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Technical Developments (technical + development)
Kinds of Technical Developments Selected AbstractsConventional MRI in Multiple SclerosisJOURNAL OF NEUROIMAGING, Issue 2007Massimo Filippi MD ABSTRACT During the past 10 years, conventional magnetic resonance imaging (cMRI) has become an established tool for the assessment of patients with multiple sclerosis (MS) and to monitor treatment trials. This is mainly due to the sensitivity and reproducibility of cMRI in the detection of MS-related damage. A large effort has also been devoted to develop imaging strategies capable of providing accurate estimates of the extent of disease-related damage not only in the brain, but also in the spinal cord and optic nerve. Guidelines have been defined to integrate MR findings in the diagnostic evaluation of patients at presentation with clinically isolated syndromes suggestive of MS, and specific acquisition protocols have been offered for monitoring longitudinal changes in patients with established disease. Despite the fact that the role of cMRI in MS has been profoundly obviated by the advent of modern and quantitative MR techniques, several issues are still unresolved. Technical development in acquisition and postprocessing, as well as the introduction of high-field magnets in the clinical arena, are likely to increase our understanding of disease pathobiology, mainly through an increased ability to quantify the extent of gray matter damage. [source] Modified Hadamard transform microchip electrophoresisELECTROPHORESIS, Issue 16 2005Renato Guchardi Abstract Sensitivity is a crucial point in the development applications for medicine or environmental samples in which the analytes are present in the nanomolar range. Besides further technical development of detection systems, the multiplex sample injection technique can be applied for enhancing the signal-to-noise ratio. Hadamard transform is easily applied to microchip electrophoresis due to the fact that sample injection is generally achieved through cross, double-tee, or tee injector structures. This paper reports the first demonstration of a modified Hadamard transform electrophoresis on a microchip by using an amperometric detector. Contrary to the previous Hadamard applications, the resolution (number of points per unit of time) of electropherograms obtained is independent of the number of injections. [source] Embedding 3D models of biological specimens in PDF publicationsMICROSCOPY RESEARCH AND TECHNIQUE, Issue 11 2008Bernhard Ruthensteiner Abstract By providing two examples, the option for embedding 3D models in electronic versions of life science publications is presented. These examples, presumably representing the first such models published, are developmental stages of an evertebrate (Patella caerulea, Mollusca) and a vertebrate species (Psetta maxima, Teleostei) obtained from histological section series reconstruction processed with the software package Amira. These surface rendering models are particularly suitable for a PDF file because they can easily be transformed to a file format required and components may be conveniently combined and hierarchically arranged. All methodological steps starting from specimen preparation until embedding of resulting models in PDF files with emphasis on conversion of Amira data to the appropriate 3D file format are explained. Usability of 3D models in PDF documents is exemplified and advantages over 2D illustrations are discussed, including better explanation capabilities for spatial arrangements, higher information contents, and limiting options for disguising results by authors. Possibilities for additional applications reaching far beyond the examples presented are suggested. Problems such as long-term compatibility of file format and hardware plus software, editing and embedding of files, file size and differences in information contents between printed and electronic version will likely be overcome by technical development and increasing tendency toward electronic at the cost of printed publications. Since 3D visualization plays an increasing role in manifold disciplines of science and appropriate tools for the popular PDF format are readily available, we propose routine application of this way of illustration in electronic life science papers. Microsc. Res. Tech., 2008. © 2008 Wiley-Liss, Inc. [source] A new type of magnification system in free microvascular tissue transfer: Varioscope M5MICROSURGERY, Issue 6 2007Ph.D., Stefano Chiummariello M.D. Free microvascular tissue transfers have become today a key instrument for the surgical treatment of wide loss of tissue. These procedures can provide definitive treatment in a single operation but they are expensive and require specialized practitioners. The operating microscope traditionally has provided this requirement; our study is focusing on the prospect of using a new visual system,Varioscope M5,in the reconstructive microsurgery field. Varioscope M5 (Life Optics, Vienna, Austria) has been employed in 21 microvascular anastomoses, where different free flaps were used in head and neck reconstruction. The necessity to operate in a different department, not provided with an operating microscope, brought along the idea of exploring an alternative procedure to classical visualization systems. Specific advantages such as reduced cost, freedom of movement, autofocus, minimal upkeep, a variable range of magnification from 2× to 9× are some of the reasons that convinced the authors to use this new type of magnification system. Increasing interest in microsurgery magnification highlights the need for further technical development in that field. We consider Varioscope M5 a future mean of anastomotic magnification in most free-tissue transfers with specific characteristics that combine the microscope and loupe philosophies. © 2007 Wiley-Liss, Inc. Microsurgery, 2007. [source] Technology preview: X-ray fused with magnetic resonance during invasive cardiovascular proceduresCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 6 2007Luis F. Gutiérrez PhD Abstract Background: We have developed and validated a system for real-time X-ray fused with magnetic resonance imaging, MRI (XFM), to guide catheter procedures with high spatial precision. Our implementation overlays roadmaps,MRI-derived soft-tissue features of interest,onto conventional X-ray fluoroscopy. We report our initial clinical experience applying XFM, using external fiducial markers, electrocardiogram (ECG)- gating, and automated real-time correction for gantry and table movement. Methods: This prospective case series for technical development was approved by the NHLBI Institutional Review Board and included 19 subjects. Multimodality external fiducial markers were affixed to patients' skin before MRI, which included contrast-enhanced, 3D T1-weighted, or breath-held and ECG-gated 2D steady state free precession imaging at 1.5T. MRI-derived roadmaps were manually segmented while patients were transferred to a calibrated X-ray fluoroscopy system. Image spaces were registered using the fiducial markers and thereafter permitted unrestricted gantry rotation, table panning, and magnification changes. Static and ECG-gated MRI data were transformed from 3D to 2D to correspond with gantry and table position and combined with live X-ray images. Results: Clinical procedures included graft coronary arteriography, right ventricular free-wall biopsy, and iliac and femoral artery recanalization and stenting. MRI roadmaps improved operator confidence, and in the biopsy cases, outperformed the best available alternative imaging modality. Registration errors were increased when external fiducial markers were affixed to more mobile skin positions, such as over the abdomen. Conclusion: XFM using external fiducial markers is feasible during X-ray guided catheter treatments. Multimodality image fusion may prove a useful adjunct to invasive cardiovascular procedures. © 2007 Wiley-Liss, Inc. [source] Role of Parasternal Data Acquisition During Contrast Enhanced Real-Time Three-Dimensional EchocardiographyECHOCARDIOGRAPHY, Issue 10 2007Attila Nemes M.D., Ph.D. Background: Recent technical developments have resulted in high-resolution real time three-dimensional echocardiography (RT3DE). The purpose of this study was to investigate the beneficial role of parasternal-acquired images in addition to apical-acquired images during contrast stress RT3DE. Methods: The study comprised 30 consecutive patients (52 ± 11 years, 18 males) with chest pain referred for routine stress testing. The contrast RT3DE images were acquired from the apical and parasternal window with a Sonos 7500 echo system attached to a X4 matrix array transducer. Results: From the apical and parasternal acquisition, 464 segments (91%) and 267 segments (52%) could be analyzed, respectively (P < 0.001). From the apical window, more basal segments were not analyzable (22 of 180, 12% vs. 24 of 330, 7%; P = 0.06). From the parasternal window, more apical segments were not analyzable (117 of 150, 78% vs. 126 of 360, 35%; P < 0.01). The mean image quality index of the 464 analyzable segments from the apical-acquired images was 2.43. Fourteen of 180 basal segments (8%), 12 of 180 midventricular segments (7%) and 2 of 150 apical segment (1%) were only available with parasternal data acquisition. In addition to these 28 segments, 79 segments (15%) already visualized from the apical window improved in quality. The overall mean image quality index, now assessed from 492 (96%) of all segments, using both the apical and parasternal acquired data, improved to 2.74 (P < 0.05). Conclusions: Addition of parasternal to apical acquisition of contrast RT3DE data can decrease the number of nonvisualized segments and improve mean image quality. [source] Evaluation of operators' performance for automation design in the fully digital control room of nuclear power plantsHUMAN FACTORS AND ERGONOMICS IN MANUFACTURING & SERVICE INDUSTRIES, Issue 1 2010Chiuhsiang Joe Lin Abstract Recent technical developments in computer hardware and software have meant that human,machine systems can be automated in many respects. If automation fails, however, human operators can have difficulty in recognizing the existence of a problem, identifying what has failed, and taking corrective action to remedy these out-of-the-loop (OOTL) performance problems. Several studies have suggested that taxonomies of levels of automation (LOAs) and types of automation (TOAs) can be used to solve OOTL problems. This study examined the impact of LOAs in process control automation within the context of nuclear power plants (NPPs). A simulation experiment in an NPP is performed to validate this framework using an automatic mode and a semiautomatic mode. Mental demand is found to be significantly reduced under the automatic mode; however, participants felt frustrated with this LOA. Situation awareness is found to be similar in the two modes. The results of an end-of-experiment subjective rating reveal that participants were evenly divided between the two modes with respect to generating and selecting functions. It is therefore suggested that human operators be involved in generating and selecting functions under an automatic mode. © 2009 Wiley Periodicals, Inc. [source] Analyzing cell fate control by cytokines through continuous single cell biochemistryJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 2 2009Michael A. Rieger Abstract Cytokines are important regulators of cell fates with high clinical and commercial relevance. However, despite decades of intense academic and industrial research, it proved surprisingly difficult to describe the biological functions of cytokines in a precise and comprehensive manner. The exact analysis of cytokine biology is complicated by the fact that individual cytokines control many different cell fates and activate a multitude of intracellular signaling pathways. Moreover, although activating different molecular programs, different cytokines can be redundant in their biological effects. In addition, cytokines with different biological effects can activate overlapping signaling pathways. This prospect article will outline the necessity of continuous single cell biochemistry to unravel the biological functions of molecular cytokine signaling. It focuses on potentials and limitations of recent technical developments in fluorescent time-lapse imaging and single cell tracking allowing constant long-term observation of molecules and behavior of single cells. J. Cell. Biochem. 108: 343,352, 2009. © 2009 Wiley-Liss, Inc. [source] The Intracoronary Electrocardiogram in Percutaneous Coronary InterventionJOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 1 2009ANDY SC YONG M.B.B.S. The technique of obtaining an epicardial electrocardiogram trace by connecting the guidewire during coronary angioplasty to an electrocardiogram lead has been used since 1985. The intracoronary electrocardiogram appears to be more sensitive than the surface electrocardiogram in detecting transient ischemia, particularly in the territory of the left anterior descending and left circumflex coronary arteries. Importantly, recent studies have shown the intracoronary electrocardiogram to be particularly useful in demonstrating pre- and postconditioning during interventional procedures, predicting periprocedural myocardial damage, and in the determination of regional viability in the catheterization laboratory. Barriers to the use of the intracoronary electrocardiogram in the clinical setting include the lack of standardized methods for acquiring and analyzing the intracoronary electrocardiogram, and the lack of commercially available continuous intracoronary monitoring systems to permit analysis while performing coronary interventions. Facilitating these relatively simple technical developments may permit optimal integration of the intracoronary electrocardiogram into the catheterization laboratory. [source] Raman spectroscopy in art and archaeologyJOURNAL OF RAMAN SPECTROSCOPY, Issue 10 2006Ludovic Bellot-Gurlet Abstract This paper gives a short overview of the Special Issue on Raman Spectroscopy in Art and Archaeology, with the papers collected after the ,3rd International Conference on the Application of Raman Spectroscopy in Art and Archaeology' held at the University Pierre et Marie Curie-Paris 6, Paris, France, from 31 August to 3 September, 2005. The contributions present an extended view of the work in the field, from technical developments and special analytical procedures to various applications. Copyright © 2006 John Wiley & Sons, Ltd. [source] Quantitative high-pressure pair distribution function analysisJOURNAL OF SYNCHROTRON RADIATION, Issue 5 2005John B. Parise The collection of scattering data at high pressure and temperature is now relatively straightforward thanks to developments at high-brightness synchrotron radiation facilities. Reliable data from powders, that are suitable for structure determination and Rietveld refinement, are routinely collected up to about 30,GPa in either a large-volume high-pressure apparatus or diamond anvil cell. In those cases where the total elastic scattering is of interest, as it is in the case of nano-crystalline and glassy materials, technical developments, including the use of focused high-energy X-rays (>80,keV), are advantageous. Recently completed experiments on nano-crystalline materials at the 1-ID beamline at the Advanced Photon Source suggest that quantitative data, suitable for pair distribution function analysis, can be obtained. [source] Clinical aspects and immune reactions in sarcoidosis,THE CLINICAL RESPIRATORY JOURNAL, Issue 2 2007Johan Grunewald Abstract Introduction:, Sarcoidosis is a granulomatous disorder of unknown aetiology, affecting young adults and frequently involving the lungs. Objective:, The aim of the present review was to give an overview of the clinical aspects in sarcoidosis. Results:, The majority of patients recover, but some develop a chronic disease that may result in fibrosis and respiratory failure. Besides the lungs, peripheral lymph nodes, the skin, the liver and the eyes are commonly affected as well. The genetic background, as well as environmental factors, is of importance for developing sarcoidosis. The incidence varies in different populations, in the Nordic countries approximately with 20/100 000 new patients yearly. Sarcoidosis is diagnosed when clinical and radiological findings are supported by histological evidence in the form of non-caseating epithelioid cell granulomas, and when other causes of these features are excluded. Patients in need of treatment are usually treated with corticosteroids, topically or as oral steroids. A clinical effect of immunomodulatory drugs blocking tumour necrosis factor (TNF), has been suggested from several case reports, while two controlled studies showed only minor effects; however, with a tendency to a more pronounced effect on patients with a more severe disease. The immune response in sarcoidosis, with a typical accumulation of CD4+ T-cells to the lungs, indicate the existence of specific antigens in this disease. Recently, antigens derived from infectious agents such as Mycobacteria and Proprionibacterium acnes have come into focus. Lymphocyte populations with immunoregulatory functions have recently been investigated and seem to be dysfunctional in sarcoidosis, opening the possibility of developing new treatment strategies in this disease. Conclusion:, Recent technical developments have provided better tools, enabling detailed and more thorough analyses of the inflammatory process in sarcoidosis. Please cite this paper as: Grunewald J. Clinical aspects and immune reactions in sarcoidosis. The Clinical Respiratory Journal 2007; 1:64,73. [source] 1226: Techniques and complications of anaesthesia for vitreoretinal surgery and a new technique of local anaesthesiaACTA OPHTHALMOLOGICA, Issue 2010K GOMBOSArticle first published online: 23 SEP 2010 Purpose Since the 1970s, the methods of vitrectomy procedures in ophthalmology have changed due to technical developments. Consequently certain procedures are less painful and less time consuming. On the other hand, due the modern technology more difficult cases can be operated, which may result in increase the time and strain of the operation. Methods General anaesthesia (GA) is one possibility, but it may have lots of side effects, can cause serious life threatening complications, is time consuming, expensive and sometimes to organise general anaesthesia leads to delay of the operation, consequently possibly hindering the proper timing of it. Despite these, the GA seemed to be necessary when a longer procedure planned. Results Using our method we could avoid some of the well-known complications of RBA and PBA. Painless operations were provided and the surgeons were satisfied with the anaesthesia. The serum Lidocain level was lower in cRBA compared with the single dose technique. Moreover the presence of postoperative pain could be reduced by using anaesthesia via cannula. Conclusion The benefits and disadvantages of cRBA will be apparent only by the spread of the new technique, which could also contribute to its improvement. This method means a perspective for postoperative pain relief. Hopefully more widespread use of this method helps continuous regional techniques to find their well deserved place in ophthalmic anaesthesia. [source] Quantitative Reflection Interference Contrast Microscopy (RICM) in Soft Matter and Cell AdhesionCHEMPHYSCHEM, Issue 16 2009Laurent Limozin Dr. Abstract Adhesion can be quantified by measuring the distance between the interacting surfaces. Reflection interference contrast microscopy (RICM), with its ability to measure inter-surface distances under water with nanometric precision and milliseconds time resolution, is ideally suited to studying the dynamics of adhesion in soft systems. Recent technical developments, which include innovative image analysis and the use of multi-coloured illumination, have led to renewed interest in this technique. Unambiguous quantitative measurements have been achieved for colloidal beads and model membranes, thus revealing new insights and applications. Quantification of data from cells shows exciting prospects. Herein, we review the basic principles and recent developments of RICM applied to studies of dynamical adhesion processes in soft matter and cell biology and provide practical hints to potential users. [source] | ||||||||||||||||