2,298 research outputs found
Changes in sulfhydryl groups of honeybee glyceraldehyde phosphate dehydrogenase associated with generation of the intermediate plateau in its saturation kinetics
Honeybee and rabbit muscle GPDH were studied to obtain information at the chemical level regarding anomolous saturation kinetics of the honeybee enzyme. Results demonstrate that the enzyme's sulfhydryl groups are implicated in the process. Measured by DTNB titration, native honeybee GPDH has one less active SH than the native rabbit muscle enzyme and displays changes in overall sulfhydryl reactivity after preincubation with G-3-P or G-3-P plus NAD+. The total DTNB reactive sulfhydryls of rabbit muscle GPDH are not changed by preincubation with NAD+ or G-3-P; honeybee GPDH, under certain conductions of preincubation with these ligands, shows a decrease of two total DTNB reactive SH groups. This difference has been confirmed by an independent experiment in which the two enzymes were carboxymethylated with C-14 bromoacetic acid
Adaptation, translation, and validation of information literacy assessment instrument
The assessment of information literacy (IL) at the school level is mainly dependent on the measurement tools developed by the Western world. These tools need to be efficiently adapted and in most cases translated to allow them to be utilized in other cultures, languages, and countries. To date, there have been no standard guidelines to adapt these tools; hence, the results may be cross-culturally generalized to a certain extent. Furthermore, most data analyses produce generic outcomes without taking into account the ability of the students, including the difficulty of the test items. The present study proposes a systematic approach for context adaptation and language translation of the preexisting IL assessment tool known as TRAILS-9 to be used in different languages and context, particularly a Malaysian public secondary school. This study further administers a less common psychometric approach, the Rasch analysis, to validate the adapted instrument. This technique produces a hierarchy of item difficulty within the assessment domain that enables the ability level of the students to be differentiated based on item difficulty. The recommended scale adaptation guidelines are able to reduce the misinterpretation of scores from instruments in multiple languages as well as contribute to parallel development of IL assessment among secondary school students from different populations
The universe dynamics in the tachyon cosmology with non-minimal coupling to matter
Recently, the tachyon cosmology has been represented as dark energy model to
support the current acceleration of the universe without phantom crossing. In
this paper, we study the dynamics of the tachyon cosmology in which the field
plays the role of tachyon field and also non--minimally coupled to the matter
lagrangian. The model shows current universe acceleration and also phantom
crossing in the future. Two cosmological tests are also performed to validate
the model; the difference in the distance modulus and the model independent
Cosmological Redshift Drift (CRD) test.Comment: 14 pages, 11 figure
Application of econometric procedures to the demands for agricultural products
The objective of this study is to get for several food products the kind of demand information that is relevant when a price support administrator selects a support price. The specific problems dealt with are those of estimating the retail demand conditions for (1) pork, beef and poultry products and (2) eggs.
In connection with each problem, demand equations have been set up. In each case demand relations have been estimated by the least squares method, which treats demand equations in isolation from supply equations. Demand equations have also been estimated by simultaneous equations methods, which deal with a demand equation as part of a system of equations including a supply equation and perhaps others
Foundations of uncertainty in evaluation of nominal properties
Measurement uncertainty is a key component of metrology but, as it is defined, it does not apply to nominal properties. The possibility to define, evaluate, and express the uncertainty in the examination of nominal properties is then a critical prerequisite for a harmonized treatment of nominal properties in metrology. The assumption at the basis of this paper is that examination uncertainty can be understood in analogy with and as a generalization of measurement uncertainty. To this aim a foundational framework is introduced, grounded on a generic concept of evaluation uncertainty that applies equally to quantitative and non-quantitative evaluations. Based on this, a concept of examination uncertainty is presented and some examples of mathematical functions of examination uncertainty are proposed
Effect of linoleic acid of Nigella sativa on MDA-MB-231 human breast cancer cells.
Background: Breast cancer is one of the main life-threatening diseases which a woman may face during her life. Several lifestyle factors such as weight gain, obesity, fat intake and decreased level of physical activity are associated with breast cancer risk. In vitro and vivo studies showed that, Linoleic acid (LA) is one of the main fatty acids composition of Nigella sativa.
The objective was to investigate inhibitory and anti-cancer effects of Linoleic acid on the MDA-MB-231 human breast cancer cells.
Methods: The apoptosis and cytotoxic activity assay was used in order to find toxic effects and the results were supported by flow cytometry (Cell cycle analysis).
The results showed the cytotoxic effect of Linoleic acid on the breast cancer cell can be considered as an anti-cancer effect of LA.
Results: According to our findings, when the concentration of lionleic acid was increased, compared with the concentrations currently being reported, it showed an anti-cancer effects. The IC50 was 84.72µl/ml. There was a significant (p<0.05) effect between the treatment groups which are more than IC 50 and the control group.
Conclusion: We came to this conclusion that Linoleic acid has an inhibitory effect on human breast cancer cell lines which can be due to its two double-bandings molecular structure
Parahydrogen based NMR hyperpolarisation goes micro: an alveolus for small molecule chemosensing
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