28 research outputs found
Iodine fortification plant screening process and accumulation in tomato fruits and potato Tubers
Iodine is an essential microelement for human health, and Recommended Daily Allowance (RDA) of such element should range from 40 to 200 \ub5g day-1. Because of the low iodine contents in vegetables, cereals, and many other foods, Iodine Deficiency Disorder (IDD) is one of the most widespread nutrient deficiency diseases in the world. Therefore, investigations of iodine uptake in plants with the aim of their fortification can help reaching the important health and social objective of IDD elimination. This study was conducted to determine the effects of the absorption of iodine from two different chemical forms - potassium iodide (I-) vs. potassium iodate (IO-3) - in a wide range of wild and cultivated plant species. Pot plants were irrigated with different concentrations of I- or IO-3, namely 0.05% and 0.1% (w/v) I-, and 0.05%, 0.1%, 0.2% and 0.5% (w/v) IO-3. Inhibiting effects on plant growth were observed after adding these amounts of iodine to the irrigation water. Plants wereable to tolerate better the higher levels of iodine as IO-3 rather than I- in the root environment. Among cultivated species, barley (Hordeum vulgare L.) showed the lowest, and maize (Zea mays L.) together with tobacco (Nicotiana tabacum L.) the highest biomass reductions due to iodine toxicity. After the screening, cultivated tomato and potato resulted good targets for a fortification rate study among the species screened. When fed with 0.05% iodine salts, potato (Solanum tuberosum L.) tubers and tomato (Solanum lycopersicum L.) fruits absorbed iodine up to 272 and 527 \ub5g/100 g FW from IO-3, and 1,875 and 3,900 \ub5g/100 g FW from I-. These uptake levels were well above the RDA of 150\ub5g day-1 for adults. Moreover, the agronomic efficiency of iodine accumulation of potato tubers and tomato fruits was calculated. Both plant organs showed greater accumulation efficiency for given unit of iodine from iodide than from iodate. This accumulation efficiency decreased in both potato tubers and tomato fruits at iodine concentrations higher than 0.05% for iodide, and at respectively 0.2% and 0.1% for iodate. On the basis of the uptake curve it was finally possible to calculate, although to be validated, the doses of supply in the irrigation water of iodine as iodate (0.028% for potato, and0.014% for tomato) as well as of iodide (0.004% for potato, and 0.002% for tomato), to reach the 150 \ub5g day-1 RDA for adults in 100 g of such vegetables, to efficiently control IDD
A Revised Approach for One-Dimensional Time-Dependent Heat Conduction in a Slab
Classical Green's and Duhamel's integral formulas are enforced for the solution of one dimensional heat conduction in a slab, under general boundary conditions of the first kind. Two alternative numerical approximations are proposed, both characterized by fast convergent behavior. We first consider caloric functions with arbitrary piecewise continuous boundary conditions, and show that standard solutions based on Fourier series do not converge uniformly on the domain. Here, uniform convergence is achieved by integrations by parts. An alternative approach based on the Laplace transform is also presented, and this is shown to have an excellent convergence rate also when discontinuities are present at the boundaries. In both cases, numerical experiments illustrate the improvement of the convergence rate with respect to standard methods
A Revised Approach for One-Dimensional Time-Dependent Heat Conduction in a Slab
Classical Green\u2019s and Duhamel\u2019s integral formulas are enforced for the solution of one
dimensional heat conduction in a slab, under general boundary conditions of the first
kind. Two alternative numerical approximations are proposed, both characterized by fast convergent behavior. We first consider caloric functions with arbitrary piecewise continuous boundary conditions, and show that standard solutions based on Fourier series do not converge uniformly on the domain. Here, uniform convergence is achieved by integrations by parts. An alternative approach based on the Laplace transform is also presented, and this is shown to have an excellent convergence rate also when discontinuities are present at the boundaries. In both cases, numerical experiments illustrate the improvement of the convergence rate with respect to standard methods
Characterization of an Italian rice germplasm collection with genetic markers useful for breeding to improve eating and cooking quality
Gelatinization temperature and apparent amylose content are key parameters used to describe the eating and cooking qualities of rice. Sequence variants of SSIIa and Waxy genes are important determinants of gelatinization temperature and apparent amylose content, respectively. A collection of Italian non-glutinous japonica rice accessions was characterized for sequence polymorphisms in SSIIa and Waxy genes, in comparison with non-Italian japonica and indica genotypes. For SSIIa two markers, SNP3 and SNP4, were used. A PCR amplification of multiple specific alleles protocol was developed for the identification of G/T polymorphism in 5′ splice site of first intron and A/C polymorphism in exon 6 of the Waxy gene. Based on simple allele-specific PCR, it can be proposed as a user-friendly, cost-effective tool for marker-assisted selection of amylose content. The collection was characterized also for the (CT)n repeats in exon 1 of the Waxy gene. The results showed that while SSIIa haplotypes were rather similar between Italian and non-Italian japonica rice, the Waxy gene haplotype T/A/(CT)18 was largely predominant in Italian accessions, other haplotypes, well represented in non-Italian japonica [T/A/(CT)19] and indica [e.g. G/C/(CT)20] genotypes, were present at lower frequency. Grain starch quality traits as apparent amylose content and RVA profile were also analysed. The In1/Ex6 SNP haplotypes of Wx gene were found to explain 79 % of variation in apparent amylose content, and 36, 22 and 25 %, of variation in the RVA parameters peak viscosity, breakdown and setback, respectively. The additional use of (CT)n repeats marker further improved the association of haplotypes with RVA parameters
Femoral neuropathy caused by iliacus hematoma
Two cases of femoral neuropathy caused by iliacus hematoma occurring during anticoagulant therapy are described. The pathogenesis and the clinical picture of this particular pathology are discussed and the necessity of early surgical decompression is emphasized
QTLs and candidate genes in the ‘Nure’ x ‘Tremois’ mapping population.
In order to study in an unique genetic system cold and drought stress-related traits, together with malting quality traits, a new barley genetic map based on the 'Nure' (winter and feeding) x 'Tremois' (spring and malting) doubled-haploid population has been developed. Two low temperature tolerance QTLs were mapped on chromosome 5H. A first, distal QTL for low temperature tolerance and vernalization requirement was identified at the VrnH1/FrH1 region. A second proximal QTL of cold tolerance was coincident with two QTLs regulating the accumulation of two different COR (COld Regulated) proteins (COR14b and TMC-Ap3); the peak position of this QTL, named FrH2, is coincident with the genetic locus of the HvCBF4 barley gene, that is in turn the candidate gene underlying this QTL. The ‘Nure’ x ‘Tremois’ population is also being tested for malting quality related traits. For this purpose, two separate replicated yield trials have been set up, the first fall-sown in one location (2001/2002), and the second one for validation in different locations in Italy (2002/2003). Moreover, a multilocational irrigated vs. non-irrigated field trial in Mediterranean Europe, North Africa and West Asia is being carried out in 2004 for mapping QTLs and candidate genes for drought tolerance