Search results for " Enhancement"
showing 10 items of 521 documents
Experimentelle In-vitro-Studie zur Evaluierung eines elektronischen Detektors für die digitale Radiographie
2004
Purpose: To evaluate the contrast-detail performance of a flat-panel detector system, we performed a comparative study of this flat-panel system versus storage phosphor and conventional screen-film systems. Materials and Methods: Bone models made of human humeri were prepared with foreign bodies, fracture lines and drilled holes to create artificial fractures, osteolyses or metastases. Immersed in a water bath, hard copy images of these models were acquired with the same exposure dose (55 kV; 3.2 mAs) on the flat-panel detector, two state-of-the-art storage phosphor systems (PCR®, ADC®) and two conventional screen-film systems (Insight®, T-Mat®). Using a standardized protocol with a 4-point…
Advantages of fitting contrast curves using logistic function: a technical note.
2013
Objective The aim of this article is to demonstrate how the contrast properties of an imaging system can be ideally fitted with the use of stripe patterns and the logistic function. Study Design Stripe patterns with defined amounts of line pairs (lp/mm) per mm (10-20 lp/mm) were recorded with the use of digital photostimulable storage phosphor. Scan data and normalized image data were analyzed with the use of ImageJ and MatLab to calculate different contrast curves. Results For original scan data, the goodness of fit was 0.0000019 (sum of squared error [SSE]). The R-square was 0.9998. For normalized data the goodness of fit was 0.0007 (SSE) and the R-square 0.998. An amount of 50% contrast …
Quality management in higher education: A comparative study of the United Kingdom, the Netherlands and Finland
2010
This chapter examines lecturers’ perceptions of the balance between quality assurance and quality enhancement in three case study higher education institutions in different European countries. Where quality initiatives emphasised assurance rather than enhancement, this was taken to indicate a significant limitation on a lecturer’s autonomy in the quality management process. In-depth interviews using a semi-structured schedule were conducted with 20 randomly selected academic staff in each of the three higher education institutions. The results from the interviews demonstrated a very wide range of views among the interviewees. However, generally, it was found that there was a high level of d…
Myocardial fibrosis by delayed enhancement cardiovascular magnetic resonance and HCV infection in thalassemia major patients
2010
ss Open Acce Oral presentation Myocardial fibrosis by delayed enhancement cardiovascular magnetic resonance and HCV infection in thalassemia major patients Alessia Pepe1, Antonella Meloni1, Zelia Borsellino2, Maria Chiara Dell'Amico1, Vincenzo Positano1, Caterina Borgna-Pignatti3, Aurelio Maggio4, Gennaro Restaino5, Francesco Gagliardotto2, Paolo Cianciulli6, Luciano Prossomariti7, Aldo Filosa7, Michele Centra8, Domenico D'Ascola9, Antonella Quarta10, Angelo Peluso11, Antonello Pietrangelo12, Eliana Cracolici13, Massimo Lombardi*1 and Marcello Capra2
Low RNA translation activity limits the efficacy of hydrodynamic gene transfer to pig liver “in vivo”
2014
Background Hydrodynamic gene delivery has proved an efficient strategy for nonviral gene therapy in the murine liver but it has been less efficient in pigs. The reason for such inefficiency remains unclear. The present study used a surgical strategy to seal the whole pig liver in vivo. Methods A solution of enhanced green fluorescent protein (eGFP) DNA was injected under two different venous injection conditions (anterograde and retrograde), employing flow rates of 10 and 20 ml/s in each case, with the aim of identifying the best gene transfer conditions. The gene delivery and information decoding steps were evaluated by measuring the eGFP DNA, mRNA and protein copy number 24 h after transf…
Reduction of spherical-aberration impact in microscopy by wavefront coding
2009
In modern high-NA optical scanning instruments, like scanning microscopes, the refractive-index mismatch between the sample and the immersion medium introduces a significant amount of spherical aberration when imaging deep inside the specimen, spreading out the impulse response. Since such aberration depends on the focalization depth, it is not possible to achieve a static global compensation for the whole 3D sample in scanning microscopy. Therefore a depth-variant impulse response is generated. Consequently, the design of pupil elements that increase the tolerance to this aberration is of great interest. In this paper we report a hybrid technique that provides a focal spot that remains alm…
Image enhancement in simple fingerprint minutiae extraction algorithm using crossing number on valley structure
2007
In fingerprint recognition system, fingerprint feature extraction algorithm requires good quality fingerprint images to produce good results. Therefore, one step in the preprocessing stage is image enhancement to improve the quality of poor fingerprint image, so the minutiae points can be detected with good results. In this paper, we present how this enhancement process in simple minutiae detection algorithm using crossing number on valley structure improves detection of true minutiae.
Granulocyte–Colony Stimulating Factor plus Plerixafor in Patients with β-thalassemia Major Results in the Effective Mobilization of Primitive CD34+ C…
2017
Successful gene therapy for β-thalassemia requires optimal numbers of autologous gene-transduced hematopoietic stem and progenitor cells (HSPCs) with high repopulating capacity. Previous studies suggested superior mobilization in these patients by the combination of granulocyte–colony stimulating factor (G-CSF) plus plerixafor over single agents. We mobilized four adult patients using G-CSF+plerixafor to assess the intra-individual variation of the circulating CD34+ cells number and subtypes preand post-plerixafor administration. The procedure was well-tolerated and the target cell dose of ≥8×10 6 CD34+ cells/kg was achieved in three of them with one apheresis procedure. The addition of ple…
A surgical model for isolating the pig liver in vivo for gene therapy.
2013
Several studies report results that suggest the need of vascularization blocking for efficient gene transfer to the liver, especially in nonviral gene therapy. In this study, we describe a surgical strategy for in vivo isolation of the pig liver, resulting in a vascular watertight organ that allows the evaluation of several gene injection conditions. The hepatic artery and portal, suprahepatic and infrahepatic cava veins were dissected. Then, liver vascularization was excluded for 5-7 min. In that time, we first injected 200 ml saline solution containing the p3c-eGFP plasmid (20 µg/ml) simultaneously through two different catheters placed in the portal and cava veins, respectively. Vital co…
Boolean operations mediated by an ion-pair receptor of a multi-readout molecular logic gate
2013
A heteroditopic BODIPY dye that performs all basic Boolean operations with a cation (K+) and an anion (F-) as inputs and absorption, transmission and fluorescence as outputs is described. The molecular logic gate can also act as a digital comparator between the inputs.