400 research outputs found
NO2 jet cooled visible excitation spectrum - Vibronic chaos induced by the X2A1-A2B2 interaction
International audienceSignificant improvements have been obtained on measurements of the NO2 jet cooled excitation spectrum in the 16 300-18 502 cm-1 range, previously obtained by Smalley et al. [J. Chem. Phys. 63,4977 ( 1975), Persch et al. [ Ber. Bunsenges. Phys. Chem. 92,312 ( 1988), and Hiraoka et al. [J. Mol. Spectrosc. 126,427 ( 1987). The improvements concern first the rotational analysis, owing to a better resolution ( 150 MHz) and absolute precision ( 500 MHz), and second the completeness and purity of the resulting vibronic sequence, owing to a better sensitivity. As a result, 159 vibronic energy levels have been observed in the 16 500-18 500 cm-1 energy range, where 210 ± 10 are expected. A detailed comparison with previous results is presented. The statistical analysis of the corresponding energy spacings shows that long range correlations up to 50 mean levels spacings are present, confirming the chaotic behavior of this set of vibronic levels. Furthermore, we analyze the observed rovibronic interactions (or rotational perturbations) that are responsible for the very irregular rotational behavior of the visible absorption spectrum of NO2 at room temperature
Minimum-weight perfect matching for non-intrinsic distances on the line
Consider a real line equipped with a (not necessarily intrinsic) distance. We
deal with the minimum-weight perfect matching problem for a complete graph
whose points are located on the line and whose edges have weights equal to
distances along the line. This problem is closely related to one-dimensional
Monge-Kantorovich trasnport optimization. The main result of the present note
is a "bottom-up" recursion relation for weights of partial minimum-weight
matchings.Comment: 13 pages, figures in TiKZ, uses xcolor package; introduction and the
concluding section have been expande
Iklim Organisasi, Stres Kerja, Dan Kepuasan Kerja Pada Perawat
The aim of this study is to measure contribution of organizational climate and job stress towork satisfaction. The participants of this research are 150 nurses from hospital in EastJakarta. Multiple regression is used for the data analysis. The data is collected by giving thequestionairre to the participants. The result shows that organizational climate hascontribution score around 8.5% to work satisfaction. On the other side, job stress contributesaround 7.2% to work satisfaction. Furthermore, organizational climate and job stresscontribute around 14.7% to work satisfaction simultaneously
Multi-confocal fluorescence correlation spectroscopy in living cells using a complementary metal oxide semiconductor-single photon avalanche diode array
International audienceLiving cells are heterogeneous and rapidly changing biological samples. It is thus desirable to measure molecular concentration and dynamics in many locations at the same time. In this note, we present a multi-confocal setup capable of performing simultaneous fluorescence correlation spectroscopy measurements, by focusing the spots with a spatial light modulator and acquiring data with a monolithic 32 Ă 32 single-photon avalanche photodiode array. A post-processing method is proposed to correct cross-talk effects between neighboring spots. We demonstrate the applicability of our system by simultaneously measuring the diffusion of free enhanced Green Fluorescent Protein (eGFP) molecules at nine different points in living cells
Dry deposition of nitrogen compounds (NO 2 , HNO 3 , NH 3 ), sulfur dioxide and ozone in west and central African ecosystems using the inferential method
Abstract. This work is part of the IDAF program (IGAC-DEBITS-AFRICA) and is based on the long-term monitoring of gas concentrations (1998â2007) established at seven remote sites representative of major African ecosystems. Dry deposition fluxes were estimated by the inferential method using on the one hand surface measurements of gas concentrations (NO2, HNO3, NH3, SO2 and O3) and on the other hand modeled exchange rates. Dry deposition velocities (Vd) were calculated using the big-leaf model of Zhang et al. (2003b). The bidirectional approach is used for NH3 surfaceâatmosphere exchange (Zhang et al., 2010). Surface and meteorological conditions specific to IDAF sites have been used in the models of deposition. The seasonal and annual mean variations of gaseous dry deposition fluxes (NO2, HNO3, NH3, O3 and SO2) are analyzed. Along the latitudinal transect of ecosystems, the annual mean dry deposition fluxes of nitrogen compounds range from â0.4 to â0.8 kg N haâ1 yrâ1 for NO2, from â0.7 to â1.0 kg N haâ1 yrâ1 for HNO3 and from â0.7 to â8.3 kg N haâ1 yrâ1 for NH3 over the study period (1998â2007). The total nitrogen dry deposition flux (NO2+HNO3+NH3) is more important in forests (â10 kg N haâ1 yrâ1) than in wet and dry savannas (â1.6 to â3.9 kg N haâ1 yrâ1). The annual mean dry deposition fluxes of ozone range between â11 and â19 kg haâ1 yrâ1 in dry and wet savannas, and â11 and â13 kg haâ1 yrâ1 in forests. Lowest O3 dry deposition fluxes in forests are correlated to low measured O3 concentrations, lower by a factor of 2â3, compared to other ecosystems. Along the ecosystem transect, the annual mean of SO2 dry deposition fluxes presents low values and a small variability (â0.5 to â1 kg S haâ1 yrâ1). No specific trend in the interannual variability of these gaseous dry deposition fluxes is observed over the study period
Analyzing symmetry breaking within a chaotic quantum system via Bayesian inference
Bayesian inference is applied to the level fluctuations of two coupled
microwave billiards in order to extract the coupling strength. The coupled
resonators provide a model of a chaotic quantum system containing two coupled
symmetry classes of levels. The number variance is used to quantify the level
fluctuations as a function of the coupling and to construct the conditional
probability distribution of the data. The prior distribution of the coupling
parameter is obtained from an invariance argument on the entropy of the
posterior distribution.Comment: Example from chaotic dynamics. 8 pages, 7 figures. Submitted to PR
Capturing and Quantifying Particle Transcytosis with Microphysiological Intestine-on-Chip Models
Understanding the intestinal transport of particles is critical in several fields ranging from optimizing drug delivery systems to capturing health risks from the increased presence of nano- and micro-sized particles in human environment. While Caco-2 cell monolayers grown on permeable supports are the traditional in vitro model used to probe intestinal absorption of dis-solved molecules, they fail to recapitulate the transcytotic activity of polar-ized enterocytes. Here, an intestine-on-chip model is combined with in silico modeling to demonstrate that the rate of particle transcytosis is â350Ă higher across Caco-2 cell monolayers exposed to fluid shear stress compared to Caco-2 cells in standard âstaticâ configuration. This relates to profound phe-notypical alterations and highly polarized state of cells grown under mechan-ical stimulation and it is shown that transcytosis in the microphysiological model is energy-dependent and involves both clathrin and macropinocytosis mediated endocytic pathways. Finally, it is demonstrated that the increased rate of transcytosis through cells exposed to flow is explained by a higher rate of internal particle transport (i.e., vesicular cellular trafficking and baso-lateral exocytosis), rather than a change in apical uptake (i.e., binding and endocytosis). Taken together, the findings have important implications for addressing research questions concerning intestinal transport of engineered and environmental particles.Ludivine C. Delon, Matthew Faria, Zhengyang Jia, Stuart Johnston, Rachel Gibson, Clive A. Prestidge, and Benjamin Thierr
Capillary Bridge Formation and Breakage: A Test to Characterize Antiadhesive Surfaces
In order to characterize very weak adhesive surfaces, we have developed a
quantitative test inspired by the Johnson, Kendall, and Roberts adhesion test
for soft adhesives, which relies on the formation and then the rupture of a
capillary bridge between the surface to be tested and a liquid bath. Both the
shape and the kinetics of breakage of the capillary bridge for various coatings
put into contact with liquids of various viscosities and surface tensions have
been studied. Several pull off regimes can be distinguished. For low pull off
velocities, a quasi-static regime is observed, well described by capillary
equations and sensitive to the hysteresis of the contact angle of the fluid on
the coating. Above a critical pull off velocity that depends on the fluid
viscosity, a dynamic regime is observed, characterized by the formation of a
flat pancake of fluid on the coating that recedes more slowly than the
capillary bridge itself. After the breakage of the capillary bridge, a small
drop can remain attached to the surface. The volume of this drop depends on the
dynamical regime and is strongly affected by very small differences between the
coatings. The aptitude of this test in characterizing very weakly adhesive
surfaces is exemplified by a comparison between three different perfluorinated
coatings
Fam65b is a new transcriptional target of FOXO1 that regulates RhoA signaling for T lymphocyte migration
Forkhead box Os (FOXOs) transcription factors favor both T cell quiescence and trafficking through their control of the expression of genes involved in cell cycle progression, adhesion and homing. Here, we report that the product of the fam65b gene is a new transcriptional target of FOXO1 that regulates RhoA activity. We show that Fam65b binds the small GTPase RhoA via a non canonical domain and represses its activity by decreasing its GTP loading. As a consequence, Fam65b negatively regulates chemokine-induced responses such as adhesion, morphological polarisation and migration. Therefore, these results show the existence of a new functional link between FOXO1 and RhoA pathways, through which the FOXO1 target Fam65b tonically dampens chemokine-induced migration by repressing RhoA activity
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