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991.
Annabelle Grimm Silvia Fogliatto Peter Nick Aldo Ferrero Francesco Vidotto 《Ecology and evolution》2013,3(14):4786-4798
Weedy rice (Oryza sativa L.) is one of the major issues of rice cultivation worldwide. In Italy, it infests about 70% of the total rice area. Different Weedy Rice populations can be distinguished based on variable morphological and physiological traits; however, little is known about genetic differentiation and origin of Italian weedy rice populations. The objective of this study was to genetically and morphologically characterize and compare different Italian weedy rice populations selected on the basis of different phenotypes. The main Italian rice territory was divided into 10 geographical areas in which 40 weedy rice populations were collected and grouped according to the awn traits. All the individuals of the populations were morphologically characterized according to plant and seed traits. Genetic characterization was performed using 19 SSR markers on all the collected accessions, and several rice cultivars, including some very old (late 19th century), nowadays are no longer cultivated. ANOVA showed that morphological plant and seed traits were significantly affected by the collection area and awnedness group. The importance of the awn morphology was also reflected in the Bayesian clustering where, despite a relatively low genetic diversity, the clusters displayed different awn types. An UPGMA dendrogram confirmed the clusters detected in STRUCTURE analysis and also revealed a grouping of certain old cultivars with the weedy rice, suggesting a common origin. 相似文献
992.
Nick Wilson Nhung Nghiem Cliona Ni Mhurchu Helen Eyles Michael G. Baker Tony Blakely 《PloS one》2013,8(3)
Objective
Global health challenges include non-communicable disease burdens, ensuring food security in the context of rising food prices, and environmental constraints around food production, e.g., greenhouse gas [GHG] emissions. We therefore aimed to consider optimized solutions to the mix of food items in daily diets for a developed country population: New Zealand (NZ).Methods
We conducted scenario development and linear programming to model 16 diets (some with uncertainty). Data inputs included nutrients in foods, food prices, food wastage and food-specific GHG emissions.Findings
This study identified daily dietary patterns that met key nutrient requirements for as little as a median of NZ$ 3.17 per day (US$ 2.41/d) (95% simulation interval [SI] = NZ$ 2.86 to 3.50/d). Diets that included “more familiar meals” for New Zealanders, increased the cost. The optimized diets also had low GHG emission profiles compared with the estimate for the ‘typical NZ diet’ e.g., 1.62 kg CO2e/d for one scenario (95%SI = 1.39 to 1.85 kg CO2e) compared with 10.1 kg CO2e/d, respectively. All of the optimized low-cost and low-GHG dietary patterns had likely health advantages over the current NZ dietary pattern, i.e., lower cardiovascular disease and cancer risk.Conclusions
We identified optimal foods and dietary patterns that would lower the risk of non-communicable diseases at low cost and with low greenhouse gas emission profiles. These results could help guide central and local government decisions around which foods to focus policies on. That is which foods are most suitable for: food taxes (additions and exemptions); healthy food vouchers and subsidies; and for increased use by public institutions involved in food preparation. 相似文献993.
C. Andy Schuetz Peter Alperin Swathi Guda Andrew van Herick Bertrand Cariou David Eddy Janusz Gumprecht Antonio Nicolucci Peter Schwarz Nick J. Wareham Daniel R. Witte Ulf Smith 《PloS one》2013,8(7)
Background
No clinical trials have assessed the effects or cost-effectiveness of health check strategies to detect and manage vascular disease. We used a mathematical model to estimate the cost-effectiveness of several health check strategies in six European countries.Methods
We used country-specific data from Denmark, France, Germany, Italy, Poland, and the United Kingdom to generate simulated populations of individuals aged 40–75 eligible for health checks in those countries (e.g. individuals without a previous diagnosis of diabetes, myocardial infarction, stroke, or serious chronic kidney disease). For each country, we used the Archimedes model to compare seven health check strategies consisting of assessments for diabetes, hypertension, lipids, and smoking. For patients diagnosed with vascular disease, treatment was simulated in a standard manner. We calculated the effects of each strategy on the incidence of type 2 diabetes, major adverse cardiovascular events (MACE), and microvascular complications in addition to quality of life, costs, and cost per quality-adjusted life-year (QALY).Results
Compared with current care, health checks reduced the incidence of MACE (6–17 events prevented per 1000 people screened) and diabetes related microvasular complications (5–11 events prevented per 1000 people screened), and increased QALYs (31–59 discounted QALYs) over 30 years, in all countries. The cost per QALY of offering a health check to all individuals in the study cohort ranged from €14903 (France) to cost saving (Poland). Pre-screening the population and offering health checks only to higher risk individuals lowered the cost per QALY. Pre-screening on the basis of obesity had a cost per QALY of €10200 (France) or less, and pre-screening with a non-invasive risk score was similar.Conclusions
A vascular disease health check would likely be cost effective at 30 years in Denmark, France, Germany, Italy, Poland, and the United Kingdom. 相似文献994.
995.
Quentin P. P. Croft Federico Formenti Nick P. Talbot Daniel Lunn Peter A. Robbins Keith L. Dorrington 《PloS one》2013,8(7)
The human pulmonary vasculature constricts in response to hypercapnia and hypoxia, with important consequences for homeostasis and adaptation. One function of these responses is to direct blood flow away from poorly-ventilated regions of the lung. In humans it is not known whether the stimuli of hypercapnia and hypoxia constrict the pulmonary blood vessels independently of each other or whether they act synergistically, such that the combination of hypercapnia and hypoxia is more effective than the sum of the responses to each stimulus on its own. We independently controlled the alveolar partial pressures of carbon dioxide (Paco
2) and oxygen (Pao
2) to examine their possible interaction on human pulmonary vasoconstriction. Nine volunteers each experienced sixteen possible combinations of four levels of Paco
2 (+6, +1, −4 and −9 mmHg, relative to baseline) with four levels of Pao
2 (175, 100, 75 and 50 mmHg). During each of these sixteen protocols Doppler echocardiography was used to evaluate cardiac output and systolic tricuspid pressure gradient, an index of pulmonary vasoconstriction. The degree of constriction varied linearly with both Paco
2 and the calculated haemoglobin oxygen desaturation (1-So
2). Mixed effects modelling delivered coefficients defining the interdependence of cardiac output, systolic tricuspid pressure gradient, ventilation, Paco
2 and So
2. No interaction was observed in the effects on pulmonary vasoconstriction of carbon dioxide and oxygen (p>0.64). Direct effects of the alveolar gases on systolic tricuspid pressure gradient greatly exceeded indirect effects arising from concurrent changes in cardiac output. 相似文献
996.
David H. Jewson Nick G. Granin Andre A. Zhdarnov Ludmilla A. Gorbunova Ruslan Yu. Gnatovsky 《欧洲藻类学杂志》2013,48(4):354-364
Aulacoseira baicalensis (K. Meyer) Simonsen is a freshwater planktonic diatom that undergoes large seasonal changes in cell morphology related to changes in vertical mixing. Short cells (10–20 µm) with thin walls were formed under the ice of Lake Baikal but cell lengths increased up to 150 µm by the time mixing depth reached over 100 m in June. These long cells became resting stages that were packed with reserve products and had siliceous walls up to 4 µm thick. Increase in mixing depth gave access to sufficient silica for completion of resting stages in most years but not in high biomass years, which has long-term implications for the population. Wall thickening reduced the risk of dissolution during dormancy but it also reduced cell volume. Therefore, by increasing length, cells maintained storage space for reserves. Seasonal changes in valve length showed that individual valves did not last more than 6 months, equivalent to 5 to 10 divisions. Separation valves were important in determining the number of cells per filament during spring growth but cell breakage became more important during summer dormancy. Resting stages survived in cool, intermediate depths (50–150 m) during summer stratification and were returned to the surface during autumn overturn. 相似文献
997.
Nick Lane William F. Martin John A. Raven John F. Allen 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2013,368(1622)
Life is the harnessing of chemical energy in such a way that the energy-harnessing device makes a copy of itself. No energy, no evolution. The ‘modern synthesis’ of the past century explained evolution in terms of genes, but this is only part of the story. While the mechanisms of natural selection are correct, and increasingly well understood, they do little to explain the actual trajectories taken by life on Earth. From a cosmic perspective—what is the probability of life elsewhere in the Universe, and what are its probable traits?—a gene-based view of evolution says almost nothing. Irresistible geological and environmental changes affected eukaryotes and prokaryotes in very different ways, ones that do not relate to specific genes or niches. Questions such as the early emergence of life, the morphological and genomic constraints on prokaryotes, the singular origin of eukaryotes, and the unique and perplexing traits shared by all eukaryotes but not found in any prokaryote, are instead illuminated by bioenergetics. If nothing in biology makes sense except in the light of evolution, nothing in evolution makes sense except in the light of energetics. This Special Issue of Philosophical Transactions examines the interplay between energy transduction and genome function in the major transitions of evolution, with implications ranging from planetary habitability to human health. We hope that these papers will contribute to a new evolutionary synthesis of energetics and genetics. 相似文献
998.
999.
1000.
Zavitsanos K Nunes AM Malandrinos G Hadjiliadis N 《Journal of inorganic biochemistry》2011,105(10):1329-1337
In the present study we used the plasmid relaxation assay, a very sensitive method for detection of DNA strand breaks in vitro, in order to evaluate the role of peptide fragments of histone H2B in DNA strand breakage induced by copper and nickel. We have found that in the presence of peptides modeling the histone fold domain (H2B32-62 and H2B63-93) as well as the N-terminal tail (H2B1-31) of histone H2B there is an increased DNA damage by Cu2+/H2O2 and Ni2+/H2O2 reaction mixtures. On the contrary, the C-terminal tail (H2B94-125) seems to have a protective role on the attack of ROS species to DNA. We have rendered our findings to the interactions of the peptides with DNA, as well as with the metal. 相似文献