Vanishing species: The planet in crisis

Rapid extinction of species is one of the most serious ecological problems faced by humanity today. Species are disappearing at a pace unprecedented in the history of the planet putting the very future of life at risk. The irony is that the root of the crisis is another species, Homo sapiens rather than some physical events that is poised to threaten its own survival. This article gives a brief introduction to the crisis, its consequences and possible mitigation strategies.     

Maple syrup urine disease: An uncommon cause for neonatal metabolic distress

Maple Syrup Urine Disease is an autosomal recessive disorder caused by a deficiency in the activity of the branched-chain α-ketoacid dehydrogenase complex. This rare disorder represents one of the causes of acute neonatal illness which results in devastating disturbances of neurological development. On investigation of 1750 infants with neurological impairment for inborn errors of amino acid metabolism, 4 neonates with classical maple syrup urine disease were detected. These otherwise normal neonates presented in the first week after birth with seizures, lethargy and refusal of feeds, hypoglycemia and metabolic acidosis. The plasma and urine concentrations of the branched-chain amino acids were increased and there was ketoaciduria. Two of these neonates expired before specific treatment could be instituted. Routine biochemical screening of neonates with acute illness could unearth many cases of this rare inherited metabolic disease.     

Traditional Dimensionality Versus Essential Dimensionality

This article addresses testing the hypothesis of one versus more than one dominant (essential) dimension in the possible presence of minor dimensions. The method used is Stout's statistical test of essential unidimensionality, which is based on the theory of essential unidimensionality. Differences between the traditional definition of dimensionality provided by item response theory, which counts all dimensions present, and essential dimensionality, which counts only dominant dimensions, are discussed. As Monte Carlo studies demonstrate, Stout's test of essential unidimensionality tends to indicate essential unidimensionality in the presence of one dominant dimension and one or more minor dimensions that have a relatively small influence on item scores. As the influence of the minor dimensions increases, Stout's test is more likely to reject the hypothesis of essential unidimensionality. To assist in interpreting these studies, a rough index of the deviation from essential unidimensionality is proposed.     

Dual flow immunochromatographic assay for rapid and simultaneous quantitative detection of ochratoxin A and zearalenone in corn,wheat, and feed samples

A one-step dual flow immunochromatographic assay (DICGA), based on a competitive format, was developed for simultaneous quantification of ochratoxin A (OTA) and zearalenone (ZEN) in corn, wheat, and feed samples. The limit of detection for OTA was 0.32 ng/ml with a detection range of 0.53?12.16 ng/ml, while for ZEN it was 0.58 ng/ml with a detection range of 1.06?39.72 ng/ml. The recovery rates in corn, wheat, and feed samples ranged from 77.3% to 106.3% with the coefficient of variation lower than 15%. Naturally contaminated corn, wheat, and feed samples were analyzed using both DICGA and liquid chromatography-tandem mass spectrometry (LC-MS/MS) and the correlation between the two methods was evaluated using a regression analysis. The DICGA method shows great potential for simple, rapid, sensitive, and cost-effective quantitative detection of OTA and ZEN in food safety control.     

Enumeration of lymphocyte subsets using flow cytometry: Effect of storage before and after staining in a developing country setting

Lymphocyte subset estimations by flow cytometry in population-based studies require transportation of samples from the field site to the laboratory. As samples arrive late in the day they have to wait overnight before being processed. The effect of two possible approaches, sample storage for 24 h before staining and immediate staining with analysis after 24 h and 48 h were evaluated. Two sets of experiments were performed with EDTA (ethylenediamine tetra-acetate) anticoagulated peripheral blood. In the first experiment, after collection, each sample was divided into two portions. One portion was stained at the time of blood collection and the other 24 h later after keeping it at room temperature (38–45°C). In the second experiment, blood samples were stained within 1–2 h. Each sample was analyzed immediately upon completion of staining process and subsequently after 24 h and 48 h of storage at 4°C. Results suggest that blood collected in EDTA can be processed using whole blood lysis method, after storage at room temperature (38–45°C) for 24 h with some but not significant alteration in T-cell subsets. Storage at 4°C after staining for 24 h results in a lesser and insignificant loss of cells or alteration of T-cell subsets and may be the method of choice.     

Public Education and Multicultural Policy in Canada: The Special Case of Quebec

Education is a provincial responsibility in Canada, but there is a sharing of expenditure and strong support of public education, health and other welfare programs between the provinces and the federal government. Although the federal policy of multiculturalism has been aimed at making Canada a just society, the implementation of this policy in education in English-speaking Canada has been far from satisfactory, and there is great variation among the provinces in educational programs. In Quebec, the federal policy of multiculturalism is ideologically opposed to the vision of French-Québécois nationalism. While the federal policy of intercultural education has made some attempts to integrate immigrant populations, the focus remains on linguistic programs. In facing the dramatic changes driven by internationalization and a globalized economy, Canadians must respond – so the conclusion of the present study – to the urgent need to redefine the meaning of multiculturalism with radical educational programs.     

Exploring Elementary Pre-service Teachers’ Beliefs About Science Teaching and Learning as Revealed in Their Metaphor Writing

This study examined elementary preservice teachers’ beliefs about the role/image of a science teacher and science teaching and how these beliefs change during an elementary science methods course; this examination was conducted through an analysis of their metaphor writing. Data included personal metaphors and rationale papers for supporting them collected from 106 participants at the start and end of the semester. Data were analyzed using the constant comparative method and also quantified for statistical analysis. Results indicate that most participants came to the course with traditional views and developed more constructivist views during the course. However, they tended to keep their traditional views and added new constructivist perspectives into their original belief systems. This study suggests that metaphor writing can be used as both a reflection tool for preservice teachers to clarify and refine their beliefs about science teaching and learning and a diagnostic assessment tool for teacher educators to understand their students for tailoring a methods course accordingly.     

Microwave-assisted rapid synthesis of alumina nanoparticles using tea,coffee and triphala extracts

Alumina nanoparticles （A1NP） were synthe- sized from aluminium nitrate using extracts of tea, coffee and triphala--a well known herbal plant as well as a non- toxic and eco--friendly green material. The synthesis was carried out taking 1：4 ratio of metal salt and these extracts under microwave irradiations at 540 W, which gave better yield of nanoparticles. Water was taken as solvent medium. The formations of A1NP were initially monitored by the colour changes occurring in the reaction mixture during the incubation period. As synthesized nanoparticles were characterized by scanning electron microscope （SEM）, UV-Visible （UV-Vis） spectroscopy and Fourier transform infrared spectroscopy （FTIR）. The A1NP were found to be spherical in shape in case of tea and coffee extracts with a size of 50-200 nm and to be oval shaped in case of triphala extract with an average size of 200-400 nm. The formation of A1NP with the microwave-assistance using these plant extracts has proved to be very faster than any other methods. In addition, excellent reproducibility of these nanoparticles, without the use of any additional capping agent or stabilizer will have great advantages in compari- son with microbial synthesis, avoiding all the tedious and hygienic complications.