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1.
J Chromatogr A ; 1636: 461784, 2021 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-33360649

RESUMEN

Commercial gas chromatograph-mass spectrometers, one of which being Inficon's HAPSITE® ER, have demonstrated chemical detection and identification of nerve agents (G-series) and blistering agents (mustard gas) in the field; however most analyses relies on self-contained or external calibration that inherently drifts over time. We describe an analytical approach that uses target-based thermal desorption standards, called focusing agents, to accurately calculate concentrations of chemical warfare agents that are analyzed by gas chromatograph-mass spectrometry. Here, we provide relative response factors of focusing agents (2-chloroethyl ethyl sulfide, diisopropyl fluorophosphate, diethyl methylphosphonate, diethyl malonate, methyl salicylate, and dichlorvos) that are used to quantify concentrations of tabun, sarin, soman, cyclosarin and sulfur mustard loaded on thermal desorption tubes (Tenax® TA). Aging effects of focusing agents are evaluated by monitoring deviations in quantification as thermal desorption tubes age in storage at room temperature and relative humidity. The addition of focusing agents improves the quantification of tabun, sarin, soman, cyclosarin and sulfur mustard that is analyzed within the same day as well as a 14-day period. Among the six focusing agents studied here, diisopropyl fluorophosphate has the best performance for nerve agents (G-series) and blistering agents (mustard gas) compared to other focusing agents in this work and is recommended for field use for quantification. The use of focusing agent in the field leads to more accurate and reliable quantification of Tabun (GA), Sarin (GB), Soman (GD), Cyclosarin (GF) and Sulfur Mustard (HD) than the traditional internal standard. Future improvements on the detection of chemical, biological, radiological, nuclear, and explosive materials (CBRNE) can be safely demonstrated with standards calibrated for harmful agents.


Asunto(s)
Sustancias para la Guerra Química/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Gas Mostaza/análisis , Organofosfatos/análisis , Compuestos Organofosforados/análisis , Sarín/análisis , Soman/análisis , Sustancias para la Guerra Química/normas , Cromatografía de Gases y Espectrometría de Masas/instrumentación , Cromatografía de Gases y Espectrometría de Masas/normas , Estándares de Referencia
2.
J Therm Biol ; 84: 469-478, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31466788

RESUMEN

One of the main threats to freshwater turtle populations is habitat destruction, which occurs as a result of human activities such as infrastructure development, forestry, aggregate extraction, and agriculture. However, the impacts of these activities on thermoregulatory opportunities for turtles are not well understood. We examined the impacts of forestry and aggregate extraction on thermal characteristics of wood turtle (Glyptemys insculpta) habitat in the Sudbury District, Ontario, by measuring the differences in absolute temperature, thermal landscape structure, and habitat thermal quality among relatively undisturbed sites (N = 2), harvested forestry sites (N = 2), and aggregate pits (N = 2) in 2015. We also tested the potential use of the thermal landscape concept as a predictor of habitat thermal quality. Undisturbed habitats were of higher thermal quality than impacted sites in terms of temperatures experienced in situ by wild wood turtles in their natural home ranges, and never reached temperatures that would be injurious to turtles (i.e., below CTMIN or above CTMAX). The undisturbed sites were of lower quality in terms of optimal temperatures (i.e., Tset), and were generally cooler and their temperatures less variable than those in impacted habitats. The thermal landscape concept provided a useful predictor of habitat thermal quality when the influence of time of day was factored into the predictive model. Our data are important to the conservation and management of wood turtles because they provide a preliminary quantification of the thermal impacts of natural resource extraction on the habitat of an endangered species, and can guide the development of mitigation and rehabilitation plans by providing measures of, and targets for, thermal habitat quality.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Temperatura , Tortugas , Animales , Agricultura Forestal , Recursos Naturales
3.
Gynecol Oncol ; 139(1): 148-54, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26291650

RESUMEN

OBJECTIVE: To evaluate the association between body mass index (BMI), physical activity (PA) and the quality of life (QoL) of ovarian cancer survivors. METHODS: We performed a two-centre cross-sectional study of women who had been treated for ovarian cancer between January 2007 and December 2014 at the Royal Cornwall Hospital Trust and the Plymouth Hospitals NHS Trust. QoL was assessed using the EORTC QLQ-C30 and QLQ-OV28 questionnaires, and PA using the Godin Leisure Time Exercise questionnaire. RESULTS: In total, 293 ovarian cancer survivors were invited to participate, of which 209 women (71.3%) responded. Thirty-five percent of women were overweight and 18% were obese, whilst only 21% met recommendations for PA. Obesity was associated with significantly poorer global QoL, physical, cognitive and social functioning, a poorer body image and more symptomatology. Sedentary behaviour was associated with poorer QoL scores including global QoL, physical, role, social and sexual functioning. After adjustment, BMI and PA both remained independently associated with QoL scores. CONCLUSION: Obesity and inactivity are associated with poorer QoL among ovarian cancer survivors. Future interventions promoting PA and weight loss should be evaluated as possible means to improve the QoL of this population.


Asunto(s)
Actividad Motora/fisiología , Neoplasias Ováricas/fisiopatología , Neoplasias Ováricas/psicología , Pérdida de Peso/fisiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Índice de Masa Corporal , Estudios Transversales , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Ováricas/terapia , Calidad de Vida , Adulto Joven
4.
Emerg Med J ; 30(12): 988, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24232004
17.
Emerg Med J ; 29(10): 784, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23038717
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