bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparative Analysis of Media and Supplements on Initiation and Expansion of Adipose-Derived Stem Cells
Authors: Riis Simone , Nielsen Frederik Mølgaard , Pennisi Cristian Pablo , Zachar Vladimir , Fink Trine 
Published: February 2016

Abstract

Adipose-derived stem cells (ASCs) are being tested in clinical trials related to cell-based regenerative therapies. Although most of the current expansion protocols for ASCs use fetal calf serum (FCS), xenogeneic-free medium supplements are greatly desired. This study aims to compare the effect of FCS, human platelet lysate (hPL), and a fully defined medium on the initiation and maintenance of ASC cultures. ASCs obtained from five donors were cultured in five different media: StemPro, Dulbecco's modified Eagle's medium (DMEM) supplemented with 10% hPL, or α-minimum essential medium (A-MEM) supplemented with 5% hPL, 10% hPL, or 10% FCS. The effect of media on proliferation, colony-forming units (CFUs), attachment, and morphology was assessed along with cell size, granularity, and immunophenotype. StemPro greatly compromised the initiation of ASC cultures, which could not survive more than a few passages. Cells cultured in A-MEM proliferated at a faster rate than in DMEM, and hPL significantly enhanced cell size, granularity, and proliferation compared with FCS. All media except StemPro supported CFUs equally well. Analysis of surface markers revealed higher levels of CD73 and CD105 in FCS-cultured ASCs, whereas increased levels of CD146 were found in hPL-cultured cells. Multiparametric flow cytometric analysis performed after seven passages revealed the existence of four distinct ASC subpopulations, all positive for CD73, CD90, and CD105, which mainly differed by their expression of CD146 and CD271. Analysis of the different subpopulations might represent an important biological measure when assessing different medium formulations for a particular clinical application.

Significance
In most clinical trials using adipose-derived stem cells (ASCs), the cells have been expanded in culture media supplemented with fetal calf serum. However, there is much interest in replacing fetal calf serum with human platelet lysate or using completely serum- and xenogeneic-free media. This study found that culture in fetal calf serum versus human platelet lysate had a significant effect on the degree of expression of stem cell–associated surface markers. These results underscore the need to carefully investigate the effect of culture media on ASC behavior before committing to one medium type for clinical use.
Los efectos profesionales de la crisis de la televisión pública española: el creador audiovisual low cost y las nuevas tecnologías
Authors: Heredero Díaz Olga , Reyes Sánchez Francisco Jaime 
Published: February 2016

El sector televisivo español, en el que los efectos de la crisis económica y la falta de alternativas de financiación hacen estragos, se configura a nivel nacional como un pseudo-oligopolio en torno a una entidad pública, TVE, y dos grandes grupos empresariales audiovisuales, Mediaset, con Telecinco y Cuatro como principales cadenas, y Atresmedia, con Antena 3 y La Sexta. Las consecuencias del cambio de modelo que ha transformado TVE en una entidad financiada con recursos públicos, sin publicidad comercial y con una política de programas a coste cero, junto con la renovación tecnológica, la democratización de la difusión de contenidos de elaboración propia y el abaratamiento de costes, marca el día a día de los nuevos creadores low cost, que deben adaptarse a los efectos profesionales de la crisis de la radiotelevisión pública para no quedarse fuera de un mercado cada vez más competitivo e incierto. La descripción de dichos efectos, tanto en el sistema de trabajo del creador audiovisual del siglo XXI, como en su perfil profesional, junto a la identificación de los factores causantes de su reconversión, son los objetivos de esta investigación. Así, mediante una revisión bibliográfica y un análisis cualitativo con entrevistas en profundidad, no estructuradas, a los profesionales implicados, el artículo verifica sus dos hipótesis de partida: por un lado, que la transformación del sistema de trabajo del creador audiovisual en TVE ha incrementado su precariedad y, por otro, que su perfil profesional se ha ampliado a áreas funcionales no artísticas (financiación, producción, edición, etc.).
Fiabilité d’un dispositif d’évaluation de l’habileté à déterminer le résultat d’une chaîne d’opérations chez des élèves québécois du secondaire
Authors: Hébert Marie-Hélène , Valois Pierre , Scallon Gérard , Frenette Éric 
Published: February 2016

La présente étude examine la possibilité d’évaluer avec un bon niveau de fiabilité l’habileté des élèves à déterminer le résultat d’une chaîne d’opérations en respectant la priorité des opérations. Selon le devis de recherche, deux facteurs liés à l’énoncé du problème ont été manipulés : son degré de réalisme et la complétude de ses données. À la suite d’une préexpérimentation, un ensemble de 12 problèmes ont été présentés à 82 élèves québécois de première secondaire. Afin d’évaluer les qualités édumétriques du dispositif d’évaluation constitué, les données ont été analysées au moyen de la théorie de la généralisabilité. Des coefficients de généralisabilité inférieurs à la limite jugée satisfaisante révèlent que le dispositif d’évaluation n’est pas assez fiable pour assurer la différenciation des élèves en regard de leur habileté à déterminer le résultat d’une chaîne d’opérations. Les résultats démontrent la difficulté d’évaluer avec un bon niveau de fiabilité l’habileté des élèves lorsque sont manipulés deux facteurs liés à l’énoncé du problème : son degré de réalisme et la complétude de ses données.
Beyond optical enhancement due to embedded metal nanoparticles in thin-film solar cells
Authors: Mopurisetty Sundara Murthy , Bajaj Mohit , Ganguly Swaroop 
Published: February 2016

Abstract
Metal nanoparticles (MNPs) inside the active layer of thin-film solar cells are considered promising for light trapping, but they have also engendered concerns over their adverse impact on transport properties. Contrary to expectations, coupled optical and electrical simulations indicate that a purely electrical effect due to MNPs might result in an enhancement of the cell performance in addition to the gain from optical (plasmonic) effects. This electrical enhancement strongly depends on the MNP/semiconductor barrier height. On the other hand, the anticipated degradation due to trap states and surface recombination at the MNP/semiconductor interface may in fact be negligible.
Observation of localized states in bulk GaAs using ultrafast photocurrent beat spectroscopy
Authors: Tahara Hirokazu , Kanemitsu Yoshihiko 
Published: February 2016

Abstract
We report photocurrent (PC)-generation processes in bulk GaAs at low temperatures revealed by PC beat spectroscopy and photoluminescence (PL) measurements. Because the time-domain PC spectroscopy is highly sensitive to PC-generation processes, several PC generation sites, including localized states, were identified. The difference between the PC beat and PL spectra shows that a non-luminescent bound-exciton state predominantly generates PC at intermediate temperatures, which is difficult to observe using steady-state PC and PL measurements. Thus, PC beat spectroscopy provides detailed understanding of the PC-generation processes in semiconductors.
Dissolved organic carbon in the deep Southern Ocean: Local versus distant controls
Authors: Bercovici Sarah K. , Hansell Dennis A. 
Published: February 2016

AbstractThe global ocean contains a massive reservoir (662 ± 32 Pg C) of dissolved organic carbon (DOC), and its dynamics, particularly in the deepest zones, are only slowly being understood. DOC in the deep ocean is ubiquitously low in concentration (~35 to 48 µmol kg−1) and aged (4000 to 6000 years), persisting for multiple meridional overturning circulations. Deep waters relatively enriched in DOC form in the North Atlantic, migrate to the Southern Ocean to mix with waters from Antarctic shelves and the deep Pacific and Indian Oceans, in turn forming the voluminous waters of the Circumpolar Deep Water. Here we seek evidence for local (autochthonous) versus distant (allochthonous) processes in determining the distribution of DOC in the deep Southern Ocean. Prior analyses on DOC in the deep Southern Ocean have conflicted, describing both conservative and nonconservative traits: the deep DOC field has been reported as uniform in distribution, yet local inputs have been suggested as quantitatively important. We use multiple approaches (multiple linear regression, mass transport, and mass balance calculations) with data from Climate Variability and Predictability Repeat Hydrography sections to evaluate the system. We find that DOC concentrations in the deep Southern Ocean largely reflect the conservative mixing of the several deep waters entering the system from the north. Mass balance suggests that the relatively depleted DOC radiocarbon content in the deep Southern Ocean is a conserved property as well. These analyses advance our understanding of the controls on the DOC reservoir of the Southern Ocean.
A mass budget for mercury and methylmercury in the Arctic Ocean
Authors: Soerensen Anne L. , Jacob Daniel J. , Schartup Amina T. , Fisher Jenny A. , Lehnherr Igor , St. Louis Vincent L. , Heimbürger Lars‐Eric , Sonke Jeroen E. , Krabbenhoft David P. , Sunderland Elsie M. 
Published: February 2016

AbstractElevated biological concentrations of methylmercury (MeHg), a bioaccumulative neurotoxin, are observed throughout the Arctic Ocean, but major sources and degradation pathways in seawater are not well understood. We develop a mass budget for mercury species in the Arctic Ocean based on available data since 2004 and discuss implications and uncertainties. Our calculations show that high total mercury (Hg) in Arctic seawater relative to other basins reflect large freshwater inputs and sea ice cover that inhibits losses through evasion. We find that most net MeHg production (20 Mg a−1) occurs in the subsurface ocean (20–200 m). There it is converted to dimethylmercury (Me2Hg: 17 Mg a−1), which diffuses to the polar mixed layer and evades to the atmosphere (14 Mg a−1). Me2Hg has a short atmospheric lifetime and rapidly degrades back to MeHg. We postulate that most evaded Me2Hg is redeposited as MeHg and that atmospheric deposition is the largest net MeHg source (8 Mg a−1) to the biologically productive surface ocean. MeHg concentrations in Arctic Ocean seawater are elevated compared to lower latitudes. Riverine MeHg inputs account for approximately 15% of inputs to the surface ocean (2.5 Mg a−1) but greater importance in the future is likely given increasing freshwater discharges and permafrost melt. This may offset potential declines driven by increasing evasion from ice‐free surface waters. Geochemical model simulations illustrate that for the most biologically relevant regions of the ocean, regulatory actions that decrease Hg inputs have the capacity to rapidly affect aquatic Hg concentrations.
Effects of crystallization and bubble nucleation on the seismic properties of magmas
Authors: Tripoli Barbara Andrea , Cordonnier Benoit , Zappone Alba , Ulmer Peter 
Published: February 2016

AbstractSeismic tomography of potentially hazardous volcanoes is a prime tool to assess the location and dimensions of magmatic reservoirs. Seismic velocities are strongly affected by processes occurring within the conduit or in the magma chamber, such as crystallization and bubble exsolution. However, the limited number of constrained measurements does not allow yet to link seismic tomography and the textural state of a particular volcanic system. In this study, we investigated a chemically simplified melt in the system CaO‐Na2O‐Al2O3‐SiO2‐H2O‐CO2, which undergoes plagioclase crystallization and bubble exsolution. A Paterson‐type internally heated gas pressure apparatus was employed to measure ultrasonic velocities at a constant pressure of 250 MPa and at temperature from 850 to 700°C. Magmatic processes such as crystallization, bubble nucleation, and coalescence have been recognized throughout the measurements of seismic velocities in the laboratory. Compression and shear wave velocities increase nonlinearly during crystallization. At a crystal fraction exceeding 0.45, the formation of a crystal network favors the propagation of seismic waves through magmatic liquids. However, bubble nucleation induced by crystallization leads to an increase of magma compressibility resulting in a lowering of the wave propagation velocities. These two processes occur simultaneously and have a competing influence on the seismic properties of magmas. In addition, as already observed by previous authors, when the bubble fraction is less than 0.10, the decrease in seismic velocities is more pronounced than for higher bubble fractions. The effect of bubble coalescence on elastic properties is thus lower than the effect of bubble nucleation.
Comprehensive Pb‐Sr‐Nd‐Hf isotopic, trace element, and mineralogical characterization of mafic to ultramafic rock reference materials
Authors: Fourny Anaïs , Weis Dominique , Scoates James S. 
Published: February 2016

AbstractControlling the accuracy and precision of geochemical analyses requires the use of characterized reference materials with matrices similar to those of the unknown samples being analyzed. We report a comprehensive Pb‐Sr‐Nd‐Hf isotopic and trace element concentration data set, combined with quantitative phase analysis by XRD Rietveld refinement, for a wide range of mafic to ultramafic rock reference materials analyzed at the Pacific Centre for Isotopic and Geochemical Research, University of British Columbia. The samples include a pyroxenite (NIM‐P), five basalts (BHVO‐2, BIR‐1a, JB‐3, BE‐N, GSR‐3), a diabase (W‐2), a dolerite (DNC‐1), a norite (NIM‐N), and an anorthosite (AN‐G); results from a leucogabbro (Stillwater) are also reported. Individual isotopic ratios determined by MC‐ICP‐MS and TIMS, and multielement analyses by HR‐ICP‐MS are reported with 4–12 complete analytical duplicates for each sample. The basaltic reference materials have coherent Sr and Nd isotopic ratios with external precision below 50 ppm (2SD) and below 100 ppm for Hf isotopes (except BIR‐1a). For Pb isotopic reproducibility, several of the basalts (JB‐3, BHVO‐2) require acid leaching prior to dissolution. The plutonic reference materials also have coherent Sr and Nd isotopic ratios (<50 ppm), however, obtaining good reproducibility for Pb and Hf isotopic ratios is more challenging for NIM‐P, NIM‐N, and AN‐G due to a variety of factors, including postcrystallization Pb mobility and the presence of accessory zircon. Collectively, these results form a comprehensive new database that can be used by the geochemical community for evaluating the radiogenic isotope and trace element compositions of volcanic and plutonic mafic‐ultramafic rocks.
Linear and nonlinear effects of dominant drivers on the trends in global and regional land carbon uptake: 1959 to 2013
Authors: Zhang Xuanze , Rayner Peter J. , Wang Ying‐Ping , Silver Jeremy D. , Lu Xingjie , Pak Bernard , Zheng Xiaogu 
Published: February 2016

AbstractChanges in atmospheric CO2 levels, surface temperature, or precipitation have been identified to have significantly contributed to the estimated increase in the terrestrial carbon uptake rate over the last few decades; however, those analyses did not consider the interactions. Using the Australian community land surface model (Community Atmosphere Biosphere Land Exchange), we performed factorial experiments to quantify the importance of external drivers (climate drivers and atmospheric CO2) and their interactions on annual terrestrial carbon uptake (FL), excluding land use change and fires, from 1959 to 2013. Our model simulations show a trend of 0.025 ± 0.015 Pg C yr−2 (or ~1.5% yr−1) in global FL for 1959–2013, which is largely attributed to the positive influences of the increased atmospheric CO2 (0.050 ± 0.001 Pg C yr−2) and negative influences of changes in climate (−0.026 ± 0.014 Pg C yr−2). Globally, the contribution of the nonlinear effects of dominant drivers to the simulated trend in FL is small (<10%) but can be significant regionally (>35%), particularly in the boreal forests and semiarid regions. The interactions between temperature and CO2 or temperature and precipitation can dominate the simulated trend in parts of Europe, southeastern North America, southern China, and some semiarid regions. This modeling result suggests that the effects of nonlinear interactions of drivers on the trend of land carbon uptake should be considered in future studies.
Structured subauroral polarization streams and related auroral undulations occurring on the storm day of 21 January 2005
Authors: Horvath Ildiko , Lovell Brian C. 
Published: February 2016

AbstractWe investigate structured subauroral polarization streams (SAPS) and their impacts on the midlatitude trough and auroral regions during the 21–22 January 2005 geomagnetic storm. This was a storm with two sudden commencements occurring under varying interplanetary magnetic field (IMF) conditions and three main phases, two of them unfolding during northward IMF. Its onset at ~1700 UT allowed us to investigate SAPS wave structures (WS) and their impacts during the local evening hours under both southward and northward IMF conditions in the American sector. Results suggest that during southward IMF, SAPS‐WS might be related with standing (toroidal) Alfven waves and structured most intensively the stagnation trough. During northward IMF, the trough was created by SAPS electric (E) field effects only and became less structured by SAPS‐WS that were of Alfvenic origin. Auroral wave structures and undulations occurred in the structured and unstructured oval regions, respectively, and triggered the subauroral region's response to produce SAPS‐WS. Spectrogram images (only one shown) confirmed ring current injections implying magnetotail reconnections during the four SAPS‐WS events investigated. Periodic tail connections are also evidenced by the periodic increases seen in both the solar wind‐magnetosphere coupling function (ε) and the energy input efficiency. Finally, we conclude for the time period investigated that (1) the nature of SAPS‐WS was informative of IMF orientation, (2) plasma stagnation enhanced SAPS E field and SAPS‐WS development, and (3) more efficient energy input into the magnetosphere contributed to the better development of auroral undulations and SAPS‐WS.
Key elements of a low voltage, ultracompact plasma spectrometer
Authors: Scime E. E. , Barrie A. , Dugas M. , Elliott D. , Ellison S. , Keesee A. M. , Pollock C. J. , Rager A. , Tersteeg J. 
Published: February 2016

AbstractTaking advantage of technological developments in wafer‐scale processing over the past two decades, such as deep etching, 3‐D chip stacking, and double‐sided lithography, we have designed and fabricated the key elements of an ultracompact (1.5 cm)3 plasma spectrometer that requires only low‐voltage power supplies, has no microchannel plates, and has a high aperture area to instrument volume ratio. The initial design of the instrument targets the measurement of charged particles in the 3–20 keV range with a highly directional field of view and a 100% duty cycle; i.e., the entire energy range is continuously measured. In addition to reducing mass, size, and voltage requirements, the new design will affect the manufacturing process of plasma spectrometers, enabling large quantities of identical instruments to be manufactured at low individual unit cost. Such a plasma spectrometer is ideal for heliophysics plasma investigations, particularly for small satellite and multispacecraft missions. Two key elements of the instrument have been fabricated: the collimator and the energy analyzer. An initial collimator transparency of 20% with 3° × 3° angular resolution was achieved. The targeted 40% collimator transparency appears readily achievable. The targeted energy analyzer scaling factor of 1875 was achieved; i.e., 20 keV electrons were selected for only a 10.7 V bias voltage in the energy analyzer.
A study of radar backscattering from water surface in response to rainfall
Authors: Liu Xinan , Zheng Quanan , Liu Ren , Wang Dan , Duncan James H. , Huang Shih‐Jen 
Published: February 2016

AbstractIn this paper, radar backscattering from a water surface in response to rainfall was studied. The paper consists of two parts. First, the spatial characteristics of raindrops in rain fields were analyzed based on published data and the response of a water surface to rainfall was experimentally studied in the laboratory. Rain‐generated surface features including stalks, crowns, ring waves, and secondary drops were measured. It was found that stalks and crowns are dominant in terms of their height and energy. Second, the radar signatures of a rainfall event simultaneously observed by C band ENVISAT (European satellite), ASAR (Advanced Synthetic Aperture Radar), and ground‐based weather radar in the Northwest Pacific were investigated. The relationship between the radar return intensity extracted from the C band ASAR image and the reflectivity factor (rain rate) obtained from ground‐based weather radar was analyzed. For light/moderate rain (with low reflectivity factors), the radar backscattering intensity increases as the reflectivity factor increases. For heavy rain (with high reflectivity factors), the radar backscattering intensity decreases as the reflectivity factor increases. The maximum radar backscattering intensity occurs at a reflectivity factor of 45 dBZ (with rain rate of 24 mm/h). It was found that the spaceborne radar backscattering intensity strongly correlates with the average distance between the stalks on the water surface in the rain field in a nonlinear manner. The physics of the radar signatures of the rain event are explored.
Quantifying the fate of agricultural nitrogen in an unconfined aquifer: Stream‐based observations at three measurement scales
Authors: Gilmore Troy E. , Genereux David P. , Solomon D. Kip , Solder John E. , Kimball Briant A. , Mitasova Helena , Birgand François 
Published: February 2016

AbstractWe compared three stream‐based sampling methods to study the fate of nitrate in groundwater in a coastal plain watershed: point measurements beneath the streambed, seepage blankets (novel seepage‐meter design), and reach mass‐balance. The methods gave similar mean groundwater seepage rates into the stream (0.3–0.6 m/d) during two 3–4 day field campaigns despite an order of magnitude difference in stream discharge between the campaigns. At low flow, estimates of flow‐weighted mean nitrate concentrations in groundwater discharge ([
]FWM) and nitrate flux from groundwater to the stream decreased with increasing degree of channel influence and measurement scale, i.e., [
]FWM was 654, 561, and 451 µM for point, blanket, and reach mass‐balance sampling, respectively. At high flow the trend was reversed, likely because reach mass‐balance captured inputs from shallow transient high‐nitrate flow paths while point and blanket measurements did not. Point sampling may be better suited to estimating aquifer discharge of nitrate, while reach mass‐balance reflects full nitrate inputs into the channel (which at high flow may be more than aquifer discharge due to transient flow paths, and at low flow may be less than aquifer discharge due to channel‐based nitrate removal). Modeling dissolved N2 from streambed samples suggested (1) about half of groundwater nitrate was denitrified prior to discharge from the aquifer, and (2) both extent of denitrification and initial nitrate concentration in groundwater (700–1300 µM) were related to land use, suggesting these forms of streambed sampling for groundwater can reveal watershed spatial relations relevant to nitrate contamination and fate in the aquifer.