bluuebunny/crossref_metadata_2025_split huggingface dataset:
Repair of chronic rupture of the insertion of the gastrocnemius tendon in the dog using a polyethylene terephthalate implant
Authors: Thomson D. G. , Rayward R. M. , Jiménez-Peláez M. , Whitelock R. G. , Morton M. A. 
Published: March 2015

SummaryObjectives: Chronic degeneration of the gastrocnemius tendon results in scar tissue formation at the insertion of the tendon, and detachment from the calcaneus. In severe cases, excision of this tissue makes repositioning of the tendon to the calcaneus extremely difficult. A polyethylene terephtha-late implant, used to aide repair by bridging gaps and allowing tissue ingrowth, was evaluated.Methods: In this retrospective study, clinical records were evaluated to assess long-term outcomes and complications. The surgical technique is also described. The implant was sutured proximally into the gastrocnemius at the myotendinous junction, and secured into the calcaneus using an interference screw.Results: The implant was used in 10 patients; of which seven returned to full function. Major complications, due to infection, were identified in two of the 10 patients. Minor complications occurred in five of the 10 patients. These were associated with external coaptation in three of the patients in the immediate postoperative period. One minor infection was reported. These all resolved without further complication. Long-term outcome was available in eight patients, with six of these eight dogs returning to normal exercise.Clinical significance: This implant may be suitable for use in canine patients with severe gastrocnemius tendon degeneration. Ongoing evaluation is warranted.
L’importance grandissante des évaluations au sein des parlements : Les gouvernements tenus de rendre des comptes ?
Authors: Pattyn Valérie , Speer Sandra , De Peuter Bart 
Published: March 2015

Rares sont ceux qui, à ce jour, se sont intéressés au rôle des évaluations au sein des parlements, ce qui est surprenant étant donné que les députés sont parties prenantes par excellence, que les évaluations pourraient intéresser. Mais est-ce effectivement le cas ? C’est sur la base d’une analyse systématique des questions écrites et des interpellations en Allemagne et en Flandre que nous allons nous pencher sur l’intérêt des députés pour les évaluations. Nous analyserons les aspects suivants, d’un point de vue comparatif : le contenu des questions sur les évaluations, le profil politique des députés qui posent les questions, la part de questions sur les évaluations et la répartition des questions entre les partis politiques, les domaines stratégiques et au fil du temps. Remarques à l’intention des praticiens Le rôle et l’utilisation des évaluations dans le processus démocratique sont des choses à améliorer. D’une part, les députés au Parlement souhaitent parfois être mieux informés sur les méthodes d’évaluation, ainsi que sur les possibilités d’utiliser les résultats d’évaluation à des fins d’imputabilité et d’apprentissage. D’autre part, ce sont parfois les évaluateurs qui s’efforcent de renforcer la demande d’évaluations dans le processus d’élaboration des politiques, et pas seulement l’administration publique.
The effects of secular calcium and magnesium concentration changes on the thermodynamics of seawater acid/base chemistry: Implications for Eocene and Cretaceous ocean carbon chemistry and buffering
Authors: Hain Mathis P. , Sigman Daniel M. , Higgins John A. , Haug Gerald H. 
Published: March 2015

AbstractReconstructed changes in seawater calcium and magnesium concentration ([Ca2+], [Mg2+]) predictably affect the ocean's acid/base and carbon chemistry. Yet inaccurate formulations of chemical equilibrium “constants” are currently in use to account for these changes. Here we develop an efficient implementation of the MIAMI Ionic Interaction Model to predict all chemical equilibrium constants required for carbon chemistry calculations under variable [Ca2+] and [Mg2+]. We investigate the impact of [Ca2+] and [Mg2+] on the relationships among the ocean's pH, CO2, dissolved inorganic carbon (DIC), saturation state of CaCO3 (Ω), and buffer capacity. Increasing [Ca2+] and/or [Mg2+] enhances “ion pairing,” which increases seawater buffering by increasing the concentration ratio of total to “free” (uncomplexed) carbonate ion. An increase in [Ca2+], however, also causes a decline in carbonate ion to maintain a given Ω, thereby overwhelming the ion pairing effect and decreasing seawater buffering. Given the reconstructions of Eocene [Ca2+] and [Mg2+] ([Ca2+]~20 mM; [Mg2+]~30 mM), Eocene seawater would have required essentially the same DIC as today to simultaneously explain a similar‐to‐modern Ω and the estimated Eocene atmospheric CO2 of ~1000 ppm. During the Cretaceous, at ~4 times modern [Ca2+], ocean buffering would have been at a minimum. Overall, during times of high seawater [Ca2+], CaCO3 saturation, pH, and atmospheric CO2 were more susceptible to perturbations of the global carbon cycle. For example, given both Eocene and Cretaceous seawater [Ca2+] and [Mg2+], a doubling of atmospheric CO2 would require less carbon addition to the ocean/atmosphere system than under modern seawater composition. Moreover, increasing seawater buffering since the Cretaceous may have been a driver of evolution by raising energetic demands of biologically controlled calcification and CO2 concentration mechanisms that aid photosynthesis.
Isotopic evidence for nitrification in the Antarctic winter mixed layer
Authors: Smart Sandi M. , Fawcett Sarah E. , Thomalla Sandy J. , Weigand Mira A. , Reason Chris J. C. , Sigman Daniel M. 
Published: March 2015

AbstractWe report wintertime nitrogen and oxygen isotope ratios (δ15N and δ18O) of seawater nitrate in the Southern Ocean south of Africa. Depth profile and underway surface samples collected in July 2012 extend from the subtropics to just beyond the Antarctic winter sea ice edge. We focus here on the Antarctic region (south of 50.3°S), where application of the Rayleigh model to depth profile δ15N data yields estimates for the isotope effect (the degree of isotope discrimination) of nitrate assimilation (1.6–3.3‰) that are significantly lower than commonly observed in the summertime Antarctic (5–8‰). The δ18O data from the same depth profiles and lateral δ15N variations within the mixed layer, however, imply O and N isotope effects that are more similar to those suggested by summertime data. These findings point to active nitrification (i.e., regeneration of organic matter to nitrate) within the Antarctic winter mixed layer. Nitrite removal from samples reveals a low δ15N for nitrite in the winter mixed layer (−40‰ to −20‰), consistent with nitrification, but does not remove the observation of an anomalously low δ15N for nitrate. The winter data, and the nitrification they reveal, explain the previous observation of an anomalously low δ15N for nitrate in the temperature minimum layer (remnant winter mixed layer) of summertime depth profiles. At the same time, the wintertime data require a low δ15N for the combined organic N and ammonium in the autumn mixed layer that is available for wintertime nitrification, pointing to intense N recycling as a pervasive condition of the Antarctic in late summer.
Helium isotope, C/3He, and Ba‐Nb‐Ti signatures in the northern Lau Basin: Distinguishing arc, back‐arc, and hotspot affinities
Authors: Lupton John , Rubin Ken H. , Arculus Richard , Lilley Marvin , Butterfield David , Resing Joseph , Baker Edward , Embley Robert 
Published: March 2015

AbstractThe northern Lau Basin hosts a complicated pattern of volcanism, including Tofua Arc volcanoes, several back‐arc spreading centers, and individual “rear‐arc” volcanoes not associated with these structures. Elevated 3He/4He ratios in lavas of the NW Lau Spreading Center suggest the influence of a mantle plume, possibly from Samoa. We show that lavas from mid‐ocean ridges, volcanic arcs, and hotspots occupy distinct, nonoverlapping fields in a 3He/4He versus C/3He plot. Applied to the northern Lau Basin, this approach shows that most of Lau back‐arc spreading systems have mid‐ocean ridge 3He/4He‐C/3He characteristics, except the NW Lau spreading center, which has 3He/4He‐C/3He similar to “high 3He” hotspots such as Loihi, Kilauea, and Yellowstone, but with slightly lower C/3He. Niua seamount, on the northern extension of the Tofua Arc, falls squarely in the arc field. All the NE Lau rear‐arc volcanoes, including the recently erupting West Mata, also have arc‐like 3He/4He‐C/3He characteristics. Ba‐Nb‐Ti contents of the lavas, which are more traditional trace element indicators of mantle source enrichment, depletion, and subduction input, likewise indicate arc and hot spot influences in the lavas of the northern Lau Basin, but in a more ambiguous fashion because of a complex prior history. This verifies that 3He/4He‐C/3He systematics are useful for differentiating between mid‐ocean ridge, arc, and hotspot affinities in submarine volcanic systems, that all three of these affinities are expressed in the northern Lau Basin, and provides additional support for the Samoan plume influence in the region.
How weak is the subduction zone interface?
Authors: Duarte João C. , Schellart Wouter P. , Cruden Alexander R. 
Published: March 2015

AbstractSeveral lines of evidence suggest that subduction zones are weak and that the unique availability of water on Earth is a critical factor in the weakening process. We have evaluated the strength of subduction zone interfaces using two approaches: (i) from empirical relationships between shear stress at the interface and subduction velocity, deduced from laboratory experiments; and (ii) from a parametric study of natural subduction zones that provides new insights on subduction zone interface strength. Our results suggest that subduction is only mechanically feasible when shear stresses along the plate interface are relatively low (less than ~35 MPa). To account for this requirement, we propose that there is a feedback mechanism between subduction velocity, water released from the subducting plate, and weakening of the fore‐arc mantle that may explain how relatively low shear stresses are maintained at subduction interfaces globally.
Nonlinear effects associated with kinetic Alfvén wave
Authors: Gaur Nidhi , Sharma R. P. 
Published: March 2015

AbstractThe nonlinear phenomena are of striking importance in understanding the particle acceleration, heating, and turbulence in the interplanetary space. Kinetic Alfvén wave (KAW) is one of the strong candidates responsible for accelerating the solar wind and powering the solar wind turbulence. Therefore, the nonlinear properties of KAW are attracting a good attention. In the present work, we have investigated the nonlinear effects associated with KAW in the solar wind plasma at around 1 A.U. The ponderomotive force of (relatively high frequency, high power) pump KAW may be used to excite the low‐frequency KAW (LKAW). For this purpose, we have derived the dynamical equations to analyze the nonlinear dynamics of relatively high frequency pump KAW in the presence of LKAW perturbation. The numerical solution has been carried out for the coupled system of equations by using the pseudospectral method for space integration and finite difference method along with the predictor corrector scheme for the evolution in time. The coupled system of nonlinear dynamical equations has been analyzed to study the nonlinear effects associated with pump KAW and the resulting turbulent spectra at 1 A.U.
Flow bursts, breakup arc, and substorm current wedge
Authors: Haerendel Gerhard 
Published: March 2015

AbstractEnergy liberated by the reconnection process in the near‐Earth tail is transported via flow bursts toward the dipolar magnetosphere during substorms. The breakup arc is a manifestation of the arrival of the bursts under flow braking and energy deposition. Its structure and behavior is analyzed on the basis of five striking spatial, temporal, and energetic properties, qualitatively and in part also quantitatively. A key element is the formation of stop layers. They are thin layers, of the width of an ion gyro radius, in which the magnetic field makes a transition from tail to near‐dipolar magnetosphere configurations and in which the kinetic energy of fast flows is converted into electromagnetic energy of kinetic Alfvén waves. The flows arise from the relaxation of the strong magnetic shear stresses in the leading part of the flow bursts. The bright narrow arcs of less than 10 km width inside the broad poleward expanding breakup arc, Alfvénic in nature and visually characterized by erratic short‐lived rays, are seen as traces of the stop layers. The gaps between two narrow and highly structured arcs are filled with more diffuse emissions. They are attributed to the relaxation of the less strained magnetic field of the flow bursts. Eastward flows along the arcs are linked to the shrinking gaps between two successive arcs and the entry of auroral streamers into the dipolar magnetosphere in the midnight sector. Flow braking in the stop layers forms multiple pairs of narrow balanced currents and cannot be behind the formation of the substorm current wedge. Instead, its origin is attributed to the force exerted by the dipolarized magnetic field of the flow bursts on the high‐beta plasma, after the high magnetic shears have relaxed and the fast flows and stop layer process have subsided, in other words, to the “dying flow bursts.”
Baroclinic instability and the mesoscale eddy field around the Lofoten Basin
Authors: Isachsen Pål Erik 
Published: March 2015

AbstractThe vigorous mesoscale eddy field around the Lofoten Basin west of northern Norway is thought to be related to eddy shedding from the Norwegian Atlantic Current flowing along the Norwegian coast. Here we study baroclinic instability in the current with a particular focus on the influence of topography. The flow over the steepest part of the continental slope is found to be the most unstable. The growth characteristics cannot be understood from Eady theory alone but require the consideration of interior potential vorticity gradients. A study of the fully developed macroturbulent field shows that eddy kinetic energy is advected away from the generation regions and that nonlinear effects likely draw the eddy statistics away from the linear growth regime.
An observational study of salt fluxes in Delaware Bay
Authors: Aristizábal María F. , Chant Robert J. 
Published: March 2015

AbstractAn observational study was conducted in Delaware Bay during the summer of 2011 aiming to quantify the different mechanisms driving the salt flux in this system. Seven moorings, equipped with bottom‐mounted ADCPs and CT sensors at difference depths, were deployed across a section of the estuary. The total area‐averaged and tidal‐averaged salt flux was decomposed in three different contributions: the advective salt flux that represents the flux caused by river input and meteorological‐induced flows, the steady shear dispersion that is the salt flux driven by the estuarine exchange flow, and the tidal oscillatory salt flux that is induced by the tidal currents. The advective salt flux dominated over the steady shear dispersion and tidal oscillatory salt flux, because it was driven mainly by changes in sea surface height associated with wind‐driven setup and setdown. The steady shear dispersion was always positive and presented a spring/neap variability that was consistent with a two‐layer exchange flow. On the other hand, the tidal oscillatory salt flux fluctuated between positive and negative values, but increased around a strong neap tide and decreased on the following spring tide. This variability is contrary to previous parameterizations, whereby the tidal salt flux is proportional to the amplitude of the tidal currents. The observational estimate was compared to a parameterization that relates tidal salt flux as proportional to tidal current amplitude and stratification. The observational estimate agreed with this new parameterization when the river discharge was relatively constant.
Thirteen thousand years of southeastern Mediterranean climate variability inferred from an integrative planktic foraminiferal‐based approach
Authors: Mojtahid Meryem , Manceau Rose , Schiebel Ralf , Hennekam Rick , de Lange Gert J. 
Published: March 2015

AbstractOver the past 13 ka, the hydrology for the southeastern Mediterranean was mainly regulated by Nile River runoff, which in turn was controlled by climate forcing. Being affected by orbital forcing, and the position of the Intertropical Convergence Zone (ITCZ), planktic foraminiferal data (assemblages, stable isotopes, and size properties) indicate three major periods. (1) From 13.0 to 11.5 ka, the upper water column was well‐mixed, cold, and productive. (2) From 11.5 to 6.4 ka, hydrology and foraminifers were affected by intensified monsoonal circulation. The enhanced size of Globigerinoides ruber is interpreted as a response to environmental stress caused by low‐saline waters. (3) After 6.4 ka, the southward retreat of the ITCZ caused a decrease in freshwater discharge and hence a return to ecological equilibrium. A drop in foraminifer diversity from 2.9 to 1.1 ka was related to more arid conditions, and limited supply of nutrients from the Nile River. We suggest a link to a negative North Atlantic Oscillation (NAO) marking the Roman Humid Period in the western Mediterranean, and in anti‐phase with the southeastern Mediterranean aridity. Because Nile River runoff exerted major control on surface hydrology, a connection to Indian and Pacific climate systems partially controlling precipitation over the Nile catchment area is hypothesized. From 1.1 to 0.54 ka, high foraminifer diversity indicates humid conditions synchronous to the Medieval Climate Anomaly under a positive NAO state. Over the past 0.54 ka encompassing the Little Ice Age, another arid period is indicated by a drop in foraminifer diversity.
Glacial‐interglacial changes in central tropical Pacific surface seawater property gradients
Authors: Lynch‐Stieglitz Jean , Polissar Pratigya J. , Jacobel Allison W. , Hovan Steven A. , Pockalny Robert A. , Lyle Mitchell , Murray Richard W. , Ravelo A. Christina , Bova Samantha C. , Dunlea Ann G. , Ford Heather L. , Hertzberg Jennifer E. , Wertman Christina A. , Maloney Ashley E. , Shackford Julia K. , Wejnert Katherine , Xie Ruifang C. 
Published: March 2015

AbstractMuch uncertainty exists about the state of the oceanic and atmospheric circulation in the tropical Pacific over the last glacial cycle. Studies have been hampered by the fact that sediment cores suitable for study were concentrated in the western and eastern parts of the tropical Pacific, with little information from the central tropical Pacific. Here we present information from a suite of sediment cores collected from the Line Islands Ridge in the central tropical Pacific, which show sedimentation rates and stratigraphies suitable for paleoceanographic investigations. Based on the radiocarbon and oxygen isotope measurements on the planktonic foraminifera Globigerinoides ruber, we construct preliminary age models for selected cores and show that the gradient in the oxygen isotope ratio of G. ruber between the equator and 8°N is enhanced during glacial stages relative to interglacial stages. This stronger gradient could reflect enhanced equatorial cooling (perhaps reflecting a stronger Walker circulation) or an enhanced salinity gradient (perhaps reflecting increased rainfall in the central tropical Pacific).
Front spreading with nonlinear sorption for oscillating flow
Authors: Cirkel D. G. , van der Zee S. E. A. T. M. , Meeussen J. C. L. 
Published: March 2015

AbstractIn this paper, we consider dispersive and chromatographic mixing at an interface, under alternating flow conditions. In case of a nonreactive or linearly sorbing solute, mixing is in complete analogy with classical dispersion theory. For nonlinear exchange, however, oscillating convective flow leads to an alternation of sharpening (Traveling Wave TW) and spreading (Rarefaction Wave RW). As the limiting TW form is not necessarily accomplished at the end of the TW half cycle, the oscillating fronts show gradual continuous spreading that converges to a zero‐convection nonlinear pure diffusion spreading, which is mathematically of quite different nature. This behavior is maintained in case the total (background) concentration differs at both sides of the initial exchange front.
Transport of fluorobenzoate tracers in a vegetated hydrologic control volume: 1. Experimental results
Authors: Queloz Pierre , Bertuzzo Enrico , Carraro Luca , Botter Gianluca , Miglietta Franco , Rao P. S. C. , Rinaldo Andrea 
Published: March 2015

AbstractThis paper reports about the experimental evidence collected on the transport of five fluorobenzoate tracers injected under controlled conditions in a vegetated hydrologic volume, a large lysimeter (fitted with load cells, sampling ports, and an underground chamber) where two willows prompting large evapotranspiration fluxes had been grown. The relevance of the study lies in the direct and indirect measures of the ways in which hydrologic fluxes, in this case, evapotranspiration from the upper surface and discharge from the bottom drainage, sample water and solutes in storage at different times under variable hydrologic forcings. Methods involve the accurate control of hydrologic inputs and outputs and a large number of suitable chemical analyses of water samples in discharge waters. Mass extraction from biomass has also been performed ex post. The results of the 2 year long experiment established that our initial premises on the tracers’ behavior, known to be sorption‐free under saturated conditions which we verified in column leaching tests, were unsuitable as large differences in mass recovery appeared. Issues on reactivity thus arose and were addressed in the paper, in this case attributed to microbial degradation and solute plant uptake. Our results suggest previously unknown features of fluorobenzoate compounds as hydrologic tracers, potentially interesting for catchment studies owing to their suitability for distinguishable multiple injections, and an outlook on direct experimental closures of mass balance in hydrologic transport volumes involving fluxes that are likely to sample differently stored water and solutes.
Transport of fluorobenzoate tracers in a vegetated hydrologic control volume: 2. Theoretical inferences and modeling
Authors: Queloz Pierre , Carraro Luca , Benettin Paolo , Botter Gianluca , Rinaldo Andrea , Bertuzzo Enrico 
Published: March 2015

AbstractA theoretical analysis of transport in a controlled hydrologic volume, inclusive of two willow trees and forced by erratic water inputs, is carried out contrasting the experimental data described in a companion paper. The data refer to the hydrologic transport in a large lysimeter of different fluorobenzoic acids seen as tracers. Export of solute is modeled through a recently developed framework which accounts for nonstationary travel time distributions where we parameterize how output fluxes (namely, discharge and evapotranspiration) sample the available water ages in storage. The relevance of this work lies in the study of hydrologic drivers of the nonstationary character of residence and travel time distributions, whose definition and computation shape this theoretical transport study. Our results show that a large fraction of the different behaviors exhibited by the tracers may be charged to the variability of the hydrologic forcings experienced after the injection. Moreover, the results highlight the crucial, and often overlooked, role of evapotranspiration and plant uptake in determining the transport of water and solutes. This application also suggests that the ways evapotranspiration selects water with different ages in storage can be inferred through model calibration contrasting only tracer concentrations in the discharge. A view on upscaled transport volumes like hillslopes or catchments is maintained throughout the paper.