bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spiral Coating of the Endothelial Caveolar Membranes as Revealed by Electron Tomography and Template Matching
Authors: Lebbink Misjaël N. , Jiménez Nuria , Vocking Karin , Hekking Liesbeth H. , Verkleij Arie J. , Post Jan A. 
Published: October 2009

Abstract Caveolae are invaginations of the plasma membrane involved in multiple cellular processes, including transcytosis. In this paper we present an extensive 3‐D electron tomographic study of the endothelial caveolar system in situ. Analysis of large cellular volumes of (high‐pressure frozen, freeze‐substituted and epon‐embedded) human umbilical vein endothelial cells (HUVECs) provided a notable view on the architecture of the caveolar system that comprises – as confirmed by 3‐D immunolabeling for caveolin of ‘intact’ cells –bona fide caveolae, free plasmalemmal vesicles, racemose invaginations and free multi‐caveolar bodies. Application of template matching to tomograms allowed the 3‐D localization of caveolar membrane coatings in a robust manner. In this way we observed that bona fide endothelial caveolae, cryofixed and embedded in their cellular context, show a spiral organization of the coating as shown in the past for chemically fixed and freeze‐etched caveolae from fibroblasts. Meticulous 3‐D analysis further revealed that the coatings are distributed in triads of spirals over the caveolar bulb and neck. Remarkably, this coating distribution is consistently present over the membranes of the other members of the caveolar system in HUVECs. The novel observations that we present clarify the ultrastructural complexity of the ‘intact’ caveolar system, setting a detailed morphological basis for its functional diversity.
Effects of feeding level of milk replacer on body growth, plasma metabolite and insulin concentrations, and visceral organ growth of suckling calves
Authors: KAMIYA Mitsuru , MATSUZAKI Masatoshi , ORITO Hideki , KAMIYA Yuko , NAKAMURA Yoshi‐nori , TSUNEISHI Eisaku 
Published: October 2009

ABSTRACTThe objective was to evaluate effects of feeding level of milk replacer on body growth, plasma metabolite and insulin concentrations, and allometric growth of visceral organs in suckling calves. Holstein bull calves (n = 8; 3–4 days of age) were fed either a low amount (average 0.63 kgDM/day, LM) or high amount (average 1.15 kgDM/day, HM) of high protein milk replacer until they were slaughtered at 6 weeks of age. Body weight (BW) at 4, 5, and 6 weeks of age, feed intake, average daily gain, and feed efficiency were higher in the HM than LM calves. The HM group had higher plasma glucose at 3 and 4 weeks of age and insulin levels after the age of 4 weeks compared with LM calves whereas no effect was detected on plasma nonesterified fatty acid or urea nitrogen concentrations. The HM calves had greater empty body weight (EBW), viscera‐free BW and most of the organs dissected than LM calves. Relative weights (% of EBW) of liver, spleen, kidneys, and internal fat were higher, whereas head and large intestine was lower in HM than LM calves. The results suggest that increased milk feeding levels would accelerate the growth of the body and specific organs.
Dark matter dominated dwarf disc galaxy Segue 1
Authors: Xiang-Gruess Meng , Lou Yu-Qing , Duschl Wolfgang J. 
Published: October 2009

Abstract
Several observations reveal that dwarf galaxy Segue 1 has a dark matter (DM) halo at least ∼200 times more massive than its visible baryon mass of only ∼103 M⊙. The baryon mass is dominated by stars with perhaps an interstellar gas mass of ≲13 M⊙. Regarding Segue 1 as a dwarf disc galaxy by its morphological appearance of long stretch, we invoke the dynamic model of Xiang-Gruess, Lou & Duschl (XLD) to estimate its physical parameters for possible equilibria with and without an isopedically magnetized gas disc. We estimate the range of DM mass and compare it with available observational inferences. Due to the relatively high stellar velocity dispersion compared to the stellar surface mass density, we find that a massive DM halo would be necessary to sustain disc equilibria. The required DM halo mass agrees grossly with observational inferences so far. For an isopedic magnetic field in a gas disc, the ratio f between the DM and baryon potentials depends strongly on the magnetic field strength. Therefore, a massive DM halo is needed to counteract either the strong stellar velocity dispersion and rotation of the stellar disc or the magnetic Lorentz force in the gas disc. By the radial force balances, the DM halo mass increases for faster disc rotation.
Simulation of dark lanes in post-flare supra-arcade
Authors: Costa A. , Elaskar S. , Fernández C. A. , Martínez G. 
Published: October 2009

Abstract
We integrate the magnetohydrodynamics (MHD) ideal equations to simulate dark void sunwardly moving structures in post-flare supra-arcades. We study the onset and evolution of the internal plasma instability to compare with observations and to gain insight into physical processes and characteristic parameters of these phenomena. The numerical approach uses a finite-volume Harten–Yee total variation diminishing (TVD) scheme to integrate the 1D 1/2 MHD equations specially designed to capture supersonic flow discontinuities. The integration is performed in both directions, the sunward radial one and the transverse to the magnetic field. For the first time, we numerically reproduce observational dark voids described in Verwichte et al. We show that the dark tracks are plasma vacuums generated by the bouncing and interfering of shocks and expansion waves, upstream an initial slow magnetoacoustic shock produced by a localized deposition of energy modelled with a pressure perturbation. The same pressure perturbation produces a transverse to the field or perpendicular magnetic shock giving rise to non-linear waves that compose the kink-like plasma void structures, with the same functional sunward decreasing phase speed and constancy with height of the period, as those determined by the observations.
Discovery of a magnetic field in the O9 sub-giant star HD 57682 by the MiMeS Collaboration
Authors: Grunhut J. H. , Wade G. A. , Marcolino W. L. F. , Petit V. , Henrichs H. F. , Cohen D. H. , Alecian E. , Bohlender D. , Bouret J. C. , Kochukhov O. , Neiner C. , St Louis N. , Townsend R. H. D. 
Published: October 2009

Abstract
We report the detection of a strong, organized magnetic field in the O9IV star HD 57682, using spectropolarimetric observations obtained with ESPaDOnS at the 3.6 m Canada–France–Hawaii Telescope within the context of the Magnetism in Massive Stars (MiMeS) Large Programme. From the fitting of our spectra using non local thermodynamic equilibrium model atmospheres, we determined that HD 57682 is a 17+19−9M⊙ star with a radius of 7.0+2.4−1.8R⊙ and a relatively low mass loss rate of 1.4+3.1−0.95× 10−9M⊙yr−1. The photospheric absorption lines are narrow, and we use the Fourier transform technique to infer v sini= 15 ± 3 kms−1. This v sini implies a maximum rotational period of 31.5d, a value qualitatively consistent with the observed variability of the optical absorption and emission lines, as well as the Stokes V profiles and longitudinal field. Using a Bayesian analysis of the velocity resolved Stokes V profiles to infer the magnetic field characteristics, we tentatively derive a dipole field strength of 1680+134−356G. The derived field strength and wind characteristics imply a wind that is strongly confined by the magnetic field.
DNA barcoding of Cuban freshwater fishes: evidence for cryptic species and taxonomic conflicts
Authors: LARA ARIAGNA , PONCE de LEÓN JOSÉ LUIS , RODRÍGUEZ RODET , CASANE DIDIER , CÔTÉ GUILLAUME , BERNATCHEZ LOUIS , GARCÍA‐MACHADO ERIK 
Published: October 2009

AbstractDespite ongoing efforts to protect species and ecosystems in Cuba, habitat degradation, overuse and introduction of alien species have posed serious challenges to native freshwater fish species. In spite of the accumulated knowledge on the systematics of this freshwater ichthyofauna, recent results suggested that we are far from having a complete picture of the Cuban freshwater fish diversity. It is estimated that 40% of freshwater Cuban fish are endemic; however, this number may be even higher. Partial sequences (652 bp) of the mitochondrial gene COI (cytochrome c oxidase subunit I) were used to barcode 126 individuals, representing 27 taxonomically recognized species in 17 genera and 10 families. Analysis was based on Kimura 2‐parameter genetic distances, and for four genera a character‐based analysis (population aggregation analysis) was also used. The mean conspecific, congeneric and confamiliar genetic distances were 0.6%, 9.1% and 20.2% respectively. Molecular species identification was in concordance with current taxonomical classification in 96.4% of cases, and based on the neighbour‐joining trees, in all but one instance, members of a given genera clustered within the same clade. Within the genus Gambusia, genetic divergence analysis suggests that there may be at least four cryptic species. In contrast, low genetic divergence and a lack of diagnostic sites suggest that Rivulus insulaepinorum may be conspecific with Rivulus cylindraceus. Distance and character‐based analysis were completely concordant, suggesting that they complement species identification. Overall, the results evidenced the usefulness of the DNA barcodes for cataloguing Cuban freshwater fish species and for identifying those groups that deserve further taxonomic attention.
Ocular blood flow assessment using continuous laser Doppler flowmetry
Authors: Riva Charles E. , Geiser Martial , Petrig Benno L. ,   for the Ocular Blood Flow Research Association
Published: October 2009

Acta Ophthalmol. 2010: 88: 622–629Abstract.This article describes the technique of continuous laser Doppler flowmetry (LDF) as applied to the measurement of the flux of red blood cells in the optic nerve head, iris and subfoveal choroid. Starting with the exposition of the physical principles underlying LDF, we first describe the various devices developed to perform LDF in these vascular beds. We then discuss the clinical protocols, blood flow parameters, calibration procedures, reproducibility and limitations of the LDF technique. Various problems still need to be solved in order to bring to light the full potential of LDF in the assessment of microcirculatory haemodynamics.
On the deformation chirality of real cubic fourfolds
Authors: Finashin S. , Kharlamov V. 
Published: October 2009

AbstractAccording to our previous results, the conjugacy class of the involution induced by the complex conjugation in the homology of a real non-singular cubic fourfold determines the fourfold up to projective equivalence and deformation. Here, we show how to eliminate the projective equivalence and obtain a pure deformation classification, that is, how to respond to the chirality problem: which cubics are not deformation equivalent to their image under a mirror reflection. We provide an arithmetical criterion of chirality, in terms of the eigen-sublattices of the complex conjugation involution in homology, and show how this criterion can be effectively applied taking as examples M-cubics (that is, those for which the real locus has the richest topology) and (M−1)-cubics (the next case with respect to complexity of the real locus). It happens that there is one chiral class of M-cubics and three chiral classes of (M−1)-cubics, in contrast to two achiral classes of M-cubics and three achiral classes of (M−1)-cubics.
Linear free divisors and Frobenius manifolds
Authors: Gregorio Ignacio de , Mond David , Sevenheck Christian 
Published: October 2009

AbstractWe study linear functions on fibrations whose central fibre is a linear free divisor. We analyse the Gauß–Manin system associated to these functions, and prove the existence of a primitive and homogenous form. As a consequence, we show that the base space of the semi-universal unfolding of such a function carries a Frobenius manifold structure.
Medication use by athletes during the Athens 2004 Paralympic Games
Authors: Tsitsimpikou C , Jamurtas A , Fitch K , Papalexis P , Tsarouhas K 
Published: October 2009

Objective:To examine the use of food supplements and pharmaceutical preparations by elite Paralympic athletes.Design:Survey study.Setting:Athens 2004 Paralympic Games.Participants:Data obtained from two sources: (i) athletes’ declaration of intake of drugs/supplements recorded on the Doping Control Official Record during sample collection for doping control; (ii) athletes’ application forms for granting of a therapeutic use exemption.Main outcome measures:Classification of declared food supplements according to the active ingredient and medications according to therapeutic actions and active compounds.Results:64.2% of the athletes tested for doping control declared use of medications or food supplements, and 81.3% of these athletes declared intake of fewer than four preparations. Non-invasive routes of administration dominated. Food supplements (42.1%) were popular, and drugs used to treat several pathological conditions noted. Non-steroidal anti-inflammatory agents and analgesics were commonly used (9.8% and 5.6%, respectively). The prevalence of inhaled β2-agonist use (4.8%) was higher than expected and exceeded that at the Athens Olympic Games.Conclusions:This review, the first to examine elite Paralympic athletes, shows a more rational approach to the use of medication and food supplements, but a similar consumption pattern to that of athletes at the Athens Olympic Games. Because of the dearth of such studies, consumption trends among Paralympic athletes remain unclear. The need to counsel athletes with disabilities on their nutritional needs is confirmed, and close monitoring by healthcare professionals is recommended.
Decreased incidence of knee posterior cruciate ligament injury in Australian Football League after ruck rule change
Authors: Orchard J W , Seward H 
Published: October 2009

Objective:To assess whether a rule change introduced in the Australian Football League (AFL) before the start of the 2005 season, to limit the run-up of ruckmen at the centre bounce, has been successful in reducing the incidence of knee posterior cruciate ligament (PCL) injuriesDesign:Cohort study with historical control.Setting:The AFL competition from 1992 to 2008 inclusive.Assessment of risk factors:The presence of a rule change (four seasons) compared with the previous 13 seasons (divided into two eras of seven and six seasons).Main outcome measure:Occurrence of knee PCL injury during a regular season or finals match, both from all causes and specifically from centre bounce ruck collision mechanisms.Results:From 1992 to 1998 there were 11.0 PCL injuries per 10 000 player-hours, with 0.8 ruck injuries per 10 000 centre bounces. From 1999 to 2004, the rates increased to 12.9 per 10 000 player-hours and 5.6 ruck injuries per 10 000 centre bounces (p<0.01). The rates reduced to 5.9 PCL injuries per 10 000 player-hours and 0.9 ruck injuries per 10 000 centre bounces in the period 2005–2008 following the rule change (p<0.01). There was a lower relative risk in 2005–2008 than in 1999–2004 of incurring a centre bounce ruck PCL injury (0.16 (95% CI 0.04 to 0.69)) or of sustaining any PCL injury (0.45 (95% CI 0.28 to 0.75)).Conclusion:A rule change in the AFL to limit the run-up of ruckmen at the centre bounce has successfully reduced the rate of PCL injuries with this mechanism, with the total incidence of PCL injuries also falling.
Optimal pacing strategy: from theoretical modelling to reality in 1500-m speed skating
Authors: Hettinga F J , De Koning J J , Schmidt L J I , Wind N A C , MacIntosh B R , Foster C 
Published: October 2009

PurposeAthletes are trained to choose the pace which is perceived to be correct during a specific effort, such as the 1500-m speed skating competition. The purpose of the present study was to “override” self-paced (SP) performance by instructing athletes to execute a theoretically optimal pacing profile.MethodsSeven national-level speed-skaters performed a SP 1500-m which was analysed by obtaining velocity (every 100 m) and body position (every 200 m) with video to calculate total mechanical power output. Together with gross efficiency and aerobic kinetics, obtained in separate trials, data were used to calculate aerobic and anaerobic power output profiles. An energy flow model was applied to SP, simulating a range of pacing strategies, and a theoretically optimal pacing profile was imposed in a second race (IM).ResultsFinal time for IM was ∼2 s slower than SP. Total power distribution per lap differed, with a higher power over the first 300 m for IM (637.0 (49.4) vs 612.5 (50.0) W). Anaerobic parameters did not differ. The faster first lap resulted in a higher aerodynamic drag coefficient and perhaps a less effective push-off.ConclusionExperienced athletes have a well-developed performance template, and changing pacing strategy towards a theoretically optimal fast start protocol had negative consequences on speed-skating technique and did not result in better performance.
Observation of the chemiluminescent NO + O → NO2 + hν reaction in the upper mesospheric dark polar regions by OSIRIS on Odin
Authors: Gattinger R. L. , Evans W. F.J. , McDade I.C. , Degenstein D. A. , Llewellyn E. J. 
Published: October 2009

The visible and near infrared continuum spectrum produced by the NO + O → NO2 + hv chemiluminescent reaction has been detected in the upper mesospheric dark polar regions by OSIRIS on the Odin spacecraft. Averaged observed NO2 emission spectral shapes are obtained by spectrally resolving the NO + O continuum from the blended strong upper mesospheric OH vibration–rotation airglow bands. The observed continuum spectral shape when compared with laboratory measurements is shifted to lower wavelengths by approximately 20 nm in the steeply sloped 400 to 500 nm region. The observed laboratory continuum spectral shape for upper mesospheric ambient pressure is presented for reference over the 400 to 800 nm region. An example of an NO2 continuum volume emission-rate altitude profile derived from a single OSIRIS limb scan is also included. Limb radiances up to 3 × 109 photons cm–2 nm–1 s–1 are observed at the peak of the NO2 continuum corresponding to total volume emission rates of approximately 2 × 104 photons cm–3 s–1. Data extracted from numerous single-volume emission-rate altitude profiles obtained over approximately a 24 h period are assembled into a Southern Hemisphere polar map of the 90 km NO2 continuum emission. The map illustrates the considerable spatial brightness variation typically observed in the dark Antarctic polar region throughout the OSIRIS mission dataset. After further analysis these measurements will assist in quantifying the role of thermospheric formed NOx in the catalytic removal of ozone in the upper stratosphere.
Exact exchange-correlation potentials in spin-density functional theory and their discontinuities at unit electron number
Authors: Perdew John P. , Sagvolden Espen 
Published: October 2009

The exact exchange-correlation potential of Kohn–Sham density functional theory is known to jump discontinuously by a spatial constant as the average electron number, N, crosses an integer in an open system of fluctuating electron number, with important physical consequences for charge transfers and band gaps. We have recently constructed an essentially exact exchange-correlation potential vxc for N electrons (0 ≤ N ≤ 2) in the presence of a –1/r external potential, i.e., for a ground ensemble of H+ ion, H atom, and H– ion densities. That construction illustrates the discontinuity at N = 1, where it equals IH – AH, the positive difference between the ionization energy and the electron affinity of the hydrogen atom. Here we construct the corresponding essentially exact spin-up and spin-down exchange-correlation potentials vxc,↑ and vxc,↓ of the Kohn–Sham spin-density functional theory, more commonly used for electronic structure calculations, for the ground ensemble with most-negative z-component of spin (or equivalently in the presence of a uniform magnetic field of infinitesimal strength). The potentials vxc, vxc,↑, and vxc,↓, which vanish as r → ∞ (except when N approaches an integer from above), are identical for 0 ≤ N ≤ 1 and for N = 2 but not for 1 < N < 2. We find that the majority or spin-down potential has a spatially constant discontinuity at N = 1 equal to IH – AH. The minority or spin-up potential has a discontinuity which is this constant in one order of limits, but is a spatially varying function in a different order of limits. This order-of-limits problem is a consequence of a special circumstance: the vanishing of the spin-up density at N = 1.
Kohn–Sham DFT and ligand-field theory — Is there a synergy?
Authors: Schäffer Claus E. , Bendix Jesper 
Published: October 2009

In forming electronic states of the partially filled shell of transition-metal atomic and molecular systems, real, symmetry-based, fixed, Kohn–Sham eigenorbitals can be used to bridge KS-states with strong-field, ligand-field states. Thereby, DFT computations, restrained by the use of these frozen orbitals of the so-called average-of-configuration type, allow a central-field modeling of the partially filled shell whose Hamiltonian matrix consists of mutually orthogonal diagonal and non-diagonal parts, of which only the former can be computed. Mutually orthogonal operators of ligand-field theory are particularly suited to parameterize the energy “data” obtained from the bridges between molecular Kohn–Sham DFT states and ligand-field states. With the d2 configuration as the simplest example encompassing both ligand-field and interelectronic repulsion, each one-electron parameter, though defined by energy differences of perturbed d orbitals, is associated with a 45 × 45, diagonal, theoretical, strong-field-type coefficient matrix of the ligand field repulsion model (LFR), which is mapped in a one-to-one fashion onto a likewise diagonal KS-DFT computational energy matrix. For sets of mutually orthogonal operators, the mapping determines the value of any such ligand-field parameter as a scalar product between the DFT matrix and the coefficient matrix of the associated ligand-field operator. Each and every two-electron parameter of LFR is in the same strong-field function basis associated with a 45 × 45 coefficient matrix that includes a non-diagonal part. This matrix, nevertheless, by the formation of a scalar product with the appropriate diagonal, computational DFT matrix, provides the value of the two-electron parameter. In spite of the lacking non-diagonal DFT information, its non-diagonal elements of the two-electron interelectronic repulsion matrices are indirectly accessible through the parameterization based upon the computed diagonal DFT matrices combined with the mapping of the DFT energy results onto the parametric LFR. In this way, LFR delivers back to DFT a quantification of the deviation of the systems’ eigenbasis from the DFT-computed states, which are defined by having unit occupation numbers. This work focuses firstly on using the LFR model for forming a full DFT energy matrix and dissecting it into mutually orthogonal one- and two-electron parts and secondly on the use of the two-electron parts to obtain a complete ligand-field image of a nephelauxetic, molecular atom, intrinsic of the chemical system.