Search results for "Magnification"
showing 10 items of 88 documents
Biomagnification of organohalogens in Atlantic salmon (Salmo salar) from its main prey species in three areas of the Baltic Sea
2012
Abstract Factors affecting the biomagnification of organohalogens in Baltic salmon from sprat, herring and three-spined stickleback were assessed in three feeding areas. Second sea-year salmon contained (in fresh weight of whole fish) 79–250 ng g− 1 polychlorinated biphenyls (ΣPCB), 0.9–2.7 pg g− 1 dibenzo-p-dioxins (ΣPCDD), 8–19 pg g− 1 dibenzofurans (ΣPCDF), 96–246 pg g− 1 coplanar PCBs, 2.4–3.6 ng g− 1 polybrominated diphenylethers (ΣPBDE), and 39–136 ng g− 1 Σindicator PCB6. The EU limits for WHO toxic equivalent concentrations in fish feed were already exceeded in one-year-old sprat and herring and were exceeded many-fold in older age groups. The differences in the biomagnification rat…
Accurate single-shot quantitative phase imaging of biological specimens with telecentric digital holographic microscopy
2014
The advantages of using a telecentric imaging system in digital holographic microscopy (DHM) to study biological specimens are highlighted. To this end, the performances of nontelecentric DHM and telecentric DHM are evaluated from the quantitative phase imaging (QPI) point of view. The evaluated stability of the microscope allows single-shot QPI in DHM by using telecentric imaging systems. Quantitative phase maps of a section of the head of the drosophila melanogaster fly and of red blood cells are obtained via single-shot DHM with no numerical postprocessing. With these maps we show that the use of telecentric DHM provides larger field of view for a given magnification and permits more acc…
Review article: in vivo imaging by endocytoscopy
2011
Aliment Pharmacol Ther 2011; 33: 1183–1193 Summary Background Endocytoscopy (EC) enables in vivo microscopic imaging at 1400-fold magnification, thereby allowing the analysis of mucosal structures at the cellular level. In contrast to fluorescence imaging with confocal laser endomicroscopy which allows analysis of mucosal structures up to 250 μm in depth, EC is based on the principle of contact light microscopy and only allows visualisation of the very superficial mucosal layer. Aim To systematically review the feasibility and diagnostic yield of EC for in vivo diagnosis of diseases. Methods A systematic search of the literature on diagnostic interventions in the gastrointestinal tract u…
Perfluorinated Compounds’ Analysis, Environmental Fate and Occurrence: The Llobregat River as Case Study
2012
Perfluorinated compounds are industrial chemicals widely used for more than 60 years. However, during the last decade, due to their high resistance to degradation, bioaccumulation attached to proteins, biomagnification to the food chain and their relation to toxicological effects of these compounds have gained scientific and regulatory attention.
White Matter Relationships Examined by Transillumination Technique Using a Lateral Transcortical Parietal Approach to the Atrium: Three-Dimensional I…
2019
Background Numerous lesions are found in the ventricular atrium (VA). Access is gained through many white matter tracts with great relevance and specific neurologic functions. It is important to understand the configuration of the most relevant structures surrounding this zone and, thus, select the safest entry zone on the lateral cerebral surface. Objective We studied the white matter layers traversed in the lateral transcortical parietal approach through the intraparietal sulcus (IPS), adding a transillumination technique. With this knowledge, we selected the safest highway to improve this particular approach. Methods An in-depth study of the white matter tracts was performed on 24 cerebr…
Endoscopic assessment and grading of Barrett's esophagus using magnification endoscopy and narrow-band imaging: accuracy and interobserver agreement …
2010
Background: Three different classification systems for the evaluation of Barrett's esophagus (BE) using magnification endoscopy (ME) and narrow-band imaging (NBI) have been proposed. Until now, no comparative and external evaluation of these systems in a clinical-like situation has been performed. Objective: To compare and validate these 3 classification systems. Design: Prospective validation study. Setting: Tertiary-care referral center. Nine endoscopists with different levels of expertise from Europe and Japan participated as assessors. Patients: Thirty-two patients with long-segment BE. Interventions: From a group of 209 standardized prospective recordings collected on BE by using …
Chromoendoscopy and narrow-band imaging compared with high-resolution magnification endoscopy in Barrett's esophagus.
2008
Background & Aims: The aim of this study was to compare magnified still images obtained with high-resolution white light endoscopy, indigo carmine chromoendoscopy, acetic acid chromoendoscopy, and narrow-band imaging to determine the best technique for use in Barrett's esophagus. Methods: We obtained magnified images from 22 areas with the 4 aforementioned techniques. Seven endoscopists with no specific expertise in Barretes esophagus or advanced imaging techniques and 5 international experts in this field evaluated these 22 areas for overall image quality, mucosal image quality, and vascular image quality. In addition, the regularity of mucosal and vascular patterns and the presence of abn…
Clinical magnification and residual refraction after implantation of a double intraocular lens system in patients with macular degeneration
2007
Purpose To evaluate the efficacy of a standard double intraocular lens (IOL) system (IOL-Vip) in patients with low vision and central scotoma due to macular degeneration and assess the predictability of the residual refraction and magnification. Setting Ophthalmology Department, Hospital General Universitario, Valencia, Spain. Methods This interventional prospective noncomparative case series comprised 13 consecutive surgical procedures in 10 patients with central scotoma. Follow-up was 12 months. Evaluation included the difference between preoperative and postoperative best corrected visual acuity (BCVA), refraction, position of the IOLs, endothelial cell density, and occurrence of postope…
Fast Axial-Scanning Widefield Microscopy With Constant Magnification and Resolution
2015
In this paper, we propose the use of electrically-addressable lens devices for performing fast non-mechanical axial scanning when imaging three-dimensional samples. This non-mechanical method can be implemented in any commercial microscope. The approach is based on the insertion of the tunable lens at the aperture stop of the microscope objective. By tuning the voltage, a stack of depth images of 3D specimens can be captured in real time and with constant magnification and resolution. The main advantage of our technique is the possibility of performing fast axial scanning free of mechanical vibrations.
Variable magnification digital in-line holographic microscopy
2019
We present a new layout providing different magnifications and resolution capabilities in lensless imaging by using an electrically tunable lens (ETL). Experimental validation is reported using a resolution test target and prostate cancer cells.