Abstract：
:The present study describes a new methodological approach which allows the separate analysis and quantitative determination of the viscous and elastic components of human hair using a computerised experimental system. In a first series of experiments subsequent to the estimation of the cross-sectional surface area of the cuticle, the cortex and the medulla, the viscoelastic response of hair (considered as a homogeneous material) and of its cortex were determined in ten hair specimens derived from the same human subject. Statistically significant differences were found between hair and its cortex with regard to the values of the modulus of elasticity, limit of linearity and post-yield slope. In a second series of experiments the viscoelastic parameters of hair and its cortex were separately determined in 100 hair specimens derived from ten healthy human subjects (ten specimens from each subject). It was found that the dispersion of the values of modulus of elasticity, limit of linearity and post-yield slope of the cortex was significantly reduced compared with that of the hair. Our results indicate that the pattern of the viscoelastic parameters of human hair cortex, which strongly depends on its microstructural features, may be regarded as a more reliable and sensitive diagnostic marker than that of hair in various structural and functional hair disorders.
journal_name
Med Biol Eng Computjournal_title
Medical & biological engineering & computingauthors
Nikiforidis G,Balas C,Tsambaos Ddoi
10.1007/BF02446198keywords:
subject
Has Abstractpub_date
1992-01-01 00:00:00pages
83-8issue
1eissn
0140-0118issn
1741-0444journal_volume
30pub_type
杂志文章abstract：:The paper deals with the influence of mains interference on time coherent averaging using an internal trigger. The general distribution of the time jitter is derived and applied to a simplified signal. The authors prove that no amount of averaging can do away with this type of interference. Finally, the deformation th...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/BF02457827
更新日期：1992-09-01 00:00:00
abstract：:The mechanical impedance of the ankle joint during electrical stimulation of the soleus is studied by applying constant-velocity 10 degrees angular perturbations to the ankle and measuring the resultant torque. Both neurologically intact subjects and spinal cord injured subjects are tested. Lumped, piecewise linear mo...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/BF02512522
更新日期：1994-05-01 00:00:00
abstract：:In a previous paper we demonstrated that the linear portion of the pressure-velocity loop (PU-loop) corresponding to early systole could be used to calculate the local wave speed. In this paper we extend this work to show that determination of the time at which the PU-loop first deviates from linearity provides a conv...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-007-0241-7
更新日期：2007-12-01 00:00:00
abstract：:This article presents a novel approach of edged and edgeless object-shape recognition and 3D reconstruction from gradient-based analysis of tactile images. We recognize an object's shape by visualizing a surface topology in our mind while grasping the object in our palm and also taking help from our past experience of...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-014-1142-1
更新日期：2014-04-01 00:00:00
abstract：:Spontaneous activity of specific regions (e.g., the Sinoatrial node, SAN) is essential for the normal activation sequence of the heart and also serve as a primary means of modulating cardiac rate by sympathetic tone and circulating catecholamines. The mechanisms of how a small SAN region can electrically drive a much ...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章,评审
doi：10.1007/s11517-006-0102-9
更新日期：2007-02-01 00:00:00
abstract：:Over a period of some years, the components of a system for discerning erosion on children's teeth have been progressively developed, for use in an extensive project seeking correlations between erosion and various perceived risk factors. The aim was the detection of minute levels of erosion, based on mappings of the ...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/BF02348090
更新日期：2003-07-01 00:00:00
abstract：:In electrocardiographic imaging (ECGI), one solves the inverse problem of electrocardiography (ECG) to reconstruct equivalent cardiac sources based on the body surface potential measurements and a mathematical model of the torso. Due to attenuation and spatial smoothing within the torso, this inverse problem is ill-po...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-019-02018-6
更新日期：2019-10-01 00:00:00
abstract：:Determination of the adequacy of dialysis is a routine but crucial procedure in patient evaluation. The total dialysis dose, expressed as Kt/V, has been widely recognised to be a major determinant of morbidity and mortality in haemodialysed patients. Many different factors influence the correct determination of Kt/V, ...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/BF02348080
更新日期：2003-07-01 00:00:00
abstract：:We introduce a novel method for an automatic classification of subjects to those with or without neuromuscular disorders. This method is based on multiscale entropy of recorded surface electromyograms (sEMGs) and support vector classification. The method was evaluated on a single-channel experimental sEMGs recorded fr...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-010-0629-7
更新日期：2010-08-01 00:00:00
abstract：:The aim of the study was to compare experimentally conduction velocity (CV) estimates obtained with different estimation methods based on surface electromyogram (EMG) signals detected using five spatial filters. The filters investigated were the longitudinal single and double differential, transverse single and double...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/BF02348440
更新日期：2003-05-01 00:00:00
abstract：:Single-ventricle anomaly is a hereditary heart disease that is characterized by anatomical malformations. The main consequence of this malformation is desaturated blood flow, which without proper treatment increases the risk of death. The classical treatment is based on a three-stage palliative procedure which should ...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-016-1499-4
更新日期：2017-02-01 00:00:00
abstract：:Neuronal excitability is determined in a complex way by several interacting factors, such as membrane dynamics, fibre geometry, electrode configuration, myelin impedance, neuronal terminations[Formula: see text] This study aims to increase understanding in excitability, by investigating the impact of these factors on ...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-018-1799-y
更新日期：2018-09-01 00:00:00
abstract：:A simple objective screening method for diagnosis of the atrial septal defect (ASD) is needed. Acoustic signals were collected from 61 children with ASD and 60 with a physiological murmur. The second heart sound (S2) and the spectrum of systolic murmur were analysed. A statistical model was designed using stepwise log...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-006-0094-5
更新日期：2006-09-01 00:00:00
abstract：:An efficient and novel modeling approach is proposed in this paper for identifying proteins or genes involved in melanoma skin cancer. Two types of classifiers are modeled, based on the chemical structure and hydropathy property of amino acids. These classifiers are further implemented using NI LabVIEW-based hardware ...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-020-02241-6
更新日期：2020-10-01 00:00:00
abstract：:A technique to obtain the spacing distribution of macro- and microstructures of hypercholestrolemic liver, lymphoidlucosed liver, rhinosporidium of man and ethmoidal tumour of bovine is presented. The method uses signal processing of spatially averaged spectra of ultrasonic backscattering from tissues in the frequency...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/BF02442608
更新日期：1990-11-01 00:00:00
abstract：:The relation is investigated between stimulus frequency, stimulus pulse amplitude and the neural damage induced by continuous stimulation of the cat's sciatic nerve. The chronically implanted electrodes were pulsed continuously and the effects of the electrical stimulation were quantified as the amount of early axonal...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/BF02510526
更新日期：1995-05-01 00:00:00
abstract：:In acute experiments the sciatic nerve of the rat is electrically stimulated to induce fatigue in the medial Gastrocnemius muscle. Fatigue tests are carried out using intermittent stimulation of different compartments (sequential) or a single compartment (synchronous) of the sciatic nerve. The activation of different ...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/BF02530036
更新日期：1997-05-01 00:00:00
abstract：:Portable biomedical instrumentation has become an important part of diagnostic and treatment instrumentation, including telemedicine applications. Low-voltage and low-power design tendencies prevail. Modern battery cell voltages in the range of 3-3.6 V require appropriate circuit solutions. A two-electrode biopotentia...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/BF02344642
更新日期：2004-03-01 00:00:00
abstract：:The aim of this study was to develop a radiation-free method to measure gastric emptying. Such a method would be useful e.g. for patients who need repeated measurements and in pregnancy. Ferrimagnetic particles (gamma-Fe2O3), ingested within a solid test meal (pancakes), were magnetised by an applied magnetic field. A...
journal_title：Medical & biological engineering & computing
pub_type： 临床试验,杂志文章
doi：10.1007/BF02522849
更新日期：1998-01-01 00:00:00
abstract：:In the case of female breast cancer, a breast-conserving excision is often desirable. This surgery is based on preoperatively gathered MRI, mammography, and sonography images. These images are recorded in multiple patient positions, e. g., 2D mammography images in standing position with a compressed breast and 3D MRI ...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-019-01977-0
更新日期：2019-07-01 00:00:00
abstract：:Biomechanical models used to estimate joint loads often predict that antagonistic muscles are inactive or underestimate their contributions [3, 5]. This can result in systematic underestimation of muscle force predictions and joint contact forces. To test the feasibility of employing an empirical co-activation ratio t...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-013-1081-2
更新日期：2014-03-01 00:00:00
abstract：:In daily life, a person's gait-an important marker for his/her health status-is usually assessed using inertial sensors fixed to lower limbs or trunk. Such sensor locations are not well suited for continuous and long duration measurements. A better location would be the wrist but with the drawback of the presence of p...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-017-1621-2
更新日期：2017-10-01 00:00:00
abstract：:High-intensity noises are a health hazard for industrial workers, and hearing protection is necessary to prevent hearing loss. Passive methods, such as ear muffs, are ineffective against low-frequency noise. Moreover, many hearing-impaired workers must wear hearing aids to enable communication at their workplace, and ...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/BF02430951
更新日期：2005-11-01 00:00:00
abstract：:Generation of a large number of cells belonging to the cardiac pacemaker system would constitute an important step towards their utilization as a biological cardiac pacemaker system. The aim of the present study was to identify factors, which might induce transformation of a heterogenous population of fetal cardiomyoc...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-007-0164-3
更新日期：2007-02-01 00:00:00
abstract：:The heart rate variability (HRV) is an indicator of the subject homeostasis alterations. For a healthy individual, the HRV shows a nonlinear behavior, thus requiring a nonlinear approach to provide additional information about HRV dynamics. In this work, the nonlinear techniques, central tendency measure (CTM) and sec...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-015-1390-8
更新日期：2015-11-01 00:00:00
abstract：:Density assessment and lesion localization in breast MRI require accurate segmentation of breast tissues. A fast, computerized algorithm for volumetric breast segmentation, suitable for multi-centre data, has been developed, employing 3D bias-corrected fuzzy c-means clustering and morphological operations. The full br...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-016-1484-y
更新日期：2017-01-01 00:00:00
abstract：:The visco-elastic properties of living cells, measured to date by various authors, vary considerably, depending on the experimental methods and/or on the theoretical models used. In the present study, two mechanisms thought to be involved in cellular visco-elastic responses were analysed, based on the idea that the cy...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/BF02349982
更新日期：2003-11-01 00:00:00
abstract：:Performance evaluations of ion-selective field-effect transistors (ISFETs) have been carried out using both quality-control materials and whole arterial blood samples. Comparison of the results from these evaluations suggests that the whole blood evaluation may be more useful when assessing the value of particular sen...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/BF02442678
更新日期：1990-05-01 00:00:00
abstract：:Biological variation in branching patterns is likely to affect perfusion of tissue. To assess the fundamental consequences of branching characteristics, 50 stochastic asymmetrical coronary trees and one non-stochastic symmetrical branching tree were generated. In the stochastic trees, area growth, A, at branching poin...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-006-0139-9
更新日期：2007-01-01 00:00:00
abstract：:While matrix remodeling plays a key role in vascular physiology and pathology, the underlying mechanisms have remained incompletely understood. We studied the remodeling of collagen matrices by individual vascular smooth muscle cells (SMCs), clusters and monolayers. In addition, we focused on the contribution of trans...
journal_title：Medical & biological engineering & computing
pub_type： 杂志文章
doi：10.1007/s11517-012-0916-6
更新日期：2012-07-01 00:00:00
