Abstract：
:Postural balance requires using joint strategies which may be changed from normal conditions by interfering with the sensory information. The goal of the present study was to quantitatively evaluate the role of the joint mechanisms during perturbed stance. Visual and cognitive interference was imposed to sixteen healthy young males under rotational toes-down or up perturbations. Power spectral analysis was employed to distinguish the joint contribution and their in- or out-phase co-works. Results showed that addition of cognitive loads reduce the stability by increasing the center of mass (CoM) power to three times greater. Besides the CoM, the knee and hip powers were also significantly enhanced by the cognitive loads (p < .004), but the ankle was not influenced by cognition involvement (p > .05). Elimination of the vision had lower effect on the time and spectral functions of the knee and hip while the ankle rotations were increased due to the lack of visual feedback (p = .001). The toes-down perturbations resulted in more prominent contribution of the knee while the toes-up evoked the hip joint to keep the balance more than the other joints. Addition of the cognitive loads hindered the reactions of the joint mechanisms and vision caused more conservative responses of the joints.
journal_name
Australas Phys Eng Sci Medjournal_title
Australasian physical & engineering sciences in medicineauthors
Ashtiani MN,Azghani MRdoi
10.1007/s13246-017-0606-7subject
Has Abstractpub_date
2018-03-01 00:00:00pages
21-30issue
1eissn
0158-9938issn
1879-5447pii
10.1007/s13246-017-0606-7journal_volume
41pub_type
杂志文章abstract：:Compression techniques are vital for efficient storage and fast transfer of medical image data. The existing compression techniques take significant amount of time for performing encoding and decoding and hence the purpose of compression is not fully satisfied. In this paper a rapid 4-D lossy compression method constr...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/s13246-015-0385-y
更新日期：2015-12-01 00:00:00
abstract：:Super-pixel feature extraction is a key problem to get an acceptable performance in color super-pixel classification. Given a color feature extraction problem, it is necessary to know which is the best approach to solve this problem. In the current work, we're interested in the challenge of nucleus and cytoplasm autom...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/s13246-019-00735-8
更新日期：2019-06-01 00:00:00
abstract：:Cone-beam computed tomography (CBCT) has become the standard imaging technique for many sites treated with Radiotherapy. The Elekta X-ray Volumetric Imaging (XVI) system allows for the acquisition of CBCTs with three different diameters; small (27 cm), medium (41 cm) and large (50 cm) (Elekta in XVI Corrective Mainten...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/s13246-019-00817-7
更新日期：2019-12-01 00:00:00
abstract：:The measurement of absorbed dose to water in a solid-phantom may require a conversion factor because it may not be radiologically equivalent to water. One phantom developed for the use of dosimetry is a solid water, RW3 white-polystyrene material by IBA. This has a lower mass-energy absorption coefficient than water d...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/s13246-011-0102-4
更新日期：2011-12-01 00:00:00
abstract：:X-ray transmission tests were performed on a Green-Lite (Infab Corporation) apron/vest combination, and compared to a number of other apron/vest combinations routinely used at Christchurch Hospital as well as a sheet of 0.5 mm lead. The materials were X-rayed using the primary beam of a Philips Optimus 50 X-ray machin...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/BF03178704
更新日期：2005-06-01 00:00:00
abstract：:Numerical simulation is performed to demonstrate that hemodynamic factors are significant determinants for the development of a vascular pathology. Experimental measurements by particle image velocimetry are carried out to validate the credibility of the computational approach. We present a study for determining compl...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/s13246-010-0050-4
更新日期：2010-12-01 00:00:00
abstract：:A electrocardiogram (ECG) central station has been developed for the Intensive Care Unit at Christchurch Hospital. The system allows the selection and display of four ECGs selected from seven bedside monitors in the Unit. It also provides for automatic display, hard copy and audio alarm of ECG from any monitor which h...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：
更新日期：1990-03-01 00:00:00
abstract：:Given the difficulty and potential time- or financial-costs associated with accurate small field dosimetry, this study aimed to establish the clinical necessity of obtaining accurate small field output factor measurements and to evaluate the effects on planned doses that could arise if accurate measurements are not us...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/s13246-016-0461-y
更新日期：2016-09-01 00:00:00
abstract：:The aim of this study was to determine whether there is an effect of mobile phone electromagnetic field emissions on the human electroencephalograph (EEG). EEG recordings from ten awake subjects were taken during exposure to radiofrequency (RF) emissions from a mobile phone positioned behind the head. Two experimental...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 临床试验,杂志文章,随机对照试验
doi：10.1007/BF03179176
更新日期：2003-12-01 00:00:00
abstract：:Fractal dimension has been proposed as a useful method for characterizing medical images. The fractal dimension is calculated from the average radial power spectrum of the image. However, simpler methods of calculation have been proposed. This paper examines a very simple and easily implemented method which has been p...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：
更新日期：1991-09-01 00:00:00
abstract：:The purpose of this paper is to describe an outline of a proton therapy system in Nagoya Proton Therapy Center (NPTC). The NPTC has a synchrotron with a linac injector and three treatment rooms: two rooms are equipped with a gantry and the other one is equipped with a fixed horizontal beamline. One gantry treatment ro...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/s13246-016-0456-8
更新日期：2016-09-01 00:00:00
abstract：:Non-linear loading of the utilities supply introduced significant electromagnetic field (EMF) interference severe enough to disrupt electrocardiograph (ECG) monitoring and recordings in the new Emergency Department (ED) at the Royal Melbourne Hospital (RMH). This interference was evident even though standard Mu-metal ...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/BF03178643
更新日期：2009-09-01 00:00:00
abstract：:A new era has arrived for the Biomedical Engineering Department at the Royal Women's Hospital in Melbourne. We have developed a system to qualitatively test for intermittent or unconfirmed faults, associated with Bear Cub ventilators. Where previous testing has been inadequate, computer logging is now used to interfac...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：
更新日期：1994-06-01 00:00:00
abstract：:Obesity management is a key point during cardiac rehabilitation. The effect of new index, waist circumference (WC), in the obesity management of cardiac rehabilitation is not clear yet. Therefore, our study compared the WC index to the body mass index (BMI) in the evaluation of obesity management for the patients with...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 临床试验,杂志文章
doi：10.1007/s13246-016-0471-9
更新日期：2016-12-01 00:00:00
abstract：:Gating is a relatively new and potentially useful therapeutic addition to external beam radiotherapy applied to regions affected by intra-fraction motion. The impact was of gating on treatment margins, image artifacts, and volume and positional accuracy was investigated by CT imaging of sinusoidally moving spheres. Th...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/BF03178368
更新日期：2002-03-01 00:00:00
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/s13246-014-0245-1
更新日期：2014-03-01 00:00:00
abstract：:Most of the human head models used in dipole localisation research, which have been reported in the literature to date, assume a simplified cranial structure wherein the head is modelled as a set of distinct homogenous tissue compartments. The inherent inhomogeneity of the tissues has so far been ignored in these mode...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/BF03178283
更新日期：2001-03-01 00:00:00
abstract：:The Resonant Recognition Model (rrm) uses digital signal processing methods to investigate protein structure-function; and links the biological function of protein families to unique characteristic frequencies. The rrm originally used a single set of variables: the electron ion interaction potential (EIIP). Here the r...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：
更新日期：1995-12-01 00:00:00
abstract：:The effect of radiation in regard to breast carcinogenesis is well studied and analysed from data from atomic bomb survivors, patients treated for acute mastitis and tuberculosis patients monitored by fluoroscopy. Therefore the radiation received by the untreated breast during breast irradiation of the other breast, i...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/BF03178353
更新日期：2001-06-01 00:00:00
abstract：:Monte Carlo modelling of particle transport problems in medical radiation physics offers significant advantages over other techniques. Experiments can be performed without having to set up the physical situation, and "impossible" experiments can be performed, such as labelling multiple-scattered particles or simulatin...
journal_title：Australasian physical & engineering sciences in medicine
pub_type：
doi：
更新日期：1990-09-01 00:00:00
abstract：:Rats are often used in the electromagnetic field (EMF) exposure experiments. In the study for the effect of 900 MHz EMF exposure on learning and memory in SD rats, the specific absorption rate (SAR) and the temperature rise in the rat head are numerically evaluated. The digital anatomical model of a SD rat is reconstr...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/s13246-013-0202-4
更新日期：2013-06-01 00:00:00
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journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/s13246-017-0558-y
更新日期：2017-09-01 00:00:00
abstract：:Conventional laser accelerated proton beam has broad energy spectra. It is not suitable for clinical use directly, so it is necessary for employing energy selection system. However, in the conventional laser accelerated proton system, the intensity of the proton beams in the low energy regime is higher than that in th...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/s13246-014-0292-7
更新日期：2014-12-01 00:00:00
abstract：:Given that there is increasing recognition of the effect that sub-millimetre changes in collimator position can have on radiotherapy beam dosimetry, this study aimed to evaluate the potential variability in small field collimation that may exist between otherwise matched linacs. Field sizes and field output factors we...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/s13246-015-0349-2
更新日期：2015-06-01 00:00:00
abstract：:The angular distribution for electron beams produced by the Siemens KD-2 linear accelerator has been found by simulating electron transport through the scattering foils and air using two methods: Fermi-Eyges multiple Coulomb scattering calculations, and EGS4 Monte Carlo simulations. Fermi-Eyges theory gives solutions ...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：
更新日期：1994-09-01 00:00:00
abstract：:The quality of phantom materials is crucial for accurate dosimetry in radiotherapy. A wide range of factors such as density, electron density and elemental composition can influence the radiation properties, and hence the absorbed dose, of materials. New materials can be tested by direct measurements which requires co...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：
更新日期：1993-09-01 00:00:00
abstract：:Regular checks on the performance of radiotherapy treatment units are essential and a variety of protocols has been published. These protocols identify that the determination of isocentre must be accurate and unambiguous since both the localization of a radiation field on a patient and positioning aids are referenced ...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/BF03178670
更新日期：2004-09-01 00:00:00
abstract：:Accuracy of dwell position and reproducibility of dwell time are critical in high dose rate (HDR) brachytherapy. A phantom was designed to verify dwell position and dwell time reproducibility for an Ir-192 HDR stepping source using Computed Radiography (CR). The central part of the phantom, incorporating thin alternat...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/s13246-012-0138-0
更新日期：2012-09-01 00:00:00
abstract：:Gravity associated with postural changes has a strong bearing on haemodynamics of blood flow in arteries. Its effect on stenosed cases has not been widely investigated. In the present study, variation observed in blood flow during postural changes is investigated for different conditions like standing, sleeping and he...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：10.1007/s13246-014-0246-0
更新日期：2014-03-01 00:00:00
abstract：:A solid water breast phantom with a lung equivalent material was constructed to investigate interface effects of 6 MV tangential photon fields. The phantom was built so that Thermo-luminescence Dosimeters (TLD) could be used for comparison to a pencil beam and Equivalent Tissue-Air-Ratio (ETAR) algorithms. The investi...
journal_title：Australasian physical & engineering sciences in medicine
pub_type： 杂志文章
doi：
更新日期：1998-03-01 00:00:00
