The impact of a deep convection on sulfate transport and redistribution

International audienceA three-dimensional compressible cloud model was used to simulate the processes related to dynamics, microphysics and chemistry of continental non-polluted and continental polluted clouds. The chemical components are formulated in terms of continuity equations for different chemical species in the aqueous phase within the cloud. Their evolution in this model came from not only by the processes of advection and turbulence transport, but also the chemical reactions and microphysical transfers. The model includes a method of kinetic uptake limitations. Gases with low solubility H* 3 mol dm-3 atm-1 are in Henry's law equilibrium with temperature dependence of Henry's law coefficients. Seven pollutant groups are currently included in the chemistry parameterization scheme: S(IV), S(VI), (H2O2), (O3), N(V), (NH3), (CO2). The present model contains explicit treatment of SO2 and O3, a kinetic method of gas uptake as well as an improved microphysical parameterization scheme. The primary objective of this model is to study the impact of the deep convection on the pollutant transport, redistribution and deposition. It is done through chemical reactions, oxidation, scavenging of aerosol particles and transfer via microphysical transitions among water categories. Two base run simulation parameters are used to initialize the model. The first model run is for the 6 July 1995 event, characterized by intensive convective cloud activity and a large amount of precipitation, manifested as a flashflood. The second one is related to transboundary dust transport and sulfate wet deposition. The chemical field initialization is based on the vertical distribution profiles of gases and aerosols for continental non-polluted and continental polluted background. The study has revealed the importance of considering interactions between dynamics, microphysics and cloud chemistry. Deep convection in the first analyzed case generates rapid upward and downward transport of pollutants. It stimulates the impact of scavenging processes and microphysical conversions, pollutant redistribution and wet deposition. We find good agreement between calculated and observed rainfall, pH, sulfate concentration and wet deposition, in the second simulated case. Aerosol particles partially dissolved in precipitation changed their qualitative and quantitative features, acidity and increment of all chemical components. A lot of sensitivity tests of the terms included in the chemistry parameterization scheme indicate that assumption of Henry's law equilibrium leads to a factor 2 to 3 underestimate of a soluble gas in cloud water and 3 to 5 in rainwater, respectively. Our calculations demonstrate that assumption of Henry's law leads to a factor of about 1.0 to 1.3 overestimation of the integrated sulfur mass removed by wet deposition. Analysis of the relative contribution of some parameters implies that 20% - 24% of total sulfur mass deposited belongs to both nucleation and impact scavenging. Liquid phase oxidation contributed 22% and 28% of the total sulfur mass deposited for continental non-polluted and continental polluted background, respectively. Neglecting liquid-ice phase chemical reactions leads to underestimation of the total sulfur mass deposited by about a factor of 1.0 to 1.2 for continental non-polluted and continental polluted distributions, relative to the base run

The phase sensitivity of a fully quantum three-mode nonlinear interferometer

We study a nonlinear interferometer consisting of two consecutive parametric amplifiers, where all three optical fields (pump, signal and idler) are treated quantum mechanically, allowing for pump depletion and other quantum phenomena. The interaction of all three fields in the final amplifier leads to an interference pattern from which we extract the phase uncertainty. We find that the phase uncertainty oscillates around a saturation level that decreases as the mean number $N$ of input pump photons increases. For optimal interaction strengths, we also find a phase uncertainty below the shot-noise level and obtain a Heisenberg scaling $1/N$. This is in contrast to the conventional treatment within the parametric approximation, where the Heisenberg scaling is observed as a function of the number of down-converted photons inside the interferometer.Comment: 8 pages, 7 figure

Efficient telecom to visible wavelength conversion in doubly resonant GaP microdisks

Resonant second harmonic generation between 1550 nm and 775 nm with outside efficiency $> 4.4\times10^{-4}\, \text{mW}^{-1}$ is demonstrated in a gallium phosphide microdisk cavity supporting high-$Q$ modes at visible ($Q \sim 10^4$) and infrared ($Q \sim 10^5$) wavelengths. The double resonance condition was satisfied through intracavity photothermal temperature tuning using $\sim 360\,\mu$W of 1550 nm light input to a fiber taper and resonantly coupled to the microdisk. Above this pump power efficiency was observed to decrease. The observed behavior is consistent with a simple model for thermal tuning of the double resonance condition.Comment: 6 pages, 4 figure

Perspectives on regeneration of alveolar bone defects

Bone atrophy of the alveolar process is an important parameter in patients undergoing dental implants. There are several methods for preserving the alveolar process, with the autologous bone graft as the gold standard. Other approaches include the use of allografts, xenografts and synthetic bone grafts. In recent years, the use of stem cells has increased in importance. Th e most common type of stem cells used are mesenchymal stem cells from various sources, including bone marrow, adipose tissue and dental pulp. The discovery of induced pluripotent stem cells and the continued research on embryonic stem cells open new possibilities in this field. However, further research is needed to optimise protocols for isolation, diff erentiation and transplantation of cells with or without appropriate scaff olds, and to determine the correct clinical and therapeutic implications

Intervertebral Disc and Adipokine Leptin—Loves Me, Loves Me Not

Leptin—the most famous adipose tissue-secreted hormone—in the human body is mostly observed in a negative connotation, as the hormone level increases with the accumulation of body fat. Nowadays, fatness is becoming another normal body shape. Fatness is burdened with numerous illnesses-including low back pain and degenerative disease of lumbar intervertebral disc (IVD). IVD degeneration and IVD inflammation are two indiscerptible phenomena. Irrespective of the underlying pathophysiological background (trauma, obesity, nutrient deficiency), the inflammation is crucial in triggering IVD degeneration. Leptin is usually depicted as a proinflammatory adipokine. Many studies aimed at explaining the role of leptin in IVD degeneration, though mostly in in vitro and on animal models, confirmed leptin's "bad reputation". However, several studies found that leptin might have protective role in IVD metabolism. This review examines the current literature on the metabolic role of different depots of adipose tissue, with focus on leptin, in pathogenesis of IVD degeneration

A heuristic to minimize the cardinality of a real-time task set by automated task clustering

International audienceWe propose in this paper a method to automatically map functionalities (blocks of code corresponding to high-level features) with real-time constraints to tasks (or threads). We aim at reducing the number of tasks functions are mapped to, while preserving the schedulability of the initial system. We consider independent tasks running on a single processor. Our approach has been applied with fixed-task or fixed-job priorities assigned in a Deadline Monotonic (DM) or a Earliest Deadline First (EDF) manner

The attitudes of European consumers toward innovation in bread; interest of the consumers toward selected quality attributes

16 pages, 7 tables, 4 figures.-- The definitive version is available at www3.interscience.wiley.comThe present survey is integrated in the European project entitled EU-FRESHBAKE. This three years project started in October 2006. It aims at developing innovative processes and innovative formulations for the Bake Off technology taking into consideration, energy demand of the process, nutrition parameters and overall quality of the bread. To help and to advise the project on the expectations of the European consumers toward innovation, a consumer survey has been carried out taking into consideration 1050 consumers from 5 countries (Belgium, Croatia, Spain, France and Poland). The global objectives are (i) to better understand the attitudes of the European innovations in bread and (ii) to understand the main determinants of it. Globally the key points that arose from the survey were the environmental concern and the concern regarding health; these two aspects seem to steer the attitudes of the consumer. Basically, two categories of consumers were observed; (i) frequent (daily) buyers with a focus on quality and pleasure and (ii) less frequent buyers (once a week) with a more pronounced interest in nutrition and energy (process). The first group was named the crust group and the second one the crumb group. The crumb family seems to be the one that is the most interested in the outcomes of the EU-FRESHBAKE project. This group is concerned by nutrition quality and would prefer a bread which has been done with a less energy demanding process. The “crust” group is schematically less interested in the nutrition, in the shelf life and in the energy demand of the process used to prepare the bread. The results from this survey should be handled with care due to the relative small size of the sample and to the fact that the average age of the sample was rather young.This study (report, paper, workshop…) has been carried out with financial support from the Commission of the European Communities, FP6, Thematic Area “Food quality and safety”, FOOD-2006-36302 EU-FRESH BAKE.Peer reviewe

VIRUSES OF SOME GARLIC ECOTYPES IN CROATIA

Recent, there is increasing demand for autochthonous ecotypes of garlic (Allium sativum L.) in Croatia. Many local ecotypes of garlic are developed due to specific environmental conditions and producer's selection. However, the average yield of garlic is not in the European average range, since the classical vegetative propagation from cloves usually results with virus infections that cause significant yield reduction. Viruses are considered significant garlic’s pathogens. The research was set up to determine infection rate in plant material of different garlic ecotypes grown from cloves in different regions. Plants were collected from commercial fields in Zadar County (coastal part of Croatia) and Vukovar-Srijem County (eastern Croatia) and were tested by enzyme-linked immunosorbent assay (ELISA) on the presence of three viruses: Onion yellow dwarf virus (OYDV), Leek yellow stripe virus (LYSV) and Garlic common latent virus (GCLV). As a potential source ofantigen leaf tissue was used and tests were conducted according to manufacturer’s instructions (Bioreba AG, Switzerland). In plants from Zadar County dominant was OYDV, followed by GCLV and LYSV. All tested plants originating from Vukovar-Srijem County were infected with three tested viruses. Out of 316 analyzed plants only 4 (1.3%) showed to be free from viruses included in survey. Plants infected with OYDV showed symptoms of leaf yellowing and reduced growth, while those infected with LYSV expressed yellow stripes. Symptoms were most evident at the beginning of vegetation. Due to high infection rate, deteriorated sanitary status, and increased interest in use and production of local garlic ecotypes, work on sanitary selection will be important part of revitalization program