Effect of ascorbic acid on the consequences of acute alcohol consumption in humans

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/109850/1/cptclpt198765.pd

How glassy are orientational dynamics of rodlike molecules near the isotropic-nematic transition?

In an attempt to quantitatively characterize the recently observed slow dynamics in the isotropic and nematic phase of liquid crystals, we investigate the single-particle orientational dynamics of rodlike molecules across the isotropic-nematic transition in computer simulations of a family of model systems of thermotropic liquid crystals. Several remarkable features of glassy dynamics are on display including non-exponential relaxation, dynamical heterogeneity, and non-Arrhenius temperature dependence of the orientational relaxation time. In order to obtain a quantitative measure of glassy dynamics in line with the estbalished methods in supercooled liquids, we construct a relaxation time versus scaled inverse temperature plot, and demonstrate that one can indeed define a 'fragility index' for thermotropic liquid crystals, that depends on density and aspect ratio. The values of the fragility parameter are surprisingly in the range one observed for glass forming liquids. A plausible correlation between the energy landscape features and the observed fragility is discussed.Comment: 7 figures and 8 page

Morphology of the Io Plasma Torus From Juno Radio Occultations

The jovian moon Io disperses about 1 ton/s of material in the planetary magnetosphere, mainly by sublimation of SO2 from the surface and by its intense volcanic activity. The ejected material supplies the plasma cloud surrounding Jupiter known as Io Plasma Torus (IPT). The radio communication between Juno and the Earth DSN station crosses the IPT near the closest approach. Being a dispersive medium, the IPT introduces a path delay in the signal, which can be analyzed to retrieve the density distribution of electrons. We used radio tracking data from the first 25 orbits to investigate the morphology of the IPT and its variability. We adopted a static and axisymmetric model for the electron density and we updated it including temporal and longitudinal variability. We found that our best fit model must include both variabilities, even though on average the morphology of the IPT agrees with previous analyses. Our results suggest that the density of the outer region of the IPT fluctuates over 50% the average value over a typical time scale of about 420 days

Does exist a correlation between endometriosis and thrombophilic disorders? A pilot study

OBJECTIVE: At present, there is growing evidence of the existence of a genetic predisposition in both thrombophilic disorders and endometriosis. The aim of our study was to evaluate for the first time the prevalence of some thrombophilic disorders in patients with endometriosis. MATERIALS AND METHODS: We conducted a retrospective study on 138 patients with endometriosis and 278 healthy control women. All women were subjected to a blood examination testing for thrombophilic screening and the variables examinated were: hyperhomocysteinemia, factor V Leiden and factor II prothrombin G20210A mutations in heterozygosis and homozigosis. RESULTS: A significant reduced prevalence (p < 0.05) of factor V Leiden mutation in endometriosis patients was found, whereas no significant differences (p = NS) for factor II and hyperhomocysteinemia were observed. CONCLUSION: Our preliminary data do not show any association between thrombophilic condition and endometriosis. Before assuming hormonal therapies, a thrombophilic plasmatic screening seems to be unnecessary in patients affected by endometriosis

Critical fluctuations and random-anisotropy glass transition in nematic elastomers

We carry out a detailed deuterium NMR study of local nematic ordering in polydomain nematic elastomers. This system has a close analogy to the random-anisotropy spin glass. We find that, in spite of the quadrupolar nematic symmetry in 3-dimensions requiring a first-order transition, the order parameter in the quenched ``nematic glass'' emerges via a continuous phase transition. In addition, by a careful analysis of the NMR line shape, we deduce that the local director fluctuations grow in a critical manner around the transition point. This could be the experimental evidence for the Aizenman-Wehr theorem about the quenched impurities changing the order of discontinuous transition

TRIS III: the diffuse galactic radio emission at δ=+42∘\delta=+42^{\circ}

We present values of temperature and spectral index of the galactic diffuse radiation measured at 600 and 820 MHz along a 24 hours right ascension circle at declination $\delta = +42^{\circ}$. They have been obtained from a subset of absolute measurements of the sky temperature made with TRIS, an experiment devoted to the measurement of the Cosmic Microwave Background temperature at decimetric-wavelengths with an angular resolution of about $20^{\circ}$. Our analysis confirms the preexisting picture of the galactic diffuse emission at decimetric wavelength and improves the accuracy of the measurable quantities. In particular, the signal coming from the halo has a spectral index in the range $2.9-3.1$ above 600 MHz, depending on the sky position. In the disk, at TRIS angular resolution, the free-free emission accounts for the 11% of the overall signal at 600 MHz and 21% at 1420 MHz. The polarized component of the galactic emission, evaluated from the survey by Brouw and Spoelstra, affects the observations at TRIS angular resolution by less than 3% at 820 MHz and less than 2% at 600 MHz. Within the uncertainties, our determination of the galactic spectral index is practically unaffected by the correction for polarization. Since the overall error budget of the sky temperatures measured by TRIS at 600 MHz, that is 66 mK(systematic)$+$18 mK (statistical), is definitely smaller than those reported in previous measurements at the same frequency, our data have been used to discuss the zero levels of the sky maps at 150, 408, 820 and 1420 MHz in literature. Concerning the 408 MHz survey, limiting our attention to the patch of sky corresponding to the region observed by TRIS, we suggest a correction of the base-level of $(+3.9\pm 0.6)$K.Comment: Accepted for publication in the Astrophysical Journa

Site investigation and modelling at "La Maina" landslide (Carnian Alps, Italy)

International audienceThe Sauris reservoir is a hydroelectric basin closed downstream by a 136 m high, double arc concrete dam. The dam is firmly anchored to a consistent rock (Dolomia dello Schlern), but the Lower Triassic clayey formations, cropping out especially in the lower part of the slopes, have made the whole catchment basin increasingly prone to landslides. In recent years, the "La Maina landslide" has opened up several joints over a surface of about 100 000 m2, displacing about 1 500 000 m3 of material. Particular attention is now being given to the evolution of the instability area, as the reservoir is located at the foot of the landslide. Under the commission of the Regional Authority for Civil Protection a numerical modelling simulation in a pseudo-time condition of the slope was developed, in order to understand the risk for transport infrastructures, for some houses and for the reservoir and to take urgent mesaures to stabilize the slope. A monitoring system consisting of four inclinometers, three wire extensometers and ten GPS bench-mark pillars was immediately set up to check on surface and deep displacements. The data collected and the geological and geomorphological evidences was used to carry out a numerical simulation. The reliability of the results was checked by comparing the model with the morphological evidence of the movement. The mitigation measures were designed and realised following the indications provided by the model

Intra- and interobserver agreement with regard to describing adnexal masses using International Ovarian Tumor Analysis terminology: reproducibility study involving seven observers

To estimate intraobserver repeatability and interobserver agreement in assessing the presence of papillary projections in adnexal masses and in classifying adnexal masses using the International Ovarian Tumor Analysis terminology for ultrasound examiners with different levels of experience. We also aimed to identify ultrasound findings that cause confusion and might be interpreted differently by different observers, and to determine if repeatability and agreement change after consensus has been reached on how to interpret 'problematic' ultrasound images

Varying chiral ratio of Pinic acid enantiomers above the Amazon rainforest

Chiral chemodiversity plays a crucial role in biochemical processes such as insect and plant communication. However, the vast majority of organic aerosol studies do not distinguish between enantiomeric compounds in the particle phase. Here we report chirally specified measurements of secondary organic aerosol (SOA) at the Amazon Tall Tower Observatory (ATTO) at different altitudes during three measurement campaigns at different seasons. Analysis of filter samples by liquid chromatography coupled to mass spectrometry (LC-MS) has shown that the chiral ratio of pinic acid (C9H14O4) varies with increasing height above the canopy. A similar trend was recently observed for the gas-phase precursor α-pinene, but more pronounced. Nevertheless, the measurements indicate that neither the oxidation of (+/−)-α-pinene nor the incorporation of the products into the particulate phase proceeds with stereo preference and that the chiral information of the precursor molecule is merely transferred to the low-volatility product. The observation of the weaker height gradient of the present enantiomers in the particle phase at the observation site can be explained by the significant differences in the atmospheric lifetimes of reactant and product. Therefore, it is suggested that the chiral ratio of pinic acid is mainly determined by large-scale emission processes of the two precursors, while meteorological, chemical, or physicochemical processes do not play a particular role. Characteristic emissions of the chiral aerosol precursors from different forest ecosystems, in some cases even with contributions from forest related fauna, could thus provide large-scale information on the different contributions to biogenic secondary aerosols via the analytics of the chiral particle-bound degradation products

Activity distribution of comet 67P/Churyumov-Gerasimenko from combined measurements of non-gravitational forces and torques

Aims. Understanding the activity is vital for deciphering the structure, formation, and evolution of comets. We investigate models of cometary activity by comparing them to the dynamics of 67P/Churyumov-Gerasimenko. Methods. We matched simple thermal models of water activity to the combined Rosetta datasets by fitting to the total outgassing rate and four components of the outgassing induced non-gravitational force and torque, with a final manual adjustment of the model parameters to additionally match the other two torque components. We parametrised the thermal model in terms of a distribution of relative activity over the surface of the comet, and attempted to link this to different terrain types. We also tested a more advanced thermal model based on a pebble structure. Results. We confirm a hemispherical dichotomy and non-linear water outgassing response to insolation. The southern hemisphere of the comet and consolidated terrain show enhanced activity relative to the northern hemisphere and dust-covered, unconsolidated terrain types, especially at perihelion. We further find that the non-gravitational torque is especially sensitive to the activity distribution, and to fit the pole-axis orientation in particular, activity must be concentrated (in excess of the already high activity in the southern hemisphere and consolidated terrain) around the south pole and on the body and neck of the comet over its head. This is the case for both the simple thermal model and the pebble-based model. Overall, our results show that water activity cannot be matched by a simple model of sublimating surface ice driven by the insolation alone, regardless of the surface distribution, and that both local spatial and temporal variations are needed to fit the data. Conclusions. Fully reconciling the Rosetta outgassing, torque, and acceleration data requires a thermal model that includes both diurnal and seasonal effects and also structure with depth (dust layers or ice within pebbles). This shows that cometary activity is complex. Nonetheless, non-gravitational dynamics provides a useful tool for distinguishing between different thermophysical models and aids our understanding