bluuebunny/crossref_metadata_2025 huggingface dataset:
Global Trends in Maxillofacial Fractures
Authors: Lee Kai
Published: October 2012

Background

The etiology, demographics, fracture site in facial injury patients have been reported worldwide. However, few studies have attempted to identify changes in maxillofacial fractures over time periods and between countries. The statistics are vastly different due to variations in social, environmental, and cultural factors.

Methods

Data were collected from departmental records between 1996 and 2006 for patients treated at Christchurch Hospital for facial fractures. Variables examined included incidence, demographics, site of fracture, and treatment methods.

Results

A total of 2563 patients presented during the study period, 1158 patients in the first half and 1404 patients in the second half. Male-to-female ratio was 4:1 in both periods and males in 16- to 30-year group accounted for about half of all patients. Interpersonal violence was the most common cause of injuries, and there was a decrease in injuries caused by motor vehicle accidents. Approximately half of all patients required hospitalization and surgery, and the most common method of treatment was open reduction and internal fixation.

Conclusion

Maxillofacial fracture is a common injury in young males following interpersonal violence in New Zealand. Studies in other countries and over different time periods yield interesting differences in the etiology, demographics, and fractures patterns. These are due to environmental, societal, cultural, and legislative differences.
Xenon ultraviolet laser researchers claim success
Authors: Lubkin Gloria B.
Published: October 2012

Stimulated emission from high-pressure xenon has been observed recently in the vacuum ultraviolet by three groups, all of whom believe they have demonstrated laser action. The stimulated transitions occur between the lowest bound diatomic states of xenon and the repulsive ground state. According to one of the experimenters, James Gerardo of Sandia Laboratories, this is the first example of a laser where the lower laser level is not bound. Furthermore, he said, it is the first uv laser that has the potential of being high-powered—10% efficiency is possible. One application that interests Sandia, for example, is that a high-power xenon laser could be useful for laser-induced thermonuclear fusion (see page 46).
Interest grows in synchrotron–radiation sources
Authors: Lubkin Gloria B.
Published: October 2012

The National Science Foundation has just funded a new synchrotron-radiation facility at Stanford University to be open to users throughout the US. The facility, which will use the electron–positron storage ring, SPEAR, is currently operating at 2.6 GeV at the Stanford Linear Accelerator Center. It will produce photons with a critical energy of 3.07 keV with some photon flux up to 20 keV.
How safe are reactor emergency cooling systems?
Authors: Leeper Charles K.
Published: October 2012

The need to increase the nation's electrical energy resources during the coming decades will place heavy demands upon the nuclear power industry. Nuclear power plants, both old and new, must meet Atomic Energy Commission regulations, which include the requirement for an emergency-core-cooling system to control the damage that might result from a loss-of-coolant accident (a “LOCA”). In this article, we will discuss emergency provisions for such accidents, the development and verification of appropriate mathematical models for the processes involved, related experimental programs, and we will assess the progress of the AEC's program in these areas.
Global dynamics for a relativistic charged matter in the presence of a massive scalar field and the presence of a cosmological constant on Bianchi spacetimes
Authors: Noutchegueme Norbert , Nangue Alexis
Published: October 2012

Following a previous work which proved a global in time existence theorem to the coupled Einstein-Maxwell-Massive scalar field which rules the dynamics of a kind of charged pure matter in the presence of a massive scalar field, we study the asymptotic behaviour, the geodesic completeness, and the energy conditions. We prove that, at late times, the mean curvature of the space-time goes to a strictly negative limit and that the three energy conditions are satisfied under some hypotheses.
Extending quantum operations
Authors: Heinosaari Teiko , Jivulescu Maria A. , Reeb David , Wolf Michael M.
Published: October 2012

For a given set of input-output pairs of quantum states or observables, we ask the question whether there exists a physically implementable transformation that maps each of the inputs to the corresponding output. The physical maps on quantum states are trace-preserving completely positive maps, but we also consider variants of these requirements. We generalize the definition of complete positivity to linear maps defined on arbitrary subspaces, then formulate this notion as a semidefinite program, and relate it by duality to approximative extensions of this map. This gives a characterization of the maps which can be approximated arbitrarily well as the restriction of a map that is completely positive on the whole algebra, also yielding the familiar extension theorems on operator spaces. For quantum channel extensions and extensions by probabilistic operations we obtain semidefinite characterizations, and we also elucidate the special case of Abelian inputs or outputs. Finally, revisiting a theorem by Alberti and Uhlmann, we provide simpler and more widely applicable conditions for certain extension problems on qubits, and by using a semidefinite programming formulation we exhibit counterexamples to seemingly reasonable but false generalizations of the Alberti-Uhlmann theorem.
Physical transformations between quantum states
Authors: Huang Zejun , Li Chi-Kwong , Poon Edward , Sze Nung-Sing
Published: October 2012

Given two sets of quantum states {A1, …, Ak} and {B1, …, Bk}, represented as sets as density matrices, necessary and sufficient conditions are obtained for the existence of a physical transformation T, represented as a trace-preserving completely positive map, such that T(Ai) = Bi for i = 1, …, k. General completely positive maps without the trace-preserving requirement, and unital completely positive maps transforming the states are also considered.
Plasma confinement regimes and collective modes characterizing them
Authors: Coppi B. , Zhou T.
Published: October 2012

A unified theory is presented for the modes that are excited at the edge of the plasma column and are important signatures of the advanced confinement regimes into which magnetically confined plasmas can be driven. In particular, the so-called EDA H-Regime, the Elmy H-Regime, and the I-Regime are considered. The modes that are identified theoretically have characteristics that are consistent with or have anticipated those of the modes observed experimentally for each of the investigated regimes. The phase velocities, the produced transport processes, the frequencies, the wavelengths, and the consistency with the direction of spontaneous rotation are the factors considered for comparison with the relevant experiments. The quasi-coherent mode [I. Cziegler, Ph.D. dissertation, Massachusetts Institute of Technology, Cambridge, MA, 2011] that is present in the EDA H-Regime has a phase velocity in the direction of the ion diamagnetic velocity in the plasma reference frame. Consequently, this is identified as a ballooning mode near finite Larmor radius marginal stability involving the effects of transverse ion viscosity and other dissipative effects. In this regime, impurities are driven outward by the combined effects of the local temperature gradients of the impurities and their thermal conductivity, while in the Elmy H-Regime impurities are driven toward the center of the plasma column. In the I-Regimes, the excited “Heavy Particle” modes [B. Coppi and T. Zhou, Phys. Plasmas 19, 012302 (2012); Phys. Lett. A 375, 2916 (2011)] are not of the ballooning kind and are shown to expel the impurities toward the plasma edge in the presence of significant fluctuations. These modes can have a finite frequency of oscillation with a phase velocity in the direction of the electron diamagnetic velocity or they can be nearly purely growing, explaining why there are I-Regimes where fluctuations are not observed. Instead, the modes considered for the Elmy H-Regime are of the ballooning kind. They are driven by the combined effects of the plasma pressure gradient and the magnetic field curvature, are close to conditions under which the acquired growth rates are proportional to half power of the relevant dissipation parameters, involve the effects of finite magnetic diffusivity and finite electron thermal conductivity, and can have phase velocities in either direction.
X-ray diffraction assisted spectroscopy of Rydberg states
Authors: Kirrander Adam
Published: October 2012

X-ray diffraction combined with conventional spectroscopy could provide a powerful means to characterize electronically excited atoms and molecules. We demonstrate theoretically how x-ray diffraction from laser excited atoms can be used to determine electronic structure, including angular momentum composition, principal quantum numbers, and channel populations. A theoretical formalism appropriate for highly excited atoms, and easily extended to molecules, is presented together with numerical results for Xe and H atoms.
The rotational spectra of HD17O and D2
17O: Experiment and quantum-chemical calculations
Authors: Puzzarini Cristina , Cazzoli Gabriele , Gauss Jürgen
Published: October 2012

Guided by theoretical predictions, the rotational spectrum of HD17O was recorded and assigned for the first time, while the measurements for D217O were extended up to the THz region. For both isotopic species, a large portion of the rotational spectrum, from 65 GHz (from 200 GHz for the bideuterated isotopologue) up to 1.6 THz, was investigated, thus allowing the accurate determination of the ground-state rotational and centrifugal-distortion constants. Considering that the rotational spectra of water isotopologues are characterized by a very low density of lines and strong centrifugal-distortion effects, the accurate quantum-chemical prediction of the relevant spectroscopic parameters played a crucial role in the line search and assignment as well as in supporting the fitting procedure. In addition to rotational and centrifugal-distortion constants, the knowledge of the oxygen quadrupole-coupling constants was essential, as the corresponding interaction leads to characteristic features (hyperfine structure) that enabled proper line assignments.
The rigged Hilbert space approach to the Gamow states
Authors: de la Madrid Rafael
Published: October 2012

We use the resonances of the spherical shell potential to present a thorough description of the Gamow (quasinormal) states within the rigged Hilbert space. It will be concluded that the natural setting for the Gamow states is a rigged Hilbert space whose test functions fall off at infinity faster than Gaussians.
Car-Parrinello molecular dynamics study of the uranyl behaviour at the gibbsite/water interface
Authors: Lectez Sébastien , Roques Jérôme , Salanne Mathieu , Simoni Eric
Published: October 2012

The uranyl cation UO22+ adsorption on the basal face of gibbsite is studied via Car-Parrinello molecular dynamics. In a first step, we study the water sorption on a gibbsite surface. Three different sorption modes are observed and their hydrogen bond patterns are, respectively, characterized. Then we investigate the sorption properties of an uranyl cation, in the presence of water. In order to take into account the protonation state of the (001) gibbsite face, both a neutral (001) face and a locally deprotonated (001) face are modeled. In the first case, three adsorbed uranyl complexes (1 outer sphere and 2 inner spheres) with similar stabilities are identified. In the second case, when the gibbsite face is locally deprotonated, two adsorbed complexes (1 inner sphere and 1 outer one) are characterized. The inner sphere complex appears to be the most strongly linked to the gibbsite face.
Chemically transferable coarse-grained potentials from conditional reversible work calculations
Authors: Brini E. , van der Vegt N. F. A.
Published: October 2012

The representability and transferability of effective pair potentials used in multiscale simulations of soft matter systems is ill understood. In this paper, we study liquid state systems composed of n-alkanes, the coarse-grained (CG) potential of which may be assumed pairwise additive and has been obtained using the conditional reversible work (CRW) method. The CRW method is a free-energy-based coarse-graining procedure, which, by means of performing the coarse graining at pair level, rigorously provides a pair potential that describes the interaction free energy between two mapped atom groups (beads) embedded in their respective chemical environments. The pairwise nature of the interactions combined with their dependence on the chemically bonded environment makes CRW potentials ideally suited in studies of chemical transferability. We report CRW potentials for hexane using a mapping scheme that merges two heavy atoms in one CG bead. It is shown that the model is chemically and thermodynamically transferable to alkanes of different chain lengths in the liquid phase at temperatures between the melting and the boiling point under atmospheric (1 atm) pressure conditions. It is further shown that CRW-CG potentials may be readily obtained from a single simulation of the liquid state using the free energy perturbation method, thereby providing a fast and versatile molecular coarse graining method for aliphatic molecules.
Understanding anisotropic growth behavior of hexagonal ice on a molecular scale: A molecular dynamics simulation study
Authors: Seo Myungjoo , Jang Eunseon , Kim Kyeongjin , Choi Saehyun , Kim Jun Soo
Published: October 2012

Although distinct growth behaviors on different faces of hexagonal ice have long been suggested, their understanding on a molecular scale has been hampered due to experimental difficulties near interfaces. We present a molecular dynamics simulation study to unravel the molecular origin of anisotropy in the growth kinetics of hexagonal ice by visualizing the formation of transient water structures in the growing ice interface. During ice growth, the formation of transient structures and their rearrangement to the final ice configuration are observed irrespective of growth direction. However, we find that their structure and duration differ significantly depending on growth direction. In the direction perpendicular to the basal face of hexagonal ice along which growth occurs most slowly, a two-dimensional transient structure, which is formed by competing hexagonal and cubic arrangements within the same layer, persists for a significant period of time, contrasted with short-lived transient structures in other directions. This observation of such transient water structures and their rearrangement during ice growth provides a clear explanation of different growth rates on each face of hexagonal ice on a molecular scale.
Analytical methods for the mechanics of graphene bubbles
Authors: Yue Kaimin , Gao Wei , Huang Rui , Liechti Kenneth M.
Published: October 2012

When placing a graphene membrane on a substrate, gas molecules may be trapped underneath to form bubbles. The size of a graphene bubble (e.g., diameter and height) depends on the number of gas molecules that are trapped, the elastic properties of graphene, and the interfacial adhesion between graphene and the substrate. A mechanics analysis of such graphene bubbles is conducted via membrane and nonlinear plate theories, so that the interfacial adhesion can be determined directly from measurements of the bubble size. A comparison of the results from these two models establishes that the membrane analysis is sufficient for relatively large bubbles. The adhesion energy of mechanically exfoliated graphene on silicon oxide is extracted from two reported data sets using the simple membrane theory, and the values range from 0.097 to 0.43 J/m2. Moreover, the strain distribution of the graphene bubbles and transport of gas molecules among the bubbles are discussed.
Raman spectroscopy determination of the Debye temperature and atomic cohesive energy of CdS, CdSe, Bi2Se3, and Sb2Te3 nanostructures
Authors: Yang X. X. , Zhou Z. F. , Wang Y. , Jiang R. , Zheng W. T. , Sun Chang Q.
Published: October 2012

We have formulated the size and temperature dependence of the phonon relaxation dynamics for CdS, CdSe, Bi2Se3, and Sb2Te3 nanostructures based on the framework of bond order–length–strength correlation, core-shell configuration, and local bond averaging approach. The Raman shifts are correlated directly to the identities (nature, order, length, and energy) of the representative bond of the specimen without needing involvement of the Grüneisen mode parameters or considering the processes of phonon decay or multi-phonon resonant scattering. Quantitative information of the Debye temperature, the atomic cohesive energy, the reference frequencies from which the Raman shifts proceed, and the effective coordination numbers of the randomly sized particles, as well as the length and energy of the representative bond, has been obtained. It is clarified that the size-induced phonon softening arises intrinsically from the cohesive weakening of the undercoordinated atoms in the skin up to three atomic layers and the thermally derived phonon softening results from the thermally lengthening and weakening of bonds. Developed approach empowers the Raman technique in deriving quantitative and direct information regarding bond stiffness relaxation with applied stimuli such as coordination, mechanical, thermal, and chemical environment, which are crucial to practical applications.
Influence of microstructure and interfacial strain on the magnetic properties of epitaxial Mn3O4/La0.7Sr0.3MnO3 layered-composite thin films
Authors: Mukherjee Devajyoti , Bingham Nicholas , Hordagoda Mahesh , Phan Manh-Huong , Srikanth Hariharan , Witanachchi Sarath , Mukherjee Pritish
Published: October 2012

Epitaxial Mn3O4/La0.7Sr0.3MnO3 (Mn3O4/LSMO) bilayer thin films were grown on lattice-matched single crystal substrates of SrTiO3 (STO) (100) and MgO (100), with Mn3O4 as the top layer, using a pulsed laser deposition technique. X-ray diffraction (XRD) patterns revealed the single crystalline nature and epitaxial relationship between the layers. A detailed analysis of strains using XRD asymmetric/symmetric scans indicated an increasing in-plane compressive strain in the LSMO layer with increasing thicknesses of the Mn3O4 layer, resulting in a tetragonal distortion of the LSMO lattice in the Mn3O4/LSMO films in comparison to the tensile strains in LSMO single-layer films grown on both STO and MgO substrates. Cross-sectional high resolution transmission electron microscope (HRTEM) images showed atomically sharp interfaces in all films. However, as opposed to a flat interface between LSMO and STO, the Mn3O4 and LSMO interface was undulating and irregular in the bilayer films. Magnetic measurements revealed that relative to LSMO, the presence of Mn3O4 in Mn3O4/LSMO reduced the saturation magnetization at T > 50 K (the ferrimagnetic ordering temperature of Mn3O4) but enhanced it at T < 50 K. The decrease of the saturation magnetization in Mn3O4/LSMO for T > 50 K was associated with the appearance and increase of the compressive strain with the increase in Mn3O4 thickness. These observations point to the importance of a ferromagnetic-ferrimagnetic interfacial coupling between the LSMO and Mn3O4 layers in enhancing the surface magnetism of LSMO in the Mn3O4/LSMO bilayers. Our study provides useful information regarding the development of manganite composite thin films with improved magnetic properties for a wide range of technological applications, such as in spintronics and sensor devices.
A new model for optimization of organic light-emitting device by concurrent incorporation of electrical and optical simulations
Authors: Chang Yung-Ting , Liu Shun-Wei , Chen Chin-Ti , Yuan Chih-Hsien , Liu Li-An , Chen Yu-San , Su Wei-Cheng , Lee Kuen-Lin , Wu Chih-I , Lee Chih-Chien
Published: October 2012

To optimize the performance of organic light-emission devices (OLEDs), optical simulation or electrical simulation is often used to help designing the device structures. However, employing electrical or optical simulation separately to optimize the device might lead to incorrect conclusions. A few researches have combined optical and electrical simulations to design OLED structures by merely inserting the maximum carrier recombination rate calculated from electrical simulation into optical simulation programs, which is still insufficient for optimization of OLEDs due to lack of considering the influence of optical interference positions. In this paper, we investigate the OLED performance by using three simulation methods, pure optical, pure electrical, or combination of both, to design the devices. Using the models incorporating both electrical and optical simulations, we found that the optimal emission position occurs neither at the place with the best optical interference nor at the point where carrier recombination rate is the maximum. In order to verify the simulation results, we design the testing devices, red fluorescence OLEDs of bi-layer structures, with various positions of recombination emission. It is found that the position of recombination emission has major impact on the device performance of OLEDs, which lead to some important design rules. With integration of electrical and optical simulations, the real emission position could be predicted with excellent agreements to the experimental results. Applying this method to design the red fluorescent bi-layer OLEDs, the device with very high efficiency of 8.44 cd/A was achieved.
Effects of time and temperature of firing on Fe-rich ceramics studied by Mössbauer spectroscopy and two-dimensional 1H-nuclear magnetic resonance relaxometry
Authors: Casieri Cinzia , De Luca Francesco , Nodari Luca , Russo Umberto , Terenzi Camilla , Tudisca Valentina
Published: October 2012

The combined effects of firing temperature and soaking time on the microstructure of iron-rich porous ceramics have been studied by 57Fe-Mössbauer spectroscopy and 2D 1H nuclear magnetic resonance (NMR) relaxometry using a single-sided probe. Examining water-saturated ceramics using the relaxation correlation method, where longitudinal (T1) and transverse (T2) relaxation times are measured concurrently, provides information about firing-induced changes in both porosity (related to T1) and magnetic properties (related to T2). Comparing the information obtained from 1H-NMR analyses with that obtained from Mössbauer spectroscopy (which characterizes changes in iron-bearing species) shows that the T1-T2 NMR correlation technique is very sensitive to even subtle modifications in the magnetic behavior of Fe-bearing species. Moreover, the single-sided NMR approach allows us to perform millimeter-scale depth-resolved measurements, which can be used to non-invasively study the microstructural heterogeneities associated with non-uniform firing effects inside ceramics. This is in contrast to Mössbauer spectroscopy, which requires that the ceramic samples be ground.
A study of pressure-driven displacement flow of two immiscible liquids using a multiphase lattice Boltzmann approach
Authors: Redapangu Prasanna R. , Chandra Sahu Kirti , Vanka S. P.
Published: October 2012

The pressure-driven displacement of two immiscible fluids in an inclined channel in the presence of viscosity and density gradients is investigated using a multiphase lattice Boltzmann approach. The effects of viscosity ratio, Atwood number, Froude number, capillary number, and channel inclination are investigated through flow structures, front velocities, and fluid displacement rates. Our results indicate that increasing viscosity ratio between the fluids decreases the displacement rate. We observe that increasing the viscosity ratio has a non-monotonic effect on the velocity of the leading front; however, the velocity of the trailing edge decreases with increasing the viscosity ratio. The displacement rate of the thin-layers formed at the later times of the displacement process increases with increasing the angle of inclination because of the increase in the intensity of the interfacial instabilities. Our results also predict the front velocity of the lock-exchange flow of two immiscible fluids in the exchange flow dominated regime. A linear stability analysis has also been conducted in a three-layer system, and the results are consistent with those obtained by our lattice Boltzmann simulations.
High quality factor single-crystal diamond mechanical resonators
Authors: Ovartchaiyapong P. , Pascal L. M. A. , Myers B. A. , Lauria P. , Bleszynski Jayich A. C.
Published: October 2012

Single-crystal diamond is a promising material for microelectromechanical systems (MEMs) because of its low mechanical loss, compatibility with extreme environments, and built-in interface to high-quality spin centers. But its use has been limited by challenges in processing and growth. We demonstrate a wafer bonding-based technique to form diamond on insulator, from which we make single-crystal diamond micromechanical resonators with mechanical quality factors as high as 338 000 at room temperature. Variable temperature measurements down to 10 K reveal a nonmonotonic dependence of quality factor on temperature. These resonators enable integration of single-crystal diamond into MEMs technology for classical and quantum applications.
Single-mode quantum cascade lasers employing asymmetric Mach-Zehnder interferometer type cavities
Authors: Liu Peter Q. , Wang Xiaojun , Gmachl Claire F.
Published: October 2012

We employ properly designed asymmetric Mach-Zehnder interferometer structures as effective wavelength filters and monolithically integrate them in conventional Fabry-Perot cavities to facilitate single-mode operation of the lasers. With such asymmetric Mach-Zehnder interferometer type laser cavities, continuously tunable single-mode operation of quantum cascade (QC) lasers is achieved in pulsed mode from 80 K up to room temperature and in continuous-wave mode with side-mode suppression ratio up to ∼35 dB. These devices are fabricated with the same process as simple ridge lasers, therefore providing a promising solution to achieving more cost-effective single-mode QC lasers.
Scalable control of terahertz radiation from ultrashort laser-gas interaction
Authors: Chen Min , Yuan Xiao-Hui , Sheng Zheng-Ming
Published: October 2012

Terahertz radiation from ultrashort laser pulse interaction with a neutral gas target via ionization induced transverse currents is studied analytically and by particle-in-cell simulations. It is shown that the radiation amplitude and temporal shape depend not only on the driving laser parameters but also on the target parameters both for the forward and backward emissions. For given laser parameters, simply by tuning the gas length and the concentration of the effective ionized electrons, the terahertz temporal shape can be changed in scale with the gas length while keeping the radiation amplitude unchanged. This provides an easy way for terahertz radiation control for applications.
Advances for dielectric elastomer generators: Replacement of high voltage supply by electret
Authors: Jean-Mistral C. , Vu Cong T. , Sylvestre A.
Published: October 2012

Dielectric generators require an external circuit with a high bias voltage source to polarize them. To drastically reduce this circuit and to avoid external polarization, we propose here original transducers combining electrets and dielectric elastomer. Two operating modes have been studied and electromechanical analytical models have been developed from the combination of electrets theory and dielectric model. These concepts are applied on e-textile application: scavenging energy during human motion. An energy density around 6 mJ g−1 is expected on an optimal load of 10 MΩ. More generally, the flexibility, the lightness, the absence of high-voltage supply open many fields of applications beyond e-textiles.
Hand-powered microfluidics: A membrane pump with a patient-to-chip syringe interface
Authors: Gong Max M. , MacDonald Brendan D. , Vu Nguyen Trung , Sinton David
Published: October 2012

In this paper, we present an on-chip hand-powered membrane pump using a robust patient-to-chip syringe interface. This approach enables safe sample collection, sample containment, integrated sharps disposal, high sample volume capacity, and controlled downstream flow with no electrical power requirements. Sample is manually injected into the device via a syringe and needle. The membrane pump inflates upon injection and subsequently deflates, delivering fluid to downstream components in a controlled manner. The device is fabricated from poly(methyl methacrylate) (PMMA) and silicone, using CO2 laser micromachining, with a total material cost of ∼0.20 USD/device. We experimentally demonstrate pump performance for both deionized (DI) water and undiluted, anticoagulated mouse whole blood, and characterize the behavior with reference to a resistor-capacitor electrical circuit analogy. Downstream output of the membrane pump is regulated, and scaled, by connecting multiple pumps in parallel. In contrast to existing on-chip pumping mechanisms that typically have low volume capacity (∼5 μL) and sample volume throughput (∼1–10 μl/min), the membrane pump offers high volume capacity (up to 240 μl) and sample volume throughput (up to 125 μl/min).
Thermodynamic Properties of Ethylene from the Freezing Line to 450 K at Pressures to 260 MPa
Authors: Jahangiri Majid , Jacobsen Richard T , Stewart Richard B. , McCarty Robert D.
Published: October 2012

A new fundamental equation explicit in Helmholtz energy for thermodynamic properties of ethylene from the freezing line to 450 K at pressures to 260 MPa is presented. Independent equations for the vapor pressure for the saturated liquid and vapor densities as functions of temperature, and for the ideal gas heat capacity are also included. The fundamental equation was selected from a comprehensive function of 100 terms on the basis of a statistical analysis of the quality of the fit. The coefficients of the fundamental equation were determined by a weighted least-squares fit to selected P-ρ-T data, saturated liquid, and saturated vapor density data to define the phase equilibrium criteria for coexistence, Cv data, velocity of sound data, and second virial coefficient data. The fundamental equation and the derivative functions for calculating internal energy, enthalpy, entropy, isochoric heat capacity (Cv), isobaric heat capacity (Cp), and velocity of sound are included. Tables of thermodynamic properties of ethylene are given for liquid and vapor states within the range of validity of the fundamental equation. The fundamental equation reported here may generally be used to calculate pressures and densities with an uncertainty of ±0.1%, heat capacities within ±3%, and velocity of sound values within ±1%. Comparisons of calculated properties to experimental data are included to verify the accuracy of the formulation.
Thermodynamic Properties of Nitrogen from the Freezing Line to 2000 K at Pressures to 1000 MPa
Authors: Jacobsen Richard T , Stewart Richard B. , Jahangiri Majid
Published: October 2012

A new fundamental equation explicit in Helmholtz energy for thermodynamic properties of nitrogen from the freezing line to 2000 K at pressures to 1000 MPa is presented. New independent equations for the vapor pressure and for the saturated liquid and vapor densities as functions of temperature are also included. The fundamental equation was selected from a comprehensive function of 100 terms on the basis of a statistical analysis of the quality of the fit. The coefficients of the fundamental equation were determined by a weighted least-squares fit to selected P-ρ-T data, saturated liquid, and saturated vapor density data to define the phase equilibrium criteria for coexistence, and velocity of sound data. The fundamental equation and the derivative functions for calculating internal energy, enthalpy, entropy, isochoric heat capacity (Cv), isobaric heat capacity (Cp), and velocity of sound are included. Tables of thermodynamic properties of nitrogen are given for liquid and vapor states within the range of validity of the fundamental equation. The fundamental equation reported here may generally be used to calculate pressures and densities with an uncertainty of ±0.1%, heat capacities within ±3%, and velocity of sound values within ±1%. Comparisons of calculated properties to experimental data are included to verify the accuracy of the formulation.
Thermodynamic Properties of Twenty-One Monocyclic Hydrocarbons
Authors: Dorofeeva O. V. , Gurvich L. V. , Jorish V. S.
Published: October 2012

The available structural parameters, fundamental frequencies, and relative energies of different stable conformers, if any, for cyclopropane, cyclopropene, cyclobutane, cyclobutene, 1,3-cyclobutadiene, cyclopentane, cyclopentene, 1,3-cyclopentadiene, cyclohexane, cyclohexene, 1,3-cyclohexadiene, 1,4-cyclohexadiene, cycloheptane, cycloheptene, 1,3-cycloheptadiene, 1,3,5-cycloheptatriene, cyclooctane, cyclooctene, 1,3-cyclooctadiene, 1,5-cyclooctadiene, and 1,3,5,7-cyclooctatetraene were critically evaluated and the recommended values selected. Molecular constants for some molecules were estimated as the experimental values for these compounds are not available. This information was utilized to calculate the ideal gas thermodynamic properties C○p, S○, −(G○−H○0)/T, H○−H○0, and log Kf from 100 to 1500 K. The thermal functions were obtained using the rigid-rotor harmonic-oscillator approximation. The contributions derived for the inversion motion of cyclobutane and cyclopentene were obtained from energy levels calculated with the potential functions. For cyclopentane the pseudorotational contributions to thermal functions were calculated by assuming the pseudorotation as the free rotation of the molecule. The calculated values of the thermal functions are compared with those reported in other work. Agreement with experimental data, where such are available, is satisfactory within the experimental uncertainties.
Evaluated Kinetic Data for High-Temperature Reactions. Volume 5. Part 1. Homogeneous Gas Phase Reactions of the Hydroxyl Radical with Alkanes
Authors: Baulch D. L. , Bowers M. , Malcolm D. G. , Tuckerman R. T.
Published: October 2012

The available kinetic data for the homogeneous gas phase reactions of the hydroxyl radical with alkanes have been compiled and critically evaluated. For each reaction, relevant thermodynamic data, a table of measured rate constants, a discussion of the data, and a comprehensive bibliography are presented. Wherever possible the preferred rate parameters are given with their associated error limits and temperature ranges.
Wasting Time? The Differentiation of Travel Time in Urban Transport
Authors: Lin Weiqiang
Published: October 2012

Recent years have seen increasing academic interest in transport and the concept of travel time. In particular, scholars have tried to open up travel time to alternative modes of understanding, taking it beyond its usual productivist associations with waste and useless idleness. The author, however, seeks to understand travel time in a different way. Rather than filling it up with activities, it is argued that travel time must first be recognized as constituted by, and constitutive of, society and its rhythms. As such, the author seeks to unpack its value in context, by thinking through its productions, structuring, and potential effects. With Singapore's urban transport system taken as a case study, the inequitable ways in which travel time is refracted and experienced by different groups of commuters in this fast-paced city are considered. Specifically, how this time has been hastened for some, rescheduled for others, and rendered especially unpredictable for public transit users through various policies and constraints are put into relations. By attending to the unevenness of these differentiated processes, the author argues that a close contextual reading of transport and its manifold rhythms is indispensable if questions surrounding social equity and sustainability are to be adequately addressed.
Dynamics of Spatial Interdependence: The Contingent Effect of International Trade on Voluntary Environmental Standards
Authors: Marcoux Christopher , Urpelainen Johannes
Published: October 2012

Previous research has shown that international trade exposure promotes the diffusion of voluntary environmental standards, such as ISO 14001, from importing nations to exporting nations. However, previous studies have not theorized about the conditions under which trade diffusion is most effective. We argue that international trade exposure influences ISO 14001 adoption rates in countries that have yet to achieve high domestic adoption levels relative to the global average. But if a country achieves a high domestic adoption level, companies have incentives to certify their operations for domestic reasons, and these incentives dominate international influences. Thus, we expect the relative importance of international pressure to decrease as the domestic adoption level increases. International diffusion of ISO 14001, therefore, may not reflect a ‘race to the top’. We test this theory against a global panel dataset on ISO 14001 adoption rates for the years 1995–2007.
Triple Helix Clusters: Boundary Permeability at University—Industry—Government Interfaces as a Regional Innovation Strategy
Authors: Etzkowitz Henry
Published: October 2012

With this paper I discuss the importance of permeability among university—industry—government boundaries based on the experience of MIT and Boston, Stanford and Silicon Valley, the Research Triangle and North Carolina, and Newcastle University and Northeast UK. Encouraging permeability in university boundaries is a first step to creating an entrepreneurial university, the driving force of the most successful innovation regions. Underlying drivers of innovation are transferable and may be instituted by specif c policy initiatives addressing gaps in particular cases. These is no one-size-fits-all ‘best-practice’ mode but there are some common characteristics of innovation regimes such as ‘boundary permeability’ that can be positively influenced by explicit measures.
The Effects of Well Management and the Nature of the Aquifer on Groundwater Resources
Authors: Huang Qiuqiong , Wang Jinxia , Rozelle Scott , Polasky Stephen , Liu Yang
Published: October 2012

We compare groundwater use under collective well management in China, where village leaders allocate water among households, and under private well management where farmers either pump from their own wells or buy water from wells owned by other farmers. Villages are divided into connected or isolated groups depending on whether there are lateral groundwater flows between aquifers underlying a village and neighboring ones. In rural China, households under collective well management use less water. Even under collective management, households located in connected villages use more water, indicating that the connectedness of the aquifers may undermine leaders’ incentives to conserve water.
CDRUG: a web server for predicting anticancer activity of chemical compounds
Authors: Li Gong-Hua , Huang Jing-Fei
Published: October 2012

Summary: Cancer is the leading cause of death worldwide. Screening anticancer candidates from tens of millions of chemical compounds is expensive and time-consuming. A rapid and user-friendly web server, known as CDRUG, is described here to predict the anticancer activity of chemical compounds. In CDRUG, a hybrid score was developed to measure the similarity of different compounds. The performance analysis shows that CDRUG has the area under curve of 0.878, indicating that CDRUG is effective to distinguish active and inactive compounds.

Availability: The CDRUG web server and the standard-alone version are freely available at http://bsb.kiz.ac.cn/CDRUG/.

Contact:  huangjf@mail.kiz.ac.cn

Supplementary information:  Supplementary data are available at Bioinformatics online.
Signal processing with Lévy information
Authors: Brody Dorje C. , Hughston Lane P. , Yang Xun
Published: October 2012

Lévy processes, which have stationary independent increments, are ideal for modelling the various types of noise that can arise in communication channels. If a Lévy process admits exponential moments, then there exists a parametric family of measure changes called Esscher transformations. If the parameter is replaced with an independent random variable, the true value of which represents a ‘message’, then under the transformed measure the original Lévy process takes on the character of an ‘information process’. In this paper we develop a theory of such Lévy information processes. The underlying Lévy process, which we call the fiducial process, represents the ‘noise type’. Each such noise type is capable of carrying a message of a certain specification. A number of examples are worked out in detail, including information processes of the Brownian, Poisson, gamma, variance gamma, negative binomial, inverse Gaussian and normal inverse Gaussian type. Although in general there is no additive decomposition of information into signal and noise, one is led nevertheless for each noise type to a well-defined scheme for signal detection and enhancement relevant to a variety of practical situations.
PhysiomeSpace: digital library service for biomedical data
Authors: Testi Debora , Quadrani Paolo , Viceconti Marco
Published: October 2012

Every research laboratory has a wealth of biomedical data locked up, which, if shared with other experts, could dramatically improve biomedical and healthcare research. With the PhysiomeSpace service, it is now possible with a few clicks to share with selected users biomedical data in an easy, controlled and safe way. The digital library service is managed using a client–server approach. The client application is used to import, fuse and enrich the data information according to the PhysiomeSpace resource ontology and upload/download the data to the library. The server services are hosted on the Biomed Town community portal, where through a web interface, the user can complete the metadata curation and share and/or publish the data resources. A search service capitalizes on the domain ontology and on the enrichment of metadata for each resource, providing a powerful discovery environment. Once the users have found the data resources they are interested in, they can add them to their basket, following a metaphor popular in e-commerce web sites. When all the necessary resources have been selected, the user can download the basket contents into the client application. The digital library service is now in beta and open to the biomedical research community.
Sharing and reusing cardiovascular anatomical models over the Web: a step towards the implementation of the virtual physiological human project
Authors: Gianni Daniele , McKeever Steve , Yu Tommy , Britten Randall , Delingette Hervé , Frangi Alejandro , Hunter Peter , Smith Nicolas
Published: October 2012

Sharing and reusing anatomical models over the Web offers a significant opportunity to progress the investigation of cardiovascular diseases. However, the current sharing methodology suffers from the limitations of static model delivery (i.e. embedding static links to the models within Web pages) and of a disaggregated view of the model metadata produced by publications and cardiac simulations in isolation. In the context of euHeart—a research project targeting the description and representation of cardiovascular models for disease diagnosis and treatment purposes—we aim to overcome the above limitations with the introduction of euHeartDB, a Web-enabled database for anatomical models of the heart. The database implements a dynamic sharing methodology by managing data access and by tracing all applications. In addition to this, euHeartDB establishes a knowledge link with the physiome model repository by linking geometries to CellML models embedded in the simulation of cardiac behaviour. Furthermore, euHeartDB uses the exFormat—a preliminary version of the interoperable FieldML data format—to effectively promote reuse of anatomical models, and currently incorporates Continuum Mechanics, Image Analysis, Signal Processing and System Identification Graphical User Interface (CMGUI), a rendering engine, to provide three-dimensional graphical views of the models populating the database. Currently, euHeartDB stores 11 cardiac geometries developed within the euHeart project consortium.
Arrhythmic risk biomarkers for the assessment of drug cardiotoxicity: from experiments to computer simulations
Authors: Corrias A. , Jie X. , Romero L. , Bishop M. J. , Bernabeu M. , Pueyo E. , Rodriguez B.
Published: October 2012

In this paper, we illustrate how advanced computational modelling and simulation can be used to investigate drug-induced effects on cardiac electrophysiology and on specific biomarkers of pro-arrhythmic risk. To do so, we first perform a thorough literature review of proposed arrhythmic risk biomarkers from the ionic to the electrocardiogram levels. The review highlights the variety of proposed biomarkers, the complexity of the mechanisms of drug-induced pro-arrhythmia and the existence of significant animal species differences in drug-induced effects on cardiac electrophysiology. Predicting drug-induced pro-arrhythmic risk solely using experiments is challenging both preclinically and clinically, as attested by the rise in the cost of releasing new compounds to the market. Computational modelling and simulation has significantly contributed to the understanding of cardiac electrophysiology and arrhythmias over the last 40 years. In the second part of this paper, we illustrate how state-of-the-art open source computational modelling and simulation tools can be used to simulate multi-scale effects of drug-induced ion channel block in ventricular electrophysiology at the cellular, tissue and whole ventricular levels for different animal species. We believe that the use of computational modelling and simulation in combination with experimental techniques could be a powerful tool for the assessment of drug safety pharmacology.
Toward integrated management of cerebral aneurysms
Authors: Villa-Uriol M. C. , Larrabide I. , Pozo J. M. , Kim M. , Camara O. , De Craene M. , Zhang C. , Geers A. J. , Morales H. , Bogunović H. , Cardenes R. , Frangi A. F.
Published: October 2012

In the last few years, some of the visionary concepts behind the virtual physiological human began to be demonstrated on various clinical domains, showing great promise for improving healthcare management. In the current work, we provide an overview of image- and biomechanics-based techniques that, when put together, provide a patient-specific pipeline for the management of intracranial aneurysms. The derivation and subsequent integration of morphological, morphodynamic, haemodynamic and structural analyses allow us to extract patient-specific models and information from which diagnostic and prognostic descriptors can be obtained. Linking such new indices with relevant clinical events should bring new insights into the processes behind aneurysm genesis, growth and rupture. The development of techniques for modelling endovascular devices such as stents and coils allows the evaluation of alternative treatment scenarios before the intervention takes place and could also contribute to the understanding and improved design of more effective devices. A key element to facilitate the clinical take-up of all these developments is their comprehensive validation. Although a number of previously published results have shown the accuracy and robustness of individual components, further efforts should be directed to demonstrate the diagnostic and prognostic efficacy of these advanced tools through large-scale clinical trials.