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1.
Sci Rep ; 9(1): 15179, 2019 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-31645599

RESUMO

Understanding how temperature affects the relative phenology of predators and prey is necessary to predict climate change impacts and recruitment variation. This study examines the role of temperature in the phenology of a key forage fish, the lesser sandeel (Ammodytes marinus, Raitt) and its copepod prey. Using time-series of temperature, fish larval and copepod abundance from a Scottish coastal monitoring site, the study quantifies how thermal relationships affect the match between hatching in sandeel and egg production of its copepod prey. While sandeel hatch time was found to be related to the rate of seasonal temperature decline during the autumn and winter through effects on gonad and egg development, variation in copepod timing mostly responded to February temperature. These two temperature relationships defined the degree of trophic mismatch which in turn explained variation in local sandeel recruitment. Projected warming scenarios indicated an increasing probability of phenological decoupling and concomitant decline in sandeel recruitment. This study sheds light on the mechanisms by which future warming could increase the trophic mismatch between predator and prey, and demonstrates the need to identify the temperature-sensitive stages in predator-prey phenology for predicting future responses to climate change.

2.
Sci Rep ; 8(1): 6819, 2018 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-29717139

RESUMO

Understanding micro-seismicity is a critical question for earthquake hazard assessment. Since the devastating earthquakes of Izmit and Duzce in 1999, the seismicity along the submerged section of North Anatolian Fault within the Sea of Marmara (comprising the "Istanbul seismic gap") has been extensively studied in order to infer its mechanical behaviour (creeping vs locked). So far, the seismicity has been interpreted only in terms of being tectonic-driven, although the Main Marmara Fault (MMF) is known to strike across multiple hydrocarbon gas sources. Here, we show that a large number of the aftershocks that followed the M 5.1 earthquake of July, 25th 2011 in the western Sea of Marmara, occurred within a zone of gas overpressuring in the 1.5-5 km depth range, from where pressurized gas is expected to migrate along the MMF, up to the surface sediment layers. Hence, gas-related processes should also be considered for a complete interpretation of the micro-seismicity (~M < 3) within the Istanbul offshore domain.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 100: 138-43, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-22609447

RESUMO

This study describes the use of near infrared (NIR) spectroscopy in combination with chemometrics to characterise Combretum erythrophyllum plant material to determine differences in the chemical profiles of samples harvested from mine contaminated areas and those of natural populations. The chemometric computation of near infrared vibrational spectra was used to generate principal component analysis and partial least squares models. These models were used to determine seasonal differences in the chemical matrices of samples harvested from the mine sites with different levels of contamination. Principal component analysis scatter plots illustrated clustering of phenolic profiles of samples depending on whether they originated from contaminated or uncontaminated soils. A partial least squares model was developed to link the variations in the chemical composition and levels of contamination in all samples collected in the same season (autumn). The levels of total soluble phenolic compounds in leaf extracts of C. erythrophyllum were measured using the Folin-Ciocalteau assay. Data analysis of the samples revealed that plants harvested from mine sites, particularly in summer, produced a higher level of phenolic compounds than those of the natural population, thereby displaying a good correlation with the chemometric models.


Assuntos
Química Orgânica/métodos , Combretum/metabolismo , Química Verde/métodos , Mineração , Espectroscopia de Luz Próxima ao Infravermelho , Vibração , Biodegradação Ambiental , Biomassa , Combretum/crescimento & desenvolvimento , Análise dos Mínimos Quadrados , Fenóis , Folhas de Planta/metabolismo , Análise de Componente Principal , Estações do Ano , Solubilidade
4.
J Ethnopharmacol ; 82(2-3): 147-54, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12241989

RESUMO

Natural products are becoming more important in modern-day society as man is moving away from synthetic products, which can be detrimental to the environment and human health. Scientific research on the healing properties and bioactivity of natural compounds, especially of plant origin, has been extensive particularly in the Western world. However, a rich heritage of floral biodiversity is found in developing countries. South Africa, a country with a strong history of traditional healing, hosts a variety of around 30000 plant species. Indigenous bulbous plants of importance to South African traditional healers mainly belong to the Amaryllidaceae and Hyacinthaceae families. A number of these plants have particular uses as disinfectants and anti-inflammatory agents, although there is still a lack of scientific research regarding their unique pharmacological compounds.


Assuntos
Doenças Transmissíveis/tratamento farmacológico , Medicinas Tradicionais Africanas , Plantas Medicinais , Humanos , Liliaceae , Estruturas Vegetais , África do Sul/etnologia
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