Refine
Year of publication
Institute
- Fachbereich Medizintechnik und Technomathematik (520) (remove)
Language
- English (520) (remove)
Document Type
- Article (382)
- Conference Proceeding (95)
- Part of a Book (22)
- Book (9)
- Doctoral Thesis (3)
- Other (3)
- Patent (3)
- Lecture (2)
- Talk (1)
Keywords
- Finite-Elemente-Methode (12)
- Einspielen <Werkstoff> (10)
- FEM (6)
- Limit analysis (6)
- Shakedown analysis (6)
- shakedown analysis (6)
- Clusterion (5)
- Air purification (4)
- Hämoglobin (4)
- Lipopolysaccharide (4)
- Luftreiniger (4)
- Plasmacluster ion technology (4)
- Raumluft (4)
- limit analysis (4)
- CellDrum (3)
- Einspielanalyse (3)
- Kohlenstofffaser (3)
- Shakedown (3)
- Sonde (3)
- Technische Mechanik (3)
- Traglastanalyse (3)
- lipopolysaccharides (3)
- shakedown (3)
- Analytischer Zulaessigkeitsnachweis (2)
- Biocomposites (2)
- Bruchmechanik (2)
- Einspiel-Analyse (2)
- Eisschicht (2)
- Erythrozyt (2)
- Fibroblast (2)
- Iterative learning control (2)
- Natural fibres (2)
- Pflanzenphysiologie (2)
- Pflanzenscanner (2)
- Polymer-matrix composites (2)
- Stickstoffmonoxid (2)
- Stiffness (2)
- Stress concentrations (2)
- Traglast (2)
- biopotential electrodes (2)
- carbonized rice husk (2)
- celldrum technology (2)
- damage (2)
- limit load (2)
- locomotion (2)
- muscle fascicle behavior (2)
- nanostructured carbonized plant parts (2)
- nanostrukturierte carbonisierte Pflanzenteile (2)
- nitric oxide gas (2)
- plant scanner (2)
- ratchetting (2)
- ultrasound (2)
- ultrasound imaging (2)
- Achilles tendon (1)
- Adaptive control (1)
- Adsorption (1)
- Ageing (1)
- AlterG (1)
- Alternating plasticity (1)
- Alzheimer's disease (1)
- Analysis (1)
- Anastomose (1)
- Anastomosis (1)
- Anastomotic leakage (1)
- Anatomy (1)
- Annulus Fibrosus (1)
- Architectural gear ratio (1)
- Assistive technology (1)
- Autofluoreszenzverfahren (1)
- Autolysis (1)
- Automatic control (1)
- Axialbelastung (1)
- Axially cracked pipe (1)
- Bacillus sp (1)
- Bacterial cellulose (1)
- Bakterien (1)
- Basis Reduktion (1)
- Basis reduction (1)
- Bicharakteristikenverfahren (1)
- Biomechanical simulation (1)
- Biomechanics (1)
- Biomechanik (1)
- Biomedizinische Technik (1)
- Bioreaktor (1)
- Biosolubilization (1)
- Bladder (1)
- Blutzellenlagerung (1)
- Bone quality and biomechanics (1)
- Bone sawing (1)
- Carbon sources (1)
- Cardiac myocytes (1)
- Cardiac tissue (1)
- Cell permeability (1)
- Cellular force (1)
- Cellulose nanostructure (1)
- Cement infiltration (1)
- Cementoblast (1)
- Chance constrained programming (1)
- Circular Dichroism (1)
- Coefficient of ocular rigidity (1)
- Compression (1)
- Computational biomechanics (1)
- Constitutive model (1)
- Contractile tension (1)
- Convex optimization (1)
- Corneo-scleral shell (1)
- Cost-effectiveness (1)
- Culture media (1)
- Damage mechanics theory (1)
- Dattel (1)
- Decomposition (1)
- Deformation (1)
- Dekontamination (1)
- Design-by-analysis (1)
- Differential tonometry (1)
- Disc Degeneration (1)
- Discontinuous fractures (1)
- Druckbeanspruchung (1)
- Druckbehälter (1)
- Druckbelastung (1)
- Druckgeräte (1)
- Drug simulation (1)
- Dry surfaces (1)
- EEG (1)
- ELISA (1)
- ES-FEM (1)
- Einspiel-Kriterium (1)
- Einspielen (1)
- Elastizität (1)
- Elastodynamik (1)
- Elastostatics (1)
- Electromechanical modeling (1)
- Elektrodynamik (1)
- End-to-end colorectal anastomosis (1)
- Endothelial cells (1)
- Endothelial dysfunction (1)
- Endothelzelle (1)
- Environmental impact (1)
- Enzyme-linked immunosorbent assay (1)
- Epithel (1)
- Evolution of damage (1)
- Exact Ilyushin yield surface (1)
- Experiment (1)
- Extension fracture (1)
- Extension strain criterion (1)
- External knee adduction moments (1)
- Eyeball (1)
- FGF23 (1)
- FS-FEM (1)
- Fehlerstellen (1)
- Festkörper (1)
- Finite element analysis (1)
- Finite element analysis (FEA) (1)
- Finite element method (1)
- Finite element modelling (1)
- First Order Reliabiblity Method (1)
- First-order reliability method (1)
- Fließgrenze (1)
- Force (1)
- Forces (1)
- Fracture configuration (1)
- Fracture simulation (1)
- Freeze–thaw process (1)
- Frequency adaption (1)
- Geriatric (1)
- Glaucoma (1)
- Global and local collapse (1)
- Grenzwertberechnung (1)
- Growth modelling (1)
- Haemodialysis (1)
- Handbike (1)
- Harnleiter (1)
- Heart tissue culture (1)
- Hemoglobin structure (1)
- Hip fractures (1)
- Hodgkin–Huxley models (1)
- Homogenization (1)
- Human-Computer interaction (1)
- Hydrodynamik (1)
- Hydrogel (1)
- Hämoglobinstruktur (1)
- Impedance Spectroscopy (1)
- Induced pluripotent stem cells (1)
- Inotropic compounds (1)
- Intervertebral Disc (1)
- Intradiscal Pressure (1)
- Inverse dynamic problem (1)
- Inverse kinematic problem (1)
- Ion channels (1)
- Kinematics (1)
- Kinetics (1)
- Klotho (1)
- Knee (1)
- Knochen (1)
- Knochenbildung (1)
- Knochenchirugie (1)
- Knochendichte (1)
- Körpertemperatur (1)
- LPS (1)
- Lichtstreuungsbasierte Instrumente (1)
- Liver (1)
- Load modeling (1)
- Long COVID (1)
- Machine learning (1)
- Manipulated variables (1)
- Materialermüdung (1)
- Mechanical simulation (1)
- Mechanics (1)
- Mechanische Beanspruchung (1)
- Mechanotransduction (1)
- Medusomyces gisevi (1)
- Microbial adhesion (1)
- Microcirculation (1)
- Mild cognitive impairment (1)
- Mohr–Coulomb criterion (1)
- Multi-dimensional wave propagation (1)
- Multimode failure (1)
- Muscle (1)
- Muscle Fascicle (1)
- Muscle Force (1)
- Muscle fibers (1)
- Musculoskeletal model (1)
- Musculoskeletal system (1)
- Myocardial infarction and cardiac death (1)
- NONOate (1)
- Natriumhypochlorit (1)
- Niacin (1)
- Nichtlineare Gleichung (1)
- Nichtlineare Optimierung (1)
- Nichtlineare Welle (1)
- Nitric Oxide (1)
- Nitric Oxide Donor (1)
- Non-linear optimization (1)
- Non-parallel fissures (1)
- Nucleus Pulposus (1)
- Ocular blood flow (1)
- Organkultur (1)
- Osteoporose (1)
- Osteoporosis (1)
- PFM (1)
- PTH (1)
- Paralympic sport (1)
- Passive stretching (1)
- Pelvic floor dysfunction (1)
- Pelvic muscle (1)
- Permeability (1)
- Permeabilität (1)
- Peroxidase (1)
- Pflanzenstress (1)
- Pharmacology (1)
- Phosphate (1)
- Physiology (1)
- Plastizität (1)
- Post-COVID-19 syndrome (1)
- Pressure loaded crack-face (1)
- Pressure-volume relationship (1)
- Prevention (1)
- Progressive plastic deformation (1)
- Prophylaxis (1)
- Proteine (1)
- Proximal humerus fracture (1)
- Pulsations (1)
- RVA (1)
- Random variable (1)
- Ratcheting (1)
- Ratchetting (1)
- Recombinant activated protein C (1)
- Reconstruction (1)
- Red blood cell storage (1)
- Rehabilitation Technology and Prosthetics (1)
- Rehabilitation engineering (1)
- Reliability analysis (1)
- Reliability of structures (1)
- Retinal vessel analysis (1)
- Retinal vessels (1)
- Riboflavin (1)
- Robotic rehabilitation (1)
- Rohr (1)
- Rohrbruch (1)
- Rotator cuff (1)
- Running (1)
- S-FEM (1)
- Sampling methods (1)
- Schwammknochen (1)
- Sensitivity (1)
- Sepsis (1)
- Septic cardiomyopathy (1)
- Shakedown criterion (1)
- Simulation (1)
- Skeletal muscle (1)
- Sleep EEG (1)
- Small Aral Sea (1)
- Spleen (1)
- Stahl (1)
- Statics (1)
- Stochastic programming (1)
- Strukturanalyse (1)
- Surface microorganisms (1)
- Surgical Navigation and Robotics (1)
- Surgical staplers (1)
- Swabbing (1)
- Temperaturabhängigkeit (1)
- Tendon Rupture (1)
- Tendon properties (1)
- Tendons (1)
- Tension (1)
- Thiamine (1)
- Tissue Engineering (1)
- Training (1)
- Ultrasound (1)
- Uniaxial compression test (1)
- Ureter (1)
- Variable height stapler design (1)
- Vascular response (1)
- Vasomotions (1)
- Vertebroplastie (1)
- Vertebroplasty (1)
- Viscous flow (1)
- Viskose Strömung (1)
- Viskosität (1)
- Visual field asymmetry (1)
- Vitamin A (1)
- Vitamin B (1)
- Vitamin D (1)
- Wasserbrücke (1)
- Wasserstoffperoxid (1)
- Wellen (1)
- Wolff's Law (1)
- Wolffsches Gesetz (1)
- Wundheilung (1)
- Zug-Druck Belastung (1)
- achilles tendon (1)
- actin cytoskeleton (1)
- activated nanostructured carbon (1)
- adipose-derived stromal cells (ASCs) (1)
- adsorption (1)
- agility (1)
- aktivierte nanostrukturierte Kohlenstofffaser (1)
- alternierend Verformbarkeit (1)
- anaesthetic complications (1)
- anisotropy (1)
- aortic perfusion (1)
- aromatic amines (1)
- autofluorescence-based detection system (1)
- biaxial tensile experiment (1)
- bicharacteristics (1)
- biomechanics (1)
- bone density (1)
- bone structure (1)
- burst pressure (1)
- burst tests (1)
- cancellous bone (1)
- cardiomyocyte biomechanics (1)
- cell aerosolization (1)
- cell atomization (1)
- cerebral small vessel disease (1)
- chance constrained programming (1)
- cognitive impairment (1)
- community dwelling (1)
- computational fluid dynamics analysis (1)
- connective tissue (1)
- constitutive modeling (1)
- constructive alignment (1)
- contractile tension (1)
- correlation (1)
- cytosolic water diffusion (1)
- date palm tree (1)
- dental trauma (1)
- design-by-analysis (1)
- dialysis (1)
- difficult airway (1)
- direct method (1)
- distorted element (1)
- double-lumen tube intubation (1)
- drop jump (1)
- ecological structure (1)
- elastic solids (1)
- electromyography (1)
- endoluminal (1)
- energy absorption (1)
- energy dissipation (1)
- epithelization (1)
- examination (1)
- extracorporeal membrane oxygenation (1)
- fatigue analyses (1)
- finite element analysis (1)
- flaw (1)
- force generation (1)
- forehead EEG (1)
- fortschreitende plastische Deformation (1)
- gait (1)
- healthy aging (1)
- hemoglobin (1)
- hemoglobin dynamics (1)
- hiPS cardiomyocytes (1)
- high-intensity exercise (1)
- human dermal fibroblasts (1)
- humic acid (1)
- hydrogel (1)
- hyper-gravity (1)
- hyperelastic (1)
- hypo-gravity (1)
- impedance spectroscopy (1)
- in-ear EEG (1)
- intraclass correlation coefficient (1)
- kontraktile Spannung (1)
- konvexe Optimierung (1)
- light scattering analysis (1)
- lignite (1)
- limit and shakedown analysis (1)
- linear kinematic hardening (1)
- lipopolysaccharide (1)
- load limit (1)
- long-term retention (1)
- lower bound theorem (1)
- material shakedown (1)
- mechanical buffer (1)
- mechanical waves (1)
- metagenomics (1)
- microbial diversity (1)
- multimodal (1)
- muscle mechanics (1)
- naphtols (1)
- non-simplex S-FEM elements (1)
- nonlinear kinematic hardening (1)
- nonlinear optimization (1)
- nonlinear solids (1)
- nonlinear tensor constitutive equation (1)
- overload (1)
- parabolic flight (1)
- performance testing (1)
- phenols (1)
- physiology (1)
- pipes (1)
- plant stress (1)
- plasma generated ions (1)
- practical learning (1)
- prevention (1)
- probabilistic fracture mechanics (1)
- protein (1)
- psychosocial (1)
- rehabilitation (1)
- reliability (1)
- reliability analysis (1)
- reliability of structures (1)
- retinal microvasculature (1)
- retinal vessels (1)
- rhAPC (1)
- running (1)
- sEMG (1)
- sarcomere operating length (1)
- second-order reliability method (1)
- sensors (1)
- series elastic element behavior (1)
- shakedown analyses (1)
- shotgun sequencing (1)
- shoulder (1)
- simulation (1)
- smooth muscle contraction (1)
- sprint start (1)
- standard error of measurement (1)
- stiffness (1)
- stochastic programming (1)
- strain energy function (1)
- stretch reflex (1)
- stretch-shortening cycle (1)
- subsurface ice research (1)
- subsurface probe (1)
- surface modification (1)
- survival (1)
- tendon rupture (1)
- tension–torsion loading (1)
- test-retest reliability (1)
- thermal ratcheting (1)
- training simulator (1)
- tri-lineage differentiation (1)
- twin-fluid atomizer (1)
- ultrasonography (1)
- unloading (1)
- vessels (1)
- videolaryngoscopy (1)
- virgin passive (1)
- virtual reality (1)
- viscoelasticity (1)
- walking (1)
- walking gait (1)
- water bridge phenomenon (1)
- wound healing (1)
- yield stress (1)
The term ocular rigidity is widely used in clinical ophthalmology. Generally it is assumed as a resistance of the whole eyeball to mechanical deformation and relates to biomechanical properties of the eye and its tissues. Basic principles and formulas for clinical tonometry, tonography and pulsatile ocular blood flow measurements are based on the concept of ocular rigidity. There is evidence for altered ocular rigidity in aging, in several eye diseases and after eye surgery. Unfortunately, there is no consensual view on ocular rigidity: it used to make a quite different sense for different people but still the same name. Foremost there is no clear consent between biomechanical engineers and ophthalmologists on the concept. Moreover ocular rigidity is occasionally characterized using various parameters with their different physical dimensions. In contrast to engineering approach, clinical approach to ocular rigidity claims to characterize the total mechanical response of the eyeball to its deformation without any detailed considerations on eye morphology or material properties of its tissues. Further to the previous chapter this section aims to describe clinical approach to ocular rigidity from the perspective of an engineer in an attempt to straighten out this concept, to show its advantages, disadvantages and various applications.
The paper presents a method for the quantitative assessment of choroidal blood flow using an OCT-A system. The developed technique for processing of OCT-A scans is divided into two stages. At the first stage, the identification of the boundaries in the selected portion was performed. At the second stage, each pixel mark on the selected layer was represented as a volume unit, a voxel, which characterizes the region of moving blood. Three geometric shapes were considered to represent the voxel. On the example of one OCT-A scan, this work presents a quantitative assessment of the blood flow index. A possible modification of two-stage algorithm based on voxel scan processing is presented.
Dynamic retinal vessel analysis (DVA) provides a non-invasive way to assess microvascular function in patients and potentially to improve predictions of individual cardiovascular (CV) risk. The aim of our study was to use untargeted machine learning on DVA in order to improve CV mortality prediction and identify corresponding response alterations.
Retinal endothelial function in cardiovascular risk patients: A randomized controlled exercise trial
(2020)
The aim of this study was to investigate, for the first time, the effects of high-intensity interval training (HIIT) on retinal microvascular endothelial function in cardiovascular (CV) risk patients. In the randomized controlled trial, middle-aged and previously sedentary patients with increased CV risk (aged 58 ± 6 years) with ≥ two CV risk factors were randomized into a 12-week HIIT (n = 33) or control group (CG, n = 36) with standard physical activity recommendations. A blinded examiner measured retinal endothelial function by flicker light-induced maximal arteriolar (ADmax) and venular (VDmax) dilatation as well as the area under the arteriolar (AFarea) and venular (VFarea) flicker curve using a retinal vessel analyzer. Standardized assessments of CV risk factors, cardiorespiratory fitness, and retinal endothelial function were performed before and after HIIT. HIIT reduced body mass index, fat mass, and low-density lipoprotein and increased muscle mass and peak oxygen uptake (VO2peak). Both ADmax (pre: 2.7 ± 2.1%, post: 3.0 ± 2.2%, P = .018) and AFarea (pre: 32.6 ± 28.4%*s, post: 37.7 ± 30.6%*s, P = .016) increased after HIIT compared with CG (ADmax, pre: 3.2 ± 1.8%, post: 2.9 ± 1.8%, P = .254; AFarea, pre: 41.6 ± 28.5%*s, post: 37.8 ± 27.0%*s, P = .186). Venular function remained unchanged after HIIT. There was a significant association between ∆-change VO2peak and ∆-changes ADmax and AFarea (P = .026, R² = 0.073; P = .019, R² = 0.081, respectively). 12-weeks of HIIT improved retinal endothelial function in middle-aged patients with increased CV risk independent of the reduction in classical CV risk factors. Exercise has the potential to reverse or at least postpone progression of small vessel disease in older adults with increased CV risk under standard medication. Dynamic retinal vessel analysis seems to be a sensitive tool to detect treatment effects of exercise interventions on retinal microvascular endothelial function in middle-aged individuals with increased CV risk.
Background
For supratentorial craniotomy, surgical access, and closure technique, including placement of subgaleal drains, may vary considerably. The influence of surgical nuances on postoperative complications such as cerebrospinal fluid leakage or impaired wound healing overall remains largely unclear. With this study, we are reporting our experiences and the impact of our clinical routines on outcome in a prospectively collected data set.
Method
We prospectively observed 150 consecutive patients undergoing supratentorial craniotomy and recorded technical variables (type/length of incision, size of craniotomy, technique of dural and skin closure, type of dressing, and placement of subgaleal drains). Outcome variables (subgaleal hematoma/CSF collection, periorbital edema, impairment of wound healing, infection, and need for operative revision) were recorded at time of discharge and at late follow-up.
Results
Early subgaleal fluid collection was observed in 36.7% (2.8% at the late follow-up), and impaired wound healing was recorded in 3.3% of all cases, with an overall need for operative revision of 6.7%. Neither usage of dural sealants, lack of watertight dural closure, and presence of subgaleal drains, nor type of skin closure or dressing influenced outcome. Curved incisions, larger craniotomy, and tumor size, however, were associated with an increase in early CSF or hematoma collection (p < 0.0001, p = 0.001, p < 0.01 resp.), and larger craniotomy size was associated with longer persistence of subgaleal fluid collections (p < 0.05).
Conclusions
Based on our setting, individual surgical nuances such as the type of dural closure and the use of subgaleal drains resulted in a comparable complication rate and outcome. Subgaleal fluid collections were frequently observed after supratentorial procedures, irrespective of the closing technique employed, and resolve spontaneously in the majority of cases without significant sequelae. Our results are limited due to the observational nature in our single-center study and need to be validated by supportive prospective randomized design.
Masked hypertension is known to induce microvascular complications. However, it is unclear whether early microvascular changes are already occurring in young, otherwise healthy adults. We therefore investigated whether retinal microvascular calibers and acute responses to a flicker stimulus are related to masked hypertension. We used the baseline data of 889 participants aged 20–30 years who were taking part in the African Prospective study on the Early Detection and Identification of Cardiovascular Disease and Hypertension. Clinic and 24-h ambulatory blood pressure were measured. The central retinal artery equivalent (CRAE) and central retinal vein equivalent were calculated from fundus images, and retinal vessel dilation was determined in response to flicker light-induced provocation. A smaller CRAE was observed in those with masked hypertension vs. those with normotension (157.1 vs. 161.2 measuring units, P < 0.001). In forward multivariable-adjusted regression analysis, only CRAE was negatively related to masked hypertension [adjusted R² = 0.267, β = −0.097 (95% CI = −0.165; −0.029), P = 0.005], but other retinal microvascular parameters were not associated with masked hypertension. In multivariable logistic regression analyses, masked hypertension [OR = 2.333, (95% CI = 1.316; 4.241), P = 0.004] was associated with a narrower CRAE. In young healthy adults, masked hypertension was associated with retinal arteriolar narrowing, thereby reflecting early microvascular alterations known to predict cardiovascular outcomes in later life.
Clearance of blood components and fluid drainage play a crucial role in subarachnoid hemorrhage (SAH) and post hemorrhagic hydrocephalus (PHH). With the involvement of interstitial fluid (ISF) and cerebrospinal fluid (CSF), two pathways for the clearance of fluid and solutes in the brain are proposed. Starting at the level of capillaries, flow of ISF follows along the basement membranes in the walls of cerebral arteries out of the parenchyma to drain into the lymphatics and CSF [1]–[3]. Conversely, it is shown that CSF enters the parenchyma between glial and pial basement membranes of penetrating arteries [4]–[6]. Nevertheless, the involved structures and the contribution of either flow pathway to fluid balance between the subarachnoid space and interstitial space remains controversial. Low frequency oscillations in vascular tone are referred to as vasomotion and corresponding vasomotion waves are modeled as the driving force for flow of ISF out of the parenchyma [7]. Retinal vessel analysis (RVA) allows non-invasive measurement of retinal vessel vasomotion with respect to diameter changes [8]. Thus, the aim of the study is to investigate vasomotion in RVA signals of SAH and PHH patients.