Results 31 to 40 of about 1,108,816 (388)
Frontiers in Oncology, 2019 Hypoxia is a predominant feature in glioblastoma (GBM) and contributes greatly to its drug resistance. However, the molecular mechanisms which are responsible for the development of the resistant phenotype of GBM under hypoxic conditions remain unclear ...
Yixing Gao +21 more
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Ultra Reliable UAV Communication Using Altitude and Cooperation Diversity [PDF]
IEEE Transactions on Communications, 2017 The use of unmanned aerial vehicles (UAVs) serving as aerial base stations is expected to become predominant in the next decade. However, in order, for this technology, to unfold its full potential, it is necessary to develop a fundamental understanding ...
M. M. Azari +3 more
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Di-san junyi daxue xuebao, 2022 Objective To observe the changes of protein phosphorylation levels in the hippocampus of mice with memory impairment caused by hypobaric hypoxia exposure, and to explore the key phosphorylated proteins and associated pathways involved in memory deficits.
DONG Huaping +6 more
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British Journal of Sports Medicine, 2000 Editor,—In the early sixties I established a record for the running ascent of Kilimanjaro (19 340 feet (5985 m)) of 6 hours and 48 minutes, and my colleague (and current London marathoner) Norman Myers ran …
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Joint Altitude and Beamwidth Optimization for UAV-Enabled Multiuser Communications [PDF]
IEEE Communications Letters, 2017 We study multiuser communication systems enabled by an unmanned aerial vehicle (UAV) that is equipped with a directional antenna of adjustable beamwidth.
Haiyun He +3 more
semanticscholar +1 more source
Nature, 1883 IN NATURE, vol. xxvii. p. 176, you notice the remarkable warm and dry weather September 21 last on Ben Nevis, during an anticyclone, and, as at the foot the air was relatively cold and humid, you see in the heat and dryness on the mountain an effect of descending air currents.
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Journal of the Royal Army Medical Corps, 2005 Introduction The aims of this article are to outline the physiology of high altitude, the treatment of altitude illness and to describe opportunities for further education in mountain medicine. Human difficulty with the rarefied air at high altitudes has been recognised since ancient times.
Davis, P +4 more
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Spatiotemporal evolution of radio wave pump-induced ionospheric phenomena near the fourth electron gyroharmonic [PDF]
, 2007 On 12 November 2001, the European Incoherent Scatter (EISCAT) high-frequency (HF) radio wave transmitter facility, operating in O-mode at 5.423 MHz with 550 MW effective radiated power, produced artificial optical rings which appeared immediately at ...
Ashrafi, M. +3 more
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Postgraduate Medical Journal, 1979 Summary In studies concerned with the performance at high altitude it is often not possible to separate the effects which are due to hypoxia from those associated with the stress of ascent. Some of the basic observations concerning exercise at high altitude are reviewed and a study is described which was designed to simulate the physical
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The American Mathematical Monthly, 2023 A long-standing, unanswered question regarding Euclid's Elements concerns the absence of a theorem for the concurrence of the altitudes of a triangle, and the possible reasons for this omission. In the centuries following Euclid, a remarkable number of proofs have been put forward; this suggests a search for the most elementary and direct proof.
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