Search results for "Biomedical engineering"

Development of a Multifunctional Bioerodible Nanocomposite Containing Metronidazole and Curcumin to Apply on L-PRF Clot to Promote Tissue Regeneratio…

2020

Teeth extractions are often followed by alveolar bone reabsorption, although an adequate level of bone is required for reliable rehabilitations by dental implants. Leukocyte and platelet-rich fibrin (L-PRF) has been widely applied in regenerative procedures and with antibiotic and antioxidant agents could play an essential role in hard and soft tissue healing. In this work, a nanocomposite (Sponge-C-MTR) consisting of a hyaluronate-based sponge loaded with metronidazole (MTR) and nanostructured lipid carriers containing curcumin (CUR-NLC) was designed to be wrapped in the L-PRF&trade

2018

Electrocardiographic imaging (ECGI) strongly relies on a priori assumptions and additional information to overcome ill-posedness. The major challenge of obtaining good reconstructions consists in finding ways to add information that effectively restricts the solution space without violating properties of the sought solution. In this work, we attempt to address this problem by constructing a spatio-temporal basis of body surface potentials (BSP) from simulations of many focal excitations. Measured BSPs are projected onto this basis and reconstructions are expressed as linear combinations of corresponding transmembrane voltage (TMV) basis vectors. The novel method was applied to simulations o…

A Method to Extract the Complete Fiber Network Topology of Planar Fibrous Tissues and Scaffolds

2010

Improving fabrication protocols and design strategies, investigating on how fibrous ECM and synthetic architectures affect cell morphology, metabolism and phenotypic expression, predicting mechanical behaviors, have increasingly become crucial goals in the understanding of native tissues and in the development of engineered tissue. In the present study, an image-based analysis approach that provides an automatic tool to fully characterize engineered tissue fiber network topology was developed. The following micro architectural features were detected: fiber angle distribution, fiber connectivity, fiber overlap spatial density, and fiber diameter. In order to demonstrate the potential of this…

P1450Effect of overweight and obesity on left ventricular longitudinal multi-layer strain: a speckle tracking two-dimensional echocardiographic study

2017

Assessment of image quality of intracoronary ultrasound systems with tissue-equivalent vessel phantoms

2002

Imaging of vascular structures by intracoronary ultrasound (ICUS) is finding more and more applications in coronary diagnosis and in the assessment of interventional access. The authors describe a method for easy and quick production of tissue-equivalent vessel phantoms from a special hydrocolloid. The mechanical tolerance is less than 3/100 mm. With these phantoms the authors tested the calibration and measured the resolution properties of the SONOS intravascular ultrasonic system (Hewlett Packard). The measurements revealed a slight space related underestimation of diameters up to 280 /spl mu/m. Using cross correlation and auto correlation functions the authors analyzed digitized ultrason…

A scoping review on the use of speech-to-text technology for adolescents with learning difficulties in secondary education

2022

To identify and describe the aims, methodological approaches, and major findings of studies on the use of STT among secondary pupils (age 12-18) with learning difficulties published from January 2000 to April 2022.This scoping review includes empirical studies published in peer-reviewed journals and grey literature between January 2000 and April 2022. Searches were conducted in April 2022 in three databases: ERIC, PsycINFO and Scopus. In addition, related reviews were manually screened for relevant papers.Eight peer-revied studies and five publications of grey literature were found to meet the inclusion criteria; two studies employed experimental designs, four employed quasi-experimental de…

Combining split-and-merge and multi-seed region growing algorithms for uterine fibroid segmentation in MRgFUS treatments

2016

Uterine fibroids are benign tumors that can affect female patients during reproductive years. Magnetic resonance-guided focused ultrasound (MRgFUS) represents a noninvasive approach that uses thermal ablation principles to treat symptomatic fibroids. During traditional treatment planning, uterus, fibroids, and surrounding organs at risk must be manually marked on MR images by an operator. After treatment, an operator must segment, again manually, treated areas to evaluate the non-perfused volume (NPV) inside the fibroids. Both pre- and post-treatment procedures are time-consuming and operator-dependent. This paper presents a novel method, based on an advanced direct region detection model, …

Novel photoreception system in sponges?

2006

Abstract Sponges (phylum Porifera) of the classes Hexactinellida and Demospongiae possess a skeleton composed of siliceous spicules, which are synthesized enzymatically. The longest spicules are found among the Hexactinellida, with the stalk spicules (length: 30 cm; diameter: 300 μm) of Hyalonema sieboldi as prominent examples. These spicules are constructed around a central axial filament, which is formed by approximately 40 siliceous layers. The stratified spicules function as optical glass fibers with unique properties. If free-spaced coupled with a white light source (WLS), the entire fiber is illuminated. Special features of the light transmission: (i) only wavelengths between 615 and …

Comparison of magnetic resonance imaging of inhaled SF6 with respiratory gas analysis

2008

Magnetic resonance imaging of inhaled fluorinated inert gases ((19)F-MRI) such as sulfur hexafluoride (SF(6)) allows for analysis of ventilated air spaces. In this study, the possibility of using this technique to image lung function was assessed. For this, (19)F-MRI of inhaled SF(6) was compared with respiratory gas analysis, which is a global but reliable measure of alveolar gas fraction. Five anesthetized pigs underwent multiple-breath wash-in procedures with a gas mixture of 70% SF(6) and 30% oxygen. Two-dimensional (19)F-MRI and end-expiratory gas fraction analysis were performed after 4 to 24 inhaled breaths. Signal intensity of (19)F-MRI and end-expiratory SF(6) fraction were evaluat…

Accuracy and stability of temperature probes for intracranial application.

2004

Intracranial temperature measurement may play a pivotal role for prognosis and treatment of neurological and neurosurgical patients. For reliable clinical application, accurate temperature readings are therefore necessary. We present an independent in vitro study investigating the accuracy and stability of three temperature probes. Eight Neurovent-P Temp (RN), eight Licox temperature sensors (LT) and eight Neurotrend sensors (NT) were placed into a water bath. The temperature was increased in 3 degrees C increments from 30 to 42 degrees C before (accuracy test day 0) and after (accuracy test day 5) a long-term stability test run at 37 +/- 0.2 degrees C. The accuracy tests revealed deviation…