Abstract：
:We propose a multifrequency energy transmission scheme for annular phased arrays in deep-body hyperthermia. The problem of frequency dependent resonance effects reported in hyperthermia phantom calibration studies, leading to skewed energy deposition patterns and unwanted energy maxima (hot spots), is addressed by comparing broadband energy transmission with conventional monofrequency excitation. A heating system, including microstrip spiral applicators placed at a cylindrical surface in four quadrants, was designed to study this new concept in a homogeneous phantom. The system includes an option to select three cw tones for simultaneous transmission within a frequency range from 232 to 936 MHz. Quantitative analyzes of E-field probe-scan data, generated in a 6 g/L saline phantom and evaluated by three figures of merits defined, demonstrate the possibility of adding up power in the focus site while smearing secondary maxima outside this volume. Random selection of the three sinusoids within this band shows a probability of 0.7 to improve performance compared to the conventional single-frequency heating. A numerical study of the electromagnetic problem was also implemented using the FD-TD method. Analysis shows acceptable agreement between measured and simulated two-dimensional energy deposition patterns.
journal_name
Ann Biomed Engjournal_title
Annals of biomedical engineeringauthors
Jacobsen S,Melandsø Fdoi
10.1114/1.1430749subject
Has Abstractpub_date
2002-01-01 00:00:00pages
34-43issue
1eissn
0090-6964issn
1573-9686journal_volume
30pub_type
杂志文章abstract：:This experimental work focused on the sensor selection for the development of a needle-like instrument to treat small isolated cartilage defects with hydrogels. The aim was to identify the most accurate and sensitive imaging method to determine the location and size of defects compared to a gold standard (µCT). Only i...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-018-2073-z
更新日期：2018-11-01 00:00:00
abstract：:This study is aimed at refining our understanding of the role of vortex formation at mitral mechanical heart valve (MHV) closure and its association with the high intensity transient signals (HITS) seen in echocardiographic studies with MHV recipients. Previously reported numerical results described a twofold process ...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-007-9293-y
更新日期：2007-07-01 00:00:00
abstract：:To better understand oxygen utilization by the retina, a mathematical model of oxygen diffusion and consumption in the cat outer, avascular retina was developed by analyzing previously recorded profiles of oxygen tension (PO2) as a function of retinal depth. Simple diffusion modelling of the oxygen distribution throug...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/BF02368415
更新日期：1990-01-01 00:00:00
abstract：:In vitro and in vivo studies were conducted on omega-3 fatty acid-derived biomaterials to determine their utility as an implantable material for adhesion prevention following soft tissue hernia repair and as a means to allow for the local delivery of antimicrobial or antibiofilm agents. Naturally derived biomaterials ...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-015-1489-y
更新日期：2016-03-01 00:00:00
abstract：:Collagen is known to be a viscoelastic material and therefore is an important source of time dependent behavior in soft tissue. Though there are material models for soft tissue that rely on properties and structure of constituent collagen fibers, such models generally utilize only the elastic properties of collagen, a...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-006-9124-6
更新日期：2006-07-01 00:00:00
abstract：:The statistical distribution of von Mises stress in the trabeculae of human vertebral cancellous bone was estimated using large-scale finite element models. The goal was to test the hypothesis that average trabecular von Mises stress is correlated to the maximum trabecular level von Mises stress. The hypothesis was pr...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1114/1.1318928
更新日期：2000-01-01 00:00:00
abstract：:Magnetic nanoparticle (mNP) based thermal therapies have demonstrated relevance in the clinic, but effective application requires an understanding of both its strengths and limitations. This study explores two critical limitations for clinical use: (1) maximizing localized mNP heating, while avoiding bulk heating due ...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-012-0633-1
更新日期：2013-01-01 00:00:00
abstract：:Early stage changes in hypertensive arteries have a significant effect on the long-term adaptation of the arteries. Compared to the long-term adaptation, little is known about the early dimensional and functional changes in hypertensive arteries in the first few days of hypertension. To study the early stage changes i...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1114/1.1376391
更新日期：2001-06-01 00:00:00
abstract：:A two-dimensional sheet model was used to study the dynamics of reentry around a zone of functional block. The sheet is a set of parallel, continuous, and uniform cables, transversely interconnected by a brick-wall arrangement of fixed resistors. In accord with experimental observations on cardiac tissue, longitudinal...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/BF02368286
更新日期：1994-11-01 00:00:00
abstract：:Presented is a discussion of steps towards the creation of a database of the microcirculation encompassing anatomical and functional experimental data, and conceptual and computational models. The discussion includes issues of database utility, organization, data deposition, and linkage to other databases. The databas...
journal_title：Annals of biomedical engineering
pub_type：
doi：10.1114/1.112
更新日期：1998-11-01 00:00:00
abstract：:We propose a mathematical model for analyses of the elastic properties of the wall of the outer hair cell (OHC) in the inner ear. The model reflects the properties of the major components of the OHC wall: the subsurface cisternae, the cortical lattice, the plasma membrane, and the radial pillars. The wall is treated a...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1114/1.87
更新日期：1998-01-01 00:00:00
abstract：:Correct development of neuronal tracts requires the coordination of multiple permissive and inhibitory signals. By generating an in vitro microenvironment using soft lithography and microfluidic techniques, multiple guidance cues can be presented in a spatially defined way. Here we evaluated how neurites of dorsal roo...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-008-9486-z
更新日期：2008-06-01 00:00:00
abstract：:The geometric and hemodynamic characteristics of the left and right vertebral arteries (LVA, RVA) of six healthy volunteers were investigated for the supine (S) and the prone position (P) a common sleeping posture with head rotation. MRI images were used to reconstruct the subject specific three-dimensional solid mode...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-015-1340-5
更新日期：2015-06-01 00:00:00
abstract：:Fingertips wrinkle due to long exposure to water. The biological reason for this morphological change is unclear and still not fully understood. There are two main hypotheses for the underlying mechanism of fingertip wrinkling: the 'shrink' model (in which the wrinkling is driven by the contraction of the lower layers...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-016-1764-6
更新日期：2017-04-01 00:00:00
abstract：:Quantifying injury tolerance for concussion is complicated by variability in the type, severity, and time course of post-injury physiological and behavioral changes. The current study outlined acute and chronic changes in behavioral metrics following rotational acceleration-induced concussion in rats. The Medical Coll...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-016-1647-x
更新日期：2016-11-01 00:00:00
abstract：:Experimental studies have shown that cardiac fibroblasts are electrically inexcitable, but can contribute to electrophysiology of myocardium in various manners. The aim of this computational study was to give insights in the electrophysiological role of fibroblasts and their interaction with myocytes. We developed a m...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-007-9405-8
更新日期：2008-01-01 00:00:00
abstract：:We developed muscle-tendon models incorporating Hill-type structure and length-dependent coupling between activation and velocity. The models were evaluated in electrically stimulated cat soleus muscles. Dynamic model parameters were estimated by a nonlinear parameter estimation algorithm from input-output data obtain...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1114/1.93
更新日期：1998-05-01 00:00:00
abstract：:The pericellular matrix (PCM) is a region of tissue that surrounds chondrocytes in articular cartilage and together with the enclosed cells is termed the chondron. Previous studies suggest that the mechanical properties of the PCM, relative to those of the chondrocyte and the extracellular matrix (ECM), may significan...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-005-4479-7
更新日期：2005-10-01 00:00:00
abstract：:A wide range of length and time scales are relevant to pharmacology, especially in drug development, drug design and drug delivery. Therefore, multiscale computational modeling and simulation methods and paradigms that advance the linkage of phenomena occurring at these multiple scales have become increasingly importa...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章,评审
doi：10.1007/s10439-016-1563-0
更新日期：2016-09-01 00:00:00
abstract：:Arteries are composed of multiple constituents that endow the wall with proper structure and function. Many vascular diseases are associated with prominent mechanical and biological alterations in the wall constituents. In this study, planar biaxial tensile test data of elastase-treated porcine aortic tissue (Chow et ...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-012-0733-y
更新日期：2013-07-01 00:00:00
abstract：:An adaptive neural network model that exhibits the optimality and homeostasis characteristics of the respiratory control system is described. Based upon the Hopfield network structure and a postulated Hebb-like respiratory synapse with correlational short-term potentiation, the model is capable of mimicking the normal...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/BF02584332
更新日期：1993-09-01 00:00:00
abstract：:Disease and injury perturb the balance of processes associated with inflammation and tissue remodeling, resulting in positive feedback loops, exacerbation of disease and compromised tissue repair. Conversely, under homeostatic healthy conditions, these processes are tightly regulated through the expansion and/or recru...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章,评审
doi：10.1007/s10439-014-1125-2
更新日期：2015-03-01 00:00:00
abstract：:The local dilation of the infrarenal abdominal aorta, termed an abdominal aortic aneurysm (AAA), is often times asymptomatic and may eventually result in rupture-an event associated with a significant mortality rate. The estimation of in-vivo stresses within AAAs has been proposed as a useful tool to predict the likel...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-008-9490-3
更新日期：2008-06-01 00:00:00
abstract：:It is well known that neutrophils take much longer to traverse the pulmonary capillary bed than erythrocytes, and this is likely due to differences in the structure and rheology of the cells. In this study, we simulate the transit of a neutrophil in a capillary using a Newtonian drop model and a viscoelastic drop mode...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-007-9286-x
更新日期：2007-05-01 00:00:00
abstract：:This experiment investigates the validity of six thermometers with different measuring sensors, operation and site of application, to estimate core temperature (Tc) in comparison to an ingestible thermometric sensor based on quartz crystal technology. Measurements were obtained before, during and after exercise in the...
journal_title：Annals of biomedical engineering
pub_type： 临床试验,杂志文章
doi：10.1007/s10439-018-02115-x
更新日期：2019-01-01 00:00:00
abstract：:Poor prosthetic fit is often the result of heterotopic ossification (HO), a frequent problem following blast injuries for returning service members. Osseointegration technology offers an advantage for individuals with significant HO and poor socket tolerance by using direct skeletal attachment of a prosthesis to the d...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-010-0050-2
更新日期：2010-09-01 00:00:00
abstract：:The identification of the input to, or kernels of, a system using nonparametric representations and least-squares estimation is becoming increasingly popular. Nonparametric representations avoid making a priori assumptions about the input or having detailed knowledge about the system, and only need to guarantee known ...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1114/1.110
更新日期：1998-09-01 00:00:00
abstract：:This paper reports the design, manufacturing, and characterization of a new bioreactor dedicated to the development of tissue-engineered heart valve substitutes. First, a comprehensive review of the state of the art in bioreactors is presented and a rigorous classification is put forward. The existing bioreactors foun...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-009-9646-9
更新日期：2009-04-01 00:00:00
abstract：:Mechanical properties of the cardiac tissue play an important role in normal heart function. The goal of this study was to determine the passive mechanical properties of all heart chambers through a paired comparison study in an ovine model. Ovine heart was used due its physiological and anatomical similarities to hum...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/s10439-016-1658-7
更新日期：2016-11-01 00:00:00
abstract：:Polycrystalline silicon (poly-Si) micromechanical structures can be made by selectively etching an underlying sacrificial oxide layer. Advantages of this micromachining technique are its simplicity and compatibility with conventional integrated-circuit processing. Compressive internal stress in poly-Si films constrain...
journal_title：Annals of biomedical engineering
pub_type： 杂志文章
doi：10.1007/BF02584269
更新日期：1986-01-01 00:00:00
