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PubMed2006

Application of a simple likelihood ratio approximant to protein sequence classification.

MOTIVATION: Likelihood ratio approximants (LRA) have been widely used for model comparison in statistics. The present study was undertaken in order to explore their utility as a scoring (ranking) function in the classification of protein sequences. RESULTS: We used a simple LRA-based on the maximal similarity (or minimal distance) scores of the two top ranking sequence classes. The scoring methods (Smith-Waterman, BLAST, local alignment kernel and compression based distances) were compared on datasets designed to test sequence similarities between proteins distantly related in terms of structure or evolution. It was found that LRA-based scoring can significantly outperform simple scoring methods.

Algorithms↗
PubMed2003

Measuring the elastic modulus of ex vivo small tissue samples.

Over the past decade, several methods have been proposed to image tissue elasticity based on imaging methods collectively called elastography. While progress in developing these systems has been rapid, the basic understanding of tissue properties to interpret elastography images is generally lacking. To address this limitation, we developed a system to measure the Young's modulus of small soft tissue specimens. This system was designed to accommodate biological soft tissue constraints such as sample size, geometry imperfection and heterogeneity. The measurement technique consists of indenting an unconfined small block of tissue while measuring the resulting force. We show that the measured force-displacement slope of such a geometry can be transformed to the tissue Young's modulus via a conversion factor related to the sample's geometry and boundary conditions using finite element analysis. We also demonstrate another measurement technique for tissue elasticity based on quasi-static magnetic resonance elastography in which a tissue specimen encased in a gelatine-agarose block undergoes cyclical compression with resulting displacements measured using a phase contrast MRI technique. The tissue Young's modulus is then reconstructed from the measured displacements using an inversion technique. Finally, preliminary elasticity measurement results of various breast tissues are presented and discussed.

Adult↗
PubMed2025

SKiM: accurately classifying metagenomic ONT reads in limited memory.

MOTIVATION: Oxford Nanopore Technologies' devices, such as MinION, permit affordable, real-time DNA sequencing, and come with targeted sequencing capabilities. Such capabilities create new challenges for metagenomic classifiers that must be computationally efficient yet robust enough to handle potentially erroneous DNA reads, while ideally inspecting only a few hundred bases of a read. Currently available DNA classifiers leave room for improvement with respect to classification accuracy, memory usage, and the ability to operate in targeted sequencing scenarios. RESULTS: We present SKiM: Short K-mers in Metagenomics, a new lightweight metagenomic classifier designed for ONT reads. Compared to state-of-the-art classifiers, SKiM requires only a fraction of memory to run, and can classify DNA reads with higher accuracy after inspecting only their first few hundred bases. To achieve this, SKiM introduces new data compression techniques to maintain a reference database built from short k-mers, and treats classification as a statistical testing problem. AVAILABILITY AND IMPLEMENTATION: SKiM source code, documentation, and test data are available from: https://gitlab.com/SCoRe-Group/skim.

Metagenomics↗
PubMed2006

Segmentation of bone CT images and assessment of bone structure using measures of complexity.

A nondestructive and noninvasive method for numeric characterization (quantification) of the structural composition of human bone tissue has been developed and tested. In order to quantify and to compare the structural composition of bones from 2D computed tomography (CT) images acquired at different skeletal locations, a series of robust, versatile, and adjustable image segmentation and structure assessment algorithms were developed. The segmentation technique facilitates separation from cortical bone and standardizes the region of interest. The segmented images were symbol-encoded and different aspects of the bone structural composition were quantified using six different measures of complexity. These structural examinations were performed on CT images of bone specimens obtained at the distal radius, humeral mid-diaphysis, vertebral body, femoral head, femoral neck, proximal tibia, and calcaneus. In addition, the ability of the noninvasive and nondestructive measures of complexity to quantify trabecular bone structure was verified by comparing them to conventional static histomorphometry performed on human fourth lumbar vertebral bodies. Strong correlations were established between the measures of complexity and the histomorphometric parameters except for measures expressing trabecular thickness. Furthermore, the ability of the measures of complexity to predict vertebral bone strength was investigated by comparing the outcome of the complexity analysis of the CT images with the results of a biomechanical compression test of the third lumbar vertebral bodies from the same population as used for histomorphometry. A multiple regression analysis using the proposed measures including structure complexity index, structure disorder index, trabecular network index, index of a global ensemble, maximal L-block, and entropy of x-ray attenuation distribution revealed an excellent relationship (r=0.959, r2=0.92) between the measures of complexity and compressive bone strength. In conclusion, the image segmentation techniques and the assessment of bone architecture by measures of complexity have been successfully applied to analyze high-resolution peripheral quantitative computed tomography (pQCT) and CT images obtained from the distal radius, humeral mid-diaphysis, third and fourth lumbar vertebral bodies, proximal femur, proximal tibia, and calcaneus. The proposed approach is of broad interest as it can be applied for the quantification of structures and textures originating from different imaging modalities in other fields of science.

Aged↗
PubMed2006

From 2D PET to 3D PET: issues of data representation and image reconstruction.

Positron emission tomography (PET), intrinsically a 3D imaging technique, was for a long time exclusively operated in 2D mode, using septa to shield the detectors from photons emitted obliquely to the detector planes. However, the use of septa results in a considerable loss of sensitivity. From the late 1980s, significant efforts have been made to develop a methodology for the acquisition and reconstruction of 3D PET data. This paper focuses on the differences between data acquisition in 2D and 3D mode, especially in terms of data set sizes and representation. Although the real time data acquisition aspect in 3D has been mostly solved in modern PET scanner systems, there still remain questions on how to represent and how to make best use of the information contained in the acquired data sets. Data representation methods, such as list-mode and matrix-based methods, possibly with additional compression, will be discussed. Moving from 2D to 3D PET has major implications on the way these data are reconstructed to images. Two fundamentally different approaches exist, the analytical one and the iterative one. Both, at different expenses, can be extended to directly handle 3D data sets. Either way the computational burden increases heavily compared to 2D reconstruction. One possibility to benefit from the increased sensitivity in 3D PET while sticking to high-performance 2D reconstruction algorithms is to rebin 3D into 2D data sets. The value of data rebinning will be explored. An ever increasing computing power and the concept of distributed or parallel computing have made direct 3D reconstruction feasible. Following a short review of reconstruction methods and their extensions to 3D, we focus on numerical aspects that improve reconstruction performance, which is especially important in solving large equation systems in 3D iterative reconstruction. Finally exemplary results are shown to review the properties of the discussed algorithms. This paper concludes with an overview on future trends in data representation and reconstruction.

Humans↗
PubMed2004

Mechanics of transient platelet adhesion to von Willebrand factor under flow.

A primary and critical step in platelet attachment to injured vascular endothelium is the formation of reversible tether bonds between the platelet glycoprotein receptor Ibalpha and the A1 domain of surface-bound von Willebrand factor (vWF). Due to the platelet's unique ellipsoidal shape, the force mechanics involved in its tether bond formation differs significantly from that of leukocytes and other spherical cells. We have investigated the mechanics of platelet tethering to surface-immobilized vWF-A1 under hydrodynamic shear flow. A computer algorithm was used to analyze digitized images recorded during flow-chamber experiments and track the microscale motions of platelets before, during, and after contact with the surface. An analytical two-dimensional model was developed to calculate the motion of a tethered platelet on a reactive surface in linear shear flow. Through comparison of the theoretical solution with experimental observations, we show that attachment of platelets occurs only in orientations that are predicted to result in compression along the length of the platelet and therefore on the bond being formed. These results suggest that hydrodynamic compressive forces may play an important role in initiating tether bond formation.

Antigens↗
PubMed2001

Recognizing spinal cord emergencies.

Physicians who work in primary care settings and emergency departments frequently evaluate patients with neck and back pain. Spinal cord emergencies are uncommon, but injury must be recognized early so that the diagnosis can be quickly confirmed and treatment can be instituted to possibly prevent permanent loss of function. The differential diagnosis includes spinal cord compression secondary to vertebral fracture or space-occupying lesion, spinal infection or abscess, vascular or hematologic damage, severe disc herniation and spinal stenosis. The most important information in the assessment of a possible spinal cord emergency comes from the history and the clinical evaluation. Physicians must look for "red flags"--key historical and clinical clues that increase the likelihood of a serious underlying disorder. In considering diagnostic tests, physicians should apply the principles outlined in an algorithm for the evaluation of low back pain prepared by the Agency for Healthcare Research and Quality (formerly the Agency for Health Care Policy and Research). Computed tomography and magnetic resonance imaging can clearly define anatomy, but these studies are costly and have a high false-positive rate. Referral of high-risk patients to a neurologist or spine specialist may be indicated.

Decision Trees↗
PubMed1998

[Abdominal trauma].

While a great part of the Anglo-American medical literature addresses the topic of penetrating trauma the German speaking countries rather publish on blunt abdominal injury. The presented paper discusses the strategic principles of acute clinical management of abdominal trauma on the combined basis of own research results and a comprehensive review of the literature. Blunt abdominal injuries in most cases from a part in the pattern of multiple trauma. The early, first-hours mortality is most often caused by severe traumatic brain injury or abdominal trauma with massive hemorrhage. The prehospital management of penetrating injuries is characterized rather by the concept of 'load and go', whereas the onscene stabilization of the patient with blunt abdominal injury should precede transport to the adequate hospital. On arrival in the accident and emergency room an immediate blood transfusion is recommended for hemodynamically unstable patients. If then a stabilization is not achieved, an emergency laparotomy should follow. Abdominal stab injuries should be explored by laparoscopy if an intraperitoneal lesion is suspected. If then the possibility of an intestinal lesion is present a laparotomy should be performed directly thereafter. Firearm injuries require open revision in almost all cases. The standard diagnostic technique in blunt abdominal trauma is sonography, assisted by computed tomography and, if indicated, angiography in hemodynamically stable patients. Isolated abdominal injuries without hemodynamic or coagulation disorders allow conservative treatment in the intensive care setting. In severe multiple trauma as well as in manifest shock even the smallest fluid detection should lead to laparotomy. The surgical treatment of splenic rupture is still a matter of discussion. Splenectomy is indicated in patients with severe concomitating injuries or shock whereas in the remainder of cases the total or partial preservation of the spleen should be pursued. Hepatic injuries offer a broad spectrum of operative interventions, ranging from superficial hemostatic measures over compression techniques like 'packing' and 'mesh-wrapping' to atypical and anatomical resections and to liver transplantation in exceptional cases. Lesions of tubular organs and the pancreas pose especially difficult diagnostical problems but regularly allow a rather easy operative treatment.

Abdominal Injuries↗
PubMed2005

A comparative study of the physicochemical properties of perfluorinated and hydrogenated amphiphiles.

In this work we studied and compared the physicochemical properties of perfluorinated (sodium perfluoroheptanoate, C7FONa, and perfluorooctanoate, C8FONa) and hydrogenated (sodium octanoate, C8HONa, decanoate, C10HONa, and dodecanoate, C12HONa) amphiphiles. First, we determined their Krafft points to study the solubility and appropriate temperature range of micellization of these compounds. The critical micelle concentration (cmc) and ionization degree of micellization (beta) as a function of temperature (T) were estimated from conductivity data. Plots of cmc vs T appear to follow the typical U-shaped curve with a minimum T(min). The results show that the surfactants with CF2/CH2 ratio of 1.5 between alkyl chains (C12HONa-C8FONa and C10HONa-C7FONa) have nearly the same minimum value for cmc against temperature. The comparison between the cmc of hydrogenated amphiphiles and the corresponding perfluorinated amphiphiles must be done at this point. Thermodynamic functions of micellization were obtained by applying different theoretical models and choosing the one that best fit our experimental data. Although perfluorinated and hydrogenated amphiphiles present similar thermodynamic behavior, we have found a variation of 1.3 to 1.7 in the CF2/CH2 ratio, which did not remain constant with temperature. In the second part of this study the apparent molar volumes and adiabatic compressibilities were determined from density and ultrasound velocity measurements. Apparent molar volumes at infinite dilution presented the ratio 1.5 between alkyl chains again. However, apparent molar volumes upon micellization for sodium perfluoroheptanoate indicated a different aggregation pattern.

Algorithms↗
PubMed2000

Electrophoretic deposition of polymer chains: a Monte Carlo study of density profile and conformation.

Effects of molecular weight (Lc) and field strength (E) on conformation of polymer chains and their density are investigated at the surface and bulk of a driven chain system in three dimensions with a Monte Carlo simulation. As the polymer chains deposit on the surface, a linear density gradient develops in low field. While the gradient becomes steeper on increasing the field in low Lc, onset of oscillation in the polymer density profile appears with higher Lc, above a characteristic value of field (Ec) which decreases with increasing molecular weight. The substrate coverage (theta j) exhibits a rapid increase on increasing the field and tends to decline at high fields. In the bulk, the polymer density decreases rapidly with the molecular weight while the substrate coverage (theta j) decays exponentially, theta j approximately e-beta Lc. The radius of gyration (Rg) of chains undergoes a crossover from SAW to rodlike conformation in the bulk on increasing the field. On the surface, chains are longitudinally compressed with a sub-SAW conformation, i.e., the scaling exponent v approximately 0.50-0.55 (Rg approximately Lc-v). Nonmonotonic response with opposite trend is observed in the variation of the longitudinal (minimum) and transverse (maximum) components of the radius of gyration with the field.

Algorithms↗
PubMed2005

Effects of three amplification strategies on speech perception by children with severe and profound hearing loss.

OBJECTIVE: Traditionally in the United Kingdom, children with severe and profound hearing loss have been fitted with linear, analog hearing aids. Fast-acting, wide-dynamic-range compression (WDRC) has been shown to give better discrimination of speech than linear amplification for moderately hearing-impaired young adults. For severe and profound hearing losses, higher compression ratios are needed. The resultant distortion of the temporal envelope and reduced modulation depth may offset improvements in audibility offered by WDRC. In this study, speech recognition and discrimination were assessed for severely and profoundly hearing-impaired children, using three different amplification strategies, including WDRC. DESIGN: Fifteen children (ages 7 to 15 yr) with severe and profound hearing loss were fitted bilaterally with high-power, multichannel compression hearing aids, incorporating one of three different amplification strategies: linear with peak clipping, linear with compression limiting, or WDRC. Output responses were matched to Desired Sensation Level (DSL i/o) targets. The children wore hearing aids programmed with each of the amplification strategies in turn, for at least 1 wk, in a counterbalanced order across children. After using a particular amplification strategy for at least 1 wk, speech perception tests were carried out. RESULTS: Speech scores on closed-set testing for the profound group showed significant benefit for WDRC over the other two algorithms. None of the other results showed a statistically significant effect of algorithm on speech performance. CONCLUSIONS: WDRC amplification sometimes led to better performance than linear amplification with peak clipping or output limiting, and it never led to poorer performance. Therefore, it appears to be safe to use well-designed WDRC for hearing-impaired children with severe or profound hearing loss.

Adolescent↗
PubMed1996

A comparison of adaptive and nonadaptive filters for reduction of power line interference in the ECG.

We have investigated the relative performance of an adaptive and nonadaptive 60-Hz notch filter applied to an ECG signal. We evaluated the performance of the two implementations with respect to adaptation rate (or transient response time), signal distortion, and implementation complexity. We also investigated the relative effect of adaptive and nonadaptive 60-Hz filtering on ECG data compression. With a 360 Hz sample rate and an adaptation time of approximately 0.3 s for a 1 mV 60-Hz signal, the adaptive implementation is less complex and introduces less noise, particularly in the ST-segment, into a typical ECG signal. When applied to ECG signals, prior to data compression by average beat subtraction and residual differencing, the residual signal resulting from the adaptively filtered signal had an average entropy 0.37 bits per sample (bps) lower than the unfiltered signal. The nonadaptive 60-Hz filter produced an average entropy decrease of 0.08 bps relative to the unfiltered ECG.

Algorithms↗
PubMed1993

Is bilateral lower extremity compression sonography useful and cost-effective in the evaluation of suspected pulmonary embolism?

OBJECTIVE: Because deep venous thrombosis is clinically linked with pulmonary embolism and often treated similarly, we sought to assess the usefulness of obtaining bilateral lower extremity compression sonograms when findings on ventilation-perfusion lung scans indicate a low or indeterminate probability of pulmonary embolism. Demonstration of deep venous thrombosis would provide a rationale for treating both pulmonary embolism and deep venous thrombosis. MATERIALS AND METHODS: Two hundred twenty-three consecutive patients with suspected pulmonary embolism had ventilation-perfusion lung scans and concurrent bilateral lower extremity compression sonograms; 34 also had pulmonary arteriography. RESULTS: In 75 cases, the results of ventilation-perfusion lung scanning indicated an indeterminate probability of pulmonary embolism. Evidence of thrombosis was seen on sonograms in 11 of these 75. In the remaining 64, 17 underwent pulmonary arteriography and four (24%) had pulmonary embolism. Findings on lung scans indicated a low probability of pulmonary embolism in 70 of 223 patients. Evidence of thrombosis was seen on sonograms in 11 of these 70. Five of the remaining 59 underwent pulmonary arteriography and one (20%) had pulmonary embolism. According to the 1993 Medicare Fee Schedule, if all 145 patients whose lung scans were nondiagnostic had sonography and only those with normal sonograms had pulmonary arteriography, the professional and hospital charges would be $359,552. If all 145 had pulmonary arteriography without sonography, the charges would be $395,031. CONCLUSION: If ventilation-perfusion lung scans indicate a low or an indeterminate probability of pulmonary embolism and bilateral lower extremity compression sonography is performed, only those patients with normal sonographic findings would need further study. Thus, 15% (22/145) of patients could be spared pulmonary arteriography, and the estimated savings in cost would be 9%.

Algorithms↗
PubMed2004

A three-dimensional finite element model of an adherent eukaryotic cell.

Mechanical stimulation is known to cause alterations in the behaviour of cells adhering to a substrate. The mechanisms by which forces are transduced into biological responses within the cell remain largely unknown. Since cellular deformation is likely involved, further understanding of the biomechanical origins of alterations in cellular response can be aided by the use of computational models in describing cellular structural behaviour and in determining cellular deformation due to imposed loads of various magnitudes. In this paper, a finite element modelling approach that can describe the biomechanical behaviour of adherent eukaryotic cells is presented. It fuses two previous modelling approaches by incorporating, in an idealised geometry, all cellular components considered structurally significant, i.e. prestressed cytoskeleton, cytoplasm, nucleus and membrane components. The aim is to determine if we can use this model to describe the non-linear structural behaviour of an adherent cell and to determine the contribution of the various cellular components to cellular stability. Results obtained by applying forces (in the picoNewton range) to the model membrane nodes suggest a key role for the cytoskeleton in determining cellular stiffness. The model captures non-linear structural behaviours such as strain hardening and prestress effects (in the region of receptor sites), and variable compliance along the cell surface. The role of the cytoskeleton in stiffening a cell during the process of cell spreading is investigated by applying forces to five increasingly spread cell geometries. Parameter studies reveal that material properties of the cytoplasm (elasticity and compressibility) also have a large influence on cellular stiffness. The computational model of a single cell developed here is proposed as one that is sufficiently complex to capture the non-linear behaviours of the cell response to forces whilst not being so complex that the parameters cannot be specified. The model could be very useful in computing cellular structural behaviour in response to various in vitro mechanical stimuli (e.g. fluid flow, substrate strain), or for use in algorithms that attempt to simulate mechanobiological processes.

Actin Cytoskeleton↗
PubMedDate not supplied

Imaging evaluation of suspected pulmonary embolism.

Venous thromboembolism (VTE) is a common disorder that is difficult to diagnose clinically but carries significant morbidity and mortality if untreated. Additionally, although demonstrated to be of benefit in cases of proven deep vein thrombosis (DVT) and pulmonary embolism (PE), anticoagulation therapy is not without risk. Because the clinical exam is known to be unreliable for the detection of both DVT and PE, many imaging modalities have been used in the diagnostic imaging algorithm for the detection of VTE, including chest radiography, ventilation/perfusion (V/Q) scintigraphy, pulmonary angiography, and recently, spiral computed tomography (CT) and magnetic resonance imaging (MRI). Chest radiographic findings in acute PE include focal oligemia, vascular enlargement, atelectasis, pleural effusions, and air space opacities representing pulmonary hemorrhage or infarction. The chest radiograph can occasionally be suggestive of PE but is more often nonspecifically abnormal. The main use of the chest radiograph in the evaluation of suspected PE is to exclude entities that may simulate PE and to assist in the interpretation of V/Q scintigraphy. Lower extremity venous compression ultrasonography (CU) is both sensitive and specific for the diagnosis of femoropopliteal DVT, and the value of negative CU results has been established in outcomes studies. However, the reliability of CU for the detection of isolated calf vein thrombosis is not well established, and the clinical significance of such thrombi is debatable. Additional methods such as color and spectral Doppler analysis are also useful in the diagnostic evaluation of DVT but are best considered as adjuncts to the conventional CU examination rather than as primary diagnostic modalities themselves. Compression ultrasonography and Doppler techniques are useful in the evaluation of suspected upper extremity DVT; spectral Doppler waveform analysis is particularly useful to assess for the patency of veins that cannot be directly visualized and compressed with conventional gray-scale sonography. V/Q scintigraphy has been the initial modality obtained in patients suspected of PE for a number of years. Although many studies have investigated the role of V/Q scintigraphy in the evaluation of VTE, the Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED) study has provided the most useful information regarding the utility of V/Q scintigraphy in this setting. A high probability scan interpretation is sufficient justification to institute anticoagulation, and a normal perfusion scan effectively excludes the diagnosis of PE. A normal/near normal scan interpretation also carries a sufficiently low prevalence of angiographically proven PE to withhold anticoagulation. Although the prevalence of PE in the setting of low probability scan interpretations is low and several outcomes studies have demonstrated a benign course in untreated patients with low probability scan results, patients with inadequate cardiopulmonary reserve do not necessarily have good outcomes. Such patients deserve more aggressive evaluation. Patients with intermediate probability scan results have a 20% to 40% prevalence of angiographically proven PE and thus require further investigation. The radionuclide investigation of DVT includes such techniques as radionuclide venography and thrombus-avid scintigraphy. Although these methods have not been as thoroughly evaluated as CU, studies thus far have indicated encouraging results, and further investigations are warranted. Pulmonary angiography has been the gold standard for the diagnosis of PE for decades. Studies have indicated that angiography has probably been underutilized by referring physicians for the evaluation of suspected PE, likely because of the perception of significant morbidity and mortality associated with the procedure. (ABSTRACT TRUNCATED)

Algorithms↗
PubMed1993

HLA matching: maximizing the number of compatible transplants.

1. Less than 10% of the cadaver kidneys currently allocated have 0-B,DR mismatches. 2. Up to 15% of the kidneys could be regionally allocated using the UNOS algorithm to 0-B,DR-mismatched recipients with a projected 67% 5-year graft survival. 3. Twice the number (32%) of recipients can be identified with zero of 10 A,B residues mismatched with the same 67% 5-year survival. 4. Another doubling (68%) of compatible recipients can be identified with zero of 7 DR supertypic determinants (4 DQ and 3 DRB) and zero of the A,B residues mismatched with a 66% 5-year graft survival. 5. Compressing A,B, and DR antigens to supertypic determinants reduces the racial differences in HLA to the point that 90% of kidneys can be allocated to Black recipients with zero of 3 DRB and zero A,B residues mismatched.

Black People↗
PubMed1995

An elastic compound tube model for a single osteon.

A model is developed whereby the secondary osteon--the dominant microstructural component of the cortical bone tissue--is considered as an n-layered cylinder with internal stresses in linear isotropic elasticity. An exact solution is obtained for a loading condition represented by a tensile-compressive force. The lengthening, the side deformation, and the strain energy of the system are explicitly calculated. The behavior of the main elastic quantities is illustrated by graphs. In particular, the important role played by the parity of the number of lamellae is revealed.

Algorithms↗
PubMed1995

Changes in proteoglycan synthesis of chondrocytes in articular cartilage are associated with the time-dependent changes in their mechanical environment.

Explant loading experiments were conducted to investigate the effect of load duration on proteoglycan synthesis. A compressive load of 0.1 MPa applied for 10 min was found to stimulate proteoglycan synthesis, while the same load applied for 20 h suppressed synthesis. This bimodal response suggests that the cells are responding to different mechanical stimuli as time progresses. A theoretical model has therefore been developed to describe the mechanical environment perceived by cells within soft hydrated tissues (e.g. articular cartilage) while the tissue is being loaded. The cells are modeled, using the biphasic theory, as fluid-solid inclusions embedded in and attached to a biphasic extracellular matrix of distinct material properties. A method of solution is developed which is valid for any axisymmetric loading configuration, provided that the cell radius, a, is small relative to the tissue height, h (i.e. h/a >> 1). A closed-form analytical solution for this inclusion problem is then presented for the confined compression configuration. Results from this model show that the mechanical environment in and around the cells is time dependent and inhomogeneous, and can be significantly influenced by differences in properties between the cell and the extracellular matrix.

Algorithms↗