1000 resultados para sensibilidad química
Resumo:
"Observando las sentencias recogidas en los medios de comunicación sobre la incapacitación laboral en pacientes con Fibromialgia, Síndrome de Fatiga Crónica o Sensibilidad Química Múltiple advertimos que dichas sentencias proceden con más frecuencia de los tribunales judiciales de Cataluña. Analizar las desigualdades territoriales en materia de incapacidad laboral y tomar las medidas correctoras adecuadas debe ser uno de los objetivos principales de las autoridades sanitarias, del Instituto Nacional de la Seguridad Social, así como de los jueces y magistrados. En este trabajo estudiamos las variables que pueden influir en estas diferencias".
Resumo:
Se ha realizado una revisión de teorías de pérdida de tolerancia inmune publicadas tratando de encontrar aquellos conceptos modernos. Las mismas se refieren a la predisposición genética, influencia de la epigenética en la modelación de un fenotipo vulnerable, las hipótesis de higiene y de microbiota, síndrome de sensibilidad química múltiple, stress crónico, cortisol, el eje hipófisis, hipotálamo y páncreas, óxido nítrico, ataque a la membrana celular, e injuria por reperfusión. Aplicando los principios básicos de las teorías consultadas se demuestra la pérdida de homeostasis, general o parcial, que podría llegar a explicar tres características fundamentales de las úlceras recurrentes orales: dolor, vulnerabilidad y recurrencia.
Resumo:
Tesis (Maestría en Ciencias con Especialidad en Química Analítica) UANL
Resumo:
Resumen basado en el de la revista. Contiene 5 anexos con los cuestionarios y resultados sobre creencias y actitudes de los estudiantes ante la problemática ambiental
Resumo:
MIPs are synthetic polymers that are used as biomimetic materials simulating the mechanism verified in natural entities such as antibodies and enzymes. Although MIPs have been successfully used as an outstanding tool for enhancing the selectivity or different analytical approaches, such as separation science and electrochemical and optical sensors, several parameters must be optimized during their synthesis. Therefore, the state-of-the-art of MIP production as well as the different polymerization methods are discussed. The potential selectivity of MIPs in the extraction and separation techniques focusing mainly on environmental, clinical and pharmaceutical samples as applications for analytical purposes is presented.
Resumo:
The aim of this paper is the description of the strategies and advances in the use of MIP in the development of chemical sensors. MIP has been considered an emerging technology, which allows the synthesis of materials that can mimic some highly specific natural receptors such as antibodies and enzymes. In recent years a great number of publications have demonstrated a growth in their use as sensing phases in the construction of sensors . Thus, the MIP technology became very attractive as a promising analytical tool for the development of sensors.
Resumo:
This article provides some aspects that allow making a current reading of the situation of the Brazilian Chemistry that permit us considerate it as a strategic area. They are still presented some initial proposals related to the organization of the research as well as to win the challenges of the relationship with the other areas of the knowledge.
Resumo:
The results of a survey of institutions offering undergraduate studies, with the objective of evaluating the importance of Qualitative Analytical Chemistry for Chemistry courses in Brazil, are presented and discussed. Judging by the data, the content of the course of Qualitative Analytical Chemistry is considered by the Brazilian institutions offering undergraduate studies to be a body of knowledge essential for the formation of the chemist. This aspect is deemed valid for both baccalaureate and teaching license studies.
Resumo:
Process Analytical Chemistry (PAC) is an important and growing area in analytical chemistry, that has received little attention in academic centers devoted to the gathering of knowledge and to optimization of chemical processes. PAC is an area devoted to optimization and knowledge acquisition of chemical processes, to reducing costs and wastes and to making an important contribution to sustainable development. The main aim of this review is to present to the Brazilian community the development and state of the art of PAC, discussing concepts, analytical techniques currently employed in the industry and some applications.
Resumo:
In this work, we describe a new method for obtaining [Fe(CO)2[(eta5-C5H5)Cl] employing simple techniques and low-cost reagents. It is worth mentioning that this method is faster than others reported in the literature. It was applied in laboratory classes for undergraduate students, exploring different concepts in organometallic chemistry and discussing the steps involved in the synthetic route.
Resumo:
There has been a considerable interest in coordination complexes of molecular nitrogen (N2), partly due to a possible relationship between such complexes and the nitrogen activation process in nature. The present paper describes the synthesis and infrared spectroscopic characterization of an iron-nitrogen derivative with ethylenediamine-N,N,N',N'-tetraacetate (edta) as an experiment for an undergraduate course. The topics covered here include synthesis, reactivity and spectroscopy.
Resumo:
The function of lipids in human nutrition has been intensively debated in the last decade.This context reinforces the concern about controlling the trans fat ingestion, due to its negative implications on health. Interesterification provides an important alternative to modify the consistency of oils and fats without causing formation of trans isomers. This article reports research done towards production of zero trans fats by chemical interesterification, for different industrial purposes. Aspects related to the effect of trans fats on diet, their impact on health and modifications in Brazilian legislation are also covered.
Resumo:
Quimica Nova and the Journal of the Brazilian Chemical Society are two examples of successful initiatives taken by the Brazilian Chemical Society (SBQ - Sociedade Brasileira de Química), and may serve as models for the scientific societies of developing countries. Pillars of the SBQ, these two periodicals are undeniable demonstrations that idealism, utopia and dignity are the essential ingredients for transforming dreams into reality. Few believed that the Brazilian chemical community would one day have, as it does today, two scientific research periodicals indexed in the principal international data banks.
Resumo:
A synthesis of (+)-±-terpineol from (+)-limonene was proposed as a project for undergraduate organic laboratory course. Terpineol is a useful flavor and fragrance compound, and several aspects of this preparation are suited for experimental organic classes, including basic techniques for extraction and analyses of essential oils, different reaction types and the possibility of a high degree of student interest.
Resumo:
Homo and heterotrinuclear acetates are unique compounds having μ3-oxo bridge and many interesting properties of such compounds are derived from this structure. Some undergraduate inorganic textbooks discuss several aspects of these compounds and we present here an undergraduate experiment for the high-yield synthesis of [Fe2MO(CH3CO2)6(H 2O)3], with M = Fe3+, Co2+ and Ni2+, as well as their characterization using infrared spectroscopy and cyclic voltametry. The proposed experiment gives the opportunity to discuss several concepts of coordination chemistry that follow the characterization techniques, such as: types of acetate coordination, reversibility of electrochemical processes, quelate and trans effects and lability.