منابع مشابه
The Moon 35 years after Apollo: What’s left to learn?
With the cancellation of the Apollo program after Apollo 17 returned from the Moon in 1972, the focus of NASA switched to other areas of the Solar System. Study of the Moon did continue through analysis of the returned samples and remotely sensed data sets (both orbital and surface), as well as through Earth-based telescopic studies. In the 1990s, new orbital data were obtained from several mis...
متن کاملThe Basal Ganglia Over 500 Million Years
The lamprey belongs to the phylogenetically oldest group of vertebrates that diverged from the mammalian evolutionary line 560 million years ago. A comparison between the lamprey and mammalian basal ganglia establishes a detailed similarity regarding its input from cortex/pallium and thalamus, as well as its intrinsic organisation and projections of the output nuclei. This means that the basal ...
متن کاملGenetic Footprints of Iberian Cattle in America 500 Years after the Arrival of Columbus
BACKGROUND American Creole cattle presumably descend from animals imported from the Iberian Peninsula during the period of colonization and settlement, through different migration routes, and may have also suffered the influence of cattle directly imported from Africa. The introduction of European cattle, which began in the 18th century, and later of Zebu from India, has threatened the survival...
متن کاملSecular Variation of the Aurora for the past 500 Years
Knowledge of solar variability and its effects on the Earth is essential since the Sun affects almost every aspect of our lives. Direct observations of the Sun, usually of sunspots, with some continuity, exist only since about 1700. Understanding of long-term solar variability must then depend on proxy data, such as visual auroral observations, measurements of magnetic activity, and the radioca...
متن کاملAtmospheric carbon dioxide levels for the last 500 million years.
The last 500 million years of the strontium-isotope record are shown to correlate significantly with the concurrent record of isotopic fractionation between inorganic and organic carbon after the effects of recycled sediment are removed from the strontium signal. The correlation is shown to result from the common dependence of both signals on weathering and magmatic processes. Because the long-...
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ژورنال
عنوان ژورنال: Mechanical Engineering
سال: 2019
ISSN: 0025-6501,1943-5649
DOI: 10.1115/1.2019-jul5