural selection, and the continuity of evolutionary transformation. Contemporary evolutionary biology witnesses a renaissance of essentialism in three contexts: “origin essentialism” with respect to species and supraspecific taxa, the bar coding of species on the basis of discontinuities of DNA variation between populations, and the search for laws of evolutionary developmental biology. Such “new essentialism” in contemporary biology must be of a new kind that accommodates relational (extrinsic) properties as historical essences and cluster concepts of natural kinds.
Can Entanglement Be Destroyed by Any Local Operation in Relativistic Quantum Field Theory?
Authors: Valente Giovanni
Published: June 2012

This article investigates the nature of entangled correlations in algebraic quantum field theory (AQFT). We define a notion of local disentanglement, expressing the possibility of destroying entanglement by means of local operations. Contrary to the case of ordinary quantum mechanics, local disentanglement cannot be achieved in general in relativistic quantum field theory. However, we show that if the split property holds, there exists a local operation that can destroy entanglement between spacelike-separated quantum field systems.
Hume, Norton, and Induction without Rules
Authors: Kelly Thomas
Published: June 2012

Does Hume's skeptical critique of inductive reasoning depend for its force on the assumption that such reasoning is a matter of following general rules? I explore this question in connection with John Norton's “Material Theory of Induction.”
Data, Phenomena, Signal, and Noise
Authors: Woodward James
Published: June 2012

This essay attempts to provide additional motivation for the data/phenomena framework advocated in Bogen and Woodward, “Saving the Phenomena” (1988).
Einstein's Dissatisfaction with Nonrelativistic Quantum Mechanics and Relativistic Quantum Field Theory
Authors: Rédei Miklós
Published: June 2012

It is argued that in his critique of standard nonrelativistic quantum mechanics Einstein formulated three requirements as necessary for a physical theory to be compatible with the field-theorectical paradigm, and it is shown that local, relativistic, algebraic quantum field theory typically satisfies those criteria—although, there are still open questions concerning the status of operational separability of quantum systems localized in spacelike separated space-time regions. It is concluded that local algebraic quantum field theory can be viewed as a research program that Einstein suggested informally in 1948 and that was realized only later in mathematical physics.
Prosthetic Models
Authors: Craver Carl F.
Published: June 2012

What are the relative epistemic merits of building prosthetic models versus building nonprosthetic models and simulations? I argue that prosthetic models provide a sufficient test of affordance validity, that is, of whether the target system affords mechanisms that can be commandeered by a prosthesis. In other respects, prosthetic models are epistemically on par with nonprosthetic models. I focus on prosthetics in neuroscience, but the results are general. The goal of understanding how brain mechanisms work under ecologically and physiologically relevant conditions is narrow compared to the search for maker's knowledge about how the brain can be made to work for us.
For Universal Rules, Against Induction
Authors: Worrall John
Published: June 2012

This essay criticizes John Norton's 2010 defense of the thesis that “all induction is local.” Norton's local inductions are bound, if cogent, to involve general principles, and the need to accredit these general principles threatens to lead to all the usual problems associated with the ‘problem of induction’. Norton, in fact, recognizes this threat, but his responses are inadequate. The right response involves not induction but a sophisticated version of hypothetico-deduction. Norton's secondary thesis—that if there is a general account of cogent scientific reasoning, then it is certainly not the one supported by personalist Bayesians—is also criticized.
Thermodynamics in Wilhelm Ostwald's Physical Chemistry
Authors: Deltete Robert J.
Published: June 2012

This essay focuses on the place of the second law of thermodynamics in Wilhelm Ostwald's physical chemistry. After a brief introduction to his energetic theory, which was supposed to be a generalization of thermodynamics, I contrast Ostwald's understanding of the second law, which ignored entropy and irreversibility, with Max Planck's, which emphasized both. I then consider how Ostwald sought to develop physical chemistry without any concern for irreversibility and little concern for entropy, and I argue that he was mistaken.
Scientific Realism: Between Platonism and Nominalism
Authors: Psillos Stathis
Published: June 2012

In this paper, I discuss the prospects of nominalistic scientific realism (NSR) and show that it fails on many counts. In section 2, I discuss what is required for NSR to get off the ground. In section 3, I question the idea that theories have well-defined nominalistic content and the idea that causal activity is a necessary condition for commitment to the reality of an entity. In section 4, I challenge the notion of nominalistic adequacy of theories.
A Non-Newtonian Newtonian Model of Evolution: The ZFEL View
Authors: Brandon Robert N.
Published: June 2012

Recently philosophers of biology have argued over whether or not Newtonian mechanics provides a useful analogy for thinking about evolutionary theory. For philosophers, the canonical presentation of this analogy is Sober's. Matthen and Ariew and Walsh, Lewins, and Ariew argue that this analogy is deeply wrong-headed. Here I argue that the analogy is indeed useful, however, not in the way it is usually interpreted. The Newtonian analogy depends on having the proper analogue of Newton's First Law. That analogue is what McShea and Brandon call the Zero Force Evolutionary Law (ZFEL). According to the ZFEL, change, not stasis, is the default state of evolutionary systems.
Three distinct hydrogen sensing responses of palladium line patterns generated by femtosecond laser direct writing
Authors: Ren Shoutian , Wang Qiang , Wang Yanshen , Qu Shiliang
Published: June 2012

Application of a palladium nanostructure in hydrogen detection is a focus of current research due to its high sensitivity. In this paper, palladium nanometre films are fabricated using femtosecond laser decomposition of palladium acetate films. Their hydrogen sensing characteristics are studied as a function of hydrogen concentration and morphologies of palladium films. As palladium film morphologies vary from continuous to partially continuous and then to discontinuous, the corresponding hydrogen response changes from normal to pulse-like and then to switch-like. Their response characteristics are determined by the different combined effects of the formation of high-resistance palladium hydrogen and the corresponding narrowing of nanogaps between palladium nanoparticles.
Influence of exponentially increasing surface elasticity on the piezoelectric potential of a bent ZnO nanowire
Authors: Yao Haiyan , Yun Guohong , Bai Narsu
Published: June 2012

The influence of surface elasticity on the piezoelectric potential of a bent ZnO nanowire is investigated using a modified core–shell (MC–S) model in which it is assumed that the elasticity in the shell (surface region) is an exponentially increasing function. Specifically, we analyse the effects of the nanowire radius and applied force on the piezoelectric potential with and without the surface elasticity effect, as well as the influence of surface elasticity on the deflection of the nanowire. The results demonstrate that both the nanowire radius and the applied force are key factors affecting the piezoelectric potential, and that the effect of surface elasticity is even more important, which should not be ignored, especially for dimensions below 100 nm.
Perception
Authors: Matilal Bimal Krishna
Published: June 2012

This book is a defence of the form of realism which stands closest to that upheld by the Nyāya–Vaíṣsika school in classical India. The book presents the Nyāya view and critically examines it against that of its traditional opponent, the Buddhist version of phenomenalism and idealism. This reconstruction of Nyāya arguments meets not only traditional Buddhist objections but also those of modern sense-data representationalists.
Phosphodiesterase 5 inhibition protects against increased intra‐abdominal pressure‐induced renal dysfunction in experimental congestive heart failure
Authors: Bishara Bishara , Abu‐Saleh Niroz , Awad Hoda , Ghrayeb Nabil , Goltsman Ilia , Aronson Doron , Khamaysi Iyad , Assady Suhair , Armaly Zaher , Haddad Saleem , Haddad Elias , Abassi Zaid
Published: June 2012

Aims

Congestive heart failure (CHF) is associated with impaired renal function. Previously, we have demonstrated that rats with decompensated CHF exhibited exaggerated sensitivity to the adverse renal effects of increased increased intra‐abdominal pressure (IAP) as compared with normal controls. This study tested whether phosphodiesterase 5 (PDE5) inhibition protects against the adverse renal effects of increased IAP in rats with CHF.

Methods and results

Following baseline periods, rats with compensated and decompensated CHF induced by the placement of an aorto‐caval fistula (ACF), rats with myocardial infarction (MI) induced by left anterior descending (LAD) artery ligation, and sham controls were subjected to consecutive IAPs: 7, 10, or 14 mmHg. Urine flow (V), Na+ excretion (UNaV), glomerular filtration rate (GFR), and renal plasma flow (RPF) were determined. The effects of pre‐treatment with tadalafil on the adverse renal effects of IAP were examined in rats with decompensated CHF and MI. Elevation of IAP to 10 and 14 mmHg produced linear reductions in these parameters. Basal renal function and haemodynamics were lower in CHF rats. Decompensated CHF rats and MI rats that were subjected to 10 and 14 mmHg exhibited exaggerated declines in V, UNaV, GFR, and RPF. In contrast, no adverse renal effects were observed in rats with compensated CHF subjected to IAP. Pre‐treatment of decompensated CHF rats and MI rats with tadalafil ameliorated the adverse renal effects of high IAP.

Conclusion

Decompensated CHF and MI rats are vulnerable to the adverse renal effects of IAP. Tadalafil abolishes IAP‐induced renal dysfunction, supporting a therapeutic role for PDE5 inhibition in CHF associated with ascites.
[Ni(MeCN)(H2O)2(NO3)2]·(15-crown-5)·MeCN: detailed study of a four-phase sequence that includes an intermediate modulated phase
Authors: Siegler Maxime A. , Parkin Sean , Brock Carolyn Pratt
Published: June 2012

A sequence of four phases has been found for an acetonitrile-solvated co-crystal with 15-crown-5 of the nickel complex [acetonitrilediaqua-κ1
O-nitrato-κ2
O-nitratonickel(II)]. The structure could be determined at intervals of ca 10 K in the range 90–273 K because crystals remain single through the three transitions. In phase (I) (T ≥ ca 240 K; P21/m, Z′ = ½), there is extensive disorder, which is mostly resolved in phase (III) (ca 230–145 K; P21/c, Z′ = 1). Phase (IV) (ca 145–90 K, and probably below; P\overline 1, Z′ = 2) is ordered. Phase (II) (ca 238–232 K) is modulated, but the satellite reflections are too weak to allow the structure to be determined within its stability range by standard methods. Most crystals that were flash-cooled from room temperature to 90 K have a metastable P21, Z′ = 5 superstructure that (at least in a commensurate approximation) was identified as similar to the structure of phase (II) by comparison of reconstructed reciprocal-lattice slices and by analogy with the phase behavior of the very similar compound [Ni(H2O)6](NO3)2·(15-crown-5)·2H2O [Siegler et al. (2011). Acta Cryst. B67, 486–498]. In the phase (II) structure slab-like regions that are like the disordered phase (I) structure alternate with regions of similar shape and size that are like the more ordered phase (III) structure.
The Effects of Time Budget Pressure and Intentionality on Audit Supervisors' Response to Audit Staff False Sign‐off
Authors: Hyatt Troy A. , Taylor Mark H.
Published: June 2012

Based on theory from the psychology literature and results from prior false sign‐off research, we develop hypotheses and then conduct an experiment to assess the reporting intentions of audit supervisors who discover that a staff member under their supervision has committed false sign‐off. The experiment manipulated the level of time budget pressure on the audit engagement and the staff member's intentionality. Results indicate that audit supervisors are more likely to report the false sign‐off when (1) the audit staff member was working under conditions of low time budget pressure versus high time budget pressure and (2) the staff member committed the false sign‐off intentionally versus unintentionally as a result of confusion over what was expected. The paper concludes with a discussion of its limitations, suggestions for future research, as well as implications for practice.
In a shake of a lamb's tail: using genomics to unravel a cause of chondrodysplasia in Texel sheep
Authors: Zhao X. , Onteru S. K. , Piripi S. , Thompson K. G. , Blair H. T. , Garrick D. J. , Rothschild M. F.
Published: June 2012

Chondrodysplasia in Texel sheep is a recessively inherited disorder characterized by dwarfism and angular deformities of the forelimbs. A genome‐wide association study using the Illumina OvineSNP50 BeadChip on 15 sheep diagnosed as affected and eight carriers descended from three affected rams was conducted to uncover the genetic cause. A homozygous region of 25 consecutive single nucleotide polymorphism (SNP) loci was identified in all affected sheep, covering a region of 1 Mbp on ovine chromosome 4. Seven positional candidate genes – including the solute carrier family 13 (sodium/sulphate symporters), member 1 (SLC13A1) – were identified and used to search for new SNPs for fine mapping of the causal locus. The SLC13A1 gene, encoding a sodium/sulphate transporter, was the primary candidate gene attributable to similar phenotypes observed in the Slc13a1 knockout mouse model. We discovered a 1‐bp deletion of T (g.25513delT) at the 107 bp position of exon 3 in the SLC13A1 gene. Genotyping by direct sequencing and restriction fragment length polymorphism analysis for this mutation showed that all 15 affected sheep were g.25513delT/g.25513delT; the eight carriers were g.25513delT/T and 54 normal controls were T/T. The mutation g.25513delT shifts the open reading frame of SLC13A1 to introduce a stop codon and truncate C‐terminal amino acids. It was concluded that the g.25513delT mutation in the SLC13A1 gene was responsible for the chondrodysplasia seen in these Texel sheep. This knowledge can be used to identify carriers with the defective g.[25513delT] allele to avoid at‐risk matings to improve animal welfare and decrease economic losses.
Genome‐wide association study identifies candidate markers for bull fertility in Holstein dairy cattle
Authors: Peñagaricano F. , Weigel K. A. , Khatib H.
Published: June 2012

The decline in the reproductive efficiency of dairy cattle has become a challenging problem worldwide. Female fertility is now taken into account in breeding goals while generally less attention is given to male fertility. The objective of this study was to perform a genome‐wide association study in Holstein bulls to identify genetic variants significantly related to sire conception rate (SCR), a new phenotypic evaluation of bull fertility. The analysis included 1755 sires with SCR data and 38 650 single nucleotide polymorphisms (SNPs) spanning the entire bovine genome. Associations between SNPs and SCR were analyzed using a mixed linear model that included a random polygenic effect and SNP genotype either as a linear covariate or as a categorical variable. A multiple testing correction approach was used to account for the correlation between SNPs because of linkage disequilibrium. After genome‐wide correction, eight SNPs showed significant association with SCR. Some of these SNPs are located close to or in the middle of genes with functions related to male fertility, such as the sperm acrosome reaction, chromatin remodeling during the spermatogenesis, and the meiotic process during male germ cell maturation. Some SNPs showed marked dominance effects, which provide more evidence for the relevance of non‐additive effects in traits closely related to fitness such as fertility. The results could contribute to the identification of genes and pathways associated with male fertility in dairy cattle.
Genome‐wide association analysis and genetic architecture of egg weight and egg uniformity in layer chickens
Authors: Wolc A. , Arango J. , Settar P. , Fulton J. E. , O’Sullivan N. P. , Preisinger R. , Habier D. , Fernando R. , Garrick D. J. , Hill W. G. , Dekkers J. C. M.
Published: June 2012

The pioneering work by Professor Soller et al., among others, on the use of genetic markers to analyze quantitative traits has provided opportunities to discover their genetic architecture in livestock by identifying quantitative trait loci (QTL). The recent availability of high‐density single nucleotide polymorphism (SNP) panels has advanced such studies by capitalizing on population‐wide linkage disequilibrium at positions across the genome. In this study, genomic prediction model Bayes‐B was used to identify genomic regions associated with the mean and standard deviation of egg weight at three ages in a commercial brown egg layer line. A total of 24 425 segregating SNPs were evaluated simultaneously using over 2900 genotyped individuals or families. The corresponding phenotypic records were represented as individual measurements or family means from full‐sib progeny. A novel approach using the posterior distribution of window variances from the Monte Carlo Markov Chain samples was used to describe genetic architecture and to make statistical inferences about regions with the largest effects. A QTL region on chromosome 4 was found to explain a large proportion of the genetic variance for the mean (30%) and standard deviation (up to 16%) of the weight of eggs laid at specific ages. Additional regions with smaller effects on chromosomes 2, 5, 6, 8, 20, 23, 28 and Z showed suggestive associations with mean egg weight and a region on chromosome 13 with the standard deviation of egg weight at 26–28 weeks of age. The genetic architecture of the analyzed traits was characterized by a limited number of genes or genomic regions with large effects and many regions with small polygenic effects. The region on chromosome 4 can be used to improve both the mean and standard deviation of egg weight by marker‐assisted selection.
Safe prescribing: a titanic challenge
Authors: Routledge Philip A.
Published: June 2012

The challenge to achieve safe prescribing merits the adjective ‘titanic’. The organisational and human errors leading to poor prescribing (e.g. underprescribing, overprescribing, misprescribing or medication errors) have parallels in the organisational and human errors that led to the loss of the Titanic 100 years ago this year. Prescribing can be adversely affected by communication failures, critical conditions, complacency, corner cutting, callowness and a lack of courage of conviction, all of which were also factors leading to the Titanic tragedy. These issues need to be addressed by a commitment to excellence, the final component of the ‘Seven C's’.

Optimal prescribing is dependent upon close communication and collaborative working between highly trained health professionals, whose role is to ensure maximum clinical effectiveness, whilst also protecting their patients from avoidable harm. Since humans are prone to error, and the environments in which they work are imperfect, it is not surprising that medication errors are common, occurring more often during the prescribing stage than during dispensing or administration.

A commitment to excellence in prescribing includes a continued focus on lifelong learning (including interprofessional learning) in pharmacology and therapeutics. This should be accompanied by improvements in the clinical working environment of prescribers, and the encouragement of a strong safety culture (including reporting of adverse incidents as well as suspected adverse drug reactions whenever appropriate). Finally, members of the clinical team must be prepared to challenge each other, when necessary, to ensure that prescribing combines the highest likelihood of benefit with the lowest potential for harm.