Search results for "gradient"
showing 10 items of 725 documents
Single-pump heart-cutting two-dimensional liquid chromatography applied to the determination of fatty alcohol ethoxylates.
2014
Abstract A setup for heart-cutting bi-dimensional liquid chromatography (LC–LC), constructed with a chromatograph provided with a single pump, an auxiliary 6-port 2-position valve (V 6/2 ) and a column selector valve (V CS ), is described. The possible ways of connecting the two valves for LC–LC, namely with V 6/2 first followed by V CS and vice versa, are compared. The possibility of using the setups for preconcentration followed by the backwards transfer of the preconcentrated solutes to the detector or to a second column is also shown. The V 6/2 -first configuration for LC–LC was applied to the characterization of industrial fatty alcohol ethoxylates (FAEs) using UV–vis detection. For th…
Temporal species turnover and plant community changes across different habitats in the Lake Engure Nature Park, Latvia
2014
Veģetācijas dinamikas izpētē reti ir gadījumi, kad monitoringu vienlaicīgi veic vairākās atšķirīgās ekosistēmās. Tomēr šāda veida pētījumi ļauj padziļināti izprast veģetācijas struktūras un pazīmju izmaiņu mehānismus. Šajā pētījumā aplūkotas lakstaugu stāva izmaiņas, sugu aprite un sugu skaita-laika attiecība dažādu biotopu griezumā 12 gadu periodā ILTER monitoringa stacijā Engures ezera dabas parkā. Sugu aprite laikā definēta kā atšķirība sugu sastāvā starp diviem laika periodiem. Sugu skaita-laika attiecība tika novērtēta, izmantojot slīdošo logu pieeju. Detrendētā korespondentanalīze izmantota, lai noskaidrotu ikgadējās izmaiņas sugu sastāvā. Sugu skaits un kumulatīvais skaits, kā arī da…
Orientation of the electric field gradient and ellipticity of the magnetic cycloid in multiferroic BiFeO3
2016
This work was supported by Uniwersytet Pedagogiczny.
POPOLAMENTI MARGINALI DI FAGGIO E CAMBIAMENTI CLIMATICI IN SICILIA: CRITICITÀ ED EFFETTI DELL’APPLICAZIONE DI PRATICHE SELVICOLTURALI TRADIZIONALI NO…
2016
Il faggio (Fagus sylvatica) è una tipica specie medio-Europea; in Sicilia si rinvengono i boschi di faggio più meridionali d’Europa. La marginalità ecologica di questi boschi è particolarmente evidente nei pattern frammentati e isolati di questi soprassuoli, in prossimità del limite della vegetazione arborea e/o localizzati nelle condizioni topografiche meno favorevoli. Nel presente lavoro si mettono a confronto i parametri dendrometricostrutturali e lo stato di salute delle piante in soprassuoli delle Madonie, confrontando cedui di faggio recentemente sottoposti a pratiche di taglio e aree di controllo non trattate da tempo. Inoltre, questi aspetti sono stati messi in relazione con il grad…
La genètica de les migracions humanes: Seguint el rastre de les migracions a través del nostre genoma
2014
La reconstruccio de les migracions humanes es possible gracies a la informacio aportada per diverses disciplines. L’estudi de la diversitat genetica de les poblacions humanes actuals ens revela quins han estat els esdeveniments demografics i moviments migratoris passats que han deixat una empremta en el nostre genoma. El coneixement dels moviments migratoris en temps prehistorics ens permet comprovar hipotesis proposades des d’altres disciplines cientifiques. De la mateixa manera, la distribucio de la diversitat genetica en el futur dependra, en gran part, de les intenses migracions humanes actuals facilitades pels avencos tecnologics.
Mapping a-priori defined plant associations using remotely sensed vegetation characteristics
2014
Abstract Incorporation of a priori defined plant associations into remote sensing products is a major challenge that has only recently been confronted by the remote sensing community. We present an approach to map the spatial distribution of such associations by using plant indicator values (IVs) for salinity, moisture and nutrients as an intermediate between spectral reflectance and association occurrences. For a 12 km 2 study site in the Netherlands, the relations between observed IVs at local vegetation plots and visible and near-infrared (VNIR) and short-wave infrared (SWIR) airborne reflectance data were modelled using Gaussian Process Regression (GPR) (R 2 0.73, 0.64 and 0.76 for sali…
Effect of digitonin on membrane-bound and chitosomal chitin synthetase activity in protoplasts from yeast cells ofCandida albicans
1993
The effect of digitonin on chitin synthetase present in membrane (MMF) and cytoplasmic fractions (chitosomes) (CF) from C. albicans yeast protoplasts has been determined. The zymogen is preferentially, but not exclusively, solubilized by digitonin from MMF. Centrifugation of distinct solubilized preparations, containing either zymogen, in vivo active enzyme and/or trypsin activated enzyme, on linear sucrose gradients suggests that both zymogen and trypsin activated enzyme sediment slightly slower than the active enzyme, pointing out differences between the activation processes in vivo and in vitro or, alternatively, that both enzyme activities (active in vivo and zymogenic) correspond to di…
Distance decay 2.0. A global synthesis of taxonomic and functional turnover in ecological communities
2022
Caio Graco-Roza was funded by the Coordination for the Improvement of Higher Education Personnel (CAPES), the Carlos Chagas Filho Research Support Foundation (FAPERJ) and the Ella and Georg Erhnrooth Foundation; Jan Altman by research grants INTER-EXCELLENCE LTAUSA19137 provided by Czech Ministry of Education, Youth and Sports, 20-05840Y of the Czech Science Foundation, and long-term research development project no. RVO 67985939 of the Czech Academy of Sciences; Otso Ovaskainen was funded by Academy of Finland (grant no. 309581), Jane and Aatos Erkko Foundation, Research Council of Norway through its Centres of Excellence Funding Scheme (223257), and the European Research Council (ERC) unde…
High‐resolution 3D forest structure explains ecomorphological trait variation in assemblages of saproxylic beetles
2022
1. Climate, topography and the 3D structure of forests are major drivers affecting local species communities. However, little is known about how the specific functional traits of saproxylic (wood-living) beetles, involved in the recycling of wood, might be affected by those environmental characteristics. 2. Here, we combine ecological and morphological traits available for saproxylic beetles and airborne laser scanning (ALS) data in Bayesian trait-based joint species distribution models to study how traits drive the distributions of more than 230 species in temperate forests of Europe. 3. We found that elevation (as a proxy for temperature and precipitation) and the proportion of conifers p…
Mantle-derived fluids discharged at the Bradanic foredeep/Apulian foreland boundary: The Maschito geothermal gas emissions (southern Italy)
2014
Abstract The mephitis of Maschito, known since historical times as Lago Fetente (Smelly Lake) -although the lake is now dry-, is located 20 km from the Mt. Vulture volcanic edifice (Southern Italy). It is placed along the same regional tectonic discontinuity where some maars are located, close to the boundary between the foredeep and the Apulian foreland. About 300 m2 of surface is lacking in flora, while dead animals are frequently found all around it. The smelly exhalations are mainly composed of CO2 (∼98%), and, in lesser amounts, of H2S, N2, CH4 and other hydrocarbons. He, Ne and Ar occur in trace amounts. The CO2 isotopic composition is in the range of that of the main active Italian v…