6 research outputs found
Improved Nitrogen Management in Irrigated Durum Wheat Using Stem Nitrate Analysis: II. Interpretation of Nitrate‐Nitrogen Concentrations
Improved Nitrogen Management in Irrigated Durum Wheat Using Stem Nitrate Analysis: I. Nitrate Uptake Dynamics
Temporal Changes in Soil and Biomass Nitrogen for Irrigated Wheat Grown under Free‐Air Carbon Dioxide Enrichment (FACE)
Nitrogen and Water Interactions in Subsurface Drip‐Irrigated Cauliflower I. Plant Response
INTRODUÇÃO À AGRICULTURA DE PRECISÃO: CONCEITOS E VANTAGENS INTRODUCTION THE PRECISION FARMING: CONCEPTS AND ADVANTAGES
A revisão bibliográfica apresentada é uma síntese de diversos autores, os quais proporcionam uma introdução à agricultura de precisão, através de conceitos básicos e vantagens que o sistema oferece, demonstrando que não é somente uma colhedora automotriz com um sistema de posicionamento global. A agricultura de precisão pode ser considerada como um amplo conceito, englobando tecnologias e novos conhecimentos de informática, eletrônica, geoprocessamento entre outros. Este conceito incorpora um grande número de conhecimentos científicos novos e alta tecnologia, apresentando ao produtor novos termos, conceitos, equipamentos e tecnologias.<br>The presented bibliographical revision is a synthesis of several authors, which provide an introduction to the precision farming, through basic concepts and advantages that the system offers, demonstrating that it is not only a combine harvester with a global positioning system. The precision farming can be considered as a wide concept, including technologies and new computer science knowledge, electronics, geoprocessing among others. This concept incorporates a great number of new scientific knowledge and high technology, presenting to the farmer, new concepts, equipments and technologies
Modern Human Physiology with Respect to Evolutionary Adaptations that Relate to Diet in the Past
This paper reviews evidence from human physiology as to which foods may have been typically consumed by the hominin ancestral lineage up to the advent of anatomically modern humans. Considerable evidence suggests that many common diseases can be prevented by hunter-gatherer diets. Apparently, human nutritional metabolism is not perfectly fine-tuned for recently introduced staple foods, such as cereals, dairy products, added salt, and refined fats and sugar. It is much more uncertain if human physiology can provide direct evidence of which animal and plant foods were regularly consumed during human evolution, and in what proportions. The requirements of ascorbic acid can easily be met by organ meats from large animals, as well as by plant foods. Vitamin B 12 is absent in plant foods and must be supplied from meat, fish, shellfish, or insects, but the required amounts are apparently small. Since iodized salt and dairy products were not available before the advent of agriculture, only those ancestors with highly regular access to fish or shellfish would be expected to have reached the currently recommended intake of iodine. However, there is insufficient data to suggest that humans, by way of natural selection, would have become completely dependent on marine food sources. Therefore, it is highly possible that human requirements for iodine are currently increased by some dietary factors. These theoretically include goitrogens in certain roots, vegetables, beans, and seeds. The notion that humans are strictly dependent on marine foods to meet requirements of long-chain omega-3 fatty acids still awaits solid evidence. Shifting the focus from general human characteristics to ethnic differences, persistent lactase activity in adulthood is obviously not the only characteristic to have emerged under nutritional selection pressure. Other examples are a relative resistance against diseases of affluence in northern Europeans and a relatively low prevalence of gluten intolerance in populations with a long history of wheat consumption. In conclusion, humans are well adapted for lean meat, fish, insects and highly diverse plant foods without being clearly dependent on any particular proportions of plants versus meat