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6.
Glob Chang Biol ; 23(4): 1374-1389, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27426229

RESUMEN

The cumulative effects of climate warming on herbivore vital rates and population dynamics are hard to predict, given that the expected effects differ between seasons. In the Arctic, warmer summers enhance plant growth which should lead to heavier and more fertile individuals in the autumn. Conversely, warm spells in winter with rainfall (rain-on-snow) can cause 'icing', restricting access to forage, resulting in starvation, lower survival and fecundity. As body condition is a 'barometer' of energy demands relative to energy intake, we explored the causes and consequences of variation in body mass of wild female Svalbard reindeer (Rangifer tarandus platyrhynchus) from 1994 to 2015, a period of marked climate warming. Late winter (April) body mass explained 88% of the between-year variation in population growth rate, because it strongly influenced reproductive loss, and hence subsequent fecundity (92%), as well as survival (94%) and recruitment (93%). Autumn (October) body mass affected ovulation rates but did not affect fecundity. April body mass showed no long-term trend (coefficient of variation, CV = 8.8%) and was higher following warm autumn (October) weather, reflecting delays in winter onset, but most strongly, and negatively, related to 'rain-on-snow' events. October body mass (CV = 2.5%) increased over the study due to higher plant productivity in the increasingly warm summers. Density-dependent mass change suggested competition for resources in both winter and summer but was less pronounced in recent years, despite an increasing population size. While continued climate warming is expected to increase the carrying capacity of the high Arctic tundra, it is also likely to cause more frequent icing events. Our analyses suggest that these contrasting effects may cause larger seasonal fluctuations in body mass and vital rates. Overall our findings provide an important 'missing' mechanistic link in the current understanding of the population biology of a keystone species in a rapidly warming Arctic.


Asunto(s)
Herbivoria , Reno , Animales , Regiones Árticas , Índice de Masa Corporal , Femenino , Dinámica Poblacional , Estaciones del Año , Svalbard
7.
J Perioper Pract ; 27(10): 217-223, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29328845

RESUMEN

The aim of this study was to improve emergency theatre efficiency via the introduction of a theatre booking form and morning briefing meeting. Process mapping was used to engage staff and consider if the emergency theatre may benefit from the application of a structured process of communication. A theatre booking form and morning briefing meeting were implemented to promote change. Efficiency was measured by theatre utilisation and characterised into neutral time, efficient time and inefficient time. The results demonstrated a 12.9% increase in efficient time, 3.3% fall in inefficient time and 9.6% fall in neutral time post-implementation, during the high volume work period of 08:00 to 17:59 on weekdays. No improvement in efficiency was demonstrated outside these hours or on weekends during lower volume workloads. Utilisation of a theatre booking form and morning briefing meeting improved emergency theatre efficiency during high volume work periods by the application of a structured process of communication.


Asunto(s)
Eficiencia Organizacional , Quirófanos/estadística & datos numéricos , Comunicación , Urgencias Médicas/epidemiología , Humanos , Quirófanos/organización & administración , Revisión de Utilización de Recursos
18.
Sci Total Environ ; 515-516: 1-11, 2015 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-25682473

RESUMEN

Temporal concentration trends of BPA in soils were investigated following sewage sludge application to pasture (study 1: short term sludge application; study 2: long term multiple applications over 13 years). The background levels of BPA in control soils were similar, ranging between 0.67-10.57 ng g(-1) (mean: 3.02 ng g(-1)) and 0.51-6.58 ng g(-1) (mean: 3.22 ng g(-1)) for studies 1 and 2, respectively. Concentrations in both treated and control plots increased over the earlier sampling times of the study to a maximum and then decreased over later sampling times, suggesting other sources of BPA to both the treated and control soils over the study period. In study 1 there was a significant treatment effect of sludge application in the autumn (p=0.002) although no significant difference was observed between treatment and control soils in the spring. In study 2 treated soils contained considerably higher BPA concentrations than controls ranging between 12.89-167.9 ng g(-1) (mean: 63.15 ng g(-1)). This and earlier studies indicate the long-term accumulation of multiple contaminants by multiple sewage sludge applications over a prolonged period although the effects of the presence of such contaminant mixtures have not yet been elucidated. Fugacity modelling was undertaken to estimate partitioning of Bisphenol A (soil plus sewage: pore water: soil air partitioning) and potential uptake into a range of food crops. While Bisphenol A sorbs strongly to the sewage-amended soil, 4% by mass was predicted to enter soil pore water resulting in significant uptake by crops particularly leafy vegetables (3.12-75.5 ng g(-1)), but also for root crops (1.28-31.0 ng g(-1)) with much lower uptake into cereal grains (0.62-15.0 ng g(-1)). This work forms part of a larger programme of research aimed at assessing the risks associated with the long-term application of sewage sludge to agricultural soils.


Asunto(s)
Agricultura/métodos , Compuestos de Bencidrilo/análisis , Fenoles/análisis , Contaminantes del Suelo/análisis , Eliminación de Residuos Líquidos/métodos , Productos Agrícolas , Monitoreo del Ambiente , Fertilizantes , Aguas del Alcantarillado/química , Suelo/química
20.
Int J Environ Res Public Health ; 10(9): 4086-103, 2013 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-24002726

RESUMEN

Contact with green space in the environment has been associated with mental health benefits, but the mechanism underpinning this association is not clear. This study extends an earlier exploratory study showing that more green space in deprived urban neighbourhoods in Scotland is linked to lower levels of perceived stress and improved physiological stress as measured by diurnal patterns of cortisol secretion. Salivary cortisol concentrations were measured at 3, 6 and 9 h post awakening over two consecutive weekdays, together with measures of perceived stress. Participants (n = 106) were men and women not in work aged between 35-55 years, resident in socially disadvantaged districts from the same Scottish, UK, urban context as the earlier study. Results from linear regression analyses showed a significant and negative relationship between higher green space levels and stress levels, indicating living in areas with a higher percentage of green space is associated with lower stress, confirming the earlier study findings. This study further extends the findings by showing significant gender differences in stress patterns by levels of green space, with women in lower green space areas showing higher levels of stress. A significant interaction effect between gender and percentage green space on mean cortisol concentrations showed a positive effect of higher green space in relation to cortisol measures in women, but not in men. Higher levels of neighbourhood green space were associated with healthier mean cortisol levels in women whilst also attenuating higher cortisol levels in men. We conclude that higher levels of green space in residential neighbourhoods, for this deprived urban population of middle-aged men and women not in work, are linked with lower perceived stress and a steeper (healthier) diurnal cortisol decline. However, overall patterns and levels of cortisol secretion in men and women were differentially related to neighbourhood green space and warrant further investigation.


Asunto(s)
Ambiente , Hidrocortisona/metabolismo , Características de la Residencia , Estrés Psicológico/metabolismo , Población Urbana , Adulto , Ciudades , Femenino , Humanos , Irlanda , Masculino , Persona de Mediana Edad , Saliva/metabolismo , Factores Sexuales
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