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1.
Dalton Trans ; 53(18): 7848-7856, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38625687

RESUMEN

The paper reports on the synthesis, crystal structure, thermal and magnetic properties of spin crossover (SCO) salts containing the [Fe(bpp)2]2+ cation (bpp = 2,6-bis(pyrazol-3-yl)pyridine) and different rigid polycarboxylate anions, such as anthracene-9,10-dicarboxylate (ADC), benzene-1,3,5-tricarboxylate (BTC) and biphenyl-4,4'-dicarboxylate (BPDC). Compound [Fe(bpp)2](ADC)·9H2O (1) shows a porous hydrogen-bonded structure with water molecules sitting in the channels. It contains low-spin (LS) Fe2+ cations that undergo crossover to the high-spin (HS) state upon dehydration. Anhydrous 1 remains HS on cooling at low temperatures. A similar magnetic behaviour is obtained for the partially protonated BTC salt [Fe(bpp)2](HBTC)·5H2O (2), showing a spin change concomitant with dehydration to a HS phase that undergoes gradual and partial SCO on cooling, affecting 25% of the Fe2+ cations. Instead, the BPDC salt [Fe(bpp)2](BPDC)·5H2O (3) has a ground HS state in its fully hydrated form.

2.
Gac. sanit. (Barc., Ed. impr.) ; 31(3): 204-209, mayo-jun. 2017. tab, graf
Artículo en Español | IBECS | ID: ibc-182950

RESUMEN

Objetivo: valorar los cambios en el consumo de tabaco y estudiar de forma detallada el consumo de tabaco de liar y de cigarrillos electrónicos en la población gallega desde 2007 hasta 2015. Métodos: información aportada por cinco estudios transversales, independientes, realizados entre 2007 y 2015 en mayores de 15 años (n = 8000/año). Se estimaron prevalencias de consumo, acompañadas de sus intervalos de confianza del 95%, global, en función del sexo y en grupo de edad, ámbito de residencia y nivel de estudios. Resultados: la prevalencia de consumo de tabaco fue del 25,4% en 2007 y del 21,8% en 2015. En 2007, el 1,8% de los fumadores consumían tabaco de liar, y en 2015 eran el 18,6%. El consumo del tabaco de liar entre fumadores aumentó en todos los grupos estudiados. La prevalencia de consumo de cigarrillos electrónicos fue, en 2014 y 2015, del 0,7%. En el ámbito urbano es donde se observan prevalencias más altas de consumo de cigarrillos electrónicos. Conclusión: entre 2007 y 2015, la prevalencia de consumo de tabaco ha disminuido en Galicia y ha aumentado la prevalencia de fumadores que consumen tabaco de liar. El uso de cigarrillos electrónicos es bajo y más frecuente entre los fumadores, aunque no exclusivo. El auge del tabaco de liar y la introducción de los cigarrillos electrónicos reflejan la importancia de mantener sistemas de vigilancia que puedan identificar de forma inmediata cambios de comportamiento asociados al consumo de tabaco


Objective: to assess changes in smoking prevalence and study roll-your-own (RYO) tobacco and e-cigarette use in the Galician population between 2007 and 2015. Methods: data were obtained from five independent, cross-sectional studies carried out in Galicia (Spain) between 2007-2015 in the population aged 16 and over (n = 8,000/year). Prevalence of use was estimated, with 95% confidence intervals, overall, according to sex and by age group, area of residence and level of education. Results: smoking prevalence decreased from 25.4% in 2007 to 21.8% in 2015. In 2007, 1.8% of current smokers declared that they had smoked RYO tobacco, compared to 18.6% in 2015. Among smokers, RYO tobacco consumption increased across all demographic groups. In both 2014 and 2015, ever use of e-cigarettes was 0.7%. E-cigarette use was more frequent in urban settings. Conclusion: smoking prevalence decreased in Galicia between 2007 and 2015, and there has been rapid growth in the prevalence of RYO tobacco use. Although smokers are more likely to use e-cigarettes, both former and never smokers declared their use. The boom of RYO cigarettes and the emergence of e-cigarettes highlight the importance of having continuous surveillance systems to identify smoking behavioural changes


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Contaminación por Humo de Tabaco/prevención & control , Reducción del Consumo de Tabaco/estadística & datos numéricos , Fumar Tabaco/epidemiología , Sistemas Electrónicos de Liberación de Nicotina/estadística & datos numéricos , Cese del Uso de Tabaco/estadística & datos numéricos , Prevención del Hábito de Fumar/organización & administración , Distribución por Edad y Sexo
3.
Gac Sanit ; 31(3): 204-209, 2017.
Artículo en Español | MEDLINE | ID: mdl-27477477

RESUMEN

OBJECTIVE: To assess changes in smoking prevalence and study roll-your-own (RYO) tobacco and e-cigarette use in the Galician population between 2007 and 2015. METHODS: Data were obtained from five independent, cross-sectional studies carried out in Galicia (Spain) between 2007-2015 in the population aged 16 and over (n=8,000/year). Prevalence of use was estimated, with 95% confidence intervals, overall, according to sex and by age group, area of residence and level of education. RESULTS: Smoking prevalence decreased from 25.4% in 2007 to 21.8% in 2015. In 2007, 1.8% of current smokers declared that they had smoked RYO tobacco, compared to 18.6% in 2015. Among smokers, RYO tobacco consumption increased across all demographic groups. In both 2014 and 2015, ever use of e-cigarettes was 0.7%. E-cigarette use was more frequent in urban settings. CONCLUSION: Smoking prevalence decreased in Galicia between 2007 and 2015, and there has been rapid growth in the prevalence of RYO tobacco use. Although smokers are more likely to use e-cigarettes, both former and never smokers declared their use. The boom of RYO cigarettes and the emergence of e-cigarettes highlight the importance of having continuous surveillance systems to identify smoking behavioural changes.


Asunto(s)
Fumar Cigarrillos/epidemiología , Sistemas Electrónicos de Liberación de Nicotina/estadística & datos numéricos , Productos de Tabaco/estadística & datos numéricos , Uso de Tabaco/tendencias , Adolescente , Adulto , Anciano , Estudios Transversales , Escolaridad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Cese del Hábito de Fumar , Adulto Joven
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