Core of the Magnetic Obstacle

Rich recirculation patterns have been recently discovered in the electrically conducting flow subject to a local external magnetic termed "the magnetic obstacle" [Phys. Rev. Lett. 98 (2007), 144504]. This paper continues the study of magnetic obstacles and sheds new light on the core of the magnetic obstacle that develops between magnetic poles when the intensity of the external field is very large. A series of both 3D and 2D numerical simulations have been carried out, through which it is shown that the core of the magnetic obstacle is streamlined both by the upstream flow and by the induced cross stream electric currents, like a foreign insulated insertion placed inside the ordinary hydrodynamic flow. The closed streamlines of the mass flow resemble contour lines of electric potential, while closed streamlines of the electric current resemble contour lines of pressure. New recirculation patterns not reported before are found in the series of 2D simulations. These are composed of many (even number) vortices aligned along the spanwise line crossing the magnetic gap. The intensities of these vortices are shown to vanish toward to the center of the magnetic gap, confirming the general conclusion of 3D simulations that the core of the magnetic obstacle is frozen. The implications of these findings for the case of turbulent flow are discussed briefly.Comment: 14 pages, 9 figures, submitted to Journal of Turbulenc

Collider aspects of flavour physics at high Q

This review presents flavour related issues in the production and decays of heavy states at LHC, both from the experimental side and from the theoretical side. We review top quark physics and discuss flavour aspects of several extensions of the Standard Model, such as supersymmetry, little Higgs model or models with extra dimensions. This includes discovery aspects as well as measurement of several properties of these heavy states. We also present public available computational tools related to this topic.Comment: Report of Working Group 1 of the CERN Workshop ``Flavour in the era of the LHC'', Geneva, Switzerland, November 2005 -- March 200

The psychological science accelerator’s COVID-19 rapid-response dataset

In response to the COVID-19 pandemic, the Psychological Science Accelerator coordinated three large-scale psychological studies to examine the effects of loss-gain framing, cognitive reappraisals, and autonomy framing manipulations on behavioral intentions and affective measures. The data collected (April to October 2020) included specific measures for each experimental study, a general questionnaire examining health prevention behaviors and COVID-19 experience, geographical and cultural context characterization, and demographic information for each participant. Each participant started the study with the same general questions and then was randomized to complete either one longer experiment or two shorter experiments. Data were provided by 73,223 participants with varying completion rates. Participants completed the survey from 111 geopolitical regions in 44 unique languages/dialects. The anonymized dataset described here is provided in both raw and processed formats to facilitate re-use and further analyses. The dataset offers secondary analytic opportunities to explore coping, framing, and self-determination across a diverse, global sample obtained at the onset of the COVID-19 pandemic, which can be merged with other time-sampled or geographic data

Imaging of subsurface lineaments in the southwestern part of the Thrace Basin from gravity data

Linear anomalies, as an indicator of the structural features of some geological bodies, are very important for the interpretation of gravity and magnetic data. In this study, an image processing technique known as the Hough transform (HT) algorithm is described for determining invisible boundaries and extensions in gravity anomaly maps. The Hough function implements the Hough transform used to extract straight lines or circles within two-dimensional potential field images. It is defined as image and Hough space. In the Hough domain, this function transforms each nonzero point in the parameter domain to a sinusoid. In the image space, each point in the Hough space is transformed to a straight line or circle. Lineaments are depicted from these straight lines which are transformed in the image domain. An application of the Hough transform to the Bouguer anomaly map of the southwestern part of the Thrace Basin, NW Turkey, shows the effectiveness of the proposed approach. Based on geological data and gravity data, the structural features in the southwestern part of the Thrace Basin are investigated by applying the proposed approach and the Blakely and Simpson method. Lineaments identified by these approaches are generally in good accordance with previously-mapped surface faults

Composition chimique et isotopique des mégacristaux et des diamants des kimberlites du Kundelungu (Zaïre)

info:eu-repo/semantics/publishe

Symbiotic genes transferred from Sinorhizobium medicae enable Rhizobium tropici to nodulate Medicago sativa

Dryland salinity is an increasing problem in Australia, due to the rising levels of salt-laden water tables. The primary cause for the increase in salinity is thought to be the replacement of native perennial vegetation in agricultural areas with annual crops and pastures that transpire less water. Greater use in agricultural systems of deep-rooted perennials, which have greater water requirements than annuals, will help to lower the water table and prevent further salinisation of soils. Lucerne (Medicago sativa ) is the principal perennial pasture legume targetted to overcome dryland salinity in southern Australia. However, the acid sensitivity of Sinorhizobium , the microsymbiont of lucerne, limits M. sativa nodulation and establishment in many saline regions. Rhizobium tropici is a microsymbiont which is low pH tolerant; however it does not form an effective symbiosis with lucerne. This work aims to develop a strain of R. tropici which is both acid tolerant and able to effectively nodulate M. sativa , thus extending the range of soils in which lucerne can be grown. The megaplasmids of S. medicae WSM419 required for an effective symbiosis with lucerne were marked and transferred into R. tropici via Agrobacterium tumefaciens . R. tropici transconjugants containing either pSymA or pSymB from WSM419 were inoculated onto M. sativa seedlings. One of the R. tropici strains containing pSymA showed an enhanced ability to nodulate M. sativa , but the nodules were ineffective at fixing nitrogen. Current work is focussed on transferring both WSM419 megaplasmids into R. tropici , in an effort to obtain an acid-tolerant microsymbiont that can fix nitrogen with M. sativai

Biostimulation of grapevine and wheat : mode of action and possible agronomic uses

SPEIPMUBDowny mildew, caused by Plasmopara viticola, is one of the most important grape pathogen in Europe and North America. Although the control is traditionally performed with fungicides, the appearance of resistant pathogen populations and the possible adverse effects on human and environment health are spurring the search for alternative means. In the present investigation, two protein hydrolysates of soybean (soy) and casein (cas) origin were successfully tested against P. viticola. On Vitis vinifera cv. Marselan plants, the application of soy and cas reduced the infected leaf surface by 76 and 63%, as compared to the untreated control, respectively. Since both hydrolysates seemed to trigger the plant immunity, we investigated their effect on selected grapevine defense responses. On treated grapevine cell suspensions, a different free cytosolic calcium signature was recorded for each hydrolysate, whereas a similar transient phosphorylation of two MAP kinases of 45 and 49 kDa was observed. These signalling events were followed by transcriptome reprogramming, including the up-regulation of genes encoding pathogenesis-related (PR) proteins and the enzyme stilbene synthase responsible for the biosynthesis of resveratrol, the main grapevine phytoalexin. Liquid chromatography analyses confirmed the production of resveratrol and its dimer metabolites, δ- and ε-viniferins. Overall, soy effect was more pronounced than cas one. Both hydrolysates proved to be able to enhance grapevine immunity against pathogen attack