Search Results
You are looking at 1 - 10 of 10 items for
- Author or Editor: S. M. Ma x
- Refine by Access: All Content x
Abstract
The effect of gamma-radiations on bilirubin, in vitro, has been studied. It was found that gamma-radiation causes oxidation of bilirubin to biliverdine as one of the products. The likely implication of this effect in transformation of bilirubin to excretable products, in vivo, in case of jaundice is discussed.
The quest for precise and rapid phenotyping of germplasm is increasing the interest of breeders and physiologists in the application of remote sensing techniques in maize breeding. Twenty-four drought-tolerant maize inbred lines were crossed using a modified North Carolina II mating scheme to generate 96 single-cross hybrids. The parents and the hybrids were evaluated under full irrigation and drought stress conditions in the dry seasons of 2010 and 2011 at Ikenne, southwest Nigeria. Normalized difference vegetation index (NDVI) was recorded at 3- and 8-leaf growth stages. Hybrids differed significantly for NDVI. Both general (GCA) and specific (SCA) combining ability effects were significant for NDVI measured at 8-leaf stage under both irrigation regimes, with GCA accounting for 53% of the total variation under full irrigation. Both additive and non-additive genetic effects played significant roles in the inheritance of NDVI. The females GCA effects for grain yield was positively correlated with females GCA effects for NDVI (r = 0.72, p < 0.0001) and the male GCA effects for grain yield was also correlated with males GCA effects for NDVI (r = 0.78, p < 0.0001) at 8-leaf stage under full irrigation. These results indicate that live green biomass accumulation in maize could be identified through early screening of a large number of genotypes using NDVI for developing productive hybrids.
Abstract
Archaeological ceramic fragments from Água Limpa site, in São Paulo, Brazil, were analyzed using instrumental neutron activation analysis. Multivariate statistical methods including Pearson correlation coefficient, cluster and principal components analysis were used to interpret the concentration data. Rare earth and alkaline elements were highly correlated. Six principal components explained 74.9% of the total variance and five clusters were found. The sample chemical composition showed that all samples have the same provenance.
Abstract
In a preliminary study performed with the waste rocks from the future uranium mine to be explored in Brazil, 106 samples were taken from the eight main lithologies found in the massif and analysed by instrumental neutron activation analysis (INAA) for 20 elements. For samples from the same lithology, a high variability in the concentration of most of the elements was found (coefficient of variation larger than 20%), which might be attributed to either insufficient homogenisation of minerals or to local variation within lithology. The hypothesis that the variability within the lithology does not have an influence to the total variability was tested by analysing 5 replicates of the 5 most contrasting samples from the predominant lithology (plagioclase-microcline-gneiss), chosen after applying statistical evaluation (principal components and cluster analyses). Results indicated that homogenisation of samples was adequate due to low variation among replicates. The hypothesis tested was rejected with a confidence level higher than 99% for all the elements, corroborating the large intra-lithology variability.
Abstract
The k 0 parametric neutron activation analysis has been applied since 1995 in the Radiochemical Sector/CDTN, Belo Horizonte, Brazil. Several certified reference materials were studied with the aim of analysing biological samples. This work is related to an IAEA co-ordinated research project whose goal is to make a survey of the exposures to metals related to occupational diseases. It has been conducted by CDTN and government departments of health. The hair samples as bioindicators were donated by galvanising factory workers in Belo Horizonte. This city and surrounding area are important industrial centres and that industry is responsible for the majority of patients who look for medical assistance because of metal contamination. The Al, Co, Cu, Cr, La, Mn, Sb and V concentrations determined in the workers' samples suggest endogenous contamination.
The impact of trinexapac-ethyl (TE) on salinity subjected wheat plants was evaluated via pot based experiment. The treatments applied to wheat seedlings included (Ck) control (no NaCl nor TE spray), foliar spray of TE (1.95 ml L−1), only NaCl (50 mM) and NaCl+ TE (50 mM + 1.95 ml L−1). Foliar application of TE was done seven days after imposition of salinity. Growth parameters (root length, shoot length, fresh weight, and dry weight) and photosynthetic pigments content (chlorophyll a, b, a + b and a/b), water relation (water potential, osmotic potential, turgor potential and relative water contents) as well as catalase (CAT) activity exhibited marked reduction in comparison to control. In addition, an increment was noted in organic solutes content (proline, soluble protein and soluble sugar) and enzyme activity of superoxide dismutase (SOD), peroxidase (POD), and ascorbate peroxidase (APX) in stressed seedlings over control seedlings. The foliar applied TE mostly enhanced growth of salt stressed seedlings, accompanied by reinforcement in photosynthetic pigments, organic solutes, and enzyme activity (SOD, CAT, POD, and APX) in comparison to stressed seedlings. It is worthy to mention that, TE has potential to enhance salt tolerance of wheat seedlings. Thus, our findings suggest that seedling treated with TE is an effective strategy that can be used to enhance salt tolerance of wheat crop.
In this study, we employed electron microscopy to investigate the cytogenetic and embryologic mechanisms of parthenogenesis induced in the 1BL/1RS male sterile lines of wheat. Analysis of the root tips and acid polyacrylamide gel electrophoresis indicated that all of the male sterile lines and their maintainer lines were 1BL/1RS translocation lines, whereas the restorer lines were non-1BL/1RS translocation lines. Furthermore, the chromosomes of 1BL/1RS wheat lines with T. aestivum cytoplasm and Aegilops cytoplasm (include Ae. kotschyi, Ae. ventricosa, Ae. variabilis) paired abnormally at different rates during meiotic metaphase I (MMI). The translocated segment size of the 1RS chromosome and the specific nuclear–alloplasm interaction impaired the pairing of homologous chromosome in the background of the specific Aegilops cytoplasm at MMI. In addition, the frequency of abnormal chromosomal pairing was directly affected by the frequency of haploid production induced by parthenogenesis. The results of this study provide significant insights into the mechanism of parthenogenesis, which is probably due to the abnormal fertilization of synergid cells in alloplasmic 1BL/1RS wheat.
In the dairy industry different types of prebiotics, such galacto-oligosaccharide, lactulose, lactosucrose, tagatose, lactitol, lactobiono- and glucono-δ-lactone are synthesized through different chemical and biochemical reactions (hydrolysis, transgalactosylation, isomerization, fructosyl-transfer, reduction, and oxidation) as well as microbial fermentation processes using raw whey or isolated lactose as feedstock. Lactose-derived prebiotics have several functional and nutritional values. The biochemical activities of lactose-based prebiotics are expressed in the presence of probiotics (lactic acid bacteria, yeasts, Bacillus spp.). Galacto-oligosaccharide and lactosucrose reduce the risk of bowel disorder (diarrhea), inflammatory bowel disease (ulcerative colitis and crohn’s disease), and colon cancer. Galacto-oligosaccharide helps colonic absorption of minerals (iron, magnesium and calcium) and prevents osteoporosis. Lactulose, galacto-oligosaccharide, and lactitol promote laxative activity. Furthermore, lactulose may decrease the risk of hepatic encephalopathy. Prebiotics have low calorific value and glycemic index. Galacto-oligosaccharide and tagatose reduce the risks of hyperglycemia (Type 2 diabetes) and low density lipid (lipoprotein) accumulation in blood stream. Moreover, prebiotics improve immunomodulation, which reduces the risk of respiratory infection and allergies. This review describes unique biochemical mechanisms of several types of lactose-derived prebiotics.
The glutenin allele gene-pool, the distribution of the individual alleles on the 6 loci coding for glutenin subunits and their combinations were determined in a sample population containing 107 cultivars bred and grown in Martonvásár, Hungary at the Agricultural Research Institute of the Hungarian Academy of Sciences. The database is based on the results of three independent analytical procedures carried out using the traditional SDS-PAGE based allele identification, the state-of-art MALDI-TOF technology and the high throughput capillary electrophoresis based on the lab-on-a-chip technique. The usefulness of integrating the information on both HMW GS and LMW GS allelic composition for future genetic and technological improvement is discussed.
The complete chloroplast (cp) genome sequence of Pearl millet (Pennisetum glaucum [L.] R. Br.), an important grain and forage crop in the family Poaceae, is reported in this study. The complete cp genome sequence of P. glaucum is 138,172 bp in length with 38.6% overall GC content and exhibits a typical quadripartite structure comprising one pair of inverted repeat (IR) regions (22,275 bp) separated by a small single-copy (SSC) region (12,409 bp) and a large single-copy (LSC) region (81,213). The P. glaucum cp genome encodes 110 unique genes, 76 of which are protein-coding genes, 4 ribosomal RNA (rRNA) genes, 30 transfer RNA (tRNA) genes and 18 duplicated genes in the IR region. Nine genes contain one or two introns. Whole genome alignments of cp genome were performed for genome-wide comparison. Locally collinear blocks (LCBs) identified among the cp genomes showed that they were well conserved with respect to gene organization and order. This newly determined cp genome sequence of P. glaucum will provide valuable information for the future breeding programs of valuable cereal crops in the family Poaceae.
