bluuebunny/crossref_metadata_2025_split huggingface dataset:
Phototrophic pigment diversity and picophytoplankton in permafrost thaw lakes
Authors: Przytulska A. , Comte J. , Crevecoeur S. , Lovejoy C. , Laurion I. , Vincent W. F. 
Published: January 2016

Abstract. Permafrost thaw lakes (thermokarst lakes) are widely distributed across the northern landscape, and are known to be biogeochemically active sites that emit large amounts of carbon to the atmosphere as CH4 and CO2. However, the abundance and composition of the photosynthetic communities that fix CO2 have been little explored in this ecosystem type. In order to identify the major groups of phototrophic organisms and their controlling variables, we sampled 12 permafrost thaw lakes along a permafrost degradation gradient in northern Québec, Canada. Additional samples were taken from five rock-basin reference lakes in the region to determine if the thaw lakes differed in limnological properties and phototrophs. Phytoplankton community structure was determined by high-performance liquid chromatography analysis of their photoprotective and photosynthetic pigments, and autotrophic picoplankton concentrations were assessed by flow cytometry. One of the black-colored lakes located in a landscape of rapidly degrading palsas (permafrost mounds) was selected for high-throughput 18S rRNA sequencing to complement conclusions based on the pigment and cytometry analyses. The results showed that the limnological properties of the thaw lakes differed significantly from the reference lakes, and were more highly stratified. However, both waterbody types contained similarly diverse phytoplankton groups, with dominance of the pigment assemblages by fucoxanthin-containing taxa, as well as chlorophytes, cryptophytes and cyanobacteria. Chlorophyll a concentrations (Chl a) were correlated with total phosphorus (TP), and both were significantly higher in the thaw lakes (overall means of 3.3 µg Chl a L−1 and 34 µg TP L−1) relative to the reference lakes (2.0 µg Chl a L−1 and 8.2 µg TP L−1). Stepwise multiple regression of Chl a against the other algal pigments showed that it was largely a function of alloxanthin, fucoxanthin and Chl b (R2 =  0.85). The bottom waters of two of the thaw lakes also contained high concentrations of bacteriochlorophyll d, showing the presence of green photosynthetic sulphur bacteria. The molecular analyses indicated a relatively minor contribution of diatoms, while chrysophytes, dinoflagellates and chlorophytes were well represented; the heterotrophic eukaryote fraction was dominated by numerous ciliate taxa, and also included Heliozoa, Rhizaria, chytrids and flagellates. Autotrophic picoplankton occurred in biovolume concentrations up to 3.1  ×  105 µm3 picocyanobacteria  mL−1 and 1.9  × 106 µm3 picoeukaryotes mL−1, with large variations among lakes. Both groups of picophytoplankton were positively correlated with total phytoplankton abundance, as measured by Chl a; picocyanobacteria were inversely correlated with dissolved organic carbon, while picoeukaryotes were inversely correlated with conductivity. Despite their net heterotrophic character, subarctic thaw lakes are rich habitats for diverse phototrophic communities.
Insights into the transfer of silicon isotopes into the sediment record
Authors: Panizzo V. N. , Swann G. E. A. , Mackay A. W. , Vologina E. , Sturm M. , Pashley V. , Horstwood M. S. A. 
Published: January 2016

Abstract. The first δ30Sidiatom data from lacustrine sediment traps are presented from Lake Baikal, Siberia. Data are compared with March surface water (upper 180 m) δ30SiDSi compositions for which a mean value of +2.28‰ ±  0.09 (95 % confidence) is derived. This value acts as the pre-diatom bloom baseline silicic acid isotopic composition of waters (δ30SiDSi initial). Open traps were deployed along the depth of the Lake Baikal south basin water column between 2012 and 2013. Diatom assemblages display a dominance ( > 85 %) of the spring/summer bloom species Synedra acus var radians, so that δ30Sidiatom compositions reflect predominantly spring/summer bloom utilisation. Diatoms were isolated from open traps and, in addition, from 3-monthly (sequencing) traps (May, July and August 2012) for δ30Sidiatom analyses. Mean δ30Sidiatom values for open traps are +1.23‰ ±  0.06 (at 95 % confidence and MSWD of 2.9, n = 10). Total dry mass sediment fluxes are highest in June 2012, which we attribute to the initial export of the dominant spring diatom bloom. We therefore argue that May δ30Sidiatom signatures (+0.67‰ ±  0.06, 2σ) when compared with mean upper water δ30SiDSi initial (e.g. pre-bloom) signatures can be used to provide a snapshot estimation of diatom uptake fractionation factors (ϵuptake) in Lake Baikal. A ϵuptake estimation of −1.61 ‰ is therefore derived, although we emphasise that synchronous monthly δ30SiDSi and δ30Sidiatom data would be needed to provide more robust estimations and therefore more rigorously test this, particularly when taking into consideration any progressive enrichment of the DSi pool as blooms persist. The near-constant δ30Sidiatom composition in open traps demonstrates the full preservation of the signal through the water column and thereby justifies the use and application of the technique in biogeochemical and palaeoenvironmental research. Data are finally compared with lake sediment core samples, collected from the south basin. Values of +1.30‰ ±  0.08 (2σ) and +1.43‰ ±  0.13 (2σ) were derived for cores BAIK13-1C (0.6–0.8 cm core depth) and at BAIK13-4F (0.2–0.4 cm core depth) respectively. Trap data highlight the absence of a fractionation factor associated with diatom dissolution (ϵdissolution) (particularly as Synedra acus var radians, the dominant taxa in the traps, is very susceptible to dissolution) down the water column and in the lake surface sediments, thus validating the application of δ30Sidiatom analyses in Lake Baikal and other freshwater systems, in palaeoreconstructions.
Spatio-temporal variability of snow water equivalent in the extra-tropical Andes Cordillera from distributed energy balance modeling and remotely sensed snow cover
Authors: Cornwell E. , Molotch N. P. , McPhee J. 
Published: January 2016

Abstract. Seasonal snow cover is the primary water source for human use and ecosystems along the extratropical Andes Cordillera. Despite its importance, relatively little research has been devoted to understanding the properties, distribution and variability of this natural resource. This research provides high-resolution (500 m), daily distributed estimates of end-of-winter and spring snow water equivalent over a 152 000 km2 domain that includes the mountainous reaches of central Chile and Argentina. Remotely sensed fractional snow-covered area and other relevant forcings are combined with extrapolated data from meteorological stations and a simplified physically based energy balance model in order to obtain melt-season melt fluxes that are then aggregated to estimate the end-of-winter (or peak) snow water equivalent (SWE). Peak SWE estimates show an overall coefficient of determination R2 of 0.68 and RMSE of 274 mm compared to observations at 12 automatic snow water equivalent sensors distributed across the model domain, with R2 values between 0.32 and 0.88. Regional estimates of peak SWE accumulation show differential patterns strongly modulated by elevation, latitude and position relative to the continental divide. The spatial distribution of peak SWE shows that the 4000–5000 m a.s.l. elevation band is significant for snow accumulation, despite having a smaller surface area than the 3000–4000 m a.s.l. band. On average, maximum snow accumulation is observed in early September in the western Andes, and in early October on the eastern side of the continental divide. The results presented here have the potential of informing applications such as seasonal forecast model assessment and improvement, regional climate model validation, as well as evaluation of observational networks and water resource infrastructure development.
Platform to develop exhaust gas sensors manufactured by glass-solder-supported joining of sintered yttria-stabilized zirconia
Authors: Schubert F. , Wollenhaupt S. , Kita J. , Hagen G. , Moos R. 
Published: January 2016

Abstract. A manufacturing process for a planar binary lambda sensor is shown. By joining the heating and the sensing components via glass soldering with a joining temperature of 850 °C, a laboratory platform has been established that allows the manufacturing of two independent parts in high-temperature co-fired ceramics technology (HTCC) with electrodes that are post-processed at lower temperatures, as is required for mixed-potential sensors. The final device is compared to a commercial sensor with respect to its sensing performance. Important processes and possible origins of problems as well as their solutions during sensor development are shown, including heater design and joining process.
An approach to build an event set of European windstorms based on ECMWF EPS
Authors: Osinski R. , Lorenz P. , Kruschke T. , Voigt M. , Ulbrich U. , Leckebusch G. C. , Faust E. , Hofherr T. , Majewski D. 
Published: January 2016

Abstract. The properties of European windstorms under present climate conditions are estimated on the basis of surface wind forecasts from the European Centre for Medium-Range Weather Forecast (ECMWF) Ensemble Prediction System (EPS). While the EPS is designed to provide forecast information of the range of possible weather developments starting from the observed state of weather, we use its archive in a climatological context. It provides a large number of modifications of observed storm events and includes storms that did not occur in reality. Thus it is possible to create a large sample of storm events, which entirely originate from a physically consistent model, whose ensemble spread represents feasible alternative storm realizations of the covered period. This paper shows that the huge amount of identifiable events in the EPS is applicable to reduce uncertainties in a wide range of fields of research focusing on winter storms. Windstorms are identified and tracked in this study over their lifetime using an algorithm based on the local exceedance of the 98th percentile of instantaneous 10 m wind speed, which is associated with a storm severity measure. After removing inhomogeneities in the data set arising from major modifications of the operational system, the distributions of storm severity, storm size, and storm duration are computed. The overall principal properties of the homogenized EPS storm data set are in good agreement with storms from the ERA-Interim data set, making it suitable for climatological investigations of these extreme events. A demonstrated benefit in the climatological context by the EPS is presented. It gives clear evidence of a linear increase of maximum storm intensity and wind field size with storm duration. This relation is not recognizable from a sparse ERA-Interim sample for long-lasting events, as the number of events in the reanalysis is not sufficient to represent these characteristics.
The Civitavecchia Coastal Environment Monitoring System (C-CEMS): a new tool to analyze the conflicts between coastal pressures and sensitivity areas
Authors: Bonamano S. , Piermattei V. , Madonia A. , Paladini de Mendoza F. , Pierattini A. , Martellucci R. , Stefanì C. , Zappalà G. , Caruso G. , Marcelli M. 
Published: January 2016

Abstract. The understanding of the coastal environment is fundamental for efficiently and effectively facing the pollution phenomena as expected by the Marine Strategy Framework Directive, and for limiting the conflicts between anthropic activities and sensitivity areas, as stated by Maritime Spatial Planning Directive. To address this, the Laboratory of Experimental Oceanology and Marine Ecology developed a multi-platform observing network that has been in operation since 2005 in the coastal marine area of Civitavecchia (Latium, Italy) where multiple uses and high ecological values closely coexist. The Civitavecchia Coastal Environment Monitoring System (C-CEMS), implemented in the current configuration, includes various components allowing one to analyze the coastal conflicts by an ecosystem-based approach. The long-term observations acquired by the fixed stations are integrated with in situ data collected for the analysis of the physical, chemical and biological parameters of the water column, sea bottom and pollution sources detected along the coast. The in situ data, integrated with satellite observations (e.g., temperature, chlorophyll a and TSM), are used to feed and validate the numerical models, which allow the analysis and forecasting of the dynamics of pollutant dispersion under different conditions. To test the potential capabilities of C-CEMS, two case studies are reported here: (1) the analysis of fecal bacteria dispersion for bathing water quality assessment, and (2) the evaluation of the effects of the dredged activities on Posidonia meadows, which make up most of the two sites of community importance located along the Civitavecchia coastal zone. The simulation outputs are overlapped by the thematic maps showing bathing areas and Posidonia oceanica distribution, thus giving a first practical tool that could improve the resolution of the conflicts between coastal uses (in terms of stress produced by anthropic activities) and sensitivity areas.
Utilisation of CryoSat-2 SAR altimeter in operational ice charting
Authors: Rinne E. , Similä M. 
Published: January 2016

Abstract. We present methods to utilise CryoSat-2 (CS-2) synthetic aperture radar (SAR) mode data in operational ice charting. We compare CS-2 data qualitatively to SAR mosaics over the Barents and Kara seas. Furthermore, we compare the CS-2 to archived operational ice charts. We present distributions of four CS-2 waveform parameters for different ice types as presented in the ice charts. We go on to present an automatic classification method for CS-2 data which, after training with operational ice charts, is capable of determining open ocean from ice with a hit rate of  >  90 %. The training data are dynamically updated every 5 days using the most recent 15 days of CS-2 data and operative ice charts. This helps the adaption of the classifier to the evolving ice/snow conditions throughout winter. The classifier is also capable of detecting three different ice classes (thin and thick first-year ice as well as old ice) with success rates good enough for the output to be usable to support operational ice charting. Finally, we present a near-real-time CS-2 product just plotting the waveform characteristics and conclude that even such a simple product is usable for some of the needs of ice charting.
Estimating supraglacial lake depth in West Greenland using Landsat 8 and comparison with other multispectral methods
Authors: Pope A. , Scambos T. A. , Moussavi M. , Tedesco M. , Willis M. , Shean D. , Grigsby S. 
Published: January 2016

Abstract. Liquid water stored on the surface of ice sheets and glaciers impacts surface mass balance, ice dynamics, and heat transport. Multispectral remote sensing can be used to detect supraglacial lakes and estimate their depth and area. In this study, we use in situ spectral and bathymetric data to assess lake depth retrieval using the recently launched Landsat 8 Operational Land Imager (OLI). We also extend our analysis to other multispectral sensors to evaluate their performance with similar methods. Digital elevation models derived from WorldView stereo imagery (pre-lake filling and post-drainage) are used to validate spectrally derived depths, combined with a lake edge determination from imagery. The optimal supraglacial lake depth retrieval is a physically based single-band model applied to two OLI bands independently (red and panchromatic) that are then averaged together. When OLI- and WorldView-derived depths are differenced, they yield a mean and standard deviation of 0.0 ± 1.6 m. This method is then applied to OLI data for the Sermeq Kujalleq (Jakobshavn Isbræ) region of Greenland to study the spatial and intra-seasonal variability of supraglacial lakes during summer 2014. We also give coefficients for estimating supraglacial lake depth using a similar method with other multispectral sensors.
Do Farmers’ Asset Values Correlate with Land Quality?
Authors: Sonneveld Ben G.J.S. , Bunning Sally , Biancalani Riccardo , Ndiaye D. , Nachtergaele Freddy 
Published: January 2016

<p>This paper investigates if farmers’ asset values have a predictive power to asses land quality. A rich sustainable livelihood literature describes small farmers’ biophysical and socio-economic environment through asset values, which closely adheres to the required information for an integrated quality appraisal of the natural resource base. For our analysis we use an in-depth survey held among 50 famers’ households in three rural areas of Senegal. Farmers gave scores for their livelihood assets (human, physical, natural, financial and social) and judgments on the state and trend of the quality of their natural resource base (crop land, rangeland, forest and water resources). As our observational data are dominated by unobserved heterogeneity, we refrain from causal statistical analysis and seek associative patterns between asset values and state and trend of natural resource quality using data visualization techniques and descriptive statistics. We compare categorical data on state and trend of land qualities with asset value classes in a frequency distributions evaluation (Chi-square) and with continuous asset value scores in an analysis of variance (ANOVA). For state of forest we found consistent but counterintuitive differences for various asset values with higher asset values for ‘degraded’ classes and lower values for ‘good’ quality of the forests. There is some evidence that trend of forest quality can be derived from asset value scores which were in agreement with our premise of lower scores for low quality and higher scores for better quality. Yet, overall we have to conclude that asset values do not correlate straightforward and unequivocally with state and trend of natural resource quality. </p>
A Simple Method for Labeling Human Embryonic Stem Cells Destined to Lose Undifferentiated Potency
Authors: Kumagai Ayako , Suga Mika , Yanagihara Kana , Itoh Yumi , Takemori Hiroshi , Furue Miho K. 
Published: January 2016

Abstract

Mitochondrial oxidative phosphorylation is a major source of cellular ATP. Its usage as an energy source varies, not only according to the extracellular environment, but also during development and differentiation, as indicated by the reported changes in the flux ratio of glycolysis to oxidative phosphorylation during embryonic stem (ES) cell differentiation. The fluorescent probe JC-1 allows visualization of changes in the mitochondrial membrane potential produced by oxidative phosphorylation. Strong JC-1 signals were localized in the differentiated cells located at the edge of H9 ES colonies that expressed vimentin, an early differentiation maker. The JC-1 signals were further intensified when individual adjacent colonies were in contact with each other. Time-lapse analyses revealed that JC-1-labeled H9 cells under an overconfluent condition were highly differentiated after subculture, suggesting that monitoring oxidative phosphorylation in live cells might facilitate the prediction of induced pluripotent stem cells, as well as ES cells, that are destined to lose their undifferentiated potency.

Significance
Skillful cell manipulation is a major factor in both maintaining and disrupting the undifferentiation potency of human embryonic stem (hES) cells. Staining with JC-1, a mitochondrial membrane potential probe, is a simple monitoring method that can be used to predict embryonic stem cell quality under live conditions, which might help ensure the future use of hES and human induced pluripotent stem cells after subculture.
High-sensitivity pesticide detection using particle-enhanced resonant Raman scattering
Authors: Ranjan Bikas , Saito Yuika , Verma Prabhat 
Published: January 2016

Abstract
The use of pesticides in agriculture has raised concerns, as even a small residual of pesticide on food can be harmful. It is therefore of great importance to develop a robust technique to detect tiny amounts of pesticides. Although Raman spectroscopy is frequently used for chemical identification, it is not suitable for extremely low molecular concentrations. We propose a technique called particle-enhanced resonant Raman spectroscopy to detect extremely low concentrations of pesticides, where gold nanoparticles of desired plasmonic resonance are synthesized to match the resonance in Raman scattering. We successfully demonstrated the detection of extremely low amounts of pesticides on oranges.
Effect of molecular ordering in active layer on organic thin-film transistor performance
Authors: Kano Masataka , Minari Takeo , Marumoto Kazuhiro 
Published: January 2016

Abstract
We investigate the effect of molecular ordering in the semiconductor of inverted staggered-type organic thin-film transistors (OTFTs) on device parameters. Molecular ordering is controlled by modifying the gate insulator with self-assembled monolayers and clarified by X-ray diffraction analysis. The reduction in the density of free carriers in a semiconductor with the alkyl-modified surface reduces off-current (I
OFF) and increases contact resistance (R
C). In contrast, I
OFF increases and R
C decreases for a phenyl-modified surface. Ultraviolet photoemission studies revealed that differences in the molecular ordering and the surface dipole moment caused by the insulator surfaces are crucial for device parameters for OTFTs.
Strain energy analysis of screw dislocations in 4H-SiC by molecular dynamics
Authors: Kawamura Takahiro , Mizutani Mitsutoshi , Suzuki Yasuyuki , Kangawa Yoshihiro , Kakimoto Koichi 
Published: January 2016

Abstract
We simulated screw dislocations with the Burgers vector parallel to the [0001] direction in 4H-SiC by a classical molecular dynamics method. A stable structure of an extended dislocation generated by the dissociation of a screw dislocation was identified by calculating the strain energy caused by dislocation cores and stacking faults. As a result, we conclude that the most expected structure of the extended dislocation is made of partial dislocations with the Burgers vector b = 1/2c + 1/2c (c is equal to the thickness of one period in the c-axis direction of 4H-SiC) and the stacking fault that is parallel to the a-plane, and that the distance between the dislocation cores is less than about 44 Å.
Parabolic refractive X-ray lenses made of quartz glass for high-energy X-ray focusing
Authors: Kimura Shigeru , Imai Yasuhiko 
Published: January 2016

Abstract
We have fabricated planar parabolic refractive X-ray lenses made of quartz glass for high-energy X-ray focusing by optical lithography and dry etching techniques. We succeeded in 100-µm-deep etching, realizing highly efficient microfocusing for high-energy X-rays. We measured the size and photon flux of the X-rays focused by two lenses with a crossed geometry at BL13XU of SPring-8. High-flux (more than 2 × 109 photons/s) microbeams with 25 and 30 keV X-rays were successfully obtained.