Search results for "LM"
showing 10 items of 19289 documents
Finländska svensklärares undervisningspraktiker och deras samband med elevers inlärningsresultat
2019
Lärarens val av undervisningspraktiker spelar en avgörande roll för elevers inlärningsresultat. I lärarkognitionen ingår förmågan att på adekvata sätt styra och handleda elevens inlärningsprocess och utvärdera dess utgång med livslångt lärande som huvudsyfte. I artikeln kartläggs och analyseras vilka samband som finns mellan undervisningspraktiker och elevers inlärningsresultat i svenskans långa lärokurs i slutet av den grundläggande utbildningen. Materialsamplet härstammar från den finländska nationella utvärderingen från 2013 och omfattar 1679 elever och 98 lärare, vars respons genomgick en fördjupad analys. Ur analysen framgick en tämligen traditionell bild av lärarnas arbetssätt. Vissa …
STANCE BUNDLES IN ENGLISH-TO-POLISH TRANSLATION: A CORPUS-INFORMED STUDY
2018
In this paper, we make an attempt to improve the textual fit of English-to-Polish translation of a peculiar type of multi-word units known in corpus linguistic literature as lexical bundles (Biber et al. 1999). Inspired by a study conducted by Grabar and Lefer (2015), we used the English-Polish parallel corpus Paralela (Pezik 2016) and the National Corpus of Polish (NKJP) to extract and explore the use - in terms of frequency distributions - of the Polish equivalents of selected English lexical bundles expressing attitudinal and epistemic stance. More precisely, we used the NKJP corpus to check whether the Polish equivalents are typical of contemporary Polish as found in native texts. The r…
Spontaneous domain formation of phospholipase A2 at interfaces: fluorescence microscopy of the interaction of phospholipase A2 with mixed monolayers …
1992
Abstract Fluorescence microscopy has recently been proven to be an ideal tool to investigated the specific interaction of phospholipase A 2 with oriented substrate monolayers. Using a dual labeling technique, it could be shown that phospholipase A 2 can specifically attack and hydrolyze solid analogous l -α-DPPC domains. After a critical extent of monolayer hydrolysis the enzyme itself starts to aggregate forming regular shaped protein domains (Grainger et al. (1990) Biochim. Biophys. Acta 1023. 365–379). In order to confirm that the existence of hydrolysis products in the mononlayer is necessary for the observed aggregation of phospholipase A 2 , mixed monolayers of d - and l -α-DPPC, l -α…
Stability of Asymmetric Lipid Bilayers Assessed by Molecular Dynamics Simulations
2009
The asymmetric insertion of amphiphiles into biological membranes compromises the balance between the inner and outer monolayers. As a result, area expansion of the receiving leaflet and curvature strain may lead to membrane permeation, shape changes, or membrane fusion events. We have conducted both atomistic and coarse-grained molecular dynamics simulations of dipalmitoyl-phosphatidylcholine (DPPC) bilayers to study the effect of an asymmetric distribution of lipids between the two monolayers on membrane stability. Highly asymmetric lipid bilayers were found to be surprisingly stable within the submicrosecond time span of the simulations. Even the limiting case of a monolayer immersed in …
AFM study of interaction forces in supported planar DPPC bilayers in the presence of general anesthetic halothane
2006
International audience; In spite of numerous investigations, the molecular mechanism of general anesthetics action is still not well understood. It has been shown that the anesthetic potency is related to the ability of an anesthetic to partition into the membrane. We have investigated changes in structure, dynamics and forces of interaction in supported dipalmitoylphosphatidylcholine (DPPC) bilayers in the presence of the general anesthetic halothane. In the present study, we measured the forces of interaction between the probe and the bilayer using an atomic force microscope. The changes in force curves as a function of anesthetic incorporation were analyzed. Force measurements were in go…
Direct Observation of Nanometer-Scale Pores of Melittin in Supported Lipid Monolayers
2015
Melittin is the most studied membrane-active peptide and archetype within a large and diverse group of pore formers. However, the molecular characteristics of melittin pores remain largely unknown. Herein, we show by atomic force microscopy (AFM) that lipid monolayers in the presence of melittin are decorated with numerous regularly shaped circular pores that can be distinguished from nonspecific monolayer defects. The specificity of these pores is reinforced through a statistical evaluation of depressions found in Langmuir-Blodgett monolayers in the presence and absence of melittin, which eventually allows characterization of the melittin-induced pores at a quantitative low-resolution leve…
Parvovirus capsid disorders cholesterol-rich membranes.
2008
In this study canine parvovirus, CPV, was found to induce disorder in DPPC:cholesterol membranes in acidic conditions. This acidicity-induced fluidizing effect is suggested to originate from the N-terminus of the viral capsid protein VP1. In accordance with the model membrane studies, a fluidizing effect was seen also in the endosomal membranes during CPV infection implying an important functional role of the fluidization in the endocytic entry of the virus.
Partition of Indicaxanthin in Membrane Biomimetic Systems. A Kinetic and Modeling Approach
2009
The solubilization site of indicaxanthin (Ind) in lipid bilayers was investigated by the kinetics of Ind oxidation by peroxyl radicals in water and in aqueous/L-alpha-dipalmitoyl-phosphatidylcholine (DPPC) vesicles, pH 7.4, and 37.0 and 48.0 degrees C, that is, in a gel-like and a crystal liquidlike bilayer state, respectively. The time-dependent Ind absorbance decay, matched with a successful simulation of the reaction kinetic mechanism by Gepasi software, supported a multistep pathway. Computer-assisted analysis allowed calculation of the rate constants associated with the reactions involved, the values of which decreased with increasing DPPC concentration. The binding constant calculated…
The influence of tin compounds on the dynamic properties of liposome membranes: A study using the ESR method
2005
AbstractThe influence of organic and inorganic compounds of tin on the dynamic properties of liposome membranes obtained in the process of dipalmitoylphosphatidylcholine (DPPC) sonication in distilled water was investigated. This was carried out by means of the spin ESR probe method. The probes were selected in such a way as to penetrate different areas of the membrane (a TEMPO probe, 5-DOXYL stearic acid, 16-DOXYL stearic acid). Four compounds of tin were chosen: three organic ones, (CH3)4Sn, (C2H5)4Sn and (C3H7)3SnCl, and one inorganic one, SnCl2. The investigated compounds were added to a liposome dispersion, which was prepared prior to that. The concentration of the admixture was change…
CCDC 986491: Experimental Crystal Structure Determination
2014
Related Article: Albert Ferrer-Ugalde, Arántzazu González-Campo, Clara Viñas, Jesús Rodríguez-Romero, Rosa Santillan, Norberto Farfán, Reijo Sillanpää, Antonio Sousa-Pedrares, Rosario Núñez, Francesc Teixidor|2014|Chem.-Eur.J.|20|9940|doi:10.1002/chem.201402396