43 research outputs found
Psychometric Properties and Validation of the Arabic Academic Performance Rating Scale
To validate the Arabic version of Academic Performance Rating Scale. Method. Translation and test-retest reliability were
computed. Exploratory factor analysis and Rasch analysis were conducted to report on the validity. EFA factor structures were
evaluated using a Scree plot and the standard multiple criteria included eigenvalue greater than 1. Average measures and step
measures were ordered and themean-square outfit statistic for each category was also evaluated. Results. Cronbach’s Alpha value of
0.90 was obtained. No differences across category of educational levels were seen
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
Ethylene responsive transcription factor ERF109 retards PCD and improves salt tolerance in plant
Semi-quantitative RT-PCR for tobacco VIGS lines of 13 knocked down TFs induced 2Â h post oxalic acid treatment (20Â mM) as compared to their WT and VIGS line with empty pTRV2 (V2) plants. Amplicon sizes of different genes and primers used are shown in Additional file 5: Table S3. The Nbactin gene was used as the house-keeping control. Gene codes refer to those indicated in Additional file 3: Table S2. (DOCX 684 kb
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
FabUrb©
Contribution to the exhibition “The future of tradition – the tradition of future, 100 years after the exhibition ‘masterpieces of muhammadan art’ (17 sep 10 > 09 jan 11) at the Munich Haus der Kunst, May 2010 – January 201
Preparation of Sodalite and Faujasite Clay Composite Membranes and Their Utilization in the Decontamination of Dye Effluents
The present work describes the deposition of two zeolite films, sodalite and faujasite, by the hydrothermal method to tune the mesopores of clay support, which are prepared from a widely available clay depot from the central region of Morocco (Midelt). The clay supports were prepared by a powder metallurgy method from different granulometries with activated carbon as a porosity agent, using uniaxial compression followed by a sintering process. The 160 µm ≤ Φ ≤ 250 µm support showed the highest water flux compared to the supports made from smaller granulometries with a minimum water flux of 1405 L.m−2·h−1 after a working time of 2 h and 90 min. This support was chosen for the deposition of sodalite (SOM) and faujasite (FAM) zeolite membranes. The X-ray diffraction of sodalite and faujasite showed that they were well crystallized, and the obtained spectra corresponded well with the sought phases. Such findings were confirmed by the SEM analysis, which showed that SOM was crystalized as fine particles while the FAM micrographs showed the existence of crystals with an average size ranging from 0.53 µm to 1.8 µm with a bipyramidal shape and a square or Cubo octahedral base. Nitrogen adsorption analysis showed that the pore sizes of the supports got narrowed to 2.28 nm after deposition of sodalite and faujasite. The efficiencies of SOM and FAM membranes were evaluated by filtration tests of solutions containing methyl orange (MO) using a flow loop, which were developed for dead-end filtration. The retention of methylene orange (MO) followed the order: SOM > FAM > 160 µm ≤ Φ ≤ 250 µm clay support with 55%, 48% and 35%, respectively. Size exclusion was the predominant mechanism of filtration of MO through SOM, FAM, and the support. However, the charge repulsion between the surface of the membrane and the negatively charged MO have not been ruled out. The point of zero charge (pzc) of the clay support, SOM and FAM membrane were pHpzc = 9.4, pHpzc = 10.6, and pHpzc = 11.4, respectively. Filtrations of MO were carried out between pH = 5.5 and pH = 6.5, which indicated that the surface of the membranes was positively charged while MO was negatively charged. The interaction of MO with the membranes might have happened through its vertical geometry