bluuebunny/crossref_metadata_2025 huggingface dataset:
Surface differential rotation of IL Hya from time-series Doppler images
Authors: Kővári Zsolt , Kriskovics Levente , Oláh Katalin , Vida Krisztián , Bartus János , Strassmeier Klaus G. , Weber Michael
Published: August 2014

We present a time-series Doppler imaging study of the K-subgiant component in the RS CVn-type binary system IL Hya (Porb=12.905 d). From re-processing the unique long-term spectroscopic dataset of 70 days taken in 1996/97, we perform a thorough cross-correlation analysis to derive surface differential rotation. As a result we get solar-type differential rotation with a shear value α of 0.05, in agreement with preliminary suggestions from previous attempts. A possible surface pattern of meridional circulation is also detected.
Hydromagnetic Equilibria and their Evolution in Neutron Stars
Authors: Reisenegger Andreas
Published: August 2014

The strongest known magnetic fields are found in neutron stars. I briefly discuss how they are inferred from observations, as well as the evidence for their time-evolution. I go on to show how these extremely strong fields are actually weak in terms of their effects on the stellar structure. This is also the case for magnetic stars on the upper main sequence and magnetic white dwarfs, which have similar total magnetic fluxes, perhaps pointing to an evolutionary connection. I suggest that a stable hydromagnetic equilibrium (containing a poloidal and a toroidal field component) could be established soon after the birth of the neutron star, aided by the strong compositional stratification of neutron star matter, and this state is slowly eroded by non-ideal magnetohydrodynamic processes such as beta decays and ambipolar diffusion in the core of the star and Hall drift and breaking of the solid in its crust. Over sufficiently long time scales, the fluid in the neutron star core will behave as if it were barotropic, because, depending on temperature and magnetic field strength, beta decays will keep adjusting the composition to the chemical equilibrium state, or ambipolar diffusion will decouple the charged component from the neutrons. Therefore, the still open question regarding stable hydromagnetic equilibria in barotropic fluids will become relevant for the evolution, at least for magnetar fields, which are likely too strong to be stabilized by the solid crust.
Economic expectations and support for secession in Catalonia: between causality and rationalization
Authors: Muñoz Jordi , Tormos Raül
Published: August 2014

Support for independence from Spain has sharply increased in recent years in Catalonia. According to all available evidence, public opinion has shifted from an overwhelmingly pro-autonomy position to an increasingly pro-independence stance. How can we explain such widespread support for secession in a democratic context? Traditionally, national identity has been regarded as the main explanatory factor, but recent accounts tend to underline the effect of political elite’s agency as well as instrumental calculations regarding the economic consequences of secession. However, the identification of this last causal effect is subject to a fundamental challenge: the possibility that economic expectations are mere rationalizations of prior preferences. In order to overcome this identification problem, we combine the analysis of observational survey data with an original survey-embedded experiment that provides a robust test of the causal nature of economic expectations. Our results show how identity, as well as partisanship, are the main drivers of support for secession, but also that economic considerations play an independent role. Results show that economic motivations are more relevant for citizens with ambivalent identity positions and for those that have no party identification, or are partisans of parties with less clear-cut stances on the issue.
Spatio-temporal processing of tactile stimuli in autistic children
Authors: Wada Makoto , Suzuki Mayuko , Takaki Akiko , Miyao Masutomo , Spence Charles , Kansaku Kenji
Published: August 2014

Altered multisensory integration has been reported in autism; however, little is known concerning how the autistic brain processes spatio-temporal information concerning tactile stimuli. We report a study in which a crossed-hands illusion was investigated in autistic children. Neurotypical individuals often experience a subjective reversal of temporal order judgments when their hands are stimulated while crossed and the illusion is known to be acquired in early childhood. However, under those conditions where the somatotopic representation is given priority over the actual spatial location of the hands, such reversals may not occur. Here, we showed that a significantly smaller illusory reversal was demonstrated in autistic children than in neurotypical children. Furthermore, in an additional experiment, the young boys who had higher Autism Spectrum Quotient (AQ) scores generally showed a smaller crossed hands deficit. These results suggest that rudimentary spatio-temporal processing of tactile stimuli exists in autistic children and the altered processing may interfere with the development of an external frame of reference in real-life situations.
Surface engineering of synthetic polymer materials for tissue engineering and regenerative medicine applications
Authors: Rashidi Hassan , Yang Jing , Shakesheff Kevin M.
Published: August 2014

When using polymer materials as scaffolds for tissue engineering or regenerative medicine applications the initial, and often lasting, interaction between cells and the material areviasurfaces.
Evolutionary game theory: molecules as players
Authors: Bohl Katrin , Hummert Sabine , Werner Sarah , Basanta David , Deutsch Andreas , Schuster Stefan , Theißen Günter , Schroeter Anja
Published: August 2014

In many situations macromolecules, such as proteins, DNA and RNA, can be considered as players in the sense of game theory. In this review we discuss the usefulness of game theory in describing macromolecular processes.
A novel ratiometric fluorescence sensor for Zn2+detection
Authors: Gu Liqiang , Wan Xuejuan , Liu Haiyang , Liu Tianqi , Yao Youwei
Published: August 2014

We report a ratiometric probe with 8-aminoquinoline as the fluorophore and salicylhydrazide group as the receptor, which shows low detection limit for Zn2+, as well as anti-interference towards Cd2+and Pb2+.
Dual-stage growth factor release within 3D protein-engineered hydrogel niches promotes adipogenesis
Authors: Greenwood-Goodwin Midori , Teasley Eric S. , Heilshorn Sarah C.
Published: August 2014

We developed a strategy for dual-stage delivery of fibroblast growth factor 1 (FGF-1) and bone morphogenetic protein 4 (BMP-4) within 3D biomimetic hydrogels to promote adipogenesis of human adipose-derived stromal cells.
Aqueous stabilisation of carbon-encapsulated superparamagnetic α-iron nanoparticles for biomedical applications
Authors: Aguiló-Aguayo Noemí , Maurizi Lionel , Galmarini Sandra , Ollivier-Beuzelin Marie Gabrielle , Coullerez Géraldine , Bertran Enric , Hofmann Heinrich
Published: August 2014

Carbon-encapsulated superparamagnetic α-Fe nanoparticles were stabilised in aqueous media allowing their cell internalisation.
Organic photoelectrochemical cells with quantitative photocarrier conversion
Authors: Guerrero Antonio , Haro Marta , Bellani Sebastiano , Antognazza Maria Rosa , Meda Laura , Gimenez Sixto , Bisquert Juan
Published: August 2014

Efficient solar-to-fuel conversion could be a cost-effective way to power the planet using sunlight.
Charged particle-induced synthesis of carbon nanowalls and characterization
Authors: Uchida Takashi , Baliyan Ankur , Fukuda Takahiro , Nakajima Yoshikata , Yoshida Yoshikazu
Published: August 2014

High deposition rate, control of domain size, detailed characterization and charged particle-induced growth mechanism of CNW films are reported.
Synthesis of high performance Li4Ti5O12 microspheres and TiO2 nanowires from natural ilmenite
Authors: Wu Feixiang , Wang Zhixing , Li Xinhai , Guo Huajun
Published: August 2014

In this work, natural ilmenite is transformed into either Li4Ti5O12 microspheres or TiO2 nanowires through a series of chemical and thermal processes by the combination of metallurgy and materials science. Both of the synthesized materials demonstrate excellent electrochemical performance.
Simultaneous adsorption of nitrogenous heterocyclic compounds by granular activated carbon: parameter optimization and multicomponent isotherm modeling
Authors: Hiwarkar Ajay Devidas , Chandra Srivastava Vimal , Mall Indra Deo
Published: August 2014

Granular activated carbon used for simultaneous adsorption of pyrrole and indole from aqueous solution.
Soap film vibration: origin of the dissipation
Authors: Acharige Sébastien Kosgodagan , Elias Florence , Derec Caroline
Published: August 2014

When a soap film is vibrated (antisymmetric mode), the wave attenuation is dominated by the viscous dissipation in surrounding air.
Multi-modal delivery of therapeutics using biomaterial scaffolds
Authors: Browne S. , Pandit A.
Published: August 2014

Functionalisation of biomaterials with therapeutic moieties (proteins, drugs, genes) is a pre-requisite to tissue regeneration and restoration of function following injury or disease.
N-Ethyl-N-nitrosourea-induced transplacental lung tumor development and its control: molecular modulations for tumor susceptibility in a mouse model
Authors: Sahay Satya , Upadhyay Daya S. , Gupta Krishna P.
Published: August 2014

The development of lung tumors after transplacentalN-ethyl-N-nitrosourea (ENU) exposure has been demonstrated in Swiss and Balb/c mice F1 mice.
Doing What Works: A Discussion of Medical Futility
Authors: Leslie Paula , Rourke Nancy , Sacks Tamara
Published: August 2014

Historically speech-language pathologists (SLPs) were a “fix-it”-focused rehabilitation profession. In recent years we have been drawn into decisions that are more challenging. Our profession has an increasing awareness of the complexity and subtleness required in decision making. How do other professions grapple with this complexity and in particular the concept of the “futility” of medical intervention? Perhaps the two of the most closely allied disciplines in this area are bioethics and medicine and I invited two colleagues to consider this topic with me. Dr. Nancy Rourke is a bioethicist with experience in Catholic and philosophical ethics, long-term care and end-of-life health care ethics. Dr. Tamara Sacks is a physician with experience in internal medicine, palliative care and hospice. We encourage the reader to step beyond the confines of the historically rehabilitation focused profession in order to gain understanding that will benefit our patients and families.
Face recognition using sparse feature sphere centroid classifier
Authors: Feng Qingxiang , Pan Jeng‐Shyang , Lee Ivan
Published: August 2014

The sparse feature sphere centroid (SFSC) classifier for face recognition is proposed. SFSC is based on nearest feature plane (NFP), sparse representation classification (SRC) and nearest feature centres (NFC), and it contains two stages. In the first stage, the SFSC classifier computes the feature sphere centroid metric. Then, SFSC obtains the sparse coefficients by solving an L1‐norm minimisation problem and uses the sparse coefficients to calculate the weighted feature sphere centroid distance, which will be utilised for classification. Experiments on the Georgia Tech (GT) face database and AR face database were conducted to evaluate the proposed classifier. The experimental results show that the proposed classifier yields better recognition rate over competing classifiers such as NFC, NFP and SRC.
Development of fatigue stress spectrum and fatigue life prediction of endless winder sheave for wind turbine lift using finite element analysis
Authors: Woong Choi Chan , Pyo Lee Seung , Weon Kang Ki
Published: August 2014

This paper aims to develop the fatigue stress spectrum and predicted fatigue life of the endless winder sheave using finite element (FE) analysis, which is utilized in wind turbine lift. First, we identified the fatigue critical location (FCL) of endless winder sheave through a static FE analysis. And the lifting velocity was measured using the non-contact velocity dectector. Based on the measured lifting velocity and compressive loads by traction of endless winder sheave, the compressive load-angle of rotation history at the FCL was determined. According to the compressive load-angle of rotation time history, total 230 FE analyses were performed with the interval of the angle of rotation of 15°, we eventually obtained the fatigue stress spectrum at the FCL. These results were processed using the rainflow cycle counting and the Goodman equation. Finally, the fatigue life of sheave was evaluated using the linear damage cumulative rule.
Quantization of systems with temporally varying discretization. I. Evolving Hilbert spaces
Authors: Höhn Philipp A.
Published: August 2014

A temporally varying discretization often features in discrete gravitational systems and appears in lattice field theory models subject to a coarse graining or refining dynamics. To better understand such discretization changing dynamics in the quantum theory, an according formalism for constrained variational discrete systems is constructed. While this paper focuses on global evolution moves and, for simplicity, restricts to flat configuration spaces \documentclass[12pt]{minimal}\begin{document}$\mathbb {R}^N$\end{document}RN, a Paper II [P. A. Höhn, “Quantization of systems with temporally varying discretization. II. Local evolution moves,” J. Math. Phys., e-print arXiv:1401.7731 [gr-qc].] discusses local evolution moves. In order to link the covariant and canonical picture, the dynamics of the quantum states is generated by propagators which satisfy the canonical constraints and are constructed using the action and group averaging projectors. This projector formalism offers a systematic method for tracing and regularizing divergences in the resulting state sums. Non-trivial coarse graining evolution moves lead to non-unitary, and thus irreversible, projections of physical Hilbert spaces and Dirac observables such that these concepts become evolution move dependent on temporally varying discretizations. The formalism is illustrated in a toy model mimicking a “creation from nothing.” Subtleties arising when applying such a formalism to quantum gravity models are discussed.
Quantum error correcting codes and 4-dimensional arithmetic hyperbolic manifolds
Authors: Guth Larry , Lubotzky Alexander
Published: August 2014

Using 4-dimensional arithmetic hyperbolic manifolds, we construct some new homological quantum error correcting codes. They are low density parity check codes with linear rate and distance nε. Their rate is evaluated via Euler characteristic arguments and their distance using \documentclass[12pt]{minimal}\begin{document}$\mathbb {Z}_2$\end{document}Z2-systolic geometry. This construction answers a question of Zémor [“On Cayley graphs, surface codes, and the limits of homological coding for quantum error correction,” in Proceedings of Second International Workshop on Coding and Cryptology (IWCC), Lecture Notes in Computer Science Vol. 5557 (2009), pp. 259–273], who asked whether homological codes with such parameters could exist at all.
Initial surface disturbance on a shear current: The Cauchy-Poisson problem with a twist
Authors: Ellingsen Simen Å.
Published: August 2014

We solve for the first time the classical linear Cauchy-Poisson problem—the time evolution of an initial surface disturbance—when a shear current of uniform vorticity is present beneath the surface. The solution is general, including the effects of gravity, surface tension, and constant finite depth. The particular case of an initially Gaussian disturbance of width b is studied for different values of three system parameters: a “shear Froude number” \documentclass[12pt]{minimal}\begin{document}$S\sqrt{b/g}$\end{document}Sb/g (S is the vorticity), the Bond number and the depth relative to the initial perturbation width. Different phase and group velocity in different directions yield very different wave patterns in different parameter regimes when the shear is strong, and the well-known pattern of diverging ring waves in the absence of shear can take on very different qualitative behaviours. For a given shear Froude number, both finite depth and nonzero capillary effects are found to weaken the influence of the shear on the resulting wave pattern. The various patterns are analysed and explained in light of the shear-modified dispersion relation.
Low-energy dc ion source for low operating pressure
Authors: Oks Efim , Shandrikov Maxim , Salvadori Cecilia , Brown Ian
Published: August 2014

We report on an experimental study of an ion source based on a Penning discharge with a cold hollow cathode in crossed electric and magnetic fields. The minimum vacuum chamber operating pressure was 3 × 10−5 Torr for argon and 5 × 10−5 Torr for hydrogen. The use of a hollow cathode allowed decreasing the discharge operating voltage down to 350 V at a discharge current of ∼100 mA. At a discharge current of 100 mA and beam accelerating voltage of 2 kV, the ion current was 2.5 mA for argon and 8 mA for hydrogen, and the ion beam on-axis current density 170 and 450 μA/cm2, respectively. The current-voltage characteristics of the discharge and the radial ion beam current density distribution were measured. The influence of pressure on the discharge parameters and their time stability was investigated.
Ion acoustic solitons and supersolitons in a magnetized plasma with nonthermal hot electrons and Boltzmann cool electrons
Authors: Rufai O. R. , Bharuthram R. , Singh S. V. , Lakhina G. S.
Published: August 2014

Arbitrary amplitude, ion acoustic solitons, and supersolitons are studied in a magnetized plasma with two distinct groups of electrons at different temperatures. The plasma consists of a cold ion fluid, cool Boltzmann electrons, and nonthermal energetic hot electrons. Using the Sagdeev pseudo-potential technique, the effect of nonthermal hot electrons on soliton structures with other plasma parameters is studied. Our numerical computation shows that negative potential ion-acoustic solitons and double layers can exist both in the subsonic and supersonic Mach number regimes, unlike the case of an unmagnetized plasma where they can only exist in the supersonic Mach number regime. For the first time, it is reported here that in addition to solitions and double layers, the ion-acoustic supersoliton solutions are also obtained for certain range of parameters in a magnetized three-component plasma model. The results show good agreement with Viking satellite observations of the solitary structures with density depletions in the auroral region of the Earth's magnetosphere.
Analysis of the multipactor effect in circular waveguides excited by two orthogonal polarization waves
Authors: Pérez A. M. , Gimeno B. , Boria V. E. , Anza S. , Vicente C. , Gil J.
Published: August 2014

Circular waveguides, either employed as resonant cavities or as irises connecting adjacent guides, are widely present in many passive components used in different applications (i.e., particle accelerators and satellite subsystems). In this paper, we present the study of the multipactor effect in circular waveguides considering the coexistence of the two polarizations of the fundamental TE11 circular waveguide mode. For a better understanding of the problem, only low multipactor orders have been explored as a function of the polarization ellipse eccentricity. Special attention has been paid to the linear and circular polarizations, but other more general configurations have also been explored.
Collision-dependent power law scalings in two dimensional gyrokinetic turbulence
Authors: Cerri S. S. , Bañón Navarro A. , Jenko F. , Told D.
Published: August 2014

Nonlinear gyrokinetics provides a suitable framework to describe short-wavelength turbulence in magnetized laboratory and astrophysical plasmas. In the electrostatic limit, this system is known to exhibit a free energy cascade towards small scales in (perpendicular) real and/or velocity space. The dissipation of free energy is always due to collisions (no matter how weak the collisionality), but may be spread out across a wide range of scales. Here, we focus on freely decaying two dimensional electrostatic turbulence on sub-ion-gyroradius scales. An existing scaling theory for the turbulent cascade in the weakly collisional limit is generalized to the moderately collisional regime. In this context, non-universal power law scalings due to multiscale dissipation are predicted, and this prediction is confirmed by means of direct numerical simulations.
Non-perturbative analysis of space charge limited electron flow in critical regimes
Authors: Rokhlenko A. , Lebowitz J. L.
Published: August 2014

The combined Eulerian-Lagrangian formalism, developed in our previous work for studying the turn on regime of a one-dimensional diode, is extended for wider versatility and better precision in the study of the time dependent space charge limited electron flow with fixed injected current. An analytical analysis is supplemented with an approximate numerical scheme which appears to be sufficiently accurate to calculate the flow evolution until the process approaches stabilization or becomes unstable. This can be compared with properties of stationary flows and showed to be in a good agreement with them. When the stabilization is impossible, the ratio of anode to cathode currents is decreasing and thus the space charge is accumulated in the diode. We discuss the limitations of our approach and give some qualitative estimates for the flow parameters when stabilization is impossible.
Superconducting properties in tantalum decorated three-dimensional graphene and carbon structures
Authors: Cobaleda Cayetano S. F. , Xiao Xiaoyin , Burckel D. Bruce , Polsky Ronen , Huang Duanni , Diez Enrique , Pan W.
Published: August 2014

We present here the results on superconducting properties in tantalum thin films (100 nm thick) deposited on three-dimensional graphene (3DG) and carbon structures. A superconducting transition is observed in both composite thin films with a superconducting transition temperature of 1.2 K and 1.0 K, respectively. We have further measured the magnetoresistance at various temperatures and differential resistance dV/dI at different magnetic fields in these two composite thin films. In both samples, a much large critical magnetic field (∼2 T) is observed and this critical magnetic field shows linear temperature dependence. Finally, an anomalously large cooling effect was observed in the differential resistance measurements in our 3DG-tantalum device when the sample turns superconducting. Our results may have important implications in flexible superconducting electronic device applications.
Capricornia Allied Health Partnership (CAHP): a case study of an innovative model of care addressing chronic disease through a regional student-assisted clinic
Authors: Frakes Kerrie-anne , Brownie Sharon , Davies Lauren , Thomas Janelle B. , Miller Mary-Ellen , Tyack Zephanie
Published: August 2014

Faced with significant health and workforce challenges, the Central Queensland Hospital and Health Service commenced an innovative student-assisted clinical model of care ‐ The Capricornia Allied Health Partnership (CAHP) in 2010. The clinic supports pre-entry allied health student clinical placements to: (1) address service delivery gaps for previously underserved people with chronic disease; (2) facilitate hospital avoidance and early discharge from the local hospital; (3) provide an attractive clinical placement opportunity for allied health students that will potentially lead to future recruitment success, and (4) demonstrate leadership in developing interprofessional skills of future health workforce trainees. This case study details the conceptual background of the initial model, the key features of the clinical placement and service delivery model, and discusses the current and future evaluation of the clinic.
DRK/DOS/SOS converge with Crk/Mbc/dCed-12 to activate Rac1 during glial engulfment of axonal debris
Authors: Lu Tsai-Yi , Doherty Johnna , Freeman Marc R.
Published: August 2014

Significance

Neuronal cell death or injury leads to the production of neuronal cell corpses and cellular debris that must be cleared from the nervous system to avoid inflammation or toxicity. Glia are the primary cell type responsible for clearing neuronal debris, but precisely how these cells recognize, phagocytose, and destroy this material remains poorly defined. Here we use a simple nerve injury assay to identify genes downstream of the engulfment receptor Draper that are required for efficient glial engulfment of degenerating axons. Based on the molecular and functional conservation of this pathway in mammals, this study sheds new light on pathways potentially used by mammalian glia to react to brain injury or neurodegeneration.
An Egg-Per-Recruit Model to Evaluate the Effects of Upstream Transport and Downstream Passage Mortality of American Eel in the Susquehanna River
Authors: Sweka John A. , Eyler Sheila , Millard Michael J.
Published: August 2014

Dams and their associated effects on the migration and mortality of the American Eel Anguilla rostrata have been implicated as a significant factor in the current depleted status of the species along the Atlantic coast of North America. Female American Eels that mature in areas below dams may be smaller and have lower fecundity than individuals that mature in more upstream reaches of a river system. However, increased mortality associated with downstream migration through hydroelectric turbines may negate any reproductive advantage afforded to American Eels occupying areas upstream of hydroelectric facilities. We developed an American Eel egg-per-recruit (EPR) model to investigate how various levels of upstream and downstream passage may affect the reproductive output from rivers with hydroelectric facilities. We applied our model to the Susquehanna River and found that if American Eels are passed upstream of multiple dams on the river, cumulative downstream passage survival must be ≥33% for the upstream passage to be beneficial; otherwise, upstream passage is likely to result in an EPR deficit when compared with no passage. Cumulative downstream passage survival would need to increase substantially above 33% to have a high probability of making any gains in terms of EPR. Our EPR modeling framework can be adapted to other systems and used to make recommendations for necessary upstream and downstream passage for the conservation of American Eels in rivers impacted by hydroelectric facilities.

Received December 24, 2013; accepted March 28, 2014
Characterization of River Herring Bycatch in the Northwest Atlantic Midwater Trawl Fisheries
Authors: Bethoney N. David , Stokesbury Kevin D. E. , Schondelmeier Bradley P. , Hoffman William S. , Armstrong Michael P.
Published: August 2014

In the U.S. northwest Atlantic, the incidental catch of river herring (Alewife Alosa pseudoharengus and Blueback Herring A. aestivalis) by midwater trawl vessels targeting Atlantic Herring Clupea harengus and Atlantic Mackerel Scomber scombrus has become a concern for river herring conservation. Reduction of this incidental catch is a focus of fisheries managers, but information about river herring bycatch is limited. To improve the information available to fishery managers, we combined portside and at-sea observations to examine (1) the size of river herring, (2) the concentration of river herring with respect to the target species, and (3) the yearly contribution of different fishery areas to the total catch of river herring. We divided the fishery's spatial range into four nearshore areas and tested two null hypotheses: (1) length frequency distributions of river herring are similar between areas and between species and (2) bycatch ratios are similar among areas. We also used length frequency distributions and river herring size at maturity to infer and compare maturity status. Results showed interannual, interspecies, and intraspecies differences in bycatch among and within the four nearshore areas. Bycatch in the northern areas was mainly migratory mature or near-mature river herring from mixed origins, whereas bycatch in the southern areas was a mix of juveniles, prespawning adults from nearby areas, and migratory adults. At the levels seen in 2011 and 2012, bycatch in the midwater trawl fishery could not account for the overall decline in river herring. However, a large proportion of river herring caught in the southern areas of the fishery may be juveniles originating from New Jersey to southern New England. To better understand this impact, continued monitoring and studies examining the at-sea population dynamics of river herring are needed.

Received June 4, 2013; accepted April 2, 2014
Splitting vector bundles outside the stable range and 𝔸¹-homotopy sheaves of punctured affine spaces
Authors: Asok Aravind , Fasel Jean
Published: August 2014

We discuss the relationship between theA1{\mathbb A}^1-homotopy sheaves ofAn∖0{\mathbb A}^n {\setminus } 0and the problem of splitting off a trivial rank11summand from a ranknnvector bundle. We begin by computingπ3A1(A3∖0)\boldsymbol {\pi }_3^{{\mathbb A}^1}({\mathbb A}^3 {\setminus } 0)and providing a host of related computations of “non-stable”A1{\mathbb A}^1-homotopy sheaves. We then use our computation to deduce that a rank33vector bundle on a smooth affine44-fold over an algebraically closed field having characteristic unequal to22splits off a trivial rank11summand if and only if its third Chern class (in Chow theory) is trivial. This result provides a positive answer to a case of a conjecture of M.P. Murthy.
Estimating biological elementary flux modes that decompose a flux distribution by the minimal branching property
Authors: Chan Siu Hung Joshua , Solem Christian , Jensen Peter Ruhdal , Ji Ping
Published: August 2014

Motivation: Elementary flux mode (EFM) is a useful tool in constraint-based modeling of metabolic networks. The property that every flux distribution can be decomposed as a weighted sum of EFMs allows certain applications of EFMs to studying flux distributions. The existence of biologically infeasible EFMs and the non-uniqueness of the decomposition, however, undermine the applicability of such methods. Efforts have been made to find biologically feasible EFMs by incorporating information from transcriptional regulation and thermodynamics. Yet, no attempt has been made to distinguish biologically feasible EFMs by considering their graphical properties. A previous study on the transcriptional regulation of metabolic genes found that distinct branches at a branch point metabolite usually belong to distinct metabolic pathways. This suggests an intuitive property of biologically feasible EFMs, i.e. minimal branching.

Results: We developed the concept of minimal branching EFM and derived the minimal branching decomposition (MBD) to decompose flux distributions. Testing in the core Escherichia coli metabolic network indicated that MBD can distinguish branches at branch points and greatly reduced the solution space in which the decomposition is often unique. An experimental flux distribution from a previous study on mouse cardiomyocyte was decomposed using MBD. Comparison with decomposition by a minimum number of EFMs showed that MBD found EFMs more consistent with established biological knowledge, which facilitates interpretation. Comparison of the methods applied to a complex flux distribution in Lactococcus lactis similarly showed the advantages of MBD. The minimal branching EFM concept underlying MBD should be useful in other applications.

Contact:  sinhu@bio.dtu.dk or p.ji@polyu.edu.hk

Supplementary information:  Supplementary data are available at Bioinformatics online.
Torsional behavior of chromatin is modulated by rotational phasing of nucleosomes
Authors: Nam Gi-Moon , Arya Gaurav
Published: August 2014

Torsionally stressed DNA plays a critical role in genome organization and regulation. While the effects of torsional stresses on naked DNA have been well studied, little is known about how these stresses propagate within chromatin and affect its organization. Here we investigate the torsional behavior of nucleosome arrays by means of Brownian dynamics simulations of a coarse-grained model of chromatin. Our simulations reveal a strong dependence of the torsional response on the rotational phase angle Ψ0 between adjacent nucleosomes. Extreme values of Ψ0 lead to asymmetric, bell-shaped extension-rotation profiles with sharp maxima shifted toward positive or negative rotations, depending on the sign of Ψ0, and to fast, irregular propagation of DNA twist. In contrast, moderate Ψ0 yield more symmetric profiles with broad maxima and slow, uniform propagation of twist. The observed behavior is shown to arise from an interplay between nucleosomal transitions into states with crossed and open linker DNAs and global supercoiling of arrays into left- and right-handed coils, where Ψ0 serves to modulate the energy landscape of nucleosomal states. Our results also explain the torsional resilience of chromatin, reconcile differences between experimentally measured extension-rotation profiles, and suggest a role of torsional stresses in regulating chromatin assembly and organization.
Sensitivity of Alternaria alternata from Citrus to Boscalid and Polymorphism in Iron-Sulfur and in Anchored Membrane Subunits of Succinate Dehydrogenase
Authors: Vega Byron , Dewdney Megan M.
Published: August 2014

Boscalid, a succinate dehydrogenase inhibitor (SDHI), was registered in 2011 to control Alternaria brown spot (ABS) of citrus, caused by Alternaria alternata. In this study, the effect of boscalid on mycelial growth, conidial germination, and resazurin reduction was established in a subset of 16 sensitive isolates using three different media. Conidial germination and mycelial growth inhibition were not suppressed even at higher concentrations of boscalid, although effective concentration to inhibit 50% growth (EC50) values were established with each method. Resazurin reduction produced the lowest EC50 values and was selected for further sensitivity tests. In total, 419 isolates, never exposed to boscalid and collected from Florida tangerine orchards between 1996 to 2012, were tested for boscalid sensitivity. The sensitivity distribution was a unimodal curve with a mean EC50 value of 0.60 μg/ml and a range of 0.07 to 5.84 μg/ml. The molecular characterization of the succinate dehydrogenase (SDH) genes were also determined in a subset of 15 isolates, exhibiting great variability in boscalid sensitivity, by cloning and sequencing the sdhB, sdhC, and sdhD genes. Sequence comparisons of the SDH complex revealed the presence of mutations in 14 of 15 isolates. In total, 21 mutations were identified. Double and multiple mutations were observed in SDHC and SDHD, respectively. In SDHB, 4 mutations were observed while, in SDHC and SDHD, 5 and 12 mutations were detected, respectively. No mutations were found in the highly conserved histidine residues at positions 277 in SDHB, 134 in SDHC, and 133 in SDHD, typically observed in SDHI-resistant isolates. Our findings suggest that A. alternata populations from Florida are sensitive to boscalid and it could be used in ABS spray programs. Boscalid resistance is currently not a problem, although further monitoring for resistance is advisable.
First Report of Downy Mildew on Blackberry Caused by Peronospora sparsa in Arkansas
Authors: Smith S. , Roberson S. , Cochran K.
Published: August 2014

In March of 2014, blackberry (Rubus fruticosus) greenhouse seedlings with leaf symptoms that included yellowing on the leaf surface and reddish brown angular lesions with necrotic centers and chlorotic margins were detected in the University of Arkansas Fruit Research Station in Clarksville, AR (35°32.065′ N, 93°24.3564′ W). Symptoms were observed on multiple blackberries in the greenhouse, with an estimated prevalence of 25%. Three symptomatic samples of the affected plants were submitted to the Plant Health Clinic in Fayetteville, AR, for diagnosis. Sporulation was observed on the underside of the symptomatic leaf tissue. Hyaline sporangiophores were observed emerging from stomata on the undersides of leaves, 295 to 620 × 4 to 6 μm with long, straight trunks and were branched 3 to 4 times with bifurcated tips, with a length of 5 to 23 μm. Typically, one branch of each pair curved inward and one reflexed. Sporangiophores ended with sporangia that were round or slightly ovoid, colorless to yellowish-brown, and 14 to 22 × 11 to 18 μm. The causal agent was morphologically identified as Peronospora sparsa Berk (1,2). The identification was confirmed using a molecular method directly from plant tissue. DNA was extracted from two samples (~3 × 3 mm) from each of three symptomatic leaves, followed by PCR amplification using P. sparsa-specific rDNA-ITS region primers P1: 5′-CACGTGAACCGTATCAACC-3′ and P2: 5′-GATAGGGCTTGCCCAGTAG-3′ (GenBank Accession No. Y15816) (4). DNA amplification was successful, resulting in a product of 94 bp, confirming that P. sparsa was present in the symptomatic blackberry tissue. Sporulating leaf tissue was laid on the underside of surface sterilized blackberry leaves from three plants with a similar genetic background and incubated at 17°C with a 12-h photoperiod in a moist chamber. Sporangiophores and sporangia developed on the underside of lesions on previously uninfected leaves 16 days after inoculation. As a control, leaves from the same three plants were surface sterilized and placed in a moist chamber and incubated at 17°C with a 12-h photoperiod and examined 16 days later. No lesions or sporulation developed on the controls. Previously, P. sparsa has been reported on blackberry in California (3) and Mexico (5). To our knowledge, this is the first report of P. sparsa causing downy mildew on blackberry in Arkansas.

References: (1) M. J. Berkeley. Gardeners' Chronicle 14:307, 1861. (2) M. A. Ellis. Page 15 in: Compendium of Raspberry and Blackberry Diseases and Insects. APS Press, St. Paul, MN, 1989. (3) D. Farr et al. Page 486 in: Fungi on Plants and Plant Products in the United States. APS Press, St. Paul, MN, 1989. (4) A. Hukkanen et al. Eur. J. Plant Pathol. 116:225, 2006. (5) A. Rebollar-Alviter et al. Plant Dis. 93:674, 2009.
Epidemic cycles driven by host behaviour
Authors: Althouse Benjamin M. , Hébert-Dufresne Laurent
Published: August 2014

Host immunity and demographics (the recruitment of susceptibles via birthrate) have been demonstrated to be a key determinant of the periodicity of measles, pertussis and dengue epidemics. However, not all epidemic cycles are from pathogens inducing sterilizing immunity or are driven by demographics. Many sexually transmitted infections are driven by sexual behaviour. We present a mathematical model of disease transmission where individuals can disconnect and reconnect depending on the infectious status of their contacts. We fit the model to historic syphilis (
Treponema pallidum
) and gonorrhea (
Neisseria gonorrhoeae
) incidence in the USA and explore potential intervention strategies against syphilis. We find that cycles in syphilis incidence can be driven solely by changing sexual behaviour in structured populations. Our model also explains the lack of similar cycles in gonorrhea incidence even if the two infections share the same propagation pathways. Our model similarly illustrates how sudden epidemic outbreaks can occur on time scales smaller than the characteristic demographic time scale of the population and that weaker infections can lead to more violent outbreaks. Behaviour also appears to be critical for control strategies as we found a bigger sensitivity to behavioural interventions than antibiotic treatment. Thus, behavioural interventions may play a larger role than previously thought, especially in the face of antibiotic resistance and low intervention efficacies.
Hydrogen-bonded chains in 3,5-bis(4-fluorophenyl)-1-phenyl-1H-pyrazole and complex hydrogen-bonded sheets in (5RS,6SR)-6-(4-fluorobenzoyl)-5-(4-fluorophenyl)-2-(4-hydroxyphenyl)-5,6-dihydro-4H-1,3,4-oxadiazineN,N-dimethylformamide monosolvate
Authors: Samshuddin Seranthimata , Jasinski Jerry P. , Golen James A. , Narayana Badiadka , Yathirajan Hemmige S. , Glidewell Christopher
Published: August 2014

Two different heterocycles, a pyrazole and an oxadiazine, are formed by the reactions of a common precursor, (2RS,3SR)-2,3-dibromo-1,3-bis(4-fluorophenyl)propan-1-one, with different simple hydrazines. In 3,5-bis(4-fluorophenyl)-1-phenyl-1H-pyrazole, C21H14F2N2, (I), formed using phenylhydrazine, there is some aromatic-type delocalization in the pyrazole ring, and the molecules are linked into simple chains by a single C—H...π(arene) hydrogen bond. The reaction with 4-hydroxybenzohydrazide gives (5RS,6SR)-6-(4-fluorobenzoyl)-5-(4-fluorophenyl)-2-(4-hydroxyphenyl)-5,6-dihydro-4H-1,3,4-oxadiazine, which was crystallized fromN,N-dimethylformamide to give the monosolvate, C22H16F2N2O3·C3H7NO, (II), in which the solvent molecule is disordered over two sets of atomic sites having occupancies of 0.557 (10) and 0.443 (10). The oxadiazine molecules in (II) are linked by a combination of N—H...N and C—H...O hydrogen bonds to form complex sheets, having the hydrogen bonds in the central layer and with the solvent molecules attached at the outer faces by O—H...O hydrogen bonds.
Distinct temperament and character profiles in first onset vitiligo but not in alopecia areata
Authors: Erfan Gamze , Albayrak Yakup , Yanik M. Emin , Oksuz Ozden , Tasolar Kaan , Topcu Birol , Unsal Cuneyt
Published: August 2014

Alopecia areata (AA) and vitiligo (V) are diseases that are correlated with psychiatric disorders before, during and after diagnosis. The Temperament and Character Inventory (TCI) is a well‐established approach for investigating personality traits in various psychosomatic diseases. The aim of this study is to compare and investigate the differences in the TCI between patients with first onset AA, patients with V and healthy controls (HC). Participants in the study included 42 patients with first onset AA, 50 adult patients with V and 60 HC who had no history or diagnoses of psychiatric or dermatological disorders. All participants were assessed with the TCI and the Dermatology Life Quality Index (DLQI). Among the temperament traits, the extravagance, disorderliness and total novelty‐seeking scores were lower, and the worry and pessimism scores were higher in patients with V compared with patients with AA and the HC. The mean score of the enlightened second nature and the total self‐directedness score of the character traits were higher in patients with V compared with patients with AA and the HC group. In the AA group, there was a negative correlation only between the reward dependence total score and the DLQI score. This study suggests that patients with first onset V have a distinct temperament, such as being unenthusiastic and unemotional, and character profiles, such as worry and pessimism, independent of their psychiatric comorbidities, and patients with AA do not have a different personality from the non‐affected population.
Serum levels of matrix metalloproteinase‐13 in patients with eosinophilic fasciitis
Authors: Asano Yoshihide , Ihn Hironobu , Jinnin Masatoshi , Tamaki Zenshiro , Tamaki Kunihiko , Sato Shinichi
Published: August 2014

Matrix metalloproteinase‐13 (MMP‐13), a member of the collagenase family, has been implicated in the pathogenesis of connective tissue diseases characterized by extracellular matrix remodeling. Since serum MMP‐13 levels reflect disease severity of systemic sclerosis and localized scleroderma, we evaluated the clinical significance of serum MMP‐13 levels in eosinophilic fasciitis (EF). All the EF patients had serum MMP‐13 levels lower than the mean – 2SD of healthy controls. Serum MMP‐13 levels were also significantly decreased in EF patients compared with diffuse cutaneous systemic sclerosis, limited cutaneous systemic sclerosis, and generalized morphea patients. Although serum MMP‐13 levels did not reflect any clinical and serological features of EF, these results indicate that MMP‐13 may be involved in the development of this disease.
Prevention of hair graying by factors that promote the growth and differentiation of melanocytes
Authors: Endou Mariko , Aoki Hitomi , Kobayashi Tatsushi , Kunisada Takahiro
Published: August 2014

Epidermal melanocyte precursors migrate into developing hair follicles to form the melanocyte stem cell system required to supply pigmented melanocytes necessary for hair pigmentation in repetitive hair cycles. Hair graying is caused by irreversible defects in the self‐renewal and/or development of follicular melanocyte stem cells in the hair follicles. To investigate the mechanism(s) of hair graying during the normal aging process, we established a hair graying model in mice by repeatedly plucking or shaving trunk hairs. We repeatedly plucked or shaved trunk hairs to induce and accelerate the hair graying and counted the gray hairs. By using this functional model of hair graying in mice, we assessed the effects of genes known to affect melanocyte development, such as Kitl, hepatocyte growth factor (HGF) and endotheline 3 (ET3). After increasing the total numbers of cumulative hair cycles by plucking or shaving, we observed a significant increase in the gray hair of C57BL/6 mice. Kitl expression in the skin was the most effective for preventing hair graying and a significant effect was also confirmed for HGF and ET3 expression. The repeated hair plucking or shaving led to hair graying without any genetic lesion. Kitl is a more effective factor for prevention of hair graying than HGF or ET3. Our simple model of hair graying may provide a basic tool for screening the molecules or reagents preventing the progression of hair graying.
Mating type gene for isolates of Trichophyton mentagrophytes from guinea pigs
Authors: Hiruma Junichiro , Kano Rui , Kimura Utako , Takamori Kenji , Suga Yasushi , Hiruma Masataro , Hasegawa Atsuhiko , Tsuboi Ryoji
Published: August 2014

Trichophyton mentagrophytes were isolated from 19 of 20 guinea pigs in a children's corner of a zoo. The nucleotide sequence identity of the internal transcribed spacer region among 19 guinea pig isolates was 99%, including the reference strain of animal type 3 of T. mentagrophytes. The genomic DNA of all isolates were investigated for the mating (MAT) gene by specific polymerase chain reaction. The alpha‐box gene was detected in all 19 isolates, while the high‐mobility‐group (HMG) gene was detected in only one of 19 isolates. Therefore, the guinea pig population harbored at least 2 MAT types of Arthroderma vanbreuseghemii. The T. mentagrophytes that was prevalent in this population may constitute a constant source of infection for persons coming into contact with guinea pigs.
Adherence: A Concept Analysis
Authors: Gardner Carrie Lee
Published: August 2014

Purpose

To utilize a Wilsonian method of concept analysis to define and describe the concept of adherence.

Data Sources

Published research articles, nursing literature, published books, and national and international advisory reports.

Data Synthesis

The concept of adherence was analyzed using the Wilson method. Results, applications, and practice implications in regards to the concept of adherence were then derived from the analysis.

Conclusions

Adherence is a complex, multifaceted concept that can greatly impact patient behaviors and nursing practice. Further clarification of adherence is needed to help delineate this concept from other related terms.

Implications

Healthcare providers should have an understanding of the concept of adherence in the context of patient care in order to guide patient self‐care behaviors.