A Universal Method to Generate Hyperpolarisation in Beams and Samples

Sizable hyperpolarisation, i.e. an imbalance of the occupation numbers of nuclear spins in a sample deviating from thermal equilibrium, is needed in various fields of science. For example, hyperpolarised tracers are utilised in magnetic resonance imaging in medicine (MRI) and polarised beams and targets are employed in nuclear physics to study the spin dependence of nuclear forces. Here we show that the quantum interference of transitions induced by radio-wave pumping with longitudinal and radial pulses are able to produce large polarisations at small magnetic fields. This method is easier than established methods, theoretically understood and experimentally proven for beams of metastable hydrogen atoms in the keV energy range. It should also work for a variety of samples at rest. Thus, this technique opens the door for a new generation of polarised tracers, possibly low-field MRI with better spatial resolution or the production of polarised fuel to increase the efficiency of fusion reactors by manipulating the involved cross sections.Comment: 22 pages, 9 figures, splitted into two parts: main paper and method

Metabolomic Response of Calotropis procera Growing in the Desert to Changes in Water Availability

Water availability is a major limitation for agricultural productivity. Plants growing in severe arid climates such as deserts provide tools for studying plant growth and performance under extreme drought conditions. The perennial species Calotropis procera used in this study is a shrub growing in many arid areas which has an exceptional ability to adapt and be productive in severe arid conditions. We describe the results of studying the metabolomic response of wild C procera plants growing in the desert to a one time water supply. Leaves of C. procera plants were taken at three time points before and 1 hour, 6 hours and 12 hours after watering and subjected to a metabolomics and lipidomics analysis. Analysis of the data reveals that within one hour after watering C. procera has already responded on the metabolic level to the sudden water availability as evidenced by major changes such as increased levels of most amino acids, a decrease in sucrose, raffinose and maltitol, a decrease in storage lipids (triacylglycerols) and an increase in membrane lipids including photosynthetic membranes. These changes still prevail at the 6 hour time point after watering however 12 hours after watering the metabolomics data are essentially indistinguishable from the prewatering state thus demonstrating not only a rapid response to water availability but also a rapid response to loss of water. Taken together these data suggest that the ability of C. procera to survive under the very harsh drought conditions prevailing in the desert might be associated with its rapid adjustments to water availability and losses

Assessing Phenotypic and Molecular Variability in Fennel (Foeniculum vulgare) Varieties

Abstract: Fennel, Foeniculum vulgare is an annual herb belonging to the family Apiaceae is a wellknown aromatic and medicinal herb. Three fennel varieties namely Balady (Egyptian), Indian and Holland were used. The quantitative genetic studied characters were linear growth, plant height, number of primary branches, total number of branches, peduncle length and fruit yield of plant. Fifteen promising genotypes were established within each variety. The individual plant selection procedure was practiced on intracultivar populations. The analyses of variance, broad-sense heritability, genetic advance, genotypic and phenotypic correlation coefficients were estimated. In addition, the present study was therefore aimed to focus on understanding the genetic relationship among the three studied varieties of fennel which may further assist in developing and planning breeding strategies for fennel improvement programs. Polymorphism was detected using five RAPD-PCR primers on different three fennel varieties. A total of 38 fragments were delineated out of them 26 were polymorphic. The genotypes frequencies of PCR-RAPD variants were 70.00, 80.00, 66.67, 57.14 and 70.00 with average of 68.42% polymorphism which indicated the presence of high genetic diversity in three fennel varieties. RAPD technique proved to be effective in studying inter and intra specific variation in fennel breeding and a molecular marker of germplasm conservation