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The interplay between theta and alpha oscillations in the human electroencephalogram reflects the transfer of information between memory systems.

The exchange of information between the working and long-term memory system (WMS and LTMS) was investigated. We analyzed evoked theta and upper alpha desynchronization in a special memory task, designed to study the transfer of information between both memory systems. The results show that during attempts to retrieve information from the LTMS, evoked theta oscillations spread from anterior to posterior recording sites. When information actually is retrieved, the direction reverses and theta spreads to frontal sites. This time point--when direction reverses--varies between subjects to a large extent but is significantly correlated with memory performance and the onset of upper alpha desynchronization. We conclude that this phenomenon reflects the transfer of information between the WMS and LTMS

Adult↗

Justifying instrumental techniques of analytical chemistry.

In this paper, we argue that the foundations of chemistry rely as much on the methods of measurement as they do on categories of chemical substance. To some degree, chemists perform the work of knowledge engineering: designing complex systems for the efficient retrieval of information. Indeed, in some cases, methods of instrumental detection move to the forefront of attention. For example, researchers are expected to deploy optimization methods designed to maximize desired signal and minimize the damaging effects of noise. But in his important contributions to the development of high-resolution NMR spectrometers, Hans Primas used stochastic methods to reveal beneficial effects of noise for characterizing physical systems, demonstrating the value of noisy signals for nonlinear physical systems in chemistry.

Journal Article↗

Functional requirements for a HIS-RIS-PACS-interface design, including integration of "old" modalities.

Radiology, Information Systems (RIS) and Picture Archiving Systems (PACS), have the potential for immense rationalization of operations in radiology and hence for the improvement of health care, as well as the return of investments. These systems must, however, be carefully designed such that they support routine work rather than being an additional burden to radiology staff. Analyses show that comprehensive communication of patient demographic and clinical data between RIS, PACS and Hospital Information Systems (HIS) are necessary prerequisites to achieve cost effectiveness. Based on analyses of radiology operations in a large university primary care hospital, functional requirements and data structures for designing HIS/RIS/PACS interfaces are presented. These concern communication of past examinations, associated written reports and images, appointment scheduling, requests of new examinations, digitizing old analog X-ray films, access from RIS/PACS to other clinical data, and transfer of new radiology reports and relevant images. Consistency of all redundant data stored in the three systems is essential. A pragmatic, safe and inexpensive method of electronically integrating "old" modalities not fully "PACS capable" in the HIS/RIS/PACS world is presented.

Germany↗

Planning for effective use of on-line systems.

A perspective of developments in the field of computerized information retrieval is presented, and policies are suggested for the efficient use of on-line systems. Examples of MEDLINE, CHEMCON, AND TOXLINE searches are given with cost data and compared, where possible, with manual searches. The lowest costs were obtained with on-line searching by information scientists. MEDLINE is superior in quality to manual searching of Index Medicus, but on-line searching of Chemical Abstracts keywords is not an effective substitute for manual searching of Chemical Abstracts Substance Indexes.

Chemical Phenomena↗

Natural language processing of asthma discharge summaries for the monitoring of patient care.

A technique for monitoring healthcare via the processing of routinely collected narrative documentation is presented. A checklist of important details of asthma management in use in the Glasgow Royal Infirmary (GRI) was translated into SQL queries and applied to a database of 59 GRI discharge summaries analyzed by the New York University Linguistic String Project medical language processor. Tables of retrieved information obtained for each query were compared with the text of the original documents by physician reviewers. Categories (unit = document) were: (1) information present, retrieved correctly; (2) information not present; (3) information present, retrieved with minor or major error; (4) information present, retrieved with minor or major omissions. Category 2 (physician "documentation score") could be used to prioritize manual review and guide feedback to physicians to improve documentation. The semantic structuring and relative completeness of retrieved data suggest their potential use as input to further quality assurance procedures.

Asthma↗

Six characteristics of effective structured reporting and the inevitable integration with speech recognition.

The reporting of radiological images is undergoing dramatic changes due to the introduction of two new technologies: structured reporting and speech recognition. Each technology has its own unique advantages. The highly organized content of structured reporting facilitates data mining and billing, whereas speech recognition offers a natural succession from the traditional dictation-transcription process. This article clarifies the distinction between the process and outcome of structured reporting, describes fundamental requirements for any effective structured reporting system, and describes the potential development of a novel, easy-to-use, customizable structured reporting system that incorporates speech recognition. This system should have all the advantages derived from structured reporting, accommodate a wide variety of user needs, and incorporate speech recognition as a natural component and extension of the overall reporting process.

Humans↗

[Performance and cost transparency as quality assurance measures].

The use of a Hospital Information System--Network Configuration, Information--Storage and Retrieval, Medical-Administration and -Documentation--lead in the Department of Surgery to positive effects concerning transparency and consciousness of costs and allowed an accurate budget planing and controlling of proceeds.

Budgets↗

Bridges between health care research evidence and clinical practice.

Research is producing increasing amounts of important new evidence for health care, but there is a large gap between what this evidence shows can be done and the care that most patients actually receive. An important reason for this gap is the extensive processing that evidence requires before application. This article discusses a three-step model for bridging research evidence to management of clinical problems: getting the evidence straight, formulating evidence-based clinical policies, and applying evidence-based clinical policies at the right place and time. This model is purposely broad in scope and provides a framework for coordinating efforts to support evidence-based medical care. The authors' purpose is to represent the roles of health informatics in the context of the roles of all the key players, including health care researchers and practitioners, health care organizations, and the public. Health informatics has already made important contributions to bridging evidence to practice, including improving evidence retrieval, evaluation, and synthesis; new evidence-based information products; and computerized aids for facilitating the use of these products during clinical decision making. However, much more innovation and coordination are needed. The authors call for health informaticians to pay balanced attention to 1) the quality of evidence embodied in information innovations, 2) the performance of technologies and systems that retrieve, prepare, disseminate, and apply evidence, and 3) the fit of information tools to the specific clinical circumstances in which evidence is to be applied. Effective interdisciplinary teams that include health services researchers and other evidence experts, clinical practitioners, informaticians, and health care managers are needed to achieve success. Informaticians can make increasingly important contributions to the transfer of health care research by joining such teams.

Decision Making, Organizational↗

Participative HIS development: an approach and a case study.

User participation in HIS development is considered essential for achieving systems implementation success. Realizing a participative HIS development, where users are full members of the development team, requires not only choosing an appropriate methodology but also organizing the participation process in a way that is tailored to the particular situation in order to achieve the desired results. A general approach to this problem is presented in this paper. An application of the approach to the particular context of a Greek hospital is described.

Attitude to Computers↗

Online clustering algorithms for radar emitter classification.

Radar emitter classification is a special application of data clustering for classifying unknown radar emitters from received radar pulse samples. The main challenges of this task are the high dimensionality of radar pulse samples, small sample group size, and closely located radar pulse clusters. In this paper, two new online clustering algorithms are developed for radar emitter classification: One is model-based using the Minimum Description Length (MDL) criterion and the other is based on competitive learning. Computational complexity is analyzed for each algorithm and then compared. Simulation results show the superior performance of the model-based algorithm over competitive learning in terms of better classification accuracy, flexibility, and stability.

Algorithms↗

Physician's information customizer (PIC): using a shareable user model to filter the medical literature.

The practice of medicine is information-intensive. From reviewing the literature to formulating therapeutic plans, each physician handles information differently. Yet rarely does a representation of the user's information needs and preferences--a user model--get incorporated into information management tools, even though we might reasonably expect better acceptance and effectiveness if the tools' presentation and processing were customized to the user. We developed the Physician's Information Customizer (PIC), which generates a shareable user model that can be used in any medical information-management application. PIC elicits the stable, long-term attributes of a physician through simple questions about her specialty, research focus, areas of interest, patient characteristics (e.g., ages), and practice locale. To show the utility of this user model in customizing a medical informatics application, PIC custom-filters and ranks articles from Medline, using the user model to determine what would be most interesting to the user. Preliminary evaluation on all 99 unselected articles from a recent issue of six prominent medical journals shows that PIC ranks 66% of the articles as the user would. This demonstrates the feasibility of using easily acquired physician attributes to develop a user model that can successfully filter articles of interest from a large undifferentiated collection. Further testing and development is required to optimize the custom filter and to determine which characteristics should be included in the shareable user model and which should be obtained by individual applications.

Algorithms↗

A review of the CLIP system for the quantitative analysis of two-dimensional electrophoresis gels.

This paper reviews the CLIP image processing system for the complete analysis of two-dimensional electrophoresis images. The analysis problem for two-dimensional gel images can be broken down into three issues: segmentation of individual gel images, alignment and comparison of pairs of gel images, and information storage and retrieval. This paper describes these problems and reviews how the CLIP system handles each of them. Segmentation is the location and isolation of each protein spot on an individual gel image and also the extraction of individual spot data such as position, area and volume. There are three basic stages: background field correction, noise filtering, spot detection and information extraction. Alignment and comparison of gel images involves matching protein spots between two gels. This can be quite difficult because there is not a simple relationship which can transform one gel image onto another. The database issues concern storing all the information which has been obtained from the above operations such that retrieval of this information can be readily performed. The advantage of the CLIP system over others is speed of processing. CLIP series computers use one processor for every pixel of the camera image such that image processing algorithms run in parallel. The main disadvantage is in the cost of these machines. With the declining trend in the cost of parallel processors, these machines will become more and more viable alternatives. This papers reviews the algorithms for the analysis of two-dimensional gels. It is shown that CLIP is flexible enough to perform more than one type of algorithm for a particular operation.

Algorithms↗

The interaction of domain knowledge and linguistic structure in natural language processing: interpreting hypernymic propositions in biomedical text.

Interpretation of semantic propositions in free-text documents such as MEDLINE citations would provide valuable support for biomedical applications, and several approaches to semantic interpretation are being pursued in the biomedical informatics community. In this paper, we describe a methodology for interpreting linguistic structures that encode hypernymic propositions, in which a more specific concept is in a taxonomic relationship with a more general concept. In order to effectively process these constructions, we exploit underspecified syntactic analysis and structured domain knowledge from the Unified Medical Language System (UMLS). After introducing the syntactic processing on which our system depends, we focus on the UMLS knowledge that supports interpretation of hypernymic propositions. We first use semantic groups from the Semantic Network to ensure that the two concepts involved are compatible; hierarchical information in the Metathesaurus then determines which concept is more general and which more specific. A preliminary evaluation of a sample based on the semantic group Chemicals and Drugs provides 83% precision. An error analysis was conducted and potential solutions to the problems encountered are presented. The research discussed here serves as a paradigm for investigating the interaction between domain knowledge and linguistic structure in natural language processing, and could also make a contribution to research on automatic processing of discourse structure. Additional implications of the system we present include its integration in advanced semantic interpretation processors for biomedical text and its use for information extraction in specific domains. The approach has the potential to support a range of applications, including information retrieval and ontology engineering.

Abstracting and Indexing↗

Knowledge representation and retrieval using conceptual graphs and free text document self-organisation techniques.

Hospitals generate and store a large amount of clinical data each year, a significant portion of which is in free text format. Conventional database storage and retrieval algorithms are incapable of effectively processing free text medical data. The rich information and knowledge buried in healthcare records are unavailable for clinical decision-making. We examined a number of techniques for structuring and processing free text documents to effective and efficient for information retrieval and knowledge discovery. One critical success criterion is that the complexity of the techniques must be polynomial both in space and time for them to be able to cope with very large databases. We used conceptual graphs (CG) to capture the structure and semantic information/knowledge contained within the free text medical documents. Ordering and self-organising techniques (lattice techniques and knowledge space) were used to improve organisation of concepts from standard medical nomenclatures and large sets of free text medical documents. Pair-wise union of CG was performed to identify the common generalisation structure and a lattice structure of these CG documents. A combination of all three techniques allowed us to organise a set of 9000 discharge summaries into a generalisation hierarchy that supported efficient and rich information/knowledge retrieval.

Classification↗

Workflow-enabled distributed component-based information architecture for digital medical imaging enterprises.

Few information systems today offer a flexible means to define and manage the automated part of radiology processes, which provide clinical imaging services for the entire healthcare organization. Even fewer of them provide a coherent architecture that can easily cope with heterogeneity and inevitable local adaptation of applications and can integrate clinical and administrative information to aid better clinical, operational, and business decisions. We describe an innovative enterprise architecture of image information management systems to fill the needs. Such a system is based on the interplay of production workflow management, distributed object computing, Java and Web techniques, and in-depth domain knowledge in radiology operations. Our design adapts the approach of "4+1" architectural view. In this new architecture, PACS and RIS become one while the user interaction can be automated by customized workflow process. Clinical service applications are implemented as active components. They can be reasonably substituted by applications of local adaptations and can be multiplied for fault tolerance and load balancing. Furthermore, the workflow-enabled digital radiology system would provide powerful query and statistical functions for managing resources and improving productivity. This paper will potentially lead to a new direction of image information management. We illustrate the innovative design with examples taken from an implemented system.

Computer Communication Networks↗