bluuebunny/crossref_metadata_2025 huggingface dataset:
Split families unified
Authors: Craig Nathaniel , Dimopoulos Savas , Gherghetta Tony
Published: April 2012

Abstract

We present a simple supersymmetric model of split families consistent with flavor limits that preserves the successful prediction of gauge coupling unification and naturally accounts for the Higgs mass. The model provides an intricate connection between the Standard Model flavor hierarchy, supersymmetric flavor problem, unification and the Higgs mass. In particular unification favors a naturally large Higgs mass from D-term corrections to the quartic couplings in the Higgs potential. The unification scale is lowered with a stable proton that can account for the success of b − τ Yukawa coupling unification. The sparticle spectrum is similar to that of natural supersymmetry, as motivated by the supersymmetric flavor problem and recent LHC bounds, with a heavy scalar particle spectrum except for a moderately light stop required for viable electroweak symmetry breaking. Finally, Higgs production and decays, NLSP decays, and new states associated with extending the Standard Model gauge group above the TeV scale provide signatures for experimental searches at the LHC.
Is there a genetic cause of appetite loss?—an explorative study in 1,853 cancer patients
Authors: Solheim Tora S. , Fayers Peter M. , Fladvad Torill , Tan Ben , Skorpen Frank , Fearon Kenneth , Baracos Vickie E. , Klepstad Pål , Strasser Florian , Kaasa Stein
Published: April 2012

Background

Appetite loss has a major impact on cancer patients. It is exceedingly prevalent, is a prognostic indicator and is associated with inferior quality of life. Cachexia is a multi‐factorial syndrome defined by a negative protein and energy balance, driven by a variable combination of reduced food intake and abnormal metabolism. Not all cancer patients that experience weight loss have appetite loss, and the pathophysiology between cachexia and appetite loss may thus be different. Knowledge of pathophysiology of appetite loss in cancer patients is still limited. The primary object of this study was to explore the association with 93 predefined candidate single‐nucleotide polymorphisms (SNPs) and appetite loss in cancer patients to possibly generate new theories of the pathophysiology of the condition.

Methods

A total of 1,853 cancer patients were phenotyped according to appetite loss and then genotyped.

Results

After allowing for multiple testing, there was no statistically significant association between any of the SNPs analysed and appetite loss. The ten most significant SNPs in the co‐dominant model had observed odds ratios varying from 0.72 to 1.28.

Conclusions

This large exploratory study could not find any associations with loss of appetite and 93 SNPs with a potential to be involved in appetite loss in cancer patients. This does not however rule out genes putative role in the development of the symptom, but the observed odds ratios are close to one which makes it unlikely that any of the individual SNPs explored in the present study have great importance.

Electronic supplementary material

The online version of this article (doi:10.1007/s13539‐012‐0064‐8) contains supplementary material, which is available to authorized users.
Beyond ‘furballs’ and ‘dumpling soups’ – towards a molecular architecture of signaling complexes and networks
Authors: Lewitzky Marc , Simister Philip C. , Feller Stephan M.
Published: April 2012

The molecular architectures of intracellular signaling networks are largely unknown. Understanding their design principles and mechanisms of processing information is essential to grasp the molecular basis of virtually all biological processes. This is particularly challenging for human pathologies like cancers, as essentially each tumor is a unique disease with vastly deranged signaling networks. However, even in normal cells we know almost nothing. A few ‘signalosomes’, like the COP9 and the TCR signaling complexes have been described, but detailed structural information on their architectures is largely lacking. Similarly, many growth factor receptors, for example EGF receptor, insulin receptor and c‐Met, signal via huge protein complexes built on large platform proteins (Gab, Irs/Dok, p130Cas[BCAR1], Frs families etc.), which are structurally not well understood. Subsequent higher order processing events remain even more enigmatic. We discuss here methods that can be employed to study signaling architectures, and the importance of too often neglected features like macromolecular crowding, intrinsic disorder in proteins and the sophisticated cellular infrastructures, which need to be carefully considered in order to develop a more mature understanding of cellular signal processing.
Predictors of Clinical Outcome in Fibromyalgia After a Brief Interdisciplinary Fibromyalgia Treatment Program: Single Center Experience
Authors: Oh Terry H. , Hoskin Tanya L. , Luedtke Connie A. , Weingarten Toby N. , Vincent Ann , Kim Chul H. , Thompson Jeffrey M.
Published: April 2012

Objective

To determine which patient characteristics are closely associated with a positive response to a brief interdisciplinary fibromyalgia treatment program (FTP).

Design

A prospective cohort study.

Setting

FTP at a tertiary medical center.

Participants

A total of 536 patients with a confirmed diagnosis of fibromyalgia who underwent the FTP and completed the Fibromyalgia Impact Questionnaire (FIQ) at baseline and 6‐12 months after treatment.

Interventions

A brief 1.5‐day interdisciplinary FTP, which included evaluation with a registered nurse and a physician for a diagnosis or confirmation of fibromyalgia, fibromyalgia education, interactive self management session, and physical and occupational therapy.

Main Outcome Measurements

The responder definition was an improvement of 14% or more in the FIQ total score from their baseline to 6‐12 months after treatment.

Results

Mean (standard deviation) age of our patients was 50.3 ± 13.0 years; 515 women (96%) and 23 men (4%). Two hundred forty‐eight patients (46%) met the responder definition at 6‐12 months follow‐up. In an univariate analysis, younger age (P = .008), college or higher education (P = .02), fewer tender points (P = .048), and higher FIQ depression subscore (P = .02) significantly predicted positive response. In a multivariate analysis, these factors all remained statistically significant. In addition, a positive abuse history became significant (P = .03). There was no significant association for gender, duration of symptoms, marital status, employment, smoking status, or 3 numeric rating scale pain scores.

Conclusions

Patients with younger age, more years of education (with college or graduate degree), higher baseline FIQ depression score, lower tender point count, and absent abuse history experience greater benefit from a brief FTP.
Changes in turbulent dissipation in a channel flow with oscillating walls
Authors: Ricco Pierre , Ottonelli Claudio , Hasegawa Yosuke , Quadrio Maurizio
Published: April 2012

Harmonic oscillations of the walls of a turbulent plane channel flow are studied by direct numerical simulations to improve our understanding of the physical mechanism for skin-friction drag reduction. The simulations are carried out at constant pressure gradient in order to define an unambiguous inner scaling: in this case, drag reduction manifests itself as an increase of mass flow rate. Energy and enstrophy balances, carried out to emphasize the role of the oscillating spanwise shear layer, show that the viscous dissipation of the mean flow and of the turbulent fluctuations increase with the mass flow rate, and the relative importance of the latter decreases. We then focus on the turbulent enstrophy: through an analysis of the temporal evolution from the beginning of the wall motion, the dominant, oscillation-related term in the turbulent enstrophy is shown to cause the turbulent dissipation to be enhanced in absolute terms, before the slow drift towards the new quasi-equilibrium condition. This mechanism is found to be responsible for the increase in mass flow rate. We finally show that the time-average volume integral of the dominant term is linearly related to the drag reduction.
Conservation needs of the coconut crab Birgus latro on the Nicobar Islands, India
Authors: Patankar Vardhan , D'souza Elrika
Published: April 2012

We describe the distribution of the coconut crab Birgus latro, categorized as Data Deficient on the IUCN Red List, local perspectives towards the species, and its conservation needs on the Nicobar Islands in the eastern Indian Ocean. The species is threatened with extinction across most of its range and in India it is found only on a few islands in the Andaman and Nicobar archipelagoes. We carried out informal discussions with Nicobari communities to examine issues regarding conservation of the species and conducted timed searches in areas where coconut crabs were likely to be found. The discussions revealed that there are social taboos against hunting the coconut crab on most of the Nicobar Islands. However, on some islands these taboos are not being followed and community members may hunt the crab for consumption. Athough the coconut crab is legally protected under the Indian Wildlife Protection Act none of the villagers were aware of this. Of the six islands surveyed we recorded the presence of 17 and 14 crabs on two islands, respectively. On four islands villagers reported the presence of the crab prior to the tsunami of 2004, and on two of these islands the species may now be locally extinct. A small population size and a fragmented distribution in areas of coconut plantations suggest that the species is threatened. We recommend monitoring and detailed research on the ecology and genetics of the coconut crab, along with community-based conservation initiatives to conserve the species and its habitat.
Short-term SSRI treatment normalises amygdala hyperactivity in depressed patients
Authors: Godlewska B. R. , Norbury R. , Selvaraj S. , Cowen P. J. , Harmer C. J.
Published: April 2012

Background

Antidepressant drugs such as selective serotonin re-uptake inhibitors (SSRIs) remediate negative biases in emotional processing in depressed patients in both behavioural and neural outcome measures. However, it is not clear if these effects occur before, or as a consequence of, changes in clinical state.

Method

In the present study, we investigated the effects of short-term SSRI treatment in depressed patients on the neural response to fearful faces prior to clinical improvement in mood. Altogether, 42 unmedicated depressed patients received SSRI treatment (10 mg escitalopram daily) or placebo in a randomised, parallel-group design. The neural response to fearful and happy faces was measured on day 7 of treatment using functional magnetic resonance imaging. A group of healthy controls was imaged in the same way.

Results

Amygdala responses to fearful facial expressions were significantly greater in depressed patients compared to healthy controls. However, this response was normalised in patients receiving 7 days treatment with escitalopram. There was no significant difference in clinical depression ratings at 7 days between the escitalopram and placebo-treated patients.

Conclusions

Our results suggest that short-term SSRI treatment in depressed patients remediates amygdala hyperactivity in response to negative emotional stimuli prior to clinical improvement in depressed mood. This supports the hypothesis that the clinical effects of antidepressant treatment may be mediated in part through early changes in emotional processing. Further studies will be needed to show if these early effects of antidepressant medication predict eventual clinical outcome.
Doing Time: A Theory of the Constitution
Authors: Orren Karen
Published: April 2012

Proceeding inductively, starting with three standard examples of major constitutional change, this short essay offers a theory of the Constitution, derived from its historical imposition on the criminal law. The theory proposes to unite constitutional provision, structure, and operations within a single framework over time.
Three‐dimensional stochastic estimation of porosity distribution: Benefits of using ground‐penetrating radar velocity tomograms in simulated‐annealing‐based or Bayesian sequential simulation approaches
Authors: Dafflon B. , Barrash W.
Published: April 2012

Estimation of the three‐dimensional (3‐D) distribution of hydrologic properties and related uncertainty is a key for improved predictions of hydrologic processes in the subsurface. However it is difficult to gain high‐quality and high‐density hydrologic information from the subsurface. In this regard a promising strategy is to use high‐resolution geophysical data (that are relatively sensitive to variations of a hydrologic parameter of interest) to supplement direct hydrologic information from measurements in wells (e.g., logs, vertical profiles) and then generate stochastic simulations of the distribution of the hydrologic property conditioned on the hydrologic and geophysical data. In this study we develop and apply this strategy for a 3‐D field experiment in the heterogeneous aquifer at the Boise Hydrogeophysical Research Site and we evaluate how much benefit the geophysical data provide. We run high‐resolution 3‐D conditional simulations of porosity with both simulated‐annealing‐based and Bayesian sequential approaches using information from multiple intersecting crosshole gound‐penetrating radar (GPR) velocity tomograms and neutron porosity logs. The benefit of using GPR data is assessed by investigating their ability, when included in conditional simulation, to predict porosity log data withheld from the simulation. Results show that the use of crosshole GPR data can significantly improve the estimation of porosity spatial distribution and reduce associated uncertainty compared to using only well log measurements for the estimation. The amount of benefit depends primarily on the strength of the petrophysical relation between the GPR and porosity data, the variability of this relation throughout the investigated site, and lateral structural continuity at the site.
Decadal variability and a recent amplification of the summer Beaufort Sea High
Authors: Moore G. W. K.
Published: April 2012

The Beaufort Sea High (BSH), an anti‐cyclone over the Beaufort Sea, is an important feature of the summer atmospheric circulation over the Arctic Ocean. For example, years characterized by low Arctic sea ice extent are typically associated with the presence of a stronger BSH; with the opposite occurring during years with high sea ice extent. In this paper, we show that there exists variability on the decadal time scale in the intensity and location of the summer BSH. We also show that there has been a trend towards a stronger summer BSH that began in the late 1990s. This trend is shown to be coincident with a tendency towards a reduction in cyclogenesis during the summer over the Beaufort Sea. We argue that that these trends are the result of a warming of the troposphere in the western Arctic and the concomitant reduction in baroclincity.
Shortcomings of InSAR for studying megathrust earthquakes: The case of the Mw9.0 Tohoku‐Oki earthquake
Authors: Feng Guangcai , Jónsson Sigurjón
Published: April 2012

Interferometric Synthetic Aperture Radar (InSAR) observations are sometimes the only geodetic data of large subduction‐zone earthquakes. However, these data usually suffer from spatially long‐wavelength orbital and atmospheric errors that can be difficult to distinguish from the coseismic deformation and may therefore result in biased fault‐slip inversions. To study how well InSAR constrains fault‐slip of large subduction zone earthquakes, we use data of the 11 March 2011 Tohoku‐Oki earthquake (Mw9.0) and test InSAR‐derived fault‐slip models against models constrained by GPS data from the extensive nationwide network in Japan. The coseismic deformation field was mapped using InSAR data acquired from multiple ascending and descending passes of the ALOS and Envisat satellites. We then estimated several fault‐slip distribution models that were constrained using the InSAR data alone, onland and seafloor GPS/acoustic data, or combinations of the different data sets. Based on comparisons of the slip models, we find that there is no real gain by including InSAR observations for determining the fault slip distribution of this earthquake. That said, however, some of the main fault‐slip patterns can be retrieved using the InSAR data alone when estimating long wavelength orbital/atmospheric ramps as a part of the modeling. Our final preferred fault‐slip solution of the Tohoku‐Oki earthquake is based only on the GPS data and has maximum reverse‐ and strike‐slip of 36.0 m and 6.0 m, respectively, located northeast of the epicenter at a depth of 6 km, and has a total geodetic moment is 3.6 × 1022 Nm (Mw 9.01), similar to seismological estimates.
The dynamical link between surface cyclones, upper‐tropospheric Rossby wave breaking and the life cycle of the Scandinavian blocking
Authors: Michel C. , Rivière G. , Terray L. , Joly B.
Published: April 2012

The Scandinavian blocking (SB) is a well‐known quasi‐stationary state of the atmospheric flow and one of the four main weather regimes over the Euro‐Atlantic domain in winter. The aim of our study is to analyze the link between surface cyclones, upper‐tropospheric Rossby wave breakings and the life cycle of SB using ERA‐40 reanalysis. The onset and decay of SB are studied by considering the preferential transitions from the zonal regime to SB and from SB to the Greenland anticyclone regime. During the SB onset, Atlantic cyclones have straight trajectories that extend toward the north of Scandinavia. These surface cyclones are associated with anticyclonic wave breakings in the upper troposphere over Europe. During the SB decay, cyclones are much less present in the eastern part of the Atlantic and most of them present curved trajectories in mid‐Atlantic. They are shown to be linked to cyclonic wave breakings to the south of Greenland.
Three-dimensional particle-in-cell simulation of discharge characteristics in cylindrical anode layer hall plasma accelerator
Authors: Geng S. F. , Qiu X. M. , Cheng C. M. , Chu Paul. K. , Tang D. L.
Published: April 2012

A current drop is found when the discharge voltage is increased in the cylindrical anode layer hall plasma accelerator and three-dimensional particle-in-cell simulation is performed to investigate the phenomenon. The simulation results which agree with experiments show that the ion density in the discharge region does not always rise when the discharge voltage is increased and the ion density reaches a maximum value at the appropriate voltage. This phenomenon is considered to be the macroscopic ramification of the change in the ionization cross section as the electron energy varies. With regard to Ar+, the largest ionization cross section appears when the electron energy is 45–110 eV. In the hall plasma accelerator, the electron drift speed is governed by E/B and controls the electron energy. Finally, the cross section of producing Ar+ is determined by E/B. Our analysis reveals that the proper E/B value in the ionization region is 2.81 × 106 m/s to 4.40 × 106 m/s for argon.
Scattering of nitrogen molecules by silver atoms
Authors: Loreau Jérôme , Zhang Peng , Dalgarno Alexander
Published: April 2012

We present a quantal study of the rotationally elastic and inelastic scattering of Ag and N2, with the nitrogen molecule treated as a rigid rotor. The two-dimensional potential energy surface of the AgN2 complex is obtained ab initio by means of the spin unrestricted coupled-cluster method with single, double, and perturbative triple excitations. The global minimum is found to be located at an internuclear distance of 8.13 a0 and an angle of 127.2°. The long-range part of the potential is constructed from the dynamic electric dipole polarizabilities of Ag and N2. Elastic, excitation, and relaxation cross sections and rates are calculated for energies between 0.1 and 5000 cm−1. The momentum transfer cross sections and rates are also computed. Finally, we compare the cross sections for Ag–N2 and Na–N2 to explore the possibility of using silver instead of sodium in experimental tests.
Effect of oxidizing the ferromagnetic electrode in magnetic tunnel junctions on tunneling magnetoresistance
Authors: Joo Sungjung , Jung K. Y. , Lee B. C. , Kim Tae-Suk , Shin K. H. , Jung Myung-Hwa , Rho K.-J. , Park J.-H. , Hong Jinki , Rhie K.
Published: April 2012

The ferromagnetic layer in magnetic tunnel junctions (MTJs) was oxidized with varying O2 concentrations, and the corresponding effect on spin-dependent transport was studied. As expected from our previous results for MTJs with an over-oxidized AlOx tunnel barrier, a partially oxidized ferromagnetic layer plays an important role in spin-dependent transport. As the temperature is lowered, the junction resistance increases dramatically, and the tunneling magnetoresistance (TMR) is strongly suppressed. Increasing the O2 concentration enhances the increase of resistance and suppression of TMR. This work supports our previous conclusion that oxidizing the ferromagnetic layer generates localized magnetic moments, which act as a scattering center for spin-polarized tunneling electrons.
High-speed waveguide-coupled graphene-on-graphene optical modulators
Authors: Koester Steven J. , Li Mo
Published: April 2012

An electro-absorption optical modulator concept based upon a dual-graphene layer is presented. The device consists of a silicon-on-insulator waveguide upon which two graphene layers reside, separated by a thin insulating region. The lower graphene acts as a tunable absorber, while the upper layer functions as a transparent gate electrode. Calculations based upon realistic graphene material properties show that 3-dB bandwidths over 120 GHz (30 GHz) are achievable at near- (λ = 1.55 μm) and mid- (λ = 3.5 μm) infrared bands. The effect of background doping and potential fluctuations on the bandwidth, modulation depth, and insertion loss are also quantified.
Experimental evidence for the correlation between the weak inversion hump and near midgap states in dielectric/InGaAs interfaces
Authors: Krylov Igor , Kornblum Lior , Gavrilov Arkady , Ritter Dan , Eizenberg Moshe
Published: April 2012

Temperature dependent capacitance–voltage (C-V) and conductance-voltage (G-V) measurements were performed to obtain activation energies (EA) for weak inversion C-V humps and parallel conductance peaks in Al2O3/InGaAs and Si3N4/InGaAs gate stacks. Values of 0.48 eV (slightly more than half of the band gap of the studied In0.53Ga0.47As) were obtained for EA of both phenomena for both gate dielectrics studied. This indicates an universal InGaAs behavior and shows that both phenomena are due to generation-recombination of minority carriers through near midgap located interface states. The C-V hump correlates with the interface states density (Dit) and can be used as a characterization tool for dielectric/InGaAs systems.
Wind energy assessment for five locations in Saudi Arabia
Authors: Eltamaly Ali M. , Farh Hassan M.
Published: April 2012

This paper introduces a computer program to choose the most suitable wind turbine for each site according to technical and economical assessments. The criterion for choosing the most suitable wind turbine for each site is according to which wind turbine and site give a maximum capacity factor and minimum cost of energy ($/kWh). This criterion is used because the decision of matching which depends only on maximum capacity factor is not enough because capacity factor is independent of rated power of wind turbine. Therefore, two wind turbines with the same performance parameters but different rated power get the same capacity factor for the same site, but it does not get the same cost of energy ($/kWh). The data of five locations in Saudi Arabia have been applied to the computer program. The five locations are Yanbou, Dhahran, Douhlom, Riyadh, and Qaisumah. The wind turbine parameters such as hub height, rated power, cut-in, rated, and furling wind speeds for ten commercial wind turbines are collected. The Weibull parameters have been estimated numerically and graphically for these five locations. The values of Weibull parameters obtained graphically are similar to the numerical one. Three methods have been used for estimating the cost of energy. The results from these three methods have been compared, and the suitable one for Saudi Arabia economics has been selected.
Asymptotic behavior of the Verblunsky coefficients for the OPUC with a varying weight
Authors: Poplavskyi M.
Published: April 2012

We present an asymptotic analysis of the Verblunsky coefficients for the polynomials orthogonal on the unit circle with the varying weight e−nV(cos x), assuming that the potential V has four bounded derivatives on [−1, 1] and the equilibrium measure has a one interval support. We obtain the asymptotics as a solution of the system of “string” equations.
Impact and wetting behaviors of impinging microdroplets on superhydrophobic textured surfaces
Authors: Hee Kwon Dae , Joon Lee Sang
Published: April 2012

The impact and wetting behaviors of impinging microdroplets on textured surfaces are investigated using high-speed imaging. Microdroplets with diameters less than 50 μm are ejected using a piezoelectric printhead with controlled Weber numbers. The impact behaviors are clearly observed, and the detailed mechanisms are explained according to the Weber number and wetting states of the impinging droplets. Moreover, the transition phenomena from bouncing to non-bouncing are clearly observed. The impalement transition, which has been explained by wetting pressures, is also examined in this study.
Using carbon chains to mediate magnetic coupling in zigzag graphene nanoribbons
Authors: Kan Min , Zhou Jian , Li Yawei , Sun Qiang
Published: April 2012

Graphene nanoribbon and atomic carbon chain are allotropes of carbon, attracting tremendous attention from multidisciplinary areas ranging from nano physics to astrophysics. Here, first-principles calculations based on density-functional theory are carried out to study the ferromagnetic coupling in zigzag-edged graphene nanoribbons linked by carbon chains. Compared to the existing methods for ferromagnetic graphene nanoribbons, carbon chain linkage is found to be more effective for larger magnetic exchange energy and also be more flexible in tuning the electronic structure and magnetism.
Tunneling conductivity in composites of attractive colloids
Authors: Nigro B. , Grimaldi C. , Miller M. A. , Ryser P. , Schilling T.
Published: April 2012

In conductor-insulator nanocomposites in which conducting fillers are dispersed in an insulating matrix, the electrical connectedness is established by inter-particle tunneling or hopping processes. These systems are intrinsically non-percolative and a coherent description of the functional dependence of the conductivity σ on the filler properties, and in particular of the conductor-insulator transition, requires going beyond the usual continuum percolation approach by relaxing the constraint of a fixed connectivity distance. In this article, we consider dispersions of conducting spherical particles which are connected to all others by tunneling conductances and which are subjected to an effective attractive square-well potential. We show that the conductor-insulator transition at low contents ϕ of the conducting fillers does not determine the behavior of σ at larger concentrations, in striking contrast to what is predicted by percolation theory. In particular, we find that at low ϕ the conductivity is governed almost entirely by the stickiness of the attraction, while at larger ϕ values σ depends mainly on the depth of the potential well. As a consequence, by varying the range and depth of the potential while keeping the stickiness fixed, composites with similar conductor-insulator transitions may display conductivity variations of several orders of magnitude at intermediate and large ϕ values. By using a recently developed effective medium theory and the critical path approximation, we explain this behavior in terms of dominant tunneling processes which involve inter-particle distances spanning different regions of the square-well fluid structure as ϕ is varied. Our predictions could be tested in experiments by changing the potential profile with different depletants in polymer nanocomposites.
Charge trap flash memory using ferroelectric materials as a blocking layer
Authors: Seo Yujeong , An Ho-Myoung , Yeong Song Min , Geun Kim Tae
Published: April 2012

In this paper, we propose a charge-trap flash memory device using a ferroelectric material, Sr0.7Bi2.3Nb2O9 (SBN), with spontaneous polarization as a blocking layer. This device consists of metal/SBN/nitride/oxide/silicon and has an advantage in the carrier injection into the nitride from the silicon due to polarization charges formed in the ferroelectric material. Compared to conventional metal/oxide/nitride/oxide/silicon memory devices, the proposed devices showed a larger memory window (7 V), faster program/erase (P/E) speeds (100/500 μs), and higher endurance (105 P/E cycles) with comparable retention properties.
Enhanced dielectric and piezoelectric properties of xBaZrO3-(1−x)BaTiO3 ceramics
Authors: Dong Liang , Stone Donald S. , Lakes Roderic S.
Published: April 2012

xBaZrO3-(1−x)BaTiO3 solid solutions (x = 0, 0.04, 0.06, 0.08, 0.12, and 0.18) synthesized via conventional solid state reaction method exhibit piezoelectric coefficients comparable to those of “hard” PZT-8, PZT-4, and even “soft” PZT-5 A. Doping also improves the poling efficiency of xBaZrO3-(1−x)BaTiO3 ceramics. Study of temperature dependence of the dielectric and piezoelectric properties reveal the following. Doping lowered the Curie point but raised the temperatures of the other two transformations. The diffused phase transition behavior has been enhanced with increasing content of BaZrO3, but x ≤ 0.18 is not enough to show a relaxor behavior. Piezoelectric responses show peaks at transformation temperatures and exhibit the best stability in the orthorhombic phase. Significant improvement in room temperature piezoelectric and electromechanical responses (d33 = 420pC/N, d31 = −138pC/N, and kp = 49%) comparable to PZT-5 A is achieved at a composition of x = 0.06 (1400 °C 100 h sintered), which brings the rhombohedral-orthorhombic transition to the ambient temperature. Enhanced piezoelectric properties are mainly attributed to a series of microscopic phase transformations due to the presence of internal structural gradient. Other possible contributions such as domain structures and constrained negative stiffness effect have also been discussed.
Thermo-economic assessment of end user value in home and community scale renewable energy systems
Authors: Oliver David , Groulx Dominic
Published: April 2012

This study employs thermo-economic analysis to establish a homeowner-centric valuation of renewable energy technologies. The evaluation methodology is illustrated using several classes of renewable energy technology, including, ground-source heat pumps, wind turbines, photovoltaic panels, and solar thermal water heaters. Energy systems employing each of these technologies are examined when servicing the typical domestic energy loads of a single-detached home. Through the analysis, it is learned that single-home photovoltaic systems produce energy at an annual cost approximately four times that of grid electricity, while wind energy systems deliver this energy at approximately twice the cost of grid electricity. Further, single-detached homeowners currently heating with fuel oil and/or grid electricity may expect to save between $1000 and $1800 per year when switching to a ground-source heat pump system; whereas those considering the implementation of a solar thermal water heater can expect to spend an additional $245 per year for hot water. Investigation of larger scale renewable systems examined the performance of wind turbines and ground-source heat pumps when serving groups of single-detached homes; wind turbines were found to exhibit significant economies of scale.
Temperature curve of magnetization and left-handed properties of La0.775Sr0.225MnO3
Authors: Belozorov D. P. , Kalmykova T. V. , Tarapov S. I. , Pogorily A. M. , Tovstolytkin A. I. , Belous A. G. , Solopan S. A.
Published: April 2012

The left-handed features of Sr doped manganite lanthanum ceramics La0.775Sr0.225MnO3 in the vicinity of its Curie temperature are studied. The left-handed features are responsible for appearance of the additional transparency peak in the forbidden band of the photonic crystal bounded with the above manganite. The magnitude of the critical exponent β (β ∼ 0.50) determined in the work agrees with results reported in the literature and allows supposing that long-range interactions play an important role in the phase transition from conductive ferromagnetic to nonconductive dielectric paramagnetic state of the manganite in its Curie point.
Evolution of electrical performance of ZnO-based thin-film transistors by low temperature annealing
Authors: Zhang J. , Li X. F. , Lu J. G. , Wu P. , Huang J. , Wang Q. , Lu B. , Zhang Y. Z. , Zhao B. H. , Ye Z. Z.
Published: April 2012

The effects of post-annealing on performance of ZnO-based thin-film transistors (TFTs) fabricated at room temperature were investigated. It was observed that high-temperature annealing resulted in a large decrease in resistivity of the ZnO channel layer and caused a large off-state current for ZnO TFTs, while low-temperature annealing had little effect on the off-state current. The evolution of electrical performance of ZnO TFTs annealed at a lower temperature showed that the threshold voltage decreased greatly and the sub-threshold slope improved evidently without great change of the resistivity of the ZnO channel as the annealing time prolonged. The possible mechanism is that the traps have been removed without activating the donor defects in the ZnO channel layer.
Aesthetic Judgment of Triangular Shape: Compactness and Not the Golden Ratio Determines Perceived Attractiveness
Authors: Friedenberg Jay
Published: April 2012

Many studies over a period of more than a century have investigated the influence of the golden ratio on perceived geometric beauty. Surprisingly, very few of these studies used triangular shapes. In Experiment 1, we presented right triangles that differed in regard to their elongation determined by increasing the length of one side relative to another. Attractiveness ratings did not peak at the golden ratio, but there was a very strong influence of axis ratio overall. Participant ratings were a negative decreasing function of ratio. Triangles that pointed upward were judged as significantly more attractive than those that pointed down. We interpret these results according to a compactness hypothesis: triangles that are more compact are less likely to move or break and are thus considered more pleasing. Orientation also affects aesthetics. Upward-pointing triangles with a base parallel to the ground, regardless of their compactness, are also considered more perceptually stable and attractive. These findings were replicated across stimulus type in a second experiment with isosceles triangles and across testing procedure in a third experiment using a paired comparison technique.
On the Matching of Seen and Felt Shape by Newly Sighted Subjects
Authors: Schwenkler John
Published: April 2012

How do we recognize identities between seen shapes and felt ones? Is this due to associative learning, or intrinsic connections these sensory modalities? We can address this question by testing the capacities of newly sighted subjects to match seen and felt shapes, but only if the subjects can see the objects well enough to form adequate visual representations of their shapes. In light of this, a recent study by R. Held and colleagues fails to demonstrate that their newly sighted subjects' inability to match seen and felt shape was due to a lack of intermodal connections rather than a purely visual deficit, as the subjects may not have been able visually to represent 3D shape in the perspective-invariant manner required for intermodal matching. However, the study could be modified in any of several ways to help avoid this problem.
Structural basis of species-specific endotoxin sensing by innate immune receptor TLR4/MD-2
Authors: Ohto Umeharu , Fukase Koichi , Miyake Kensuke , Shimizu Toshiyuki
Published: April 2012

Lipopolysaccharide (LPS), also known as endotoxin, activates the innate immune response through toll-like receptor 4 (TLR4) and its coreceptor, MD-2. MD-2 has a unique hydrophobic cavity that directly binds to lipid A, the active center of LPS. Tetraacylated lipid IVa, a synthetic lipid A precursor, acts as a weak agonist to mouse TLR4/MD-2, but as an antagonist to human TLR4/MD-2. However, it remains unclear as to how LPS and lipid IVa show agonistic or antagonistic activities in a species-specific manner. The present study reports the crystal structures of mouse TLR4/MD-2/LPS and TLR4/MD-2/lipid IVa complexes at 2.5 and 2.7 Å resolutions, respectively. Mouse TLR4/MD-2/LPS exhibited an agonistic “m”-shaped 2:2:2 complex similar to the human TLR4/MD-2/LPS complex. Mouse TLR4/MD-2/lipid IVa complex also showed an agonistic structural feature, exhibiting architecture similar to the 2:2:2 complex. Remarkably, lipid IVa in the mouse TLR4/MD-2 complex occupied nearly the same space as LPS, although lipid IVa lacked the two acyl chains. Human MD-2 binds lipid IVa in an antagonistic manner completely differently from the way mouse MD-2 does. Together, the results provide structural evidence of the agonistic property of lipid IVa on mouse TLR4/MD-2 and deepen understanding of the ligand binding and dimerization mechanism by the structurally diverse LPS variants.
In search of meaning: Semantic effects on past-tense inflection
Authors: Butler Rebecca , Patterson Karalyn , Woollams Anna M.
Published: April 2012

Within single-mechanism connectionist models of inflectional morphology, generating the past-tense form of a verb depends upon the interaction of semantic and phonological representations, with semantic information being particularly important for irregular or exception verbs. We assessed this hypothesis in two experiments requiring normal speakers to produce the past tense from a verb stem that takes a regular or exceptional past tense. Experiment 1 revealed significant latency advantages for high- over low-imageability words for both regular verbs (e.g., “ lunged” faster than “ loved”) and exception items (e.g., “ drank” faster than “ dealt”); but critically, this effect was significantly larger for exceptions than for regulars. Experiment 2 employed a semantic priming paradigm where participants inflected verb stems (e.g., sit) preceded by related (e.g., chair) or unrelated primes (e.g., jug) and revealed a priming effect in accuracy that was confined to the exception items. Our results are consistent with predictions from single-mechanism connectionist models of inflectional morphology and converge with findings from neurological patients and studies of reading aloud.
DelPhi web server v2: incorporating atomic-style geometrical figures into the computational protocol
Authors: Smith Nicholas , Witham Shawn , Sarkar Subhra , Zhang Jie , Li Lin , Li Chuan , Alexov Emil
Published: April 2012

Summary: A new edition of the DelPhi web server, DelPhi web server v2, is released to include atomic presentation of geometrical figures. These geometrical objects can be used to model nano-size objects together with real biological macromolecules. The position and size of the object can be manipulated by the user in real time until desired results are achieved. The server fixes structural defects, adds hydrogen atoms and calculates electrostatic energies and the corresponding electrostatic potential and ionic distributions.

Availability and implementation: The web server follows a client–server architecture built on PHP and HTML and utilizes DelPhi software. The computation is carried out on supercomputer cluster and results are given back to the user via http protocol, including the ability to visualize the structure and corresponding electrostatic potential via Jmol implementation. The DelPhi web server is available from http://compbio.clemson.edu/delphi_webserver.

Contact:  nsmith@clemson.edu, ealexov@clemson.edu

Supplementary information:  Supplementary data are available at Bioinformatics online.
Variability in the ICES/NAFO region between 1950 and 2009: observations from the ICES Report on Ocean Climate
Authors: Hughes Sarah L. , Holliday N. Penny , Gaillard Fabienne ,   the ICES Working Group on Oceanic Hydrography
Published: April 2012

Hughes, S. L., Holliday, N. P., Gaillard, F., and the ICES Working Group on Oceanic Hydrography, 2012. Variability in the ICES/NAFO region between 1950 and 2009: observations from the ICES Report on Ocean Climate. – ICES Journal of Marine Science, 69: 706–719. The ICES Report on Ocean Climate presents the latest information on the status and trends of sea temperature and salinity in the North Atlantic and Nordic Seas. It is the main product of the ICES Working Group on Oceanic Hydrography, published annually. Bringing together multiple time-series from across the ICES and NAFO regions offers insight into the concurrent spatial and temporal trends in ocean temperature and salinity. This paper presents an overview of the physical variability in the North Atlantic Ocean at decadal and longer time-scales and reviews the current state of understanding of the causes and mechanisms of this variability. Between the 1960s and the 1990s, the North Atlantic Oscillation (NAO) index increased from a persistent negative phase in the 1960s to a strong positive phase during the 1980s and early 1990s. However, during the decade 2000–2009, because of shifts in atmospheric pressure patterns, the NAO was weak and the NAO index was not a good indicator of atmospheric forcing. Marked changes were also observed in oceanographic indices such as the Subpolar Gyre index during the mid-1990s and, as a consequence, conditions in the decade 2000–2009 have been very different from those of the previous four decades.
Emergencies in Palliative and Supportive Care
Authors: Currow David , Clark Katherine
Published: April 2012

This is a practical, accessible guide to all emergency situations encountered in palliative care. It provides clinical guidance for the management of people with progressive life limiting illnesses including cancer, AIDS, end-stage organ failure and neurodegenerative diseases.
Preliminary Assessment of Resistance Among U.S. Wheat Cultivars to the Triticum Pathotype of Magnaporthe oryzae
Authors: Cruz Christian D. , Bockus William W. , Stack James P. , Tang Xiaoyan , Valent Barbara , Pedley Kerry F. , Peterson Gary L.
Published: April 2012

Magnaporthe oryzae is the causal agent of blast disease on several graminaceous plants. The M. oryzae population causing wheat blast has not been officially reported outside South America. Wheat production in the United States is at risk to this pathogen if it is introduced and established. Proactive testing of U.S. wheat cultivars for their reaction to blast and identification of resistance resources is crucial due to the national and global importance of the U.S. wheat industry. In this preliminary study, the phenotypic reaction of 85 U.S. wheat cultivars to M. oryzae (Triticum pathotype) was determined. Although there was a significant correlation in the reaction to blast at the seedling and adult plant stages, only 57% of the head reaction was explained by the seedling reaction. Because of the importance of disease development at the head stage in the field, assessment of all 85 cultivars occurred at the head stage. Among cultivars tested, a continuum in severity to head blast was observed; cultivars Everest and Karl 92 were highly susceptible with more than 90% disease severity, while cultivars Postrock, JackPot, Overley, Jagalene, Jagger, and Santa Fe showed less than 3% infection. No evidence of the presence of physiological races among isolates T-7, T-12, T-22, and T-25 was found.
In Vitro Kinetic Evaluation of the Free Radical Scavenging Ability of Propofol
Authors: Li Weiguang , Zhang Yu , Liu Yanru , Yue Feng , Lu Yiming , Qiu Huanrong , Gao Dawen , Gao Yan , Wu Yonghong , Wang Zhaoyan , Huang Rongqing , Zhang Chenggang
Published: April 2012

Background

Propofol is a widely used, short-acting, and intravenously administered hypnotic agent with notable antioxidant and free radical scavenging activities. However, there are relatively few kinetic studies on the free radical scavenging ability of propofol. The goal of this study is to evaluate the kinetics of propofol scavenging 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical (ABTS(·+)).

Methods

The stock solution of ABTS(·+) was prepared by incubating 7 mM ABTS with 2.8 mM potassium persulfate in deionized water, and then diluted with 5 mM phosphate-buffered saline (pH 7.2) to get a working solution (36 μM ABTS(·+) and 18 μM ABTS). The reaction was monitored by measuring specific absorbance changes of ABTS and ABTS(·+) after adding 4 μM propofol (final concentration) to the working solution. The propofol-ABTS(·+) reaction products were analyzed by high-performance liquid chromatography and liquid chromatography mass spectrometry/mass spectrometry.

Results

Wave scanning and kinetic evaluation demonstrated that the ABTS(·+) scavenging process of propofol is relatively fast. The ABTS(·+) consumption rate by propofol is greater than the rate of ABTS formation. The degradation products of reaction between propofol and ABTS(·+) were mainly ABTS-propofol, a part of the ABTS molecule, and a combination of propofol with a part of the ABTS molecule.

Conclusions

Propofol scavenges ABTS(·+) with a fast and stable kinetic feature in vitro, which is useful and important for understanding propofol's antioxidant properties. The kinetic process of the free radical scavenging activity of propofol may also play a role in dynamic protection in the body.
Clinical Significance of Eosinophilia and Chronic Inflammatory Infiltrate in Children's Rectal Biopsies
Authors: Pacilli Maurizio , Eaton Simon , Clarke Alessandra , Whitehead Anita , Nagy Anita , Brain Jeffrey L.
Published: April 2012

Aims:

The aim of the present study was to determine the clinical significance of an incidental finding of eosinophilia (EOS) and chronic inflammatory infiltrate (CINF) in rectal biopsies of children investigated for suspected Hirschsprung disease (HSCR).

Methods:

A retrospective study (2000–2010) of children incidentally found to have EOS and CINF was performed. HSCR cases were excluded. Presence of gastrointestinal (GI) symptoms and nutritional status (weight‐for‐age z score) were investigated and compared with a matched cohort with normal biopsy.

Results:

Of 364 children undergoing rectal biopsy for suspected HSCR, 109 had confirmed HSCR, whereas 255 children had normal ganglia. Forty‐four of 255 (17%) children had EOS and/or CINF incidentally reported and are the subject of the present study. In 13 of 44 (29%) children, the biopsy was performed neonatally. At follow‐up (4.6 months [1–22]), 21 (48%) had food and/or milk allergy, 30 (68%) had constipation and/or other GI symptoms. There was no change in weight‐for‐age z score (P = 0.85) at follow‐up and 8 (20%) had failure to thrive. Only 10 of 44 (P = 0.0001 vs patients with EOS and/or CINF) children with normal biopsy had persistent constipation at follow‐up (9.7 months [0.5–84.7]) and 1 patient had atopy. Patients with normal biopsy exhibited an increase in weight‐for‐age z score at follow‐up (P = 0.003) and only 3 patients (7%) had failure to thrive.

Conclusions:

EOS and CINF are found in 17% of children who had rectal biopsies negative for HSCR. Half of these children will need further medical input for the presence of persisting GI symptoms, food/milk allergy and failure to thrive, and the possibility to develop inflammatory bowel disease later in life.