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The effects of the 2003 European heat wave on a freshwater plankton assemblage and its fatty acid (FA) composition were investigated. Composition and FA profiles of four size categories of planktonic organisms collected in 2003 were compared to those of the colder year 2002.  相似文献   
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Introgression of spontaneous or induced mutations has been used to increase the levels and diversify the profile of antioxidants in many fruits including tomato. The high-pigment (hp) and old-gold (og) alleles exemplify this approach as attractive genetic resources suitable to inbred elite high-lycopene (HLY) tomato lines with improved color and nutritional attributes. Although several studies have been published on HLY tomatoes, a systematic analysis of the information on their agronomic performances, processing features, and functional quality is lacking, leaving room for the assumption of their poor competitiveness with conventional tomato cultivars and limiting their agricultural diffusion. Therefore, the aim of this study is to critically review the most important agronomic, horticultural, and functional traits of HLY tomatoes, as well as the advances in some emerging (pre)industrial applications. Field experiments performed in different countries showed that most available HLY lines are productive, vigorous, with excellent foliage cover and with morphologically acceptable fruit. Tomato yield of HLY genotypes ranged from ~30 to ~178 t/ha exceeding, in some trials, that of highly productive cultivars. Red-ripe fruits of most HLY lines showed commercially suitable soluble solids and titratable acidity, in addition to increased levels of lycopene (up to 440 mg/kg fw) and other bioactive phytochemicals (mainly flavonoids and vitamin C) compared to their near isogenic conventional counterparts. Innovative (pre)industrial uses of HLY tomato include the following: (1) production of HLY sauces, juices, and powders; (2) supercritical-CO2 extraction of lycopene containing oleoresins; and (3) preparation of lycopene rich micro- and nano-carriers with improved stability and specific tissue delivery. In turn, the use of these innovative high-quality ingredients in the formulation of lycopene fortified foods, cosmetic products, nutraceuticals, and pharmaceuticals has been proposed as the basis of a novel highly profitable tomato product chain.  相似文献   
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Fatty acid (FA) compositions were determined for the invader amphipod Dikerogammarus villosus collected from July to September 2002, in an overheated, high-conductivity dammed reservoir in north-eastern France. Predominant fatty acids were the polyunsaturated fatty acids (PUFA): eicosapentaenoic acid (EPA), linoleic acid (LA), arachidonic acid (ARA), linolenic acid (LNA) together with the monounsaturated fatty acid 18:1omega9 and the saturated fatty acid 16:0. FA markers indicated that available food was constituted of incompletely degraded phytodetritus and terrestrial inputs, as well as animal remains. PUFA contents depended on the diet and the capacity of animals to desaturate and elongate LNA and LA in long chain PUFA as EPA and ARA respectively. Based on their FA compositions, we showed that gammarids represent naturally-occurring freshwater sources of essential PUFA, and could play a fundamental role in pelagic-benthic coupling and energy recycling in the ecosystem. The complexity of the feeding strategies of D. villosus--detritivorous, omnivorous, carnivorous--makes this species efficient at exploiting different components of the available food and may be a key factor in its high invasive success.  相似文献   
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In Caucasian populations a single mutation, 35delG, accounts for the majority of GJB2 gene mediated hearing loss, with carrier frequencies estimated between 2-4%, possibly resulting from a founder effect rather than from a mutational hot spot. In Moroccan population, the 35delG mutation accounts for 90.8% of all GJB2 mutated alleles in deaf patients with a carrier frequency of 2.65%. The aim of this study was to evaluate whether the 35delG mutation has derived from a single origin in the Moroccan population. We enrolled 30 unrelated deaf patients homozygous for the 35delG mutation and 165 unrelated control individuals negative for this mutation, and genotyped three microsatellite markers flanking the GJB2 region: D13S141, D13S175 and D13S143. Data analysis revealed that the 35delG mutation is associated with particular alleles of these markers, with significant linkage disequilibrium for the 125 and 105 nucleotide long alleles of D13S141 and D13S175, and that a single specific haplotype accounts for 68% of the chromosomes carrying the 35delG mutation. The estimate age of 35delG mutation is 135 generations or approximately 2700 years old. Like in other Mediterranean populations, our results suggest that in the Moroccan population the 35delG mutation has derived from a single origin in a common founder process.  相似文献   
6.

Background

Households from vulnerable groups experiencing epidemiological transitions are known to be affected concomitantly by under-nutrition and obesity. Yet, it is unknown to what extent this double burden affects refugee populations dependent on food assistance. We assessed the double burden of malnutrition among Western Sahara refugees living in a protracted emergency.

Methods and Findings

We implemented a stratified nutrition survey in October–November 2010 in the four Western Sahara refugee camps in Algeria. We sampled 2,005 households, collecting anthropometric measurements (weight, height, and waist circumference) in 1,608 children (6–59 mo) and 1,781 women (15–49 y). We estimated the prevalence of global acute malnutrition (GAM), stunting, underweight, and overweight in children; and stunting, underweight, overweight, and central obesity in women. To assess the burden of malnutrition within households, households were first classified according to the presence of each type of malnutrition. Households were then classified as undernourished, overweight, or affected by the double burden if they presented members with under-nutrition, overweight, or both, respectively.The prevalence of GAM in children was 9.1%, 29.1% were stunted, 18.6% were underweight, and 2.4% were overweight; among the women, 14.8% were stunted, 53.7% were overweight or obese, and 71.4% had central obesity. Central obesity (47.2%) and overweight (38.8%) in women affected a higher proportion of households than did GAM (7.0%), stunting (19.5%), or underweight (13.3%) in children. Overall, households classified as overweight (31.5%) were most common, followed by undernourished (25.8%), and then double burden–affected (24.7%).

Conclusions

The double burden of obesity and under-nutrition is highly prevalent in households among Western Sahara refugees. The results highlight the need to focus more attention on non-communicable diseases in this population and balance obesity prevention and management with interventions to tackle under-nutrition. Please see later in the article for the Editors'' Summary  相似文献   
7.
The impact of biological invasions on local biodiversity is well established, but their impact on ecosystem functioning has only been sketchily documented. However, biological invasions may impede services provided by aquatic ecosystems, such as, for example, the decomposition of organic matter, a key process in most small streams. To address this question, we experimentally quantified the leaf litter breakdown activity of native and invasive amphipod species, which are keystone species in aquatic ecosystems. The breakdown rate of each species was used to estimate the potential leaf litter recycling in the Rhône and Meurthe Rivers in sites occupied solely by native species and sites dominated by invasive species. We found that invaders were not able to compensate for the activity of native species and that the replacement of native species led to a decrease of at least 66% in the rate of leaf litter recycling. Our approach provides empirical evidence of the functional impact of non-indigenous species on leaf litter recycling, using standard protocols and literature data.  相似文献   
8.
In a global change context, the intensity and the frequency of drastic low flow periods or drought events will most likely increase to a substantial extent over the coming decades, leading to a modification in the abiotic characteristics of wetlands. This change in environmental parameters may induce severe shifts in plant and animal communities and the functioning of ecosystems. In this study, we experimentally estimated the effect of drought and the accumulation of ammonia (NH3) on the feeding activities of three generalist macroinvertebrates (i.e. Gammarus pulex, Gammarus roeselii and Asellus aquaticus) on three types of organic matter: leaves of Berula erecta growing in submerged conditions, leaves of the same species growing in emerged conditions and dead leaves of Alnus glutinosa. We observed a modification in the biomechanical and stoichiometric characteristics of the plants as a result of the emersion of the aquatic plants. This shift produced a substantial decrease in organic matter recycling by invertebrates and in their associated physiological ability (i.e. the energy stores of the animals) to face conditions associated with environmental change. Moreover, the accumulation of NH3 amplified the negative effect of emersion. This snowball effect on invertebrates may profoundly modify the functioning of ecosystems, particularly in terms of organic matter production/degradation and carbon mineralization.  相似文献   
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