bluuebunny/crossref_metadata_2025 huggingface dataset:
Characterization of a novel large-field cone bipolar cell type in the primate retina: Evidence for selective cone connections
Authors: JOO HANNAH R. , PETERSON BETH B. , HAUN TONI J. , DACEY DENNIS M.
Published: December 2010

Parallel processing of visual information begins at the first synapse in the retina between the photoreceptors and bipolar cells. Ten bipolar cell types have been previously described in the primate retina: one rod and nine cone bipolar types. In this paper, we describe an 11th type of bipolar cell identified in Golgi-stained macaque retinal whole mount and vertical section. Axonal stratification depth, in addition to dendritic and axonal morphology, distinguished the “giant” cell from all previously well-recognized bipolar cell types. The giant bipolar cell had a very large and sparsely branched dendritic tree and a relatively large axonal arbor that costratified with the DB4 bipolar cell near the center of the inner plexiform layer. The sparseness of the giant bipolar’s dendritic arbor indicates that, like the blue cone bipolar, it does not contact all the cones in its dendritic field. Giant cells contacting the same cones as midget bipolar cells, which are known to contact single long-wavelength (L) or medium-wavelength (M) cones, demonstrate that the giant cell does not exclusively contact short-wavelength (S) cones and, therefore, is not a variant of the previously described blue cone bipolar. This conclusion is further supported by measurement of the cone contact spacing for the giant bipolar. The giant cell contacts an average of about half the cones in its dendritic field (mean ± s.d. = 52 ± 17.6%; n = 6), with a range of 27–82%. The dendrites from single or neighboring giant cells that converge onto the same cones suggest that the giant cell may selectively target a subset of cones with a highly variable local density, such as the L or M cones.
EDWIN WALTER KEMMERER AND THE ORIGINS OF THE FED
Authors: GOMEZ BETANCOURT REBECA
Published: December 2010

In this article we analyze Edwin Walter Kemmerer’s contribution to the creation of the Federal Reserve System. Firstly, we contrast Kemmerer’s role in the transition from the Aldrich banking reform plan to the Glass–Owen plan with those of A. Piatt Andrew (who was Aldrich’s main advisor), H. Parker Willis (i.e., Carter Glass’s advisor), and J.L. Laughlin (who was Willis’ mentor). Secondly, we deal with theoretical questions posed by Kemmerer, who, as we assert, developed his own banking reform plan. Even if his proposals were not immediately taken into account in theFederal Reserve Actof 1913, he contributes to the institutional structure of the Federal Reserve System.
A NOTE ON THE IMPACT OF PROGRESSIVE DIVIDEND TAXATION ON INVESTMENT DECISIONS
Authors: Santoro Marika , Wei Chao
Published: December 2010

This paper studies the distortionary impact of progressive dividend taxation on investment decisions under the premises of the “new” view. According to the new view, proportional dividend taxation does not distort firms' investment decisions. We find that progressive dividend taxation distorts investment decisions due to endogenous variations in the marginal tax rate caused by stochastic taxable income over the business cycle. The magnitude of this distortion critically depends upon the marginal tax rate and the progressivity of the tax system.
COIN SIZES AND PAYMENTS IN COMMODITY MONEY SYSTEMS
Authors: Redish Angela , Weber Warren E.
Published: December 2010

Contemporaries and economic historians have noted several features of medieval and early modern European monetary systems that are hard to analyze using models of centralized exchange. For example, contemporaries complained of recurrent shortages of small change and argued that an abundance/dearth of money had real effects on exchange, especially for the poor. To confront these facts, we build a random-matching monetary model with two indivisible coins with different intrinsic values. The model shows that small change shortages can exist, in the sense that adding small coins to an economy with only large coins is welfare-improving. This effect is amplified by increases in trading opportunities. Further, changes in the quantity of monetary metals affect the real economy and the amount of exchange as well as the optimal denomination size. Finally, the model shows that replacing full-bodied small coins with tokens is not necessarily welfare-improving.
Survey and alignment design for the Taiwan photon source
Authors: Lai W.-Y. , Lin C. J. , Ho H. C. , Tseng T. C. , Perng S. Y. , Wang H. S. , Hsu K. H. , Tsai Y. L. , Syu J. C. , Chen M. L. , Chen J. R.
Published: December 2010

Taiwan Photon Source is a new 3-GeV ring with characteristics of great brightness and small emittance, at present under construction at National Synchrotron Radiation Research Center (NSRRC) site in Taiwan and due to be commissioned in 2013. The positioning of the magnets is highly sensitive to alignment errors, and the entire building will be constructed half underground at depth 12 m relative to Taiwan Light Source (TLS) for stability reasons; for these reasons the survey and alignment work is confined and difficult. To position magnets precisely and quickly, a highly accurate auto-tuning girder system combined with a survey network was designed to accomplish the alignment tasks. The survey network includes a preliminary Global Positioning System (GPS) network and a laser-tracking network. The position data from the survey network define a basis for the system of motorized girders to auto-tune and improve the accuracy. The detailed survey and alignment design, simulation and preliminary data are described in this paper.
Design of a fast rotational chopper for X-ray pump–probe experiments at Diamond Light Source
Authors: Varandas Luis , Peach Andrew , Collins Kevin , Nutter Brian
Published: December 2010

New trends in X-ray crystallography are concerned with the study of transient conditions of atomic structures, which take place after an energy activation agent is introduced. These time-resolved experiments require a fast mechanical shutter to interrupt the X-ray beam in a pump–probe cycle, with the aim to generate a stroboscopic effect. Thus, only diffraction data that are representative of the activated structure are actually collected. A rotating type of shutter, also known as chopper, is presented with the purpose to enable time-resolved experiments to be performed at I19 small-molecule single-crystal diffraction beamline. Exceptional stability in the rotational speed is critical to achieve the desired stroboscopic effect with minimum jitter. This requirement can be addressed only through design by the specification of suitable components and implementation of high-precision methods in manufacturing. The proposed equipment is comprised of a spindle supported on air bearings coupled to a slotted disc rotating inside a vacuum enclosure and driven by a brushless servo motor. Advanced control features are proposed to ensure that speed stability is achieved. Preliminary tests produced very encouraging results, giving strong indication that the chopper satisfies the specifications required for time-resolved experiments.
Measurement and characterization of precision rotary axes at the European Synchrotron Radiation Facility
Authors: Nicola M. , van der Kleij H. P.
Published: December 2010

For some beamlines, where the X-ray beam is focussed to less than 100 nm spot size, it is necessary to rotate the sample using very accurate rotary axes. The accuracy of these devices is defined in terms of radial, axial and tilt errors. At the Precision Engineering Laboratory of the ESRF, we are able to calibrate rotary stages and spindles in agreement with the ISO 230-7 and ASME B89.3.4 standards, in static mode (step by step, at given position increments) or in continuous motion. This type of measurement is possible through the use of non-contact capacitive sensors (with measuring resolution in the field of the nanometre) and reference spherical artefacts, working under controlled environmental conditions to minimize the influence of thermal instabilities. The setup includes a special granite stage with a gantry, supported by an active anti-vibration system. The presentation will illustrate the measurement principle and some examples of calibrations, including results obtained on a motorized air-bearing rotary stage for which the measured errors are about 20 nm.
Mechanical design of a dual-cryostat instrument for a high-field pulsed magnet
Authors: Capatina D. , Islam Z. , Trakhtenberg E. , Nojiri H. , Narumi Y.
Published: December 2010

The engineering of a dual-cryostat for a pulsed-magnet instrument at the Advanced Photon Source is presented. The dual-cryostat independently cools the magnet coil (using liquid-nitrogen) and the sample (using a closed-cycle refrigerator). Liquid-nitrogen cooling may allow a repetition rate of a few minutes for peak fields near 30 T. The system is unique in that the liquid-nitrogen cryostat incorporates a double-funnel vacuum tube passing through the solenoid's bore in order to preserve the entire angular range allowed by the magnet bore for scattering studies. Second, the use of a separate refrigerator for the sample allows precise positioning of samples in the bore while minimizing magnet vibrations propagating to the sample during pulsed-field generation.
Three grating monochromator for the vacuum-ultraviolet radiation beamline at the Swiss Light Source
Authors: Ellenberger U. , Kalt H. , Böhler P. , Schwarb A. , Sonderegger S. , Keller A. , Maag S. , Gerber T.
Published: December 2010

The beamline optics of the vacuum-ultraviolet radiation beamline installed on a bending magnet of the Swiss Light Source are to be upgraded. Supports for all three optical elements of the beamline optics (collimating mirror, plane grating monochromator and focusing mirror) have been re-designed to allow a more stable and improved fine tuning. The monochromator is composed of a set of three interchangeable gratings mounted on a rotatable platform. Each grating is framed in an optimized goniometer mount, designed and built in-house, which uses flexible elements for precise and reproducible adjustments. The roll and yaw of the gratings can be adjusted with microradian precision to minimize conical diffraction.
ALBA XALOC beamline diffractometer table skin concept design
Authors: Colldelram C. , Ruget C. , Nikitina L.
Published: December 2010

The XALOC beamline is dedicated to macromolecular crystallography. The position and angle of the X-ray beam at the sample change in horizontal and vertical directions. Consequently, the support of the sample has to follow the beam with two linear and two rotational movements. For this purpose ALBA engineering division has developed a positioning table in house. The main goal of the design was to achieve high resolution, accuracy and stability. Effective resolution and accuracy need adequate actuators and high stability, in the range of 0.1 µm and 0.2 µrad resolution and 1 µm repeatability and first resonance mode f0 = 45 Hz (static and dynamic), for a 1.5 m-long, 1 m-high and 0.6 m-wide table which can support 0.5 tonnes of payload. The actuators were chosen by analytical calculations, whereas the stability is accomplished by a design that minimizes the thermal drifts and avoids the amplification of the vibrations from the ground, increasing the frequency of the resonance modes. The concept is based on a big block of natural granite that acts as a very stable reference base, in terms of thermal expansion and stiffness, and the mechanics are placed as close as possible to this reference. In this manner, the thermal drift is minimized and the stiffness is maximized. Conceptually, the mechanics can be imagined as a skin around the granite base. To reach a proper design several solutions have been analysed, with Finite element analysis (FEA) tools, to validate a compromise solution which has been produced and tested.
Chronische Pankreatitis
Authors: Vogt
Published: December 2010

Die chronische Pankreatitis ist charakterisiert durch rezidivierende Schmerzepisoden. Im Verlauf der Erkrankung entwickeln sich eine exokrine und endokrine Insuffizienz. Als wesentliche Komplikationen können Pankreaspseudozysten und ein Pankreaskarzinom auftreten. Hauptursache der chronischen Pankreatitis ist ein meist ausgeprägter chronischer Alkoholkonsum. Doch auch kleine Mengen Alkohol können bereits ausreichend sein. Die Schmerzbehandlung umfasst neben der absoluten Alkoholkarenz die medikamentöse Schmerztherapie sowie endoskopisch-interventionelle und chirurgische Therapie.
Update FAST
Authors: Osterwalder
Published: December 2010

Die FAST-Untersuchung ist seit vielen Jahren ein diagnostisches Standardverfahren in der Traumatologie. Bis vor kurzem wurde sie von den deutschsprachigen Ultraschallgesellschaften nicht anerkannt und fehlt deshalb im aktuellen Ausbildungsangebot. Das Akronym «FAST» bedeutet «Focused Assessment with Sonography for Trauma» und wird definiert als sonographische Suche nach intraperitonealer, pleuraler und perikardialer Flüssigkeit bei Patienten mit stumpfem oder penetrierendem Trauma. Die Erweiterung zum eFAST («extended FAST») im Jahre 2004 mit zusätzlicher Diagnostik des Pneumothorax war nur der Beginn einer rasanten weiteren Entwicklung. So spricht man heute bereits von FAST-plus und meint damit eine Vielzahl von Anwendungen im Rahmen des Atemwegsmanagements, der Diagnostik von Organverletzungen, des Hirnhochdrucks sowie als Unterstützung bei invasiven Verfahren. Wohin FAST geht, hängt jedoch von der Rolle ab, welche die Computertomographie (CT) in Zukunft einnehmen wird. Es ist nämlich noch offen, ob die CT im Sinne von FACTT («Focused Assessment with Computer-Tomography in Trauma») das FAST verdrängen und zum Standarddiagnostikum avancieren kann.
Kinetics of superoxide reactions with dissolved organic matter in tropical Atlantic surface waters near Cape Verde (TENATSO)
Authors: Heller M. I. , Croot P. L.
Published: December 2010

The decay kinetics of superoxide (O2−) reacting with organic matter was examined in oligotrophic waters at, and nearby, the TENATSO ocean observatory adjacent to the Cape Verde archipelago. Superoxide is the short‐lived primary photochemical product of colored dissolved organic matter (CDOM) photolysis and also reacts with CDOM or trace metals (Cu, Fe) to form H2O2. In the present work we focused our investigations on reactions between CDOM and superoxide. O2− decay kinetics experiments were performed by adding KO2 to diethylenetriaminepentaacetic acid (DTPA) amended seawater and utilizing an established chemiluminescence technique for the detection of O2− at nM levels. In Cape Verdean waters we found a significant reactivity of superoxide with CDOM with maximal rates adjacent to the chlorophyll maximum, presumably from production of new CDOM from bacteria/phytoplankton. This work highlights a poorly understood process which impacts on the biogeochemical cycling of CDOM and trace metals in the open ocean.
The 2006 slow slip event and nonvolcanic tremor in the Mexican subduction zone
Authors: Kostoglodov Vladimir , Husker Allen , Shapiro Nikolai M. , Payero Juan S. , Campillo Michel , Cotte Nathalie , Clayton Robert
Published: December 2010

The last decade featured an explosive sequence of discoveries of slow slip events (SSE) and nonvolcanic tremor (NVT) in different subduction zones and continental faults. Many observations show that SSE is usually associated with an increased NVT activity but it is not clear yet if those events are the result of the same process or are independent expressions of a common underlying seismotectonic source. A large SSE in Central Mexico occurred in 2006 during the Meso‐American Subduction Experiment (MASE) which provided continuous observations of the NVT for the years 2005–2007. GPS and abundant seismic data show that although the NVT energy increased notably during the 2006 SSE, the two phenomena were separated spatially and not completely synchronized in time. Significant NVT episodes occur during the period between SSEs, suggesting again that large slow slip events and NVT observed in the Mexican subduction zone are of different origins. The results presented here contribute to uncovering the nature of these two separate phenomena that have been indistinguishable in some other regions.
Global magnetohydrodynamic simulation of reconnection and turbulence in the plasma sheet
Authors: El‐Alaoui Mostafa , Ashour‐Abdalla Maha , Richard Robert L. , Goldstein Melvyn L. , Weygand James M. , Walker Raymond J.
Published: December 2010

Plasma sheet turbulence is examined by using a global MHD simulation. The simulation used idealized purely southward interplanetary magnetic field (IMF) driving conditions to eliminate the effect of solar wind and IMF variations. The results were compared with spacecraft observations of turbulence by computing power spectral densities and probability distribution functions. The fluctuations in the simulation were found to have properties characteristic of turbulence. The MHD simulation exhibited nested vortices on multiple scales, with the largest scales associated with reconnection outflows and the diversion of high‐speed flows in the near‐Earth region. The importance of strong localized reconnection regions in the simulation for driving the largest scale fluctuations supports the idea it is the main process driving turbulence in the plasma sheet. Interplay between turbulence and the reconnection process is probably present. Scaling arguments show that the scale at which turbulence is dissipated is consistent with the resistivity in the model.
Variations of the global lightning distribution revealed from three‐station Schumann resonance measurements
Authors: Shvets A. V. , Hobara Y. , Hayakawa M.
Published: December 2010

Schumann resonance (SR) observations performed simultaneously by a global network consisting of three stations (Lekhta (Karelia, Russia), Moshiri (Hokkaido, Japan), and West Greenwich (Rhode Island, United States)) during almost 1 year were used for mapping world thunderstorm activity. A two‐stage inverse problem is solved for locating lightning sources distributed over the Earth's surface from the SR background signals. The first stage consists of inversions of the SR magnetic field power spectra to the distributions of lightning intensity by distance relative to an observation point. The obtained distance profiles of intensity of sources are used as tomographic projections for reconstructing a spatial distribution of sources in the second stage. We have suggested the use of source distance profiles obtained from the spectra of outputs of two orthogonal magnetic antennas operating at each observatory as separate tomographic projections. It is shown that the implementation of additional information on the azimuthal distribution of sources, provided by angular selectivity of magnetic sensors, significantly improves the quality of global lightning mapping under the condition of a limited number of observation stations. Maps of the global lightning distributions constructed by the result of inversions of SR spectra show that the most active regions vary zonally on the seasonal time scale and meridionally on the diurnal time scale being connected mainly with continental areas in the tropics.
An analysis of pump‐induced artificial ionospheric ion upwelling at EISCAT
Authors: Kosch M. J. , Ogawa Y. , Rietveld M. T. , Nozawa S. , Fujii R.
Published: December 2010

Ion outflow from the high‐latitude ionosphere is a well‐known phenomenon and an important source of plasma for the magnetosphere. It is also well known that pumping the ionosphere with high‐power high‐frequency radio waves causes electron heating. On a few occasions, this has been accompanied by artificially induced ion upwelling. We analyze such a controlled experiment at EISCAT up to 600 km altitude. The pump‐enhanced electron temperatures reached up to ∼4000 K above 350 km, and ion upwelling reached up to ∼300 m/s above 500 km altitude. The pump‐induced electron pressure gradient can explain the ion velocity below 450 km. Between 450 and 600 km the electron pressure gradient correlates equally with ion acceleration and ion velocity, which represents the transition altitude to free ion acceleration. The electron gas pressure gradient can explain ion upwelling, at least up to 600 km altitude. In addition, such active experiments open the possibility to estimating the F layer ion‐neutral collision frequency and neutral density with altitude from ground‐based observations.
Nocturnal convective cloud formation under clear‐sky conditions at the eastern Andes of south Ecuador
Authors: Trachte K. , Rollenbeck R. , Bendix J.
Published: December 2010

The formation of nocturnal convective clouds at the eastern Andes of south Ecuador and the adjacent Peruvian Amazon basin was investigated in a numerical model study. Their formation is expected to be an interactive procedure of nocturnal downslope flows in the Andean terrain, which forms a concave drainage system in the target area. Satellite imagery were used for both the identification of a sample case with a nocturnal cold cloud appearance and for the verification of the simulated results. The cloud patterns were distinguished on the basis of IR temperatures. A comparison of the data demonstrated the occurrence of a cold cloud shield in the target area, although the modeled cluster is significantly smaller. Further analysis of the development of the convective cells confirmed the assumed underlying processes. A strong current in the lower atmosphere, presumably a drainage flow, was recognizable in association with strong moisture convergence using a cross section through the cluster. Their presence was confirmed on the basis of their characteristic features and the surface energy fluxes as the driving force for thermally induced downslope flows.
Observational characteristics of the tropopause inversion layer derived from CHAMP/GRACE radio occultations and MOZAIC aircraft data
Authors: Schmidt T. , Cammas J.‐P. , Smit H. G. J. , Heise S. , Wickert J. , Haser A.
Published: December 2010

In this study we discuss characteristics of the Northern Hemisphere (NH) midlatitude (40°N–60°N) tropopause inversion layer (TIL) based on two data sets. First, temperature measurements from GPS radio occultation data (CHAMP and GRACE) for the time interval 2001–2009 are used to exhibit seasonal properties of the TIL bottom height defined here as the height of the squared buoyancy frequency minimum N2 below the thermal tropopause, the TIL maximum height as the height of the N2 maximum above the tropopause, and the TIL top height as the height of the temperature maximum above the tropopause. Mean values of the TIL bottom, TIL maximum, and TIL top heights relative to the thermal tropopause for the NH midlatitudes are (−2.08 ± 0.35) km, (0.52 ± 0.10) km and (2.10 ± 0.23) km, respectively. A seasonal cycle of the TIL bottom and TIL top height is observed with values closer to the thermal tropopause during summer. Secondly, high‐resolution temperature and trace gas profile measurements on board commercial aircrafts (Measurement of Ozone and Water Vapor by Airbus In‐Service Aircraft (MOZAIC) program) from 2001–2008 for the NH midlatitude (40°N–60°N) region are used to characterize the TIL as a mixing layer around the tropopause. Mean TIL bottom, TIL maximum, and TIL top heights based on the MOZAIC temperature (N2) measurements confirm the results from the GPS data, even though most of the MOZAIC profiles used here are available under cyclonic situations. Further, we demonstrate that the mixing ratio gradients of ozone (O3) and carbon monoxide (CO) are suitable parameters for characterizing the TIL structure.
Combinational Therapy Using Hypothermia and the Immunophilin Ligand FK506 to Target Altered Pial Arteriolar Reactivity, Axonal Damage, and Blood–Brain Barrier Dysfunction after Traumatic Brain Injury in Rat
Authors: Oda Yasutaka , Gao Guoyi , Wei Enoch P , Povlishock John T
Published: December 2010

This study evaluated the utility of combinational therapy, coupling delayed posttraumatic hypothermia with delayed FK506 administration, on altered cerebral vascular reactivity, axonal injury, and blood–brain barrier (BBB) disruption seen following traumatic brain injury (TBI). Animals were injured, subjected to various combinations of hypothermic/FK506 intervention, and equipped with cranial windows to assess pial vascular reactivity to acetylcholine. Animals were then processed with antibodies to the amyloid precursor protein and immunoglobulin G to assess axonal injury and BBB disruption, respectively. Animals were assigned to five groups: (1) sham injury plus delayed FK506, (2) TBI, (3) TBI plus delayed hypothermia, (4) TBI plus delayed FK506, and (5) TBI plus delayed hypothermia with FK506. Sham injury plus FK506 had no impact on vascular reactivity, axonal injury, or BBB disruption. Traumatic brain injury induced dramatic axonal injury and altered pial vascular reactivity, while triggering local BBB disruption. Delayed hypothermia or FK506 after TBI provided limited protection. However, TBI with combinational therapy achieved significantly enhanced vascular and axonal protection, with no BBB protection. This study shows the benefits of combinational therapy, using posttraumatic hypothermia with FK506 to attenuate important features of TBI. This suggests that hypothermia not only protects but also extends the therapeutic window for improved FK506 efficacy.
Hyperglycaemia and Infarct Size in Animal Models of Middle Cerebral Artery Occlusion: Systematic Review and Meta-Analysis
Authors: MacDougall Niall J J , Muir Keith W
Published: December 2010

Poststroke hyperglycaemia (PSH) is common, has an unclear pathophysiology, and is associated with poor outcomes. Animal studies report conflicting findings. We systematically reviewed the effects of hyperglycaemia on infarct volume in middle cerebral artery occlusion (MCAO) models, generating weighted mean differences between groups using random effects models summarised as effect size (normalised to control group infarct volume as 100%) and 95% confidence interval. Of 72 relevant papers, 23 reported infarct volume. Studies involved 664 animals and 35 distinct comparisons. Hyperglycaemia was induced by either streptozotocin (STZ, 17 comparisons, n=303) or dextrose (18 comparisons, n=356). Hyperglycaemic animals had infarcts that were 94% larger, but STZ was associated with significantly greater increase in infarct volumes than dextrose infusion (140% larger versus 48% larger). In seven studies, insulin did not significantly reduce infarct size and results were heterogeneous. Although hyperglycaemia exacerbates infarct volume in MCAO models, studies are heterogeneous, and do not address the common clinical problem of PSH because they have used either the STZ model of type I diabetes or extremely high glucose loads. Insulin had a nonsignificant and significantly heterogeneous effect. Further studies with relevant models may inform clinical trial design.
Development of a new photoelectron spectroscopy instrument combining an electrospray ion source and photoelectron imaging
Authors: McKay A. R. , Sanz M. E. , Mooney C. R. S. , Minns R. S. , Gill E. M. , Fielding H. H.
Published: December 2010

A new apparatus has been constructed that combines electrospray ionization with a quadrupole mass filter, hexapole ion trap, and velocity-map imaging. The purpose is to record photoelectron images of isolated chromophore anions. To demonstrate the capability of our instrument we have recorded the photodetachment spectra of isolated deprotonated phenol and indole anions. To our knowledge, this is the first time that the photodetachment energy of the deprotonated indole anion has been recorded.
Slow dynamics of a colloidal lamellar phase
Authors: Constantin Doru , Davidson Patrick , Freyssingeas Éric , Madsen Anders
Published: December 2010

We used x-ray photon correlation spectroscopy to study the dynamics in the lamellar phase of a platelet suspension as a function of the particle concentration. We measured the collective diffusion coefficient along the director of the phase, over length scales down to the interparticle distance, and quantified the hydrodynamic interaction between the particles. This interaction sets in with increasing concentration and can be described qualitatively by a simplified model. No change in the microscopic structure or dynamics is observed at the transition between the fluid and the gel-like lamellar phases.
Scalable free energy calculation of proteins via multiscale essential sampling
Authors: Moritsugu Kei , Terada Tohru , Kidera Akinori
Published: December 2010

A multiscale simulation method, “multiscale essential sampling (MSES),” is proposed for calculating free energy surface of proteins in a sizable dimensional space with good scalability. In MSES, the configurational sampling of a full-dimensional model is enhanced by coupling with the accelerated dynamics of the essential degrees of freedom. Applying the Hamiltonian exchange method to MSES can remove the biasing potential from the coupling term, deriving the free energy surface of the essential degrees of freedom. The form of the coupling term ensures good scalability in the Hamiltonian exchange. As a test application, the free energy surface of the folding process of a miniprotein, chignolin, was calculated in the continuum solvent model. Results agreed with the free energy surface derived from the multicanonical simulation. Significantly improved scalability with the MSES method was clearly shown in the free energy calculation of chignolin in explicit solvent, which was achieved without increasing the number of replicas in the Hamiltonian exchange.
Pattern formation and propagation during microwave breakdown
Authors: Chaudhury Bhaskar , Boeuf Jean-Pierre , Zhu Guo Qiang
Published: December 2010

During microwave breakdown at atmospheric pressure, a sharp plasma front forms and propagates toward the microwave source at high velocities. Experiments show that the plasma front may exhibit a complex dynamical structure or pattern composed of plasma filaments aligned with the wave electric field and apparently moving toward the source. In this paper, we present a model of the pattern formation and propagation under conditions close to recent experiments. Maxwell’s equations are solved together with plasma fluid equations in two dimensions to describe the space and time evolution of the wave field and plasma density. The simulation results are in excellent agreement with the experimental observations. The model provides a physical interpretation of the pattern formation and dynamics in terms of ionization-diffusion and absorption-reflection mechanisms. The simulations allow a good qualitative and quantitative understanding of different features such as plasma front velocity, spacing between filaments, maximum plasma density in the filaments, and influence of the discharge parameters on the development of well-defined filamentary plasma arrays or more diffuse plasma fronts.
Electric field assisted manipulation of microdroplets on a superhydrophobic surface
Authors: Shi L. T. , Jiang C. G. , Ma G. J. , Wu C. W.
Published: December 2010

The efficient manipulation of low-volume droplets offers many potential applications in relation to chemical and biomedical tests and protocols. A novel approach to the manipulation of a microdroplet on a superhydrophobic surface is introduced in the present communication. The microdroplet was first picked up onto a hydrophilic needle, transported from one location to another, and finally released under the action of an electric field force. Three key parameters in this process, the radius of the droplet, the distance between the two electrodes, and the required voltage, were investigated. This study should be helpful for the design of microfluidic devices.
Defect-related room-temperature ferroelectricity in tensile-strained SrTiO3 thin films on GdScO3 (110) substrates
Authors: Kim Yong Su , Choi J. S. , Kim J. , Moon S. J. , Park B. H. , Yu J. , Kwon J.-H. , Kim M. , Chung J.-S. , Noh T. W. , Yoon J.-G.
Published: December 2010

We investigate room-temperature (RT) ferroelectricity in tensile-strained SrTiO3 (STO) thin films grown on GdScO3 (110) substrates. To separate the strain and the defect dipole effect, we apply an electric field to measure the polarization in the direction perpendicular to the elongation axis, and the RT ferroelectric polarization is found to be perpendicular to that axis. These results clearly demonstrate the importance of the contribution of defect dipoles to the RT ferroelectricity observed in STO thin films.
Purchaser – Provider Split: Does Theory Match Evidence in Tasmania?
Authors: Mohammed Abdulai K
Published: December 2010

I examine the purchaser – provider split in the contexts of two local government areas (Hobart and Sorell) in Tasmania, Australia. I assess whether that split has delivered on the promised effects. I also examine the influence that context has on response outcomes to the purchaser – provider arrangement. Specifically, I pay attention to the impact of purchaser – provider reform on service spending, aggregate municipal spending, and total employment. The evidence shows that the use of the purchaser – provider split is viable only for large programme expenditures. The purchaser – provider split is not related to total municipal spending even though it may be negatively related to the programmes that are subject to it. Savings from purchaser – provider reform result in increased spending and therefore employment elsewhere in the local authority. Greater efficiency gains in some jurisdictions are attributable more to particular local favourable contextual conditions than to the purchaser – provider split per se.
International Urban Festivals as a Catalyst for Governance Capacity Building
Authors: Benneworth Paul , Dauncey Hugh
Published: December 2010

The capacity-building benefits for urban governance of unsuccessfully bidding for large events are often asserted, but much more rarely demonstrated. With the cost of bidding for an Olympics now running at US $25 million, we seek to address this gulf by asking whether the trend for ‘festivalisation’ amongst urban managers is rationally underpinned. Drawing on Lyon's bid for the 1968 Summer Games, we look at the role played—materially, politically, and symbolically—by the Olympics bidding process, and its influence on Lyon's later trajectory. The Lyon bid put forward proposals for its position within a pan-European urban hierarchy which have become influential in European spatial planning. Yet, this situation is not a consequence solely of the Olympics bid, but also of a critical urban governance moment in which the bid played a complicated role. By reflecting on the dimensions of influence within which the bidding process became involved we seek to provide a greater depth to the way that international festivals are regarded in contemporary conceptualistions of metropolitan development and governance.
The Changing Role of the State in Dutch Regional Partnerships
Authors: Kuindersma Wiebren , Boonstra Froukje G
Published: December 2010

We address the changing relationship of the state vis-à-vis regional partnerships on issues of state policy performance, partnership legitimacy, and the role and position of the state. Theoretical expectations regarding these issues differ greatly according to whether a state-centric or a society-centric perspective is adopted. A general case study of Dutch area-based rural policy (1988–2008) reveals that changes predominantly lean towards the state-centric perspective. These changes include an increased usage of regional partnerships as state instruments, an improved democratic anchorage of regional partnerships, and a continuation of the state's privileged position. An embedded case study shows that individual partnerships can continue to develop in other directions and can institutionalise into largely self-organising partnerships. We conclude by showing that regional partnerships can serve as state instruments, provided that a certain degree of self-organisation is possible. Overregulation of regional partnerships could eventually undermine their overall performance.
Current and future issues facing red meat quality in a competitive market and how to manage continuous improvement
Authors: Pethick D. W. , Ball A. J. , Banks R. G. , Hocquette J. F.
Published: December 2010

This paper discusses current and future issues facing lamb and beef meat quality and proposes strategies to manage quality improvements into the future. Based on survey data of Australian consumers and whole supply chain profit drivers, it is argued that the three most important quality areas for future research are lean meat yield, eating quality and human nutritive value. These areas have complex biological interactions, both antagonistic and complimentary, which require careful management so as to produce the best outcome for industry and the consumer. It is argued that the best way forward is to undertake collaborative research that encompasses industry production, meat science and genetics simultaneously. The case study of the Australian lamb industry is used as a suggested model for future progression, whereby a large breeding program forms the central focus of numerous research and delivery activities. Another issue raised is the need for strong and cost-effective industry systems that are able to effectively utilise outcomes from genetics, lean meat yield and eating quality to deliver the research results.
Future research priorities for animal production in a changing world
Authors: Scollan N. D. , Greenwood P. L. , Newbold C. J. , Ruiz D. R. Yáñez , Shingfield K. J. , Wallace R. J. , Hocquette J. F.
Published: December 2010

This paper reports the outcomes from an International Workshop on ‘Animal Production in a Changing World’ held in Clermont-Ferrand (INRA-Theix, France) on 9–10 September 2009 in which 35 participants from 15 different countries participated. The main objective was to discuss the main challenges within the livestock sector: its environmental impact and role in global climate change; balancing the need for increased production of animal products coupled with a lower footprint and addressing societal needs in terms of product quality for the consumer. Five key lectures presented the main drivers of animal agriculture: population growth, environmental impact, mitigation and adaptation options, efficiency of production and quality of animal products. The key lectures highlighted the synergies between research needs and strategies dedicated to improving food quality and safety and those devoted to decreasing the environmental impact of ruminant livestock production. After the lectures two discussion groups were set up to discuss the main research priorities in relation to reducing environmental footprint and improving product quality. The main remarks from the group working on product quality were that the existing knowledge is not fully applied, the priorities with regards to quality differ between developing and developed countries and that, as one component in assessing food quality, an environmental index needs to be established taking into account carbon footprint, water and energy use. The discussion within the group working on environmental issues highlighted the importance of focusing on whole life cycle analysis in the mitigation area, while the adaptation strategy should be based on selection for profitable animals under different production systems. In summary, a fundamental shift in designing our production systems is required to help ensure present needs for animal products are met without compromising future generations.
Improving the efficiency of energy utilisation in cattle
Authors: Reynolds C. K. , Crompton L. A. , Mills J. A. N.
Published: December 2010

The efficiency of energy utilisation in cattle is a determinant of the profitability of milk and beef production, as well as their environmental impact. At an animal level, meat and milk production by ruminants is less efficient than pig and poultry production, in part due to lower digestibility of forages compared with grains. However, when compared on the basis of human-edible inputs, the ruminant has a clear efficiency advantage. There has been recent interest in feed conversion efficiency (FCE) in dairy cattle and residual feed intake, an indicator of FCE, in beef cattle. Variation between animals in FCE may have genetic components, allowing selection for animals with greater efficiency and reduced environmental impact. A major source of variation in FCE is feed digestibility, and thus approaches that improve digestibility should improve FCE if rumen function is not disrupted. Methane represents a substantial loss of digestible energy from rations. Major determinants of methane emission are the amount of feed consumed and the proportions of forage and concentrates fed. In addition, feeding fat has long been known to reduce methane emission. A myriad of other supplements and additives are currently being investigated as mitigators of methane emission, but in many cases compounds effective in sheep are ineffective in lactating dairy cows. Ultimately, the adoption of ‘best practice’ in diet formulation and management may be the most effective option for reducing methane. In assessing the efficiency of energy use for milk and meat production by cattle, and their environmental impact, it is imperative that comparisons be made at a systems level, and that the wider social and economic implications of mitigation policy are considered.
Longitudinal evidence for diminished frontal cortex function in aging
Authors: Nyberg Lars , Salami Alireza , Andersson Mikael , Eriksson Johan , Kalpouzos Grégoria , Kauppi Karolina , Lind Johanna , Pudas Sara , Persson Jonas , Nilsson Lars-Göran
Published: December 2010

Cross-sectional estimates of age-related changes in brain structure and function were compared with 6-y longitudinal estimates. The results indicated increased sensitivity of the longitudinal approach as well as qualitative differences. Critically, the cross-sectional analyses were suggestive of age-related frontal overrecruitment, whereas the longitudinal analyses revealed frontal underrecruitment with advancing age. The cross-sectional observation of overrecruitment reflected a select elderly sample. However, when followed over time, this sample showed reduced frontal recruitment. These findings dispute inferences of true age changes on the basis of age differences, hence challenging some contemporary models of neurocognitive aging, and demonstrate age-related decline in frontal brain volume as well as functional response.
Transfer of a prion strain to different hosts leads to emergence of strain variants
Authors: Mahal Sukhvir P. , Browning Shawn , Li Jiali , Suponitsky-Kroyter Irena , Weissmann Charles
Published: December 2010

Prions consist mainly of PrP
Sc
, a pathogenic conformer of host-encoded PrP
C
. Prion populations with distinct phenotypes but associated with PrP
Sc
, having the same amino acid sequence, constitute distinct strains. Strain identity is thought to be encoded by the conformation of PrP
Sc
and to be maintained by seeded conversion. Prion strains can be distinguished by the cell panel assay, which measures their ability to infect distinct cell lines. Brain-derived 22L prions characteristically are able to infect R33 cells (i.e., are “R33 competent”), as well as PK1 cells in the presence of the inhibitor swainsonine (i.e. are “swa resistant”). Here we report that 22L prions retained their characteristic cell tropism and swa resistance when transferred from brain to R33 cells. However, when transferred from the R33 cells to PK1 cells, they gradually became R33 incompetent and swa sensitive, unless the transfer was in the presence of swa, in which case swa resistance and R33 competence were retained. PrP
Sc
associated with swa-resistant/R33-competent and swa-sensitive/R33-incompetent prions had different conformational stabilities. When cloned R33-incompetent/swa-sensitive prions were again propagated in brain, their properties gradually reverted to those of the original brain-derived 22L prions. Our results support the view that 22L prion populations are heterogeneous and that distinct prion variants are selected in different cellular environments.
Collocations and Idioms and Their Translatability
Authors: Bateni Mohammad Reza
Published: December 2010

A collocation can be defined as a sequence of words which co-occur more than would be expected by chance. Collocations impose constraints on how words can be used together. An idiom is an expression whose meaning cannot be deduced from the literal definitions and the arrangement of its parts, but refers instead to a figurative meaning that is known only through common use. In this paper I will attempt to expand on these notions. For further clarification, I will compare and contrast some examples from English and Persian.
A Socio-Historical Approach to Poetic Origins of Persian Proverbs
Authors: Hadissi Korosh
Published: December 2010

The connection between proverbs and poetry is a profound and ancient one. The classical poets often cited well-known proverbs to attract and engage common people. In the case of legendary poets, some of their enchanting poems were well received and commonly repeated by ordinary people and gradually became famous proverbs themselves. More than any other Persian poets, Rumi, Sádi and Ferdowsi cited and created proverbs. Due to the condensed structure of maxims, often the preconditions and teachings of poets became distorted. As shown here, even the logical and philosophical views of Rumi and Khayyam were not spared. This is a common phenomenon in all languages, but can be reversed by finding their poetic roots and rediscovering the lost lessons of master poets. Nevertheless, the majority of proverbs are created by rural people to share, reason, and transfer their everyday life experiences to their children, one another and future generations.
Esmail Khoi: The Poet as Observer and Creative Explorer
Authors: Nakjavani Erik
Published: December 2010

This article focuses on how Esmail Khoi poetically inhabits the world of his poetry as an observer and visionary explorer. Its aim is to make manifest how he engages his readers in reciprocal poetic dialogues to communicate his unique vision of the lived world. The dialogic function of his poetry is then examined as the ground of emergence of an experiential poetic mode of knowledge of the human condition. The article also considers Khoi's poetry as work done in the fields of language, alchemically transmuting everyday language of communication into poetic discourse. Finally, an analysis of his poem “To the Aged Mulberry Branch” explicates how Khoi can create a world of imagination whole and entire unto itself by his minimalist approach to poetry.
Innovation Policy as Industrial Policy: Some Lessons from Hamburg's Regional Innovation System
Authors: Vorley Tim , Nelles Jen
Published: December 2010

The widespread transformation of the economic base has seen the decline of traditional manufacturing economies and the rise of knowledge-based economies. Consequently, conventional manufacturing-oriented industrial policy has become ‘future orientated’ towards the challenges of the knowledge-based economies, and increasingly replaced by innovation policy. Drawing upon original empirical research on Hamburg's regional innovation system, this paper unravels how innovation policy has increasingly sought to embed and realise the value of universities and publicly-funded research institutions by positioning them at the core of the regional innovation system. The outcome is that innovation policy plays an important catalytic role in promoting technology transfer and knowledge exchange. However, the success of this new agenda is shown to depend on its acceptance and adaptation by universities and publicly-funded research institutes. This study of Hamburg reveals how, when effectively achieved, innovation policy as a form of future-orientated industrial policy can restructure local economies as centres of high-technology research and development with strong science-industry links.