Technical Details (technical + detail)

Distribution by Scientific Domains


Selected Abstracts


Reoperative Grafting of the LAD System Using the LAST Approach: Technical Detail

JOURNAL OF CARDIAC SURGERY, Issue 6 2000
Marco Ricci M.D., Ph.D.
In such cases, however, the left upper lobe of the lung and the lingula may exert unwanted traction on the newly constructed coronary graft. Herein, we describe a detail of technique that eliminates this inconvenience. [source]


Carotid endarterectomy with simultaneous retrograde common carotid artery stenting: Technical Considerations,

CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 7 2008
Hernan A. Bazan MD
Abstract Carotid endarterectomy with simultaneous retrograde common carotid artery stenting (CEA-RCCAS) is performed with increasing frequency to treat tandem common and internal carotid artery stenoses. Technical details are not clearly delineated in the literature. Our procedure aims to maximize procedural ease and cerebral protection. Although the need for the endovascular component being performed first, followed by shunt placement, and the use of short wires and sheaths has been advocated, we describe the avoidance of shunt placement and the use of long sheaths to facilitate the procedure using local anesthesia and cervical blockade. Use of local anesthesia, avoidance of a shunt, and use of a long sheath may increase the procedural applicability and safety in some patients. CEA-RCCAS permits safe simultaneous treatment of tandem common and internal carotid artery stenoses. The use of technical adjuncts described here will permit further expansion of the procedure to allow additional patients to be treated in this hybrid fashion. © 2008 Wiley-Liss, Inc. [source]


Some peculiarities of load sharing control

INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 7 2003
Eduard Eitelberg
In the recently published book, ,Load Sharing Control' (Eitelberg, 1999), a frequency domain, loop-by-loop load sharing control system design methodology was developed and demonstrated with engineering examples. A number of new concepts were introduced in order to characterize some peculiarities that are not relevant in single-loop control systems, or have been overlooked in the general multivariable control system theory. Some of these concepts and peculiarities are introduced and explained in this paper with a minimum of technical detail. Copyright © 2003 John Wiley & Sons, Ltd. [source]


Development, standardization, and testing of a lexicon for reporting contrast-enhanced breast magnetic resonance imaging studies

JOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 6 2001
Debra M. Ikeda MD
Abstract The purpose of this study was to develop, standardize, and test reproducibility of a lexicon for reporting contrast-enhanced breast magnetic resonance imaging (MRI) examinations. To standardize breast MRI lesion description and reporting, seven radiologists with extensive breast MRI experience developed consensus on technical detail, clinical history, and terminology reporting to describe kinetic and architectural features of lesions detected on contrast-enhanced breast MR images. This lexicon adapted American College of Radiology Breast Imaging and Data Reporting System terminology for breast MRI reporting, including recommendations for reporting clinical history, technical parameters for breast MRI, descriptions for general breast composition, morphologic and kinetic characteristics of mass lesions or regions of abnormal enhancement, and overall impression and management recommendations. To test morphology reproducibility, seven radiologists assessed morphology characteristics of 85 contrast-enhanced breast MRI studies. Data from each independent reader were used to compute weighted and unweighted kappa (,) statistics for interobserver agreement among readers. The MR lexicon differentiates two lesion types, mass and non-mass-like enhancement based on morphology and geographical distribution, with descriptors of shape, margin, and internal enhancement. Lexicon testing showed substantial agreement for breast density (, = 0.63) and moderate agreement for lesion type (, = 0.57), mass margins (, = 0.55), and mass shape (, = 0.42). Agreement was fair for internal enhancement characteristics. Unweighted kappa statistics showed highest agreement for the terms dense in the breast composition category, mass in lesion type, spiculated and smooth in mass margins, irregular in mass shape, and both dark septations and rim enhancement for internal enhancement characteristics within a mass. The newly developed breast MR lexicon demonstrated moderate interobserver agreement. While breast density and lesion type appear reproducible, other terms require further refinement and testing to lead to a uniform standard language and reporting system for breast MRI. J. Magn. Reson. Imaging 2001;13:889,895. © 2001 Wiley-Liss, Inc. [source]


Charity Basket or Revolution: Beliefs, Experiences, and Context in Preservice Teachers' Service Learning

CURRICULUM INQUIRY, Issue 4 2000
David M. Donahue
Given what one observer calls the "vast disparity of definitions that faculty can bring to service learning,from what is basically the charity basket approach to the revolutionary," service learning can varytremendously, from reading to elderly residents of a nursing home to organizing a boycott of a sneaker company. With such diversity before teachers, what influences them in the way they design service learning? How do preservice teachers, for whom so many ideas about teaching are emerging, make such choices? Two case studies suggest that preservice teachers' beliefs, experiences, and the context where they teach play an important role related to if and how they use service learning. Beliefs and experiences are especially important because, although service learning is often presented as supporting apolitical values,empowerment and responsibility, for example,for which broad consensus exists, such values are also ambiguous and open to interpretation. Teacher educators and advocates of service learning need to acknowledge the ambiguous political nature of service and service learning. By doing so, they have an opportunity to make the political context of teaching explicit for preservice teachers. Such education in service learning for new teachers goes beyond "training" in the logistical and technical details of implementing a new pedagogy to thoughtful reflection on the value-laden act of teaching. [source]


The value of environmental modelling languages for building distributed hydrological models

HYDROLOGICAL PROCESSES, Issue 14 2002
Derek Karssenberg
Abstract An evaluation is made of the suitability of programming languages for hydrological modellers to create distributed, process-based hydrological models. Both system programming languages and high-level environmental modelling languages are evaluated based on a list of requirements for the optimal programming language for such models. This is illustrated with a case study, implemented using the PCRaster environmental modelling language to create a distributed, process-based hydrological model based on the concepts of KINEROS-EUROSEM. The main conclusion is that system programming languages are not ideal for hydrologists who are not computer programmers because the level of thinking of these languages is too strongly related to specialized computer science. A higher level environmental modelling language is better in the sense that it operates at the conceptual level of the hydrologist. This is because it contains operators that identify hydrological processes that operate on hydrological entities, such as two-dimensional maps, three-dimensional blocks and time-series. The case study illustrates the advantages of using an environmental modelling language as compared with system programming languages in fulfilling requirements on the level of thinking applied in the language, the reusability of the program code, the lack of technical details in the program, a short model development time and learnability. The study shows that environmental modelling languages are equally good as system programming languages in minimizing programming errors, but are worse in generic application and performance. It is expected that environmental modelling languages will be used in future mainly for development of new models that can be tailored to modelling aims and the field data available. Copyright © 2002 John Wiley & Sons, Ltd. [source]


Modularizing inference in large causal probabilistic networks

INTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 2 2003
Kristian G. Olesen
This article describes a number of implementation aspects of modular inference in large medical expert systems based on causal probabilistic networks. Examples are provided from the neuromuscular diagnosting system the muscle and nerve inference network (MUNIN). The inference procedure is outlined and the principal data structure underlying the inference procedure are described. A condensed summary of selected technical details of the inference procedure in causal probabilistic networks (CPNs) is provided. This is required for understanding the implemented modularization of the inference. The modularization of the inference implies a need for transfer of information between modules, which is realized by establishing communication channels between modules. Modules are also used to perform inference by conditioning, a method that reduces storage requirements to a manageable size and thereby prepares the way for MUNINs migration to common PCs. © 2003 Wiley Periodicals, Inc. [source]


Planning and the Technological Society: Discussing the London Plan

INTERNATIONAL JOURNAL OF URBAN AND REGIONAL RESEARCH, Issue 2 2010
YVONNE RYDIN
Abstract The sustainable development agenda has influenced the focus of urban planning policy in many countries and localities; this article argues that its influence has been much more widespread, affecting not just the content of planning but also its discourses and practices. This reflects more profound shifts within society , shifts that put the governance of technology firmly centre-place. Using a case study of the London Plan (the spatial development strategy for London), the discussion considers how recent debates on the Plan are being shaped by the need to focus on technological issues. Using Barry's and Feenberg's explorations of the technological society, the analysis identifies key features such as the contestation of evidence and expertise, the focus on technical details and the resultant reframing of policy discourse. The article concludes with suggestions as to the ways in which planning may change in the future. Résumé Les préoccupations liées au développement durable ont influé sur le c,ur des politiques d'urbanisme dans de nombreux pays et localités. Leur influence s'est révélée beaucoup plus vaste, affectant non seulement le contenu, mais aussi les discours et pratiques en matière d'aménagement. Cette situation traduit des mutations plus profondes de la société, mutations qui donnent à la gouvernance de la technologie une solide prééminence. À partir d'une étude de cas sur le London Plan (stratégie d'aménagement spatial de Londres), est examinée la façon dont les récents débats sur le Plan sont modelés par la nécessité de s'attacher aux aspects technologiques. S'appuyant sur les explorations de la société technologique menées par Barry et par Feenberg, l'analyse identifie des caractéristiques dominantes telles que la contestation des éléments factuels et de l'expertise, la focalisation sur des détails techniques et, donc, le recadrage du discours de l'action publique. La conclusion présente les possibles évolutions futures de l'aménagement du territoire. [source]


Factors affecting the outcome of peripheral nerve surgery

MICROSURGERY, Issue 4 2006
Hanno Millesi M.D.
Over the last 40 years, various factors that influence the outcome of peripheral nerve surgery have been recognized. Some of these factors, such as age of the patient and time interval between injury and surgery, cannot be controlled by the surgeon. On the other hand, other factors related to technical details are the topic of constant debate and improvement. Recently, surgeons have become increasingly aware of issues such as the environment at the site of the nerve repair, compression from an integument that is too tight, or muscle balance. © 2006 Wiley-Liss, Inc. Microsurgery, 2006. [source]


Protocol for clinical neurophysiologic examination of the pelvic floor

NEUROUROLOGY AND URODYNAMICS, Issue 6 2001
Simon Podnar
Abstract Clinical neurophysiologic examination of the pelvic floor is performed worldwide, but there is no consensus on the choice of tests, nor on technical details of individual methods. Standardized methods are, however, necessary to obtain their valid application in different laboratories for the purpose of collection of normative data, comparison of patient data and organization of multi-center studies. It is proposed that in patients with suspected "lower motor neuron" type lesions concentric needle electromyography (CNEMG) is the most informative test to detect pelvic floor denervation/reinnervation, and the external anal sphincter (EAS) muscle is the most appropriate muscle to be examined (either in isolation,when a selective lesion is suspected,or in addition to examination of other muscles). An algorithm consisting of standardized tests including a standardized approach to CNEMG examination of the EAS is presented. The proposed electrophysiologic assessment consists of a computer-assisted analysis of denervation and reinnervation features of the CNEMG signal, a qualitative assessment of reflex and voluntary activation of EAS motor units, and of electrical (or mechanical) elicitation of the bulbocavernosus reflex in those patients in whom manual anogenital stimulation failed to elicit a robust response in the EAS. The proposed protocol could serve as a basis for further studies on validity, sensitivity and specificity of electrophysiologic assessment in patients with different types of "lower motor neuron" involvement of pelvic floor muscles and sacral dysfunction. Neurourol. Urodynam. 20:669,682, 2001. © 2001 Wiley-Liss, Inc. [source]


Standardized procedure for measurement of nasal potential difference: An outcome measure in multicenter cystic fibrosis clinical trials,

PEDIATRIC PULMONOLOGY, Issue 5 2004
Thomas A. Standaert PhD
Abstract Patients with cystic fibrosis (CF) can be discriminated from healthy subjects by measurement of the nasal potential difference, which has become a useful outcome measure for therapies directed toward correcting defective electrolyte transport in CF. A standard operating procedure was developed by a CF Foundation clinical trials network, to be followed by all sites performing collaborative studies. Key variables in the measurement included type of voltmeter, exploring probe, reference electrodes, and solutions used to assess both sodium transport and chloride conductance. Eight sites submitted data on 3,8 normal and 4,5 CF subjects. Baseline voltage, an index of sodium transport, was ,18.2,±,8.3 mV (mean,±,SD) for normals, and ,45.3,±,11.4 mV for CF patients. There was no CFTR-mediated chloride secretion in CF subjects, as evidenced by the lack of response to perfusion with zero chloride,+,beta agonist solutions (+3.2,±,3.5 mV) vs. that in normals (,23.7,±,10.2 mV). The standardized nasal potential difference measurement minimizes variability between operators and study sites. Valid and consistent results can be attained with trained operators and attention to technical details. These data demonstrate the procedure to be sufficient for multicenter studies in the CF Foundation network. Pediatr Pulmonol. 2004; 37:385,392. © 2004 Wiely-Liss, Inc. [source]


New standards for networked reference services.

PROCEEDINGS OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE & TECHNOLOGY (ELECTRONIC), Issue 1 2003
Sponsored by SIG LT & ASIST Standards Committee
NISO (National Information Standards Organization) is developing a protocol for networked reference services. The intent of the protocol is to promote the interoperability of disparate online and networked reference systems. This session will provide an overview of the work of the committee developing the protocol including the motivation for its development, technical details of the protocol itself, and the implications it may have for reference services in the future. [source]


BrainProfileDB , a platform for integration of functional genomics data

PROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 6 2008
Johannes Schuchhardt Dr.
Abstract BrainProfileDB is a database system for integrating large sets of high throughput functional genomics data of the Human Brain Proteome Project (HBPP). Within HBPP (http://www.smp-proteomics.de/) the molecular pathology of neurodegenerative diseases is investigated, using complementary methods from transcriptomics, proteomics, toponomics and interaction measurements. Aim of the database system is to provide a broad spectrum of scientific users joined in the consortium with a practical integrated view on their data. Employing appropriate mapping techniques and levels of data representation the user is relieved from technical details of gene identification or experimental measurement technique. [source]


Rethinking groundwater monitoring at the Hanford Site

REMEDIATION, Issue 2 2000
Daniel Michael
Groundwater monitoring at Department of Energy's (DOE's) Hanford Site is a large, expensive undertaking serving multiple purposes, including compliance with regulations and DOE orders, remediation efforts under CERCLA, and sitewide risk evaluations. Like most large Federal facilities, the monitoring program currently in place has evolved and grown overtime as new requirements were established and groups were assigned to address them. DOE and its regulators simultaneously awakened to the fact that there was a need to reevaluate the monitoring activities at Hanford, to better integrate the program, to avoid duplicative sampling, to improve everyone's understanding of the performance of the network, and to evaluate whether adequate data could be collected for lower cost. This paper describes the approch that was developed to guide the rethinking effort with direct and extensive involvement of DOE, EPA, Washington Department of Ecology, Indian Tribes, and DOE Contractors, and how this approach was applied to a large portion of the site. Both the human element of the process (cultural change), as well as some of the technical details associated with the effort, including a flexible application of EPA's data quality objectives process, are discussed. [source]


Evaluation of a Navigation System for ENT with Surgical Efficiency Criteria,

THE LARYNGOSCOPE, Issue 4 2006
Gero Strau MD
Abstract The aim of this study is the evaluation of a navigation system (NaviBase) for ENT surgery. For this purpose, a new methodology for the evaluation of surgical and ergonomic system properties has been developed. The practicability of the evaluation instruments will be examined using the example of the overall assessment of the system in comparison with the current surgical standard and with other systems using clinical efficiency criteria. The evaluation is based on 102 ENT surgical applications; of these, 89 were functional endoscopic sinus surgeries (FESS). The evaluation of surgical and ergonomic performance factors was performed by seven ENT surgeons. To evaluate surgical system properties, the Level of Quality (LOQ) in 89 cases of the FESS was determined. It compares the existing information of the surgeon with that of the navigation system on a scale of 0 to 100 and with a mean value of 50 and places it in a relationship to the clinical impact. The intraoperative change of the planned surgical strategy (Change of Surgical Strategy) was documented. The ergonomic factors of the system with the categories of Overall Confidence (Trust), awareness of the situation (Situation Awareness), influence on the operating team, requirements for specific skills (Skill Set Requirement), and cognitive load (Workload Shift) were recorded for all surgical procedures as Level of Reliance (LOR). In the evaluation of the surgical system properties, an average evaluation of the quality of the information, as an LOQ of 63.59, resulted. Every second application of the navigation system (47.9%), on average, led to a change in the surgical strategy. An extension/enhancement of the indication of the endonasal approach through the use of the navigation system was shown in 7 of 102 (6.8%) cases. The completion of the resection in the FESS was rated by 74% of group I and 11% of group II as better in comparison with the standard approach. Total confidence shows a positive evaluation of 3.35 in the LOR. To supplement the evaluation of the navigation system, the technical parameters were included. The maximum deviation, Amax, of the displayed position of the reference value amounted to 1.93 mm. The average deviation was at 1.29 mm with an SD above all values, sd, of 0.29. The subsequent economic evaluation resulted in an effective average extra expenditure of time of 1.35 minutes per case. The overall evaluation of the system imparts application-relevant information beyond the technical details and permits comparability between different assistance systems. [source]


Current Applications of Microarrays in Head and Neck Cancer Research

THE LARYNGOSCOPE, Issue 2 2004
FRCS Eng, Giles C. Warner MSc
Abstract Objectives/Hypothesis: The objective was to introduce microarray technology and its applications in cancer research to the head and neck clinician. Study Design: Literature review combined with methodology and examples from the authors' experiences with microarray analysis of tumors of the head and neck. Methods: Search of literature and the authors' experience was made for technical details, alternative methods of data analysis, available bioinformatics tools, and applications of microarrays in cancer research. Results: Microarrays allow the simultaneous analysis of the expression of thousands of genes. The use of a well-developed microarray study design leads to informative results. There are various bioinformatics resources widely available to aid in the analysis of microarray data. However, there is not yet a gold standard for analysis because this methodology is still evolving. Conclusion: Microarray studies may allow researchers to identify genetic changes relevant to diagnosis and prognosis in patients with head and neck cancer. Although still relatively new, this powerful methodology has immense potential to aid in understanding of the genetic changes that are important in head and neck cancer. [source]


Lumbar Stimulation Belt for Therapy of Low-Back Pain

ARTIFICIAL ORGANS, Issue 1 2009
Dejan B. Popovi
Abstract We developed the STIMBELT, an electrical stimulation system that comprises a lumbar belt with up to eight pairs of embedded electrodes and an eight-channel electronic stimulator. The STIMBELT is an assistive system for the treatment of low-back pain (LBP). We describe here technical details of the system and summarize the results of its application in individuals with subacute and chronic LBP. The direct goals of the treatment were to relieve pain, reduce muscle spasms, increase strength and range of motion, and educate individuals with LBP in reducing the chances of its reoccurrence. The outcome measures include: a Visual Analogue Scale (VAS), the Oswestry LBP Disability Questionnaire, the Short Form (SF)-12 health survey, and the Manual Muscle Test. The results indicate significant benefits for individuals who use the STIMBELT in addition to the conventional therapy as opposed to only the conventional therapy. [source]


An introduction to molecular replacement

ACTA CRYSTALLOGRAPHICA SECTION D, Issue 1 2008
Philip Evans
Molecular replacement is fundamentally a simple trial-and-error method of solving crystal structures when a suitable related model is available. The underlying simplicity of the method is often obscured by the mathematical trickery required to make the searches computationally tractable. This introduction sketches the essential issues in molecular replacement without going into technical details. General search strategies are discussed and the alternative Patterson and likelihood approaches are outlined. [source]


The WASP project in the era of robotic telescope networks

ASTRONOMISCHE NACHRICHTEN, Issue 8 2006
D. J. Christian
Abstract We present the current status of the WASP project, a pair of wide angle photometric telescopes, individually called Super-WASP. SuperWASP-I is located in La Palma, and SuperWASP-II at Sutherland in South Africa. SW-I began operations in April 2004. SW-II is expected to be operational in early 2006. Each SuperWASP instrument consists of up to 8 individual cameras using ultra-wide field lenses backed by high-quality passively cooled CCDs. Each camera covers 7.8 × 7.8 sq degrees of sky, for nearly 500 sq degrees of total sky coverage. One of the current aims of the WASP project is the search for extra-solar planet transits with a focus on brighter stars in the magnitude range ,8 to 13. Additionally, WASP will search for optical transients, track Near-Earth Objects, and study many types of variable stars and extragalactic objects. The collaboration has developed a custom-built reduction pipeline that achieves better than 1 percent photometric precision. We discuss future goals, which include: nightly on-mountain reductions that could be used to automatically drive alerts via a small robotic telescope network, and possible roles of the WASP telescopes as providers in such a network. Additional technical details of the telescopes, data reduction, and consortium members and institutions can be found on the web site at: http://www.superwasp.org/. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]


Testing Measurement Invariance Using Item Response Theory in Longitudinal Data: An Introduction

CHILD DEVELOPMENT PERSPECTIVES, Issue 1 2010
Roger E. Millsap
Abstract, Item response theory (IRT) consists of a set of mathematical models for the probabilities of various responses to test items as a function of item and person characteristics. In longitudinal data, changes in measured variables can only be interpreted if important psychometric features of the measured variables are assumed invariant across time. Measurement invariance is invariance in the relation of a measure to the latent variable underlying it. Measurement invariance in longitudinal studies concerns invariance over time, and IRT provides a useful approach to investigating longitudinal measurement invariance. Commonly used IRT models are described, along with the representation of measurement invariance in IRT. The use of IRT for investigating invariance is then described, along with practical considerations in using IRT for this purpose. Conceptual issues, rather than technical details, are emphasized throughout. [source]


Horseshoe kidney transplantation: an overview

CLINICAL TRANSPLANTATION, Issue 6 2000
Otto B Stroosma
The horseshoe kidney is the most common anatomical renal variation. It represents a fusion anomaly, mainly at the lower poles, occurring between the 4th and 6th week of gestation. Horseshoe kidneys display a great variation in origin, number and size of the vasculature. Transplantation of these deviant kidneys can be done en bloc or they can be split into two halves and transplanted into two recipients, depending on the number of vessels and the anatomy of the urinary collecting system. A literature review reveals 31 case histories, published between 1975 and 1998. Of these 21 were transplanted into 38 recipients after division and ten were implanted en bloc. Nineteen grafts (41%) showed immediate function and 21 grafts (46%) showed delayed function. Thrombosis and acute rejection, leading to non-function was seen in six grafts (13%). The overall success rate was 87% with a mean follow-up of 22 months. The results of horseshoe kidney transplantation are good, provided that attention is paid to certain technical details. Because of donor scarcity, horseshoe kidneys should be used for transplantation. [source]