scholarly journals High-precision x-ray FEL pulse arrival time measurements at SACLA by a THz streak camera with Xe clusters

2014 ◽  
Vol 22 (24) ◽  
pp. 30004 ◽  
Author(s):  
P. N. Juranić ◽  
A. Stepanov ◽  
R. Ischebeck ◽  
V. Schlott ◽  
C. Pradervand ◽  
...  
Keyword(s):  
High Precision ◽  
Arrival Time ◽  
Streak Camera ◽  
Pulse Arrival Time ◽  
X Ray ◽  
Pulse Arrival

scholarly journals Interrelationships between pulse arrival time and arterial blood pressure during postural transitions before and after spaceflight

2019 ◽  
Vol 127 (4) ◽  
pp. 1050-1057
Author(s):  
Katelyn N. Wood ◽  
Danielle K. Greaves ◽  
Richard L. Hughson
Keyword(s):  
Blood Pressure ◽  
Arterial Blood Pressure ◽  
Arrival Time ◽  
Standing Posture ◽  
Pulse Arrival Time ◽  
Arterial Blood ◽  
Increased Risk ◽  
Before And After ◽  
Acute Changes ◽  
Pulse Arrival

We tested the hypothesis that acute changes in arterial blood pressure (BP) when astronauts moved between supine and standing posture before and after spaceflight can be tracked by beat-to-beat changes in pulse arrival time (PAT). Nine male crewmembers (45 ± 7 yr of age; mean mission length: 165 ± 13 days) participated in a standardized supine-to-sit-to-stand test (5 min-30 s-3 min) before flight and 1 day following return to Earth with continuous monitoring of ECG and finger arterial BP. PAT was determined from the R-wave of the ECG to the foot of the BP waveform. On average, modest cardiovascular deconditioning was detected by ~10 beats/min increase in heart rate in supine and standing posture after spaceflight ( P < 0.05). When looking across the full data collection period, the r2 values between inverse of PAT (1/PAT) and systolic (SBP) and diastolic BP (DBP) varied considerably between individuals (SBP preflight 0.142 ± 0.186, postflight 0.262 ± 0.243). Individual variability was consistent during periods of transition (SBP preflight 0.284 ± 0.324, postflight 0.297 ± 0.269); however, when SBP dropped >20 mmHg, r2 was significant in 5 of 5 preflight tests and 5 of 7 postflight tests. The standard error of the estimate based on a simple linear model during both pre- and postflight testing was 9–11 mmHg for SBP and 6–7 mmHg for DBP. Overall, the results support the hypothesis that PAT tracked dynamic changes in BP. PAT as a noninvasive, nonintrusive surrogate for changes in BP could be developed as an indicator of risk for syncope on return from spaceflight or other Earth-based applications. NEW & NOTEWORTHY Astronauts returning to Earth’s gravity are at increased risk of low blood pressure on standing. Arterial pulse arrival time tracked the decrease in arterial blood pressure on moving from supine to upright posture. Nonintrusive technology providing indicators sensitive to acute changes in blood pressure could act as an early warning system to identify risk for hypotension that place astronauts, or people on Earth, at risk of impaired cognitive performance, fainting, and falls.

scholarly journals Results of Pulsar Timing Observations at 102.5 MHz

1992 ◽  
Vol 128 ◽  
pp. 49-51
Author(s):  
T. V. Shabanova
Keyword(s):  
Arrival Time ◽  
Pulse Arrival Time ◽  
Pulsar Timing ◽  
Period Derivative ◽  
Significant Change ◽  
Pulse Arrival

AbstractA program of pulse arrival time observations made at Pushchino during 1978-1986 is described. The period, period derivative and position derived from the full timing solutions were obtained for 16 pulsars. Comparison of our results with others obtained during 1970-1980 by different groups has shown that the parameters for a number of pulsars have suffered a significant change.

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