Search results for "solution"

Deciliation: A stressful event for Paracentrotus lividus embryos.

1998

In this report, by using mono- and two-dimensional electrophoretic analysis, we demonstrate that deciliation on sea urchin embryos induces a stress response. Deciliation indeed causes not only the activation of ciliary subroutine, but also a transient decrease of bulk protein synthesis. This decrease is in agreement with our previous results on heat shock response in sea urchin, although deciliation does not induce the expression of the same main hsp set. We were able to characterize one main deciliation-stress protein of 40 kDa whose expression is transiently induced by deciliation and whose localisation is likely to be nuclear.

High Reynolds number Navier-Stokes solutions and boundary layer separation induced by a rectilinear vortex

2013

Abstract We compute the solutions of Prandtl’s and Navier–Stokes equations for the two dimensional flow induced by a rectilinear vortex interacting with a boundary in the half plane. For this initial datum Prandtl’s equation develops, in a finite time, a separation singularity. We investigate the different stages of unsteady separation for Navier–Stokes solution at different Reynolds numbers Re = 103–105, and we show the presence of a large-scale interaction between the viscous boundary layer and the inviscid outer flow. We also see a subsequent stage, characterized by the presence of a small-scale interaction, which is visible only for moderate-high Re numbers Re = 104–105. We also investi…

Structure and Deformations of Pd−Ni Core−Shell Nanoparticles

2005

International audience; Homogeneous collections of Pd−Ni core−shell nanoparticles have been prepared by decomposition of metal−organic compounds and studied by several electron microscopy techniques: transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), high-resolution transmission electron microscopy (HRTEM), energy-filtered microscopy (EFTEM), and by X-ray photoelectron spectroscopy (XPS). The physical and chemical properties of the Pd shell are supposed to depend on its electronic properties, which are influenced by the presence of the Ni core and by the deformation in the Pd lattice. Here, the interfacial structure of Pd/Ni and the lattice deformations in t…

Cascade complex formation by phosphate in the cobalt(II)/[30]aneN10 anaerobic system

1993

Abstract The interaction of phosphate with the mono- and binuclear cobalt(II) complexes of [30]aneN 10 (1,4,7,10,13,16,19,22,25,28-decaazacyclotriacontane) has been studied by potentiometry in 0.15 mol dm −3 NaClO 4 solution at 298.15 K under anaerobic conditions. The stable species [CoH 2 ([30]aneN 10 )PO 4 ] + , [CoH 4 ([30]aneN 10 )PO 4 ] 3+ , [Co 2 H([30]aneN 10 )PO 4 ] 2+ , [Co 2 H 2 ([30]aneN 10 )PO 4 ] 3+ and [Co 2 H 3 ([30]aneN 10 )PO 4 ] 4+ , where the phosphate anion is directly bound to the metal ions or acts as a second sphere ligand, are formed and their stability constants have been determined. The results obtained allowed for the selection of suitable conditions for the study…

Single molecule localization microscopy of the distribution of chromatin using Hoechst and DAPI fluorescent probes.

2014

Several approaches have been described to fluorescently label and image DNA and chromatin in situ on the single-molecule level. These superresolution microscopy techniques are based on detecting optically isolated, fluorescently tagged anti-histone antibodies, fluorescently labeled DNA precursor analogs, or fluorescent dyes bound to DNA. Presently they suffer from various drawbacks such as low labeling efficiency or interference with DNA structure. In this report, we demonstrate that DNA minor groove binding dyes, such as Hoechst 33258, Hoechst 33342, and DAPI, can be effectively employed in single molecule localization microscopy (SMLM) with high optical and structural resolution. Upon ill…

Replication origins and pause sites in sea urchin mitochondrial DNA

1992

We have used a combination of one- and two-dimensional agarose gel electrophoresis, and solution hybridization to strand-specific probes, to map the replication origin of sea urchin mitochondrial DNA and to investigate the structure of replication intermediates. These assays are consistent with replication initiating unidirectionally from the D-loop region by D-loop expansion, as in vertebrates. A prominent site of initiation of lagging-strand synthesis lies at, or near to, the boundary between the genes for ATPase 6 and COIII, which is also close to a pause site for leading-strand synthesis. These findings suggest a role for pause sites in the regulation of mitochondrial transcription and …

2019

From the very beginnings of radiotherapy, a crucial question persists with how to target the radiation effectiveness into the tumor while preserving surrounding tissues as undamaged as possible. One promising approach is to selectively pre-sensitize tumor cells by metallic nanoparticles. However, though the “physics” behind nanoparticle-mediated radio-interaction has been well elaborated, practical applications in medicine remain challenging and often disappointing because of limited knowledge on biological mechanisms leading to cell damage enhancement and eventually cell death. In the present study, we analyzed the influence of different nanoparticle materials (platinum (Pt), and gold (Au)…

Résolution spatiale des MNT et qualité de l'estimation des températures et des précipitations en France

2015

DTM spatial resolution and temperature and amount of rainfall estimation in France. The spatial variationanalysis of normal temperature and amount of rainfall in France is performed by simple linear correlations where elevationis the explanatory variable. The latter is provided in seven resolutions: 250,500 m, 1, 2, 4, 8 and 16 km. The correlationcoefficient is used to assess what is the resolution that works best. Temperatures are optimally explained by the 250 mresolution, the coarser resolutions producing lower quality results. The 2km resolution best explains the spatial variation ofrainfall.

Hirālu piridīna organokatalizatoru izstrāde un pielietojums

2015

Maģistra darba ietvaros tika izstrādāta hirālu DMAP organokatalizatoru sintēze. Iegūto organokatalizatoru aktivitāte tika pārbaudīta tetrazola hemiaminālu dinamiskajā kinētiskajā sadalīšanā.

Analysis of the linkages between rainfall and land surface conditions in the West African monsoon through CMAP, ERS-WSC, and NOAA-AVHRR data

2005

International audience; The European Remote Sensing Wind Scatterometer (ERS-WSC) backscattering coefficient, NOAA Advanced Very High Resolution Radiometer (NOAA-AVHRR) Normalized Difference Vegetation Index (NDVI), and Climate Prediction Center Merged Analysis Precipitation ( CMAP) precipitation data sets are studied over the period August 1991 to December 2000 to document ( 1) the interannual and intra-annual evolutions of vegetation photosynthetic activity and soil-vegetation water content over West Africa and ( 2) their two-way links with precipitation. Over the Sahel, at interannual timescales the strongest relationships between vegetation, soil moisture, and precipitation are observed …