Results 91 to 100 of about 815,050 (359)

Design and conduct of 'Xtreme Alps' : a double-blind, randomised controlled study of the effects of dietary nitrate supplementation on acclimatisation to high altitude [PDF]

, 2013
The study of healthy human volunteers ascending to high altitude provides a robust model of the complex physiological interplay that emulates human adaptation to hypoxaemia in clinical conditions.
Alexandra Cobb, Allemann, Bernadette O. Fernandez, Campbell, Daniel S. Martin, De Backer, Denny Z.H. Levett, Edward T. Gilbert-Kawai, Edwards, Erzurum, Grocott, Grocott, Grocott, Grocott, Holloway, Kay Mitchell, Larsen, Levett, Levett, Levett, Maggiorini, Martin, Martin, Martin, Martin Feelisch, Maryam Khosravi, Michael G. Mythen, Michael P.W. Grocott, Paula M. Meale, Reid, Roach, Talbot, Vanhatalo, Wasserman, Wilson, Xu, Yock   +36 more
core   +1 more source

Joint Situational Assessment‐Hierarchical Decision‐Making Framework for Maneuver Intent Decisions

Advanced Intelligent Systems, EarlyView.
This study introduces a new framework for decision‐making in unmanned combat aerial vehicles (UCAVs), integrating graph convolutional networks and hierarchical reinforcement learning (HRL). The method tackles adopts a curriculum‐based training approach guided by cross‐entropy rewards.
Ruihai Chen, Hao Li, Guanwei Yan, Haojie Peng, Qian Zhang   +4 more
wiley   +1 more source

Altitude-dependent polarization in radio pulsars [PDF]

, 2008
Because of the corotation, the polarization angle (PA) curve of a pulsar lags the intensity profile by 4r/Rlc rad in pulse phase. I present a simple and short derivation of this delay-radius relation to show that it is not caused by the aberration (understood as the normal beaming effect) but purely by contribution of corotation to the electron ...
arxiv   +1 more source

A Study on the Effect of Structural Compliance Placing in Soft Contact/Collision Properties of Multirotor Micro Aerial Vehicles

Advanced Intelligent Systems, EarlyView.
This article answers the question “Where is the best place to apply compliance in a multirotor micro aerial vehicle to make it more collision‐resilient?” by analyzing the output data of more than 1200 drone collision tests for four main configurations of micro‐quadcopters each possessing a unique softness layout of physical frame.
Amirali Abazari, Alihan Bakir, Altar Sertpoyraz, Onur Ozcan   +3 more
wiley   +1 more source

UHPLC-QTOFMS-Based Metabolomic Analysis of the Hippocampus in Hypoxia Preconditioned Mouse

Frontiers in Physiology, 2019
Background: Hypoxia appears in a number of extreme environments, including high altitudes, the deep sea, and during aviation, and occurs in cancer, cardiovascular disease, respiratory failures and neurological disorders. Though it is well recognized that
Wen-Ting Liao, Jie Liu, Jie Liu, Si-Min Zhou, Si-Min Zhou, Gang Xu, Gang Xu, Yu-Qi Gao, Yu-Qi Gao, Wen-Yuan Liu   +9 more
doaj   +1 more source

A Step Test to Evaluate the Susceptibility to Severe High-Altitude Illness in Field Conditions [PDF]

A laboratory-based hypoxic exercise test, performed on a cycle ergometer, can be used to predict susceptibility to severe high-altitude illness (SHAI) through the calculation of a clinicophysiological SHAI score. Our objective was to design a field-condition test and compare its derived SHAI score and various physiological parameters, such as ...
arxiv   +1 more source

An Aerial Robot Achieving Bimodal Flight and Independent Attitude Control through Passive Morphing

Advanced Intelligent Systems, EarlyView.
This article presents a bimodal aerial robot capable of operating in both standard quadcopter and revolving flight modes. With four rotors, it independently controls position and roll‐pitch attitude across five degrees of freedom. The design features passive revolute joints, allowing seamless mid‐air transitions between modes using centrifugal forces ...
Jihao Xu, Pakpong Chirarattananon
wiley   +1 more source

Bioactive compound combinations from Rhodiola tangutica alleviate pulmonary vascular remodeling in high-altitude pulmonary hypertension rats through the PI3K–AKT pathway

Frontiers in Pharmacology
BackgroundHypoxia-induced pulmonary vascular remodeling is central to the development of high-altitude pulmonary hypertension (HAPH). Rhodiola tangutica has traditionally been used to prevent chronic mountain sickness. Although its active fraction (ACRT)
Na Yang, Meiduo Huayu, Shanshan Su, Bin Hou, Zhanting Yang, Xingmei Nan, Zhanqiang Li, Zhanqiang Li   +7 more
doaj   +1 more source

Effect of butyrate on NO secretion from hypoxic human umbilical vein endothelial cells and its underlying mechanism

Di-san junyi daxue xuebao, 2020
Objective To investigate the molecular mechanism of hypoxia-decreased NO secretion in vascular endothelial cells, and to explore the intervention role of butyrate (Bur) in the process.
YANG Chengzhong, YANG Chengzhong, YANG Chengzhong, FENG Lan, FENG Lan, FENG Lan, CHEN Dewei, CHEN Dewei   +7 more
doaj   +1 more source

Morphy: A Compliant and Morphologically Aware Flying Robot

Advanced Intelligent Systems, EarlyView.
This study presents Morphy, a 25.2 cm‐wide, 260 g aerial robot with flexible, sensorized joints that enable it to withstand high‐speed collisions and squeeze through narrow spaces. Powered by an adaptive control scheme exploiting real‐time morphology feedback, Morphy demonstrates resilience in trajectory tracking, collision, and impact recovery and ...
Paolo De Petris, Morten Nissov, Kostas Alexis   +2 more
wiley   +1 more source