bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spectral width of premonsoon and monsoon clouds over Indo‐Gangetic valley
Authors: Prabha Thara V. , Patade S. , Pandithurai G. , Khain A. , Axisa D. , Pradeep‐Kumar P. , Maheshkumar R. S. , Kulkarni J. R. , Goswami B. N. 
Published: September 2012

The combined effect of humidity and aerosol on cloud droplet spectral width (σ) in continental monsoon clouds is a topic of significant relevance for precipitation and radiation budgets over monsoon regions. The droplet spectral width in polluted, dry premonsoon conditions and moist monsoon conditions observed near the Himalayan Foothills region during Cloud Aerosol Interaction and Precipitation Enhancement EXperiment (CAIPEEX) is the focus of this study. Here σis small in premonsoon clouds developing from dry boundary layers. This is attributed to numerous aerosol particles and the absence/suppression of collision‐coalescence during premonsoon. For polluted and dry premonsoon clouds,σ is constant with height. In contrast to premonsoon clouds, σ in monsoon clouds increases with height irrespective of whether they are polluted or clean. The mean radius of polluted monsoon clouds is half that of clean monsoon clouds. In monsoon clouds, both mean radius and σ decreased with total cloud droplet number concentration (CDNC). The spectral widths of premonsoon clouds were independent of total droplet number concentrations, but both σ and mean radius decreased with small droplet (diameter < 20 μm) number concentrations in the diluted part of the cloud. Observational evidence is provided for the formation of large droplets in the adiabatic regions of monsoon clouds. The number concentration of small droplets is found to decrease in the diluted cloud volumes that may be characterized by various spectral widths or mean droplet radii.
Melting and refreezing beneath Roi Baudouin Ice Shelf (East Antarctica) inferred from radar, GPS, and ice core data
Authors: Pattyn F. , Matsuoka K. , Callens D. , Conway H. , Depoorter M. , Docquier D. , Hubbard B. , Samyn D. , Tison J. L. 
Published: September 2012

Ice‐penetrating radar profiles across the grounding line of a small ice‐rise promontory located within the Roi Baudouin Ice Shelf in the Dronning Maud Land sector of East Antarctica show downward dipping englacial radar‐detected reflectors. Model results indicate that this reflector pattern is best fit by including basal melting of at least 15 cm a−1. This rate of melting is low compared with rates observed on larger ice shelves in both West and East Antarctica. Ice cores extracted from a rift system close to the ice‐rise promontory show several meters of marine ice accreted beneath the shelf. These observations of low rates of basal melting, and limited distribution of accreted marine ice suggest that either Antarctic surface water may reach the ice shelf base or that circulation beneath the shelf is likely dominated by the production of high salinity shelf water rather than the incursion of circumpolar deep water, implying a weak sub‐shelf circulation system here. Many of the ice shelves located along the coast of Dronning Maud Land are, like Roi Baudouin Ice Shelf, characterized by frequent ice rises and promontories. Therefore, it is highly likely that these are also of shallow bathymetry and are subject to similarly weak side‐shelf basal melting and refreezing.
Downhole variation of lithium and oxygen isotopic compositions of oceanic crust at East Pacific Rise, ODP Site 1256
Authors: Gao Y. , Vils F. , Cooper K. M. , Banerjee N. , Harris M. , Hoefs J. , Teagle D. A. H. , Casey J. F. , Elliott T. , Laverne C. , Alt J. C. , Muehlenbachs K. 
Published: September 2012

Bulk rock lithium and oxygen isotope compositions from ODP Site 1256 were analyzed to investigate the seawater circulation in the upper oceanic crust formed at the East Pacific Rise (EPR). The upper extrusive basalts have δ18O values from +6.1‰ to +9.2‰, reflecting alteration of oceanic crust by seawater at low temperatures (<200–250°C). Bulk rocks from the sheeted dike complex and plutonic section have overall lower δ18O values (+3.0‰–+5.5‰). In the sheeted dike complex bulk rock δ18O values gradually decrease with depth, and then increase toward the fresh MORB δ18O value after reaching a minimum of +3.0‰ at ∼1350 m below seafloor (mbsf). The entire sampled crust is dominated by rocks with low lithium contents relative to fresh MORBs except for a few localized Li enrichment. The upper volcanic zone is characterized by a spread of δ7Li from low to high values relative to average unaltered MORB values (δ7Li = +3.4 ± 1.4‰). The presence of rocks with low δ7Li values in the upper crust most likely indicates zones of upwelling of relatively hot (∼200–250°C) hydrothermal fluids. In the sheeted dike complex, bulk rock δ7Li values show wide range of variation, but exhibit a general trend from enriched to depleted values at ∼1280 mbsf and then return to that for fresh MORB within the upper tens of meters of the plutonic section at the bottom of the after reaching a minimum at ∼1350 mbsf (δ7Li = −1.6‰). The downhole pattern of δ7Li principally reflects variations in water‐rock ratio (w/r) together with a downhole increase of temperature. Seawater flow in the upper volcanic zone is likely to be channeled with generally small but variable w/r ratios. The w/r ratios increase rapidly with depth in the lower volcanic section into the sheeted dike complex indicating water dominated pervasive hydrothermal flow due to intensive upwelling of hydrothermal fluids.
Variations in sediment transport at the central Argentine continental margin during the Cenozoic
Authors: Gruetzner Jens , Uenzelmann‐Neben Gabriele , Franke Dieter 
Published: September 2012

The construction of the sedimentary cover at most passive continental margins includes gravitational downslope transport and along‐slope contourite deposition, which are controlled by tectonics, climate and oceanography. At the eastern continental margin of Argentina the history of deposition and erosion is intimately linked to the evolution of the South Atlantic and its water masses. Here we present a detailed seismic investigation of the mixed depositional system located between 41°S and 45°S. The study provides a northward complement to prior investigations from the southern Argentine margin and together with these may be used as background information for future ocean drilling in the region. Prominent features in our seismic cross sections are submarine canyons, mass wasting deposits, contourite channels, and sediment drifts. Four major seismic units above regional reflector PLe (∼65 Ma) are separated by distinct unconformities of regional extent. Using a dense grid of reflection seismic profiles, we mapped the depocenter geometries of the seismic units and derived a chronology of the depositional processes during the Cenozoic. While the Paleocene/Eocene (∼65–34 Ma) is characterized by hemipelagic sedimentation under relatively sluggish bottom water conditions, strong Antarctic bottom water (AABW) circulation led to widespread erosion on the slope and growth of a detached sediment drift during the Oligocene and early Miocene (∼34–17 Ma). After deposition of an aggradational seismic unit interpreted to represent the Mid‐Miocene climatic optimum (∼17–14 Ma), gravitational downslope sediment transport increased during the middle to late Miocene (∼14–6 Ma) possibly related to tectonic uplift in South America. The Pliocene to Holocene unit (<∼6 Ma) is very heterogeneous and formed by interactions of downslope and along‐slope sediment transport processes as indicated by the evolution of canyons, slope plastered drifts and channels.
Comparing VHF coherent scatter from the radar aurora with incoherent scatter and all‐sky auroral imagery
Authors: Hysell D. , Miceli R. , Munk J. , Hampton D. , Heinselman C. , Nicolls M. , Powell S. , Lynch K. , Lessard M. 
Published: September 2012

VHF coherent scatter radar observations of an auroral substorm over Alaska are analyzed in the context of multibeam incoherent scatter plasma density and drifts data and green‐line all‐sky optical imagery. Coherent scatter arises from Farley Buneman waves which are excited in theEregion whenever the convection electric field is greater than about 20 mV/m. Aperture synthesis radar imaging and other aspects of the methodology facilitate the precise spatial registration of the coherent scatter with coincident optical and incoherent scatter radar measurements. Discrete auroral arcs were found to separate diffuse regions of coherent backscatter and, sometimes, to align with the boundaries of those regions. At other times, auroral arcs and torches lined up adjacent to discrete, structured regions or radar backscatter. Drastic variations in the Doppler shifts of the coherent scatter from one side of the auroral forms to the other suggest the presence of field‐aligned currents. An empirical formula based on previous studies but adapted to account approximately for the effects of wave turning was used to estimate the convection electric field from the moments of the coherent scatter Doppler spectra. Line‐of‐sightF region plasma drift measurements from the Poker Flat Incoherent Scatter Radar (PFISR) were found to be in reasonable agreement with these convection field estimates. Reasons why the empirical formulas may be expected to hold are discussed.
Deciphering the role of southern gateways and carbon dioxide on the onset of the Antarctic Circumpolar Current
Authors: Lefebvre Vincent , Donnadieu Yannick , Sepulchre Pierre , Swingedouw Didier , Zhang Zhong‐Shi 
Published: September 2012

Growth of Antarctic ice sheet during the Cenozoic 34 million years ago appears as a potential tipping point in the long term cooling trend that began 50 Ma ago. For decades, the onset of the Antarctic Circumpolar Current (ACC) following the opening of the Drake Passage and of the Tasman Seaway has been suggested as the main driver of the continental‐scale Antarctic glaciation. However, recent modeling works emphasized that the Eocene/Oligocene atmospheric carbon dioxide (CO2) lowering could be the primary forcing of the Antarctic glaciation, questioning the ACC theory. Here, we investigate the response of the ACC to changes in CO2concentrations occurring from the late Eocene to the late Oligocene. We used a fully coupled atmosphere‐ocean model (FOAM) with a mid‐Oligocene geography. We find that the opening of southern oceanic gateways does not trigger the onset of the ACC for CO2typical of the late Eocene (>840 ppm). A cooler background climatic state such as the one prevalent at the end of the Oligocene is required to simulate a well‐developed ACC. In this cold configuration, the intensified sea‐ice development around Antarctica and the resulting brine formation lead to a strong latitudinal density gradient in the Southern Ocean favoring the compensation of the Ekman transport, and consequently the ACC. Our results imply that the ACC has acted as a feedback rather than as a driver of the global cooling.
The ACE2 gene: its potential as a functional candidate for cardiovascular disease
Authors: Burrell Louise M. , Harrap Stephen B. , Velkoska Elena , Patel Sheila K. 
Published: September 2012

The RAS (renin–angiotensin system) plays an important role in the pathophysiology of CVD (cardiovascular disease), and RAS blockade is an important therapeutic strategy in the management of CVD. A new counterbalancing arm of the RAS is now known to exist in which ACE (angiotensin-converting enzyme) 2 degrades Ang (angiotensin) II, the main effector of the classic RAS, and generates Ang-(1–7). Altered ACE2 expression is associated with cardiac and vascular disease in experimental models of CVD, and ACE2 is increased in failing human hearts and atherosclerotic vessels. In man, circulating ACE2 activity increases with coronary heart disease, as well as heart failure, and a large proportion of the variation in plasma ACE2 levels has been attributed to hereditary factors. The ACE2 gene maps to chromosome Xp22 and this paper reviews the evidence associating ACE2 gene variation with CVD and considers clues to potential functional ACE2 variants that may alter gene expression or transcriptional activity. Studies to date have investigated ACE2 gene associations in hypertension, left ventricular hypertrophy and coronary artery disease, but the results have been inconsistent. The discrepancies may reflect the sample size of the studies, the gender or ethnicity of subjects, the cardiovascular phenotype or the ACE2 SNP investigated. The frequent observation of apparent sex-dependence might be of special importance, if confirmed. As yet, there are no studies to concurrently assess ACE2 gene polymorphisms and circulating ACE2 activity. Large-scale carefully conducted clinical studies are urgently needed to clarify more precisely the potential role of ACE2 in the CVD continuum.
Impact of Food Intake, Ultrasound Transducer, Breathing Maneuvers and Body Position on Acoustic Radiation Force Impulse (ARFI) Elastometry of the Liver
Authors: Goertz R. , Egger C. , Neurath M. , Strobel D. 
Published: September 2012

Abstract
Purpose: Since acoustic radiation force impulse (ARFI) elastometry is an increasingly popular method for the assessment of hepatic fibrosis and cirrhosis, we investigated factors possibly influencing hepatic elastometric measurements.
Materials and Methods: 30 healthy volunteers (17 females, 13 males) were recruited. The shear wave velocity of the right liver lobe was determined in a fasting upright and supine position and after different breathing maneuvers with the convex array (4C1) and in a supine position with the linear (9L4) ultrasound transducer. In 18 volunteers, subsequent measurements were obtained in a fasting state and 30, 60, 90 and 120 min after ingestion of a standardized breakfast. A group of 8 patients (average age: 76 years) with right heart insufficiency was also evaluated.
Results: In the fasting state, the ARFI shear wave velocities measured in an upright position were significantly higher than those in supine position (p< 0.0001). The supine ARFI values were significantly higher with the linear transducer than with the convex transducer (p = 0.0034). The results in deep inspiration, deep expiration and during Valsalva maneuver showed no differences. The food intake-related ARFI elastometric measurements were significantly elevated at time points 30 min (p = 0.019) and 60 min (p = 0.036) postprandial. In right heart insufficiency, the ARFI values were elevated.
Conclusion: Hepatic ARFI elastometry is a well evaluated method. A standardized examination should include measuring in a supine position with the convex transducer (4C1) without specific breathing maneuvers. Since ARFI elastometry values increase after food intake, measurements should be performed in the fasting state, or not earlier than 2 hours postprandially. Heart dysfunction may impair ARFI accuracy.
Interdisciplinary Consensus Recommendations for the use of Vacuum-Assisted Breast Biopsy under Sonographic Guidance: First update 2012
Authors: Hahn M. , Krainick-Strobel U. , Toellner T. , Gissler J. , Kluge S. , Krapfl E. , Peisker U. , Duda V. , Degenhardt F. , Sinn H. , Wallwiener D. , Gruber I. ,   In cooperation with the Minimally Invasive Breast Intervention Study Group (AG MiMi) of the German Society of Senology (DGS),   and the Study Group for Breast Ultrasonography of the German Society for Ultrasound in Medicine (DEGUM)
Published: September 2012

Abstract
Purpose: The vacuum biopsy of the breast under sonographic guidance (VB) was introduced in Germany in the year 2000 and the first consensus recommendations were published by Krainick-Strobel et al. in 2005. Since then, many clinical studies on this technique have been published. The purpose of this publication is to update the consensus recommendations from 2005 regarding the latest literature.
Materials and Methods: The consensus statements were the result of two preliminary meetings after the review of the latest literature by members of the Minimally Invasive Breast Intervention Study Group from the German Society of Senology. The final consensus text was review by all members of the working group. The statements listed under results obtained complete acceptance (consensus 100 %).
Results: The consensus recommendations describe the indications, investigator qualifications, technical requirements, documentation, quality assurance and follow-up intervals regarding the latest literature.
Conclusion: The VB is a safe method for extracting breast tissue for histological workup. The technique allows the resection of breast tissue up to 8 cm3. Besides the diagnostic indications, the method qualifies for a therapeutic resection of symptomatic benign lesions (e. g. fibroadenomas). The technique should be used in specialized breast centers working in a multidisciplinary setup. This paper is an expert’s recommendation for the use of VB under sonographic guidance. It is not formulated as a nationwide guideline.
An EFSUMB Introduction into Dynamic Contrast-Enhanced Ultrasound (DCE-US) for Quantification of Tumour Perfusion
Authors: Dietrich C. , Averkiou M. , Correas J.-M. , Lassau N. , Leen E. , Piscaglia F. 
Published: September 2012

AbstractDynamic Contrast Enhanced Ultrasound (DCE-US) is an imaging technique that utilizes microbubble contrast agents in diagnostic ultrasound. The EFSUMB guidelines published in 2004, updated in 2008 and 2011 focused on the use of DCE-US, including essential technical requirements, training, investigational procedures and steps, guidance on image interpretation, established and recommended clinical indications and safety considerations. However the quantification of images acquired with ultrasound contrast agents (UCAs) is not discussed in the guidelines. The purpose of this EFSUMB document is to provide some recommendations and descriptions of the quantification of ultrasound images, technical requirements for analysis of time-intensity curves (TICs), methodology for data analysis, and interpretation of the results.
BRINGING THE DEMOS BACK IN
Authors: Antonsich Marco 
Published: September 2012

ABSTRACT
The creation of a EUropean demos is often debated by referring to forms of ethnic or civic identities. The present article aims to expose the theoretical shortcomings of this dichotomous approach, which confines the complexity of EUrope within a simplifying methodological nationalism. By relying on empirical data collected in four different EUropean regions, the article points to the relevance of a functional or utilitarian rationale which EUropean interviewees use to justify the existence of EUrope. Although this rationale does not obliterate cultural and civic narrations of EUrope, I would argue that it invites to reconsider the traditional role played by identities in the construction of political institutions. Accordingly, I believe that scholars should take more seriously the metaphor ‘EUrope as a laboratory’ – a convenient, but often empty metaphor.
Epitaxial silicene: can it be strongly strained?
Authors: Le Lay G , De Padova P , Resta A , Bruhn T , Vogt P 
Published: September 2012

Abstract
The possibility to synthesize honeycomb silicene has recently been demonstrated upon providing compelling evidence through the combination of complementary experimental results and density functional theory calculations (Vogt et al 2012 Phys. Rev.
Lett.
108 155501). In this case silicene is grown on Ag(1 1 1) substrates and shows a nearest neighbour distance of two Si atoms of ∼0.23 nm in agreement with theoretical results for free-standing silicene. In another publication from another group of authors a different silicene arrangement has been claimed previously, where the silicene sheet is strongly compressed with a Si–Si distance amounting to only 0.19 nm (Lalmi et al 2010 Appl. Phys. Lett.
97 223109). This has led to the fundamental question whether silicene could support such a large compressive strain. We will show that the apparent contradictions in the literature can be explained based on a thorough analysis, which reveals that the pure Ag(1 1 1) surface can mimic a honeycomb structure, which could easily be misinterpreted as a strained silicene layer. Our discussion will show that there is no evidence for the existence of such strong compressively strained silicene layers.
Elimination of high transient currents and electrode damage during electroformation of TiO2-based resistive switching devices
Authors: Lu Yi Meng , Noman Mohammad , Chen Wenhao , Salvador Paul A , Bain James A , Skowronski Marek 
Published: September 2012

Abstract
Transient currents associated with electroforming TiO2-based resistive switching devices were measured using three distinct circuits designed to limit them, and they were correlated with physical changes in the top electrode using scanning electron microscopy. A transient current more than 10 times greater than expected was observed when only using the source meter to limit the current via the compliance set point. The large excursion arose from equipment delays and resulted in significant physical changes to the top electrode. An external resistor was used to decrease the excess transient current value to nearly zero, as long as parasitic capacitive discharges were also suppressed. Simultaneously, the physical changes to the top electrode were completely suppressed, indicating physical damage was related to Joule heating from the excess forming currents. The switching characteristics of all devices were similar, implying damage during electroformation of functional switches can be avoided by device/circuit design.
A simple route to carbon micro- and nanorod hybrid structures by physical vapour deposition
Authors: Chu Jin , Peng Xiaoyan , Aldalbahi Ali , Panhuis Marc in het , Velazquez Rafael , Feng Peter X 
Published: September 2012

Abstract
Tilted well-aligned carbon micro- and nano-hybrid rods were synthesized on Si at different substrate temperatures and incident angles of carbon source beam using the hot filament physical vapour deposition technique. The morphologic surfaces, chemical compositions and bond structures of the oblique carbon rod-like structures were investigated by scanning electron microscopy, field emission scanning electron microscopy, transmission electron diffraction and Raman scattering spectroscopy. The field emission behaviour of the fabricated samples was also measured.
Relativistic terahertz pulse generation by non-linear interaction of a high-power fs laser with underdense plasmas
Authors: Kim J J , Jang D G , Hur M S , Jang H , Suk H 
Published: September 2012

Abstract
Generation of a terahertz radiation by the interaction of a highly intense laser (I
L ⩾ 1018 W cm−2) and an underdense plasma with relativistic effects has been investigated. The results of two-dimensional particle-in-cell simulations for the relativistic frequency shift of the emitted THz pulse are presented. It was found that the emitted THz frequency is shifted down with the scaling of γ
−α
, where γ is the Lorentz factor of the driving laser pulse and α is roughly 0.2 and slightly depends on the laser spot size. Furthermore, the monotonic linear dependence of the THz field strength on the incident laser power was observed. Comparison of the non-relativistic and relativistic laser power regime is shown as well.
LiF/Fe/C nanofibres as a high-capacity cathode material for Li-ion batteries
Authors: Zhang Shu , Lu Yao , Xu Guanjie , Li Ying , Zhang Xiangwu 
Published: September 2012

Abstract
LiF/Fe/C composite nanofibres with different morphologies were prepared by electrospinning and heat treatment of LiF/ferrocene/polyacrylonitrile (PAN) precursors. X-ray diffraction and scanning electron microscopy were employed to study the structural variations of these composite nanofibres. It was found that Fe nanoparticles and carbon nanofibres were obtained from the thermal decomposition of ferrocene and PAN precursors, respectively. The electrochemical performance was evaluated using the prepared composite nanofibres as the cathode material in lithium half-cells. With uniformly embedded active particles in the carbon nanofibre matrix, the resultant cathode materials presented highly reversible discharge capacities of over 472 mA h g−1.