Search results for "Life"
showing 10 items of 24622 documents
Forage silica and water content control dental surface texture in guinea pigs and provide implications for dietary reconstruction.
2019
Significance Ingesta leave characteristic wear features on the tooth surface, which enable us to reconstruct the diet of extant and fossil vertebrates. However, whether dental wear is caused by internal (phytoliths) or external (mineral dust) silicate abrasives is controversially debated in paleoanthropology and biology. To assess this, we fed guinea pigs plant forages of increasing silica content (lucerne < grass < bamboo) without any external abrasives, both in fresh and dried state. Abrasiveness and enamel surface wear increased with higher forage phytolith content. Additionally, water loss altered plant material properties. Dental wear of fresh grass feeding was similar to lucerne brows…
Shape, size, and quantity of ingested external abrasives influence dental microwear texture formation in guinea pigs
2020
Food processing wears down teeth, thus affecting tooth functionality and evolutionary success. Other than intrinsic silica phytoliths, extrinsic mineral dust/grit adhering to plants causes tooth wear in mammalian herbivores. Dental microwear texture analysis (DMTA) is widely applied to infer diet from microscopic dental wear traces. The relationship between external abrasives and dental microwear texture (DMT) formation remains elusive. Feeding experiments with sheep have shown negligible effects of dust-laden grass and browse, suggesting that intrinsic properties of plants are more important. Here, we explore the effect of clay- to sand-sized mineral abrasives (quartz, volcanic ash, loess,…
Monitoring of transglutaminase crosslinking reaction by 1H NMR spectroscopy on model substrates
2015
International audience; A new method based on 1H NMR spectroscopy was developed for monitoring transglutaminase crosslinking reaction with model molecules (CBZ-Gln-Gly and N-α-acetyl-lysine). The transglutaminase reaction led to the appearance of new resonances on NMR spectrum as well as significant decrease in others. The new observed resonances, originated from newly formed ɛ-(γ-glutamyl)lysine isopeptide bonds, evidence the enzymatic reaction and allow to quantify the ɛ-(γ-glutamyl)lysine fragment. Moreover, the decrease in resonance intensity, originated from lysine, permit to determine the crosslinking degree. These results obtained by 1H NMR spectroscopy can be used as an alternative …
Plant Growth Along the Altitudinal Gradient — Role of Plant Nutritional Status, Fine Root Activity, and Soil Properties
2008
In tropical montane forests, aboveground net primary productivity (ANPP ) usually decreases with increasing altitude. Besides low photosynthesis (Kitayama and Aiba 2002) and direct impact of low temperatures on plant growth (Hoch and Korner 2003), low ANPP at high altitudes has often been attributed to nutrient limitation (Bruijnzeel et al. 1993; Bruijnzeel and Veneklaas 1998; Tanner et al. 1998). Plant growth is often correlated with nutrient availability in tropical montane forests. For example, the exceptionally high tree stature in a montane forest stand in Papua New Guinea was attributed to its nutrient rich soil parent material (Edwards and Grubb 1977). In montane forests of Jamaica (…
Prospects for the microbial production of food flavours
1996
The microbial production of natural flavours has been extensively studied during the past decade, and some processes are currently being exploited commercially. However, in the case of flavour compounds such as lactones and some aromatic compounds, the lack of basic information on their metabolism, as well as their high toxicity, are two main barriers to industrial production. The development of novel and cheap production processes, such as solid-state fermentation, may help overcome some of the current limitations of microbial flavour production, as well as widening the spectrum of biotechnologically accessible compounds.
Plant defense responses induced by arbuscular mycorrhizal fungi
2002
Plants in their environment daily face many organisms such as fungi, bacteria, mycoplasms, viruses, nematodes, etc. Many of them are potential pathogens; in fact thousands of microorganisms are known to cause plant diseases. Despite this large number of deleterious microorganisms, most of the plants are resistant to their attack since they have developed effective mechanisms to protect themselves.
Tomato and flavour
2008
Part 1: Characterization and Composition of Tomato Plant and Fruit, chapter 5; International audience
Effects of species and soil-nitrogen availability on root system architecture traits - study on a set of weed and crop species
2017
Better managing crop : weed competition in cropping systems while reducing both nitrogen and herbicide inputs is a real challenge that requires a better understanding of crop and weed root architecture in relation to soil-nitrogen availability. An original approach was used which considered the parameters of a simulation model of root architecture as traits to analyse (a) the interspecific diversity of root system architecture, and (b) its response to soil-nitrogen availability. Two greenhouse experiments were conducted using three crop and nine weed species grown at two contrasted concentrations of soil-nitrogen availability. Plant traits were measured to characterise both overall plant gr…
History of land-use intensity can modify the relationship between functional complexity of the soil fauna and soil ecosystem services - A microcosm s…
2012
Abstract Agricultural intensification generally results in the loss of soil organic matter, a decline in soil biodiversity, and the reduced ability of soils to retain nutrients. Intensified land-use can bring about legacy effects in soil ecosystem services that may last for hundreds of years after the cessation of agricultural practises. We studied, in a laboratory pot experiment, whether legacy effects due to intensive land/soil management (intensively managed wheat field) can be alleviated by restoring the disturbed soil with soil fauna typical of less managed soils (grassland soil). We also compared the effects of functional complexity of the soil fauna (microfauna, microfauna + mesofaun…
Variable impacts of enchytraeid worms and ectomycorrhizal fungi on plant growth in raw humus soil treated with wood ash
2007
Abstract An increasing amount of evidence shows the context dependent nature of various biotic interactions across terrestrial and aquatic ecosystems. We established a laboratory experiment to study whether the effects of Cognettia sphagnetorum (Enchytraeidae) and ectomycorrhizal fungi on Scots pine (Pinus sylvestris) seedling growth are influenced by wood ash application. Acidic coniferous forest soil was treated with wood ash at 5000 kg ha−1 or left as ash-free control and inoculated with soil saprotrophic microbes and nematodes. The microcosms were destructively sampled 26 and 51 weeks after initiation of the experiment. We measured enchytraeid and pine seedling biomass, abundance of nem…