Abstract:
:Non-invasive in vivo neutron activation analysis (NAA) was used to measure the fluorine concentration in 35 people in Hamilton, Ontario, Canada. Measurement and precision data of this second generation NAA system were determined in 2013, and the results were compared with the performance of a first generation system used in a pilot study of 33 participants from the Hamilton area in 2008. Improvements in precision in line with those predicted by phantom studies were observed, but the use of fewer technicians during measurement seemed adversely to affect performance. We compared the levels of fluorine observed in people between the two studies and found them to be comparable. The average fluorine concentration in bone was found to be 3 ± 0.3 mg and 3.5 ± 0.4 mg F/g Ca for 2013 and 2008 measurements respectively. Ten people were measured in both studies; the observed average change in bone fluorine in this subgroup was consistent with that predicted by the observation of the relationship between bone fluorine and age in the wider group. In addition, we observed differences in the relationship between bone fluorine level and age between men and women, which may be attributable either to sex or gender differences. The rate of increase in fluorine content for men was found to be 0.096 ± 0.022 mg F/g Ca per year while the rate of increase for women was found to be slightly less than half that of men, 0.041 ± 0.017 mg F/g Ca per year. A discontinuity in the rate of increase in fluorine content with age was observed in women at around age 50. Bone fluorine content was significantly lower ([Formula: see text]) in women age 50 to 59 than in women age 40 to 49, which we suggest may be attributable to bone metabolism changes associated with menopause. We also observed increased fluorine levels in tea drinkers as compared to non-tea drinkers, suggesting tea may be a significant source of exposure in Canada. The rate of increase in fluorine content of the tea drinkers and the non-tea drinkers were found to be 0.127 (± 0.029) and 0.050 (± 0.009) mg F/g Ca per year respectively. Finally, we also obtained twelve bone samples from cadavers' skulls. Neutron activation analysis was used to determine the fluorine levels in these ex vivo samples. The rate of increase of fluorine content versus age for in vivo and ex vivo measurements were found to be 0.078 ± 0.014 and 0.078 ± 0.050 mg F/g Ca per year respectively. Excellent agreement was found between the fluorine levels determined in vivo and ex vivo using the two separate systems, providing confidence in the fluorine concentration data being measured in vivo.
journal_name
Physiol Measjournal_title
Physiological measurementauthors
Mostafaei F,McNeill FE,Chettle DR,Wainman BC,Pidruczny AE,Prestwich WVdoi
10.1088/0967-3334/36/3/465subject
Has Abstractpub_date
2015-03-01 00:00:00pages
465-87issue
3eissn
0967-3334issn
1361-6579journal_volume
36pub_type
杂志文章abstract::Neural gastric electrical stimulation (NGES) is a new method for invoking gastric contractions under microprocessor control. However, optimization of this technique using feedback mechanisms to minimize power consumption and maximize effectiveness has been lacking. The present pilot study proposes a prototype feedback...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/30/3/006
更新日期:2009-03-01 00:00:00
abstract::In this study, the selection of coil configuration parameters (coil radius and coil centre shift) for induced current EIT using circular coils is investigated. An alternative coil configuration is suggested, which produces approximately linear (spatially) magnetic fields in order to strengthen the currents in the cent...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/15/2a/007
更新日期:1994-05-01 00:00:00
abstract:OBJECTIVE:To investigate the effect of maternal hyperoxygenation on fetal heart rate (FHR) when applied for suspected fetal distress during the second stage of term labor. APPROACH:A single-center randomized controlled trial was conducted in a tertiary care hospital in The Netherlands. Participants were included durin...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/abc0b6
更新日期:2020-12-11 00:00:00
abstract::Spirometry is the gold standard to determine the presence of airflow obstruction, but it requires volitional participation and needs qualified supervision. The forced oscillation technique (FOT) measures respiratory input impedance (Zrs) during spontaneous breathing and it could be useful for unsupervised monitoring o...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/31/4/N01
更新日期:2010-04-01 00:00:00
abstract::Pulmonary blood volume increase during systole was measured in patients by analysing chest images obtained during ECG gated radionuclide angiography examination. The difference in the total radiation counts between systole and diastole in regions of interest, which included the lungs and the left ventricle, was measur...
journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/15/4/010
更新日期:1994-11-01 00:00:00
abstract::Muscle stiffness is known to vary as a result of a variety of disease states, yet current clinical methods for quantifying muscle stiffness have limitations including cost and availability. We investigated the capability of shear wave elastography (SWE) to measure variations in gastrocnemius shear wave speed induced v...
journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/34/6/713
更新日期:2013-06-01 00:00:00
abstract:OBJECTIVE:Transfer function analysis (TFA) of dynamic cerebral autoregulation (dCA) requires smoothing of spectral estimates using segmentation of the data (SD). Systematic studies are required to elucidate the potential influence of SD on dCA parameters. APPROACH:Healthy subjects (HS, n = 237) and acute ischaemic str...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/ab7ddf
更新日期:2020-04-17 00:00:00
abstract::Generalizability theory was used to investigate the score consistency of observed extracellular fluid/intracellular fluid (ECF/ICF) ratio measurements for both the global and leg-segmental bio-impedance spectroscopy methods. The test instrument used was a Xitron Hydra ECF/ICF Bio-Impedance Analyzer System, model 4200 ...
journal_title:Physiological measurement
pub_type: 杂志文章,随机对照试验
doi:10.1088/0967-3334/27/4/005
更新日期:2006-04-01 00:00:00
abstract::We tested the hypothesis that transmission of arterial pressure to brain tissue oxygenation is low under conditions of arterial pressure instability. Two experimental models of hemodynamic instability were used in healthy human volunteers; (1) oscillatory lower body negative pressure (OLBNP) (N = 8; 5 male, 3 female),...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/36/4/785
更新日期:2015-04-01 00:00:00
abstract:UNLABELLED:The study created an 'ex vivo' model to test different algorithms for measurements of mucosal haemoglobin saturation with visible light spectrophotometry (VLS). The model allowed comparison between algorithms, but it also allowed comparison with co-oximetry using a 'gold standard' method. This has not been d...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/37/9/1624
更新日期:2016-09-01 00:00:00
abstract:OBJECTIVE:Observational studies suggest that obesity might have a Mendelian origin, but it is not clear if gene expression patterns observed in obese subjects are secondary to genetic traits or not. APPROACH:Here we test a transcriptomic signature of obesity previously identified by our group on a large cohort of twin...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aab85a
更新日期:2018-04-26 00:00:00
abstract::The increasing use of EIT in clinical research on severely ill lung patients requires a clarification of the influence of pathologic impedance distributions on the validity of the resulting tomograms. Significant accumulation of low-conducting air (e.g. pneumothorax or emphysema) or well-conducting liquid (e.g. haemat...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/27/5/S16
更新日期:2006-05-01 00:00:00
abstract::Part I of this series showed that the five-element circuit model accurately mimics impedances measured using multi-frequency electrical impedance myography (MFEIM), focusing on changes brought on by disease. This paper addresses two requirements which must be met if the method is to qualify for clinical use. First, th...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/34/2/223
更新日期:2013-02-01 00:00:00
abstract::Measurements of blood volume pulse (BVP) and skin conductance are commonly used as indications of psychological arousal in affective computing and human-machine interfaces. To date, palmar surfaces remain the primary site for these measurements. Placement of sensors on palmar surfaces, however, is undesirable when rec...
journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/32/10/002
更新日期:2011-10-01 00:00:00
abstract::The purpose of this study was to examine the performance of dual-energy computed tomography (DECT) for the quantification of liver fat content (LFC). We prepared two phantoms: homogenized mixtures of porcine liver and fat and homogeneous mixtures of liver- and fat-equivalent solutions. Tubes containing mixtures with k...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/35/4/597
更新日期:2014-04-01 00:00:00
abstract::The goal of the present study was to develop and evaluate a new method for the prediction of unexplained syncope occurrences. Diagnosis of syncope is currently based on the reproduction of symptoms in combination with hypotension and bradycardia induced by a 45 min 60-70 degrees head-upright tilt test (HUTT). The main...
journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/28/2/007
更新日期:2007-02-01 00:00:00
abstract::The non-invasive measurement of free field snoring sounds to estimate the site of snoring is an important development in the diagnosis, treatment and management of sleep-related breathing disorders. We investigated characteristics of the probability density function by testing the sensitivity of the statistical moment...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/28/10/008
更新日期:2007-10-01 00:00:00
abstract::The effects of mechanical stimulation on hemodynamics, such as due to mechanotransduction in vascular endothelial cells, have been widely discussed recently. We previously proposed a resonance model in which the arterial system is treated as a pressure-transmitting system, and suggested that the application of externa...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/27/2/004
更新日期:2006-02-01 00:00:00
abstract::Alzheimer's disease (AD) is a degenerative disease which causes serious cognitive decline. Studies suggest that effective treatments for AD may be aided by the detection of the disease in its early stages, prior to extensive neuronal degeneration. In this paper, we propose a set of novel techniques which could help to...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/28/4/001
更新日期:2007-04-01 00:00:00
abstract::Urinary catheters (drainage tubes) are in widespread use. The most common type of long-term catheter is the Foley, which is made from natural or synthetic rubber. Foley catheters are passed into the bladder via the urethra or the suprapubic puncture channel (through the abdominal wall). A simulator for the abdominal w...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/22/3/308
更新日期:2001-08-01 00:00:00
abstract:OBJECTIVE:Currently, continuous blood pressure (BP) measurements are mostly based on multi-sensor combinations and datasets with limited BP ranges. Besides, most BP-related features derive from the photoplethysmogram (PPG) signal. The mechanism of PPG signal formation is not considered. We aimed to design a noninvasive...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/abc8dd
更新日期:2021-01-01 00:00:00
abstract::The assessment and diagnosis of lower limb peripheral arterial occlusive disease (PAOD) is important since it can lead progressively to disabling claudication, ischaemic rest pain and gangrene. Historically, the first assessment has been palpation of the peripheral pulse since it can become damped, delayed and diminis...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/26/5/018
更新日期:2005-10-01 00:00:00
abstract::Energy scavenging has increasingly become an interesting option for powering electronic devices because of the almost infinite lifetime and the non-dependence on fuels for energy generation. Moreover, the rise of wireless technologies promises new applications in medical monitoring systems, but these still face limita...
journal_title:Physiological measurement
pub_type: 杂志文章,评审
doi:10.1088/0967-3334/30/9/R01
更新日期:2009-09-01 00:00:00
abstract::In this phenomenological study we focus on dynamic measurements of volatile organic compounds (VOCs) in exhaled breath under exercise conditions. An experimental setup efficiently combining breath-by-breath analyses using proton transfer reaction mass spectrometry (PTR-MS) with data reflecting the behaviour of major h...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/31/9/008
更新日期:2010-09-01 00:00:00
abstract:OBJECTIVE:Storage of physiological waveform data for retrospective analysis presents significant challenges. Resultant data can be very large, and therefore becomes expensive to store and complicated to manage. Traditional database approaches are not appropriate for large scale storage of physiological waveforms. Our g...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/ab7cb5
更新日期:2020-04-20 00:00:00
abstract::We present the results of using electrical impedance tomographic spectroscopy (EITS) to follow the changes in lung water induced by oleic acid. Measurements were made on three goats before and after the injection of oleic acid. In addition to the EITs measurements, lung water was also measured using a double-indicator...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/17/4a/016
更新日期:1996-11-01 00:00:00
abstract::The aim of this study was to establish whether analysis of the left ventricular pressure waveform provides indicative information about cardiac load and contractility and to develop an algorithm for computer-based assessment of changes in these variables. In eight healthy standard breed anaesthetized open-chest pigs, ...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/27/12/003
更新日期:2006-12-01 00:00:00
abstract:OBJECTIVE:Atrial fibrillation (AF) causes marked risk for patients, while silent fibrillation may remain unnoticed if not suspected and screened. Development of comfortable yet accurate beat-to-beat heart rate (HR) monitoring with good AF detection sensitivity would facilitate screening and improve treatment. The purpo...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aac9a9
更新日期:2018-06-27 00:00:00
abstract::This review describes recent developments in microfabricated flow cytometers and related microfluidic devices that can detect, analyze, and sort cells or particles. The high-speed analytical capabilities of flow cytometry depend on the cooperative use of microfluidics, optics and electronics. Along with the improvemen...
journal_title:Physiological measurement
pub_type: 杂志文章,评审
doi:10.1088/0967-3334/26/3/R02
更新日期:2005-06-01 00:00:00
abstract:OBJECTIVE:The ventilators involved in non-invasive mechanical ventilation commonly provide ventilator support via a facemask. The interface of the mask with a patient promotes air leaks that cause errors in the feedback information provided by a pneumatic sensor and hence patient-ventilator asynchrony with multiple neg...
journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aab7ac
更新日期:2018-04-26 00:00:00