Precise tracking of lung tumor motion during treatment delivery still represents a challenge in radiation therapy. Prototypes of MRI-linac hybrid systems are being created which have the potential of ionization-free real-time imaging of the tumor. This study evaluates the performance of lung tumor tracking algorithms in cine-MRI sagittal images from five healthy volunteers. Visible vascular str...

In this paper, a finite element (FE) modeling is used to model effects of the arterial stiffness on the different signal patterns of the pulse transit time (PTT). Several different breathing patterns of the three subjects are measured with PTT signal and corresponding finite element model of the straight elastic artery is applied. The computational fluid-structure model provides arterial elasti...

Abstract Introduction Differentiation between obstructive and central apneas hypopneas requires quantitative measurement of respiratory effort (RE) using esophageal pressure (PES), which is rarely implemented. This study investigated whether the sleep mandibular movements (MM) signal recorded with a tri-axial chin sensor (Sunrise, Namur, Belgium) reliable surrogate PES in patients suspected apn...

Obstructive sleep apnea (OSA) affecting human's health is a kind of major breathing-related sleep disorders and sometimes leads to nocturnal death. Respiratory rate (RR) of a sleep breathing sound signal is an important human vital sign for OSA monitoring during whole-night sleeping. A novel sleep respiratory rate detection with high computational speed based on characteristic moment waveform (...

One of the interesting problems concerning experimental results is what happens when an experiment gives a null result, when the phenomenon expected is not observed. Is it because the experimental apparatus and the associated analysis procedures cannot detect or measure the phenomenon in question or is it because the phenomenon is not present? This is a real problem in the practice of physics. ...

The use of a UWB system for sensing breathing activity of astronauts must account for many critical issues specific to the space environment. The aim of this paper is twofold. The first concerns the definition of design constraints about the pulse amplitude and waveform to transmit, as well as the immunity requirements of the receiver. The second issue concerns the assessment of the procedures ...

in this survey, asbestos fiber levels within the breathing zone of employers and in the environment of an asbestos-cement factory were monitored on membrane filter and counted by phase contrast optical microscope considering length/diameter>3:i (asbestos international associational method). the plant was fairly old and utilized both white (chrysotile) and blue (chrocidolite) asbestos. in each w...

Sleep apnoea is the most common form of different types of sleep-related breathing disorders. It is characterized by repetitive stoppage of respiratory flow during sleep. This paper discusses an approach towards identifying the presence of sleep apnoea based on the acoustic signal of respiration. Different techniques for apnoea detection are discussed in this paper. The characterization of brea...

The vital sign monitoring through Impulse Radio Ultra-Wide Band (IR-UWB) radar provides continuous assessment of a patient's respiration and heart rates in a non-invasive manner. In this paper, IR UWB radar is used for monitoring respiration and the human heart rate. The breathing and heart rate frequencies are extracted from the signal reflected from the human body. A Kalman filter is applied ...

aim and background: enuresis is known as one of the most common disorders in childhood. snoring at night and obstructive sleep apnea have been considered as probable causes, at least in some cases. thus, the importance of a breathing exercise to reduce bedwetting in children with nocturnal snoring should be noted. method and materials: this study is an experimental survey with control group. th...