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481.
Human metabolic phenotype diversity and its association with diet and blood pressure 总被引:1,自引:0,他引:1
Holmes E Loo RL Stamler J Bictash M Yap IK Chan Q Ebbels T De Iorio M Brown IJ Veselkov KA Daviglus ML Kesteloot H Ueshima H Zhao L Nicholson JK Elliott P 《Nature》2008,453(7193):396-400
Metabolic phenotypes are the products of interactions among a variety of factors-dietary, other lifestyle/environmental, gut microbial and genetic. We use a large-scale exploratory analytical approach to investigate metabolic phenotype variation across and within four human populations, based on 1H NMR spectroscopy. Metabolites discriminating across populations are then linked to data for individuals on blood pressure, a major risk factor for coronary heart disease and stroke (leading causes of mortality worldwide). We analyse spectra from two 24-hour urine specimens for each of 4,630 participants from the INTERMAP epidemiological study, involving 17 population samples aged 40-59 in China, Japan, UK and USA. We show that urinary metabolite excretion patterns for East Asian and western population samples, with contrasting diets, diet-related major risk factors, and coronary heart disease/stroke rates, are significantly differentiated (P < 10(-16)), as are Chinese/Japanese metabolic phenotypes, and subgroups with differences in dietary vegetable/animal protein and blood pressure. Among discriminatory metabolites, we quantify four and show association (P < 0.05 to P < 0.0001) of mean 24-hour urinary formate excretion with blood pressure in multiple regression analyses for individuals. Mean 24-hour urinary excretion of alanine (direct) and hippurate (inverse), reflecting diet and gut microbial activities, are also associated with blood pressure of individuals. Metabolic phenotyping applied to high-quality epidemiological data offers the potential to develop an area of aetiopathogenetic knowledge involving discovery of novel biomarkers related to cardiovascular disease risk. 相似文献
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Dislocation multi-junctions and strain hardening 总被引:2,自引:0,他引:2
Bulatov VV Hsiung LL Tang M Arsenlis A Bartelt MC Cai W Florando JN Hiratani M Rhee M Hommes G Pierce TG de la Rubia TD 《Nature》2006,440(7088):1174-1178
At the microscopic scale, the strength of a crystal derives from the motion, multiplication and interaction of distinctive line defects called dislocations. First proposed theoretically in 1934 (refs 1-3) to explain low magnitudes of crystal strength observed experimentally, the existence of dislocations was confirmed two decades later. Much of the research in dislocation physics has since focused on dislocation interactions and their role in strain hardening, a common phenomenon in which continued deformation increases a crystal's strength. The existing theory relates strain hardening to pair-wise dislocation reactions in which two intersecting dislocations form junctions that tie the dislocations together. Here we report that interactions among three dislocations result in the formation of unusual elements of dislocation network topology, termed 'multi-junctions'. We first predict the existence of multi-junctions using dislocation dynamics and atomistic simulations and then confirm their existence by transmission electron microscopy experiments in single-crystal molybdenum. In large-scale dislocation dynamics simulations, multi-junctions present very strong, nearly indestructible, obstacles to dislocation motion and furnish new sources for dislocation multiplication, thereby playing an essential role in the evolution of dislocation microstructure and strength of deforming crystals. Simulation analyses conclude that multi-junctions are responsible for the strong orientation dependence of strain hardening in body-centred cubic crystals. 相似文献
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Einwögerer T Friesinger H Händel M Neugebauer-Maresch C Simon U Teschler-Nicola M 《Nature》2006,444(7117):285
Decorations on the bodies of newborns indicate that they were probably important in their community. Several adult graves from the Stone Age (Upper Palaeolithic period) have been found but child burials seem to be rare, which has prompted discussion about whether this apparently different treatment of infants could be significant. Here we describe two recently discovered infant burials from this period at Krems-Wachtberg in Lower Austria, in which the bodies were covered with red ochre and decorated with ornaments and were therefore probably ritually buried. These findings indicate that even newborns were considered to be full members of these hunter-gatherer communities about 27,000 years ago. 相似文献
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Today, the time-to-market for plastic products ar e getting shorter, thus the lead-time for making the injection mould is decreasin g. There is potential in timesavings in the mould design stage because the design process that is repeatable for every mould design can be standardized. T he preliminary work of any final plastic injection mould design is to always pro vide an initial design of the mould assembly for product designers (customers) p rior to receiving the final product CAD data. Traditiona... 相似文献