Search results for "CAD"
showing 10 items of 5323 documents
Effect of cadmium exposure on zinc levels in the brine shrimp Artemia parthenogenetica
1999
Zinc and cadmium have been reported as metabolic antagonists, such that high zinc intake afford animals some protection against the potentially toxic effects of cadmium exposure. There is considerable evidence to support a role of metallothioneins (MTs) in regulating or controlling the intracellular availability of essential metals and the non-essential metal. The effect of 24-h cadmium pre-exposure (10 mg Cd/l) on zinc concentrations in the brine shrimp Artemia parthenogenetica exposed to zinc (5 mg Zn/l) was studied. The zinc content of shrimps was not altered by cadmium. The homeostatic mechanism for zinc regulation appears not to be disturbed by cadmium exposure in shrimps kept in natur…
Evaluation of Antimony, Cadmium and Lead Levels in Vegetables, Drinking and Raw Water from Different Agricultural Areas
1990
Abstract Lead and cadmium levels in edible vegetables and antimony, lead and cadmium in drinking and raw waters from three agricultural areas exposed to different levels of environmental pollution (1-high industrial pollution, 2-high urban pollution, 3-standard low industrial and urban pollution) are determined. The organic matter is destroyed by repeated attack with nitric acid. Cadmium and lead are determined by graphite furnace atomic absorption spectrometry (GFAAS) and antimony by hydride generation atomic absorption spectrometry (HGAAS). When the results obtained for three different areas are compared, differences between cadmium and lead contents in vegetables are observed. Waters are…
Quantification of cadmium-induced metallothionein in crustaceans by the silver-saturation method
1995
Metallothionein (MT) has been proposed as a specific biochemical probe for metal exposure of aquatic organisms. It is recognized that its usefulness as a monitoring tool depends on the full understanding of its function and on the possibility of measuring its concentration in tissues. Therefore the study of MT in crustaceans is interesting from two different points of view: the need to understand mechanisms associated with the toxicology of metals, and the potential use of this protein for monitoring metal-contamined environments. Several methods have been developed for quantitative measurements of MT in biological samples. Immunochemical and electrochemical procedures are reliable techniqu…
The CdCl2 effects on synthetic DNAs encaged in the nanodomains of a cationic water-in-oil microemulsion
2011
The present work is dedicated to the study of the interactions of CdCl(2) with the synthetic polynucleotides polyAT and polyGC confined in the nanoscopic aqueous compartment of the water-in-oil microemulsion CTAB/pentanol/hexane/water, with the goal to mimic in vitro the situation met by the nucleic acids in vivo. In biological structures, in fact, very long strings of nucleic acids are segregated into very small compartments having a radius exceedingly smaller than the length of the encapsulated macromolecule. For comparison, the behaviour of polyGC was also studied in aqueous solutions of matched composition. The conformational and thermal stabilities of both polynucleotides enclosed in t…
Les organisations publiques : des institutions communicantes ? Le cas des Caisses d'Allocations Familiales
2009
L’objectif de cet article est de proposer une approche comprehensive de la communication des organisations publiques a travers le cas des Caisses d’Allocations Familiales (CAF). Les travaux dont il est issu ont eu pour objet d’interroger les representations des cadres, charges de communication et directeurs des CAF autour de la notion d’institution communicante. Il s’agit notamment de preciser si celle-ci releve d’un artefact ou pourrait -et a quelles conditions- constituer un modele valide pour analyser la communication des organisations publiques.
Developing development studies in North-South partnership: How to support institutional capacity in academia?
2015
Mercury beats Minerva? : essays on the accelerating impact of market logic permeating higher education
2015
Bordón : revista de pedagogía
2012
Resumen tomado de la publicación Se realiza una revisión acerca de un posible modelo de diseño y desarrollo de cuestionarios de contexto para la evaluación de sistemas educativos. Se revisan fases generales, a la par que se identifica la posible composición de indicadores simples y complejos de dichos instrumentos. En el diseño de cuestionarios de contexto hay que considerar diversos aspectos: la selección de variables e indicadores que se deben incluir como parte del modelo y el modo en que se evalúan los indicadores complejos. Éstos últimos son resultado de una escala o de la combinación de indicadores simples representados por un solo ítem. Para evaluar indicadores complejos, como el cli…
Ambidestreza y desempeño organizativo en la industria agroalimentaria ecológica en España: El papel clave de la integración de la calidad de la caden…
2018
El propósito de esta investigación es analizar el papel de la integración de la calidad de la cadena de suministro (SCQI) en el desarrollo de la ambidestreza organizativa y la influencia de esta última en la innovación de producto y el rendimiento de negocio. Para lograr con éxito este objetivo general, seguimos una serie de objetivos específicos. Primero, estudiamos los marcos teóricos de la integración de la calidad de la cadena de suministro (SCQI) y la ambidestreza organizativa, y conceptualizamos estos fenómenos utilizando las perspectivas de rutinas organizativas y capacidades dinámicas, respectivamente. A continuación, construimos un modelo teórico de influencias que relaciona cada d…