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PubMed1993

The conceptual validity of a taxonomy of nursing interventions.

The purpose of this paper is to report validity evidence for the nursing intervention taxonomy developed as part of the Nursing Intervention Lexicon and Taxonomy (NILT) Study. Using eclectic classification methods of library science, cognitive science, nursing science and computational linguistics, a taxonomy of nursing interventions consisting of seven categories was developed. These categories which incorporate care as a central concept are described and defined, and prototypical examples of each category are presented. Brinberg & McGrath's validity schema provides the framework within which evidence for validity as value, validity as correspondence and validity as generalizability were examined. Comparison of the NILT categories with previously published categorizations of nursing functions and interventions provides strong support for the validity of this classification. Additionally, comparison of the NILT categories with two internationally derived categorizations of nursing functions supports the robustness or generalizability of the NILT classification.

Job Description↗
PubMed2006

Counterions between charged polymers exhibit liquid-like organization and dynamics.

Current understanding of electrostatics in water is based on mean-field theories like the Poisson-Boltzmann formalism and its approximations, which are routinely used in colloid science and computational biology. This approach, however, breaks down for highly charged systems, which exhibit counterintuitive phenomena such as overcharging and like-charge attraction. Models of counterion correlations have been proposed as possible explanations, but no experimental comparisons are available. Here, collective dynamics of counterions that mediate like-charge attraction between F-actin filaments have been directly observed in aqueous solution using high-resolution inelastic x-ray scattering down to molecular length-scales. We find a previously undescribed acoustic-like phonon mode associated with correlated counterions. The excitation spectra at high wave-vector Q reveal unexpected dynamics due to ions interacting with their "cages" of nearest neighbors. We examine this behavior in the context of intrinsic charge density variations on F-actin. The measured speed of sound and collective relaxation rates in this liquid agree surprisingly well with simple model calculations.

Actins↗
PubMed2003

Like-charge attraction between polyelectrolytes induced by counterion charge density waves.

Electrostatics in aqueous media is commonly understood in terms of screened Coulomb interactions, where like-charged objects, such as polyelectrolytes, always repel. These intuitive expectations are based on mean field theories, such as the Poisson-Boltzmann formalism, which are routinely used in colloid science and computational biology [Israelachvili, J. (1992) Intermolecular and Surface Forces (Academic, London), 2nd ed.]. Like-charge attractions, however, have been observed in a variety of systems [Gelbart, W. M., Bruinsma, R. F., Pincus, P. A. & Parsegian, V. A. (2000) Phys. Today 53, 38-44]. Intense theoretical scrutiny over the last 30 years suggests that counterions play a central role, but no consensus exists for the precise mechanism. We have directly observed the organization of multivalent ions on cytoskeletal filamentous actin (a well defined biological polyelectrolyte) by using synchrotron x-ray diffraction and discovered an unanticipated symmetry-breaking collective counterion mechanism for generating attractions. Surprisingly, the counterions do not form a lattice that simply follows actin's helical symmetry; rather, the counterions organize into "frozen" ripples parallel to the actin filaments and form 1D charge density waves. Moreover, this 1D counterion charge density wave couples to twist distortions of the oppositely charged actin filaments. This general cooperative molecular mechanism is analogous to the formation of polarons in ionic solids and mediates attractions by facilitating a "zipper-like" charge alignment between the counterions and the polyelectrolyte charge distribution. We believe these results can fundamentally impinge on our general understanding of electrostatics in aqueous media and are relevant to a wide range of colloidal and biomedical processes.

Actins↗
PubMed2004

From innovation to social norm: bounded normative influence.

CORRECTION: Every innovation begins as a deviation from existing social norms. Given the strong effect of social norms and pressure, how can any innovation ever diffuse to the point where it becomes a new social norm? The seeming paradox of how a minority can influence the majority has not been explained well by prevailing social science theory. Computer simulations of the diffusion of a new behavior within the social network of a Bangladesh village led to the discovery of a new principle of social change that resolves this paradox. The results revealed the important but overlooked role played by boundaries that emerge within a social network and how such local boundaries affect the creation of a new social norm. A minority position can become the social norm by means of the process of bounded normative influence. As long as a minority maintains its majority status within its own, locally bounded portion of the network, then it can survive, recruit converts in the near surround, and establish its behavior as the norm for the network as a whole. The process is accelerated when the minority subgroup is centrally located in the network and communicates more frequently and persuasively than the majority.

Bangladesh↗
PubMed2026

Using cancer profiles to identify synthetic lethal therapeutic targets and predictive biomarkers in cancer gene dependency data.

MOTIVATION: Large scale loss-of-function screens utilising CRISPR or siRNA can provide profound insights into the importance of individual genes for the survival of a cancer cell and can drive the identification of therapeutic targets and biomarkers, and the development of targeted drugs. However, the analysis of these data and the substantial bodies of metadata that relate to them, is technically challenging and typically requires substantial expertise in data science and computer coding. RESULTS: To facilitate the analysis of cancer gene dependency data by cancer biologists and clinical scientists, we have developed DepMine-a computational toolkit providing a powerful system for framing complex queries relating cancer gene dependency to the underlying genetic changes that occur in cancer cells. DepMine identifies synthetic lethal relationships between putative target genes and complex 'cancer profiles' built from user-specified combinations of mutations, copy-number variation, and expression levels, and can refine these to optimal biomarker definitions for target dependency. AVAILABILITY: The Python implementation of DepMine and associated data files can be obtained at https://github.com/UOSbioinformaticslab/depmine and is free to academics and Not-For-Profit organisations. The DepMine release referenced in this paper is archived as DOI: 10.5281/zenodo.19570601.

Humans↗
PubMed1999

Adjunct aids in instructional prose: a multimedia study with deaf college students.

A computer-based science lesson was administered to 144 deaf college students grouped into low, middle, and high reading ability levels. Five instructional conditions were compared: (1) text only, (2) text and content movies, (3) text and sign movies, (4) text and adjunct questions, and (5) all of these together (full condition). The low reading level subjects in the adjunct question and full conditions demonstrated immediate, factual learning performance comparable to that of the high reading level subjects in the text-only condition. These and other results of this investigation suggest the compensatory potential of adjunct aids and associated mathemagenic activities to improve factual learning from instructional prose for low reading ability students.

Journal Article↗
PubMed2002

The computational challenges of Earth-system science.

The Earth system--comprising atmosphere, ocean, land, cryosphere and biosphere--is an immensely complex system, involving processes and interactions on a wide range of space- and time-scales. To understand and predict the evolution of the Earth system is one of the greatest challenges of modern science, with success likely to bring enormous societal benefits. High-performance computing, along with the wealth of new observational data, is revolutionizing our ability to simulate the Earth system with computer models that link the different components of the system together. There are, however, considerable scientific and technical challenges to be overcome. This paper will consider four of them: complexity, spatial resolution, inherent uncertainty and time-scales. Meeting these challenges requires a significant increase in the power of high-performance computers. The benefits of being able to make reliable predictions about the evolution of the Earth system should, on their own, amply repay this investment.

Atmosphere↗
PubMed1999

Estimating the number of clusters in multivariate data by self-organizing maps.

Determining the structure of data without prior knowledge of the number of clusters or any information about their composition is a problem of interest in many fields, such as image analysis, astrophysics, biology, etc. Partitioning a set of n patterns in a p-dimensional feature space must be done such that those in a given cluster are more similar to each other than the rest. As there are approximately Kn/K! possible ways of partitioning the patterns among K clusters, finding the best solution is very hard when n is large. The search space is increased when we have no a priori number of partitions. Although the self-organizing feature map (SOM) can be used to visualize clusters, the automation of knowledge discovery by SOM is a difficult task. This paper proposes region-based image processing methods to post-processing the U-matrix obtained after the unsupervised learning performed by SOM. Mathematical morphology is applied to identify regions of neurons that are similar. The number of regions and their labels are automatically found and they are related to the number of clusters in a multivariate data set. New data can be classified by labeling it according to the best match neuron. Simulations using data sets drawn from finite mixtures of p-variate normal densities are presented as well as related advantages and drawbacks of the method.

Algorithms↗
PubMed2000

Automated protein modelling--the proteome in 3D.

Functional analysis of the proteins discovered in fully sequenced genomes represent the next major challenge of life science research. Computational methods play an increasingly important role in this activity. Among them, comparative protein modelling will play a major role in this challenge, especially in the light of the Structural Genomics programmes about to be started around the world. In recent years, much progress has been made in automating these methods, enabling the production of models for genome scale problems. In this review we discuss how protein models can be applied to functional analysis, as well as some of the current issues and limitations inherent to these methods.

Animals↗
PubMedDate not supplied

[Information system in nursing: interacion of tacit-explicit knowledge].

The present article aims to trace some theoretical and conceptual considerations on information systems in nursing, seeking to point out the knowledge based on the clinical practice evidences to construct a model of system integrated to the conceptual structures, formed by the combination of three sciences: information, computing and nursing. This knowledge can systematically describe and explain the necessary phenomena to develop a comprehensive information system that contribute for nursing records improvement and to consolidate a mechanism to provide basic measuring of costs, quality, patient access to care, and results of this care.

Clinical Competence↗
PubMed2006

Can business and economics students perform elementary arithmetic?

Business and economics majors (N=146) were tested on the D'Amore Test of Elementary Arithmetic, which employs third-grade test items from 1932. Only 40% of the subjects passed the test by answering 10 out of 10 items correctly. Self-predicted scores were a good predictor of actual scores, but performance was not associated with demographic variables, grades in calculus courses, liking for science or computers, or mathematics anxiety. Scores decreased over the subjects' initial years on campus. The hardest test item, with an error rate of 23%, required the subject to evaluate (36 x 7) + (33 x 7). The results are similar to those of Standing in 2006, despite methodological changes intended to maximize performance.

Commerce↗
PubMed2001

Versatile computerized system for tracking and analysis of water maze tests.

A crucial step in the estimation of properties of compounds in behavioral experiments is the quantification and description of the different effects observed. The goal of the present work was the automation of the Morris water maze test, one of the most popular behavioral methods for the study of animal memory. An original system was developed that provides fast and accurate tracking of animals, storage of the results in the database and video archive and a means of analyzing the results. This computerized version of the Morris water maze test permits the quantification of such vague characteristics of cognitive function as the "directionality" of search of the hidden platform after a standard training series. The suggested parameters made it possible to discriminate cognitive properties of the novel compounds from other behavioral effects affecting escape latency. The effectiveness of this system was demonstrated in two experiments with neurochemically lesioned and drug-treated rats.

Analysis of Variance↗
PubMed2001

EthoVision: a versatile video tracking system for automation of behavioral experiments.

The need for automating behavioral observations and the evolution of systems developed for that purpose is outlined. Video tracking systems enable researchers to study behavior in a reliable and consistent way and over longer time periods than if they were using manual recording. To overcome limitations of currently available systems, we have designed EthoVision, an integrated system for automatic recording of activity, movement, and interactions of animals. The EthoVision software is presented, highlighting some key features that separate EthoVision from other systems: easy file management, independent variable definition, flexible arena and zone design, several methods of data acquisition allowing identification and tracking of multiple animals in multiple arenas, and tools for visualization of the tracks and calculation of a range of analysis parameters. A review of studies using EthoVision is presented, demonstrating the system's use in a wide variety of applications. Possible future directions for development are discussed.

Animals↗