Research papers

The neighbor-joining method: a new method for reconstructing phylogenetic trees.

Naruya Saitou, M Nei

A new method called the neighbor-joining method is proposed for reconstructing phylogenetic trees from evolutionary distance data. The principle of this method is to find pairs of operational taxonomic units (OTUs [= neighbors]) that minimize the total branch length at each stage of clustering of OTUs starting with a starlike tree. The branch lengths as well as the topology of a parsimonious tree can quickly be obtained by using this method. Using computer simulation, we studied the efficiency of this method in obtaining the correct unrooted tree in comparison with that of five other tree-making methods: the unweighted pair group method of analysis, Farris's method, Sattath and Tversky's method, Li's method, and Tateno et al.'s modified Farris method. The new, neighbor-joining method and Sattath and Tversky's method are shown to be generally better than the other methods.

Handbook of Theory and Research for the Sociology of Education.

David O'Shea, John G. Richardson

The first of its kind, this handbook synthesizes major advances in the sociology of education over the past several decades. It incorporates both a systematic review of significant theoretical and empirical work and challenging original contributions by distinguished American, English, and French sociologists. In his introduction, John G. Richardson traces the development of the sociology of education and reviews the important classical European works in which this discipline is grounded. Each chapter, devoted to a major topic in the field, provides both a review of the literature and an exposition of an original thesis. The inclusion of subjects outside traditional sociological concern--such as the historical foundations of education and the sociology of special education--gives an interdisciplinary scope that enhances the volume's usefulness.

Inhibited Spontaneous Emission in Solid-State Physics and Electronics

Eli Yablonovitch

It has been recognized for some time that the spontaneous emission by atoms is not necessarily a fixed and immutable property of the coupling between matter and space, but that it can be controlled by modification of the properties of the radiation field. This is equally true in the solid state, where spontaneous emission plays a fundamental role in limiting the performance of semiconductor lasers, heterojunction bipolar transistors, and solar cells. If a three-dimensionally periodic dielectric structure has an electromagnetic band gap which overlaps the electronic band edge, then spontaneous emission can be rigorously forbidden.

A Comprehensive Grammar of the English Language

Paul J. Beauvais, Randolph Quirk, Sidney Greenbaum, Geoffrey Leech, Jan Svartvik

A Comprehensive grammar of the English language , A Comprehensive grammar of the English language , کتابخانه دانشگاه علوم پزشکی و خدمات بهداشتی درمانی کرمان

Single-step method of RNA isolation by acid guanidinium thiocyanate-phenol-chloroform extraction

Piotr Chomczyński, Nicoletta Sacchi

Single-Step Method of RNA Isolation by Acid Guanidinium Thiocyanate–Phenol–Chloroform Extraction

P CHOMZYNSKI

Co-Integration and Error Correction: Representation, Estimation, and Testing

Robert F. Engle, C. W. J. Granger

The relationship between co-integration and error correction models, first suggested in Granger (1981), is here extended and used to develop estimation procedures, tests, and empirical examples. If each element of a vector of time series x first achieves stationarity after differencing, but a linear combination a'x is already stationary, the time series x are said to be co-integrated with co-integrating vector a. There may be several such co-integrating vectors so that a becomes a matrix. Interpreting a'x,= 0 as a long run equilibrium, co-integration implies that deviations from equilibrium are stationary, with finite variance, even though the series themselves are nonstationary and have infinite variance. The paper presents a representation theorem based on Granger (1983), which connects the moving average, autoregressive, and error correction representations for co-integrated systems. A vector autoregression in differenced variables is incompatible with these representations. Estimation of these models is discussed and a simple but asymptotically efficient two-step estimator is proposed. Testing for co-integration combines the problems of unit root tests and tests with parameters unidentified under the null. Seven statistics are formulated and analyzed. The critical values of these statistics are calculated based on a Monte Carlo simulation. Using these critical values, the power properties of the tests are examined and one test procedure is recommended for application. In a series of examples it is found that consumption and income are co-integrated, wages and prices are not, short and long interest rates are, and nominal GNP is co-integrated with M2, but not M1, M3, or aggregate liquid assets.

Integrative reviews of nursing research

Lawrence H.Ganong

Integrative reviews of research are a valuable part of the process of creating and organizing a body of literature. It has been argued that integrative reviews should be held to the same standards of clarity, rigor, and replication as primary research. In this paper methods for conducting an integrative review are discussed. Seventeen reviews from nursing journals were examined and compared with a proposed set of criteria for reviews. The results indicated that the majority of integrative reviews in nursing fell short of primary research standards. Guidelines for conducting more rigorous reviews are presented.

An Intrusion-Detection Model

Dorothy E. Denning

A model of a real-time intrusion-detection expert system capable of detecting break-ins, penetrations, and other forms of computer abuse is described. The model is based on the hypothesis that security violations can be detected by monitoring a system's audit records for abnormal patterns of system usage. The model includes profiles for representing the behavior of subjects with respect to objects in terms of metrics and statistical models, and rules for acquiring knowledge about this behavior from audit records and for detecting anomalous behavior. The model is independent of any particular system, application environment, system vulnerability, or type of intrusion, thereby providing a framework for a general-purpose intrusion-detection expert system.

A new method of classifying prognostic comorbidity in longitudinal studies: Development and validation

Mary E. Charlson, Peter Pompei, Kathy L. Aleš, C. Ronald MacKenzie

The Practice of Nursing Research: Conduct, Critique, & Utilization

Nancy Nancy, Burns, Suan K .Grove

Unit I: Introduction to Nursing Research. Discovery of the World of Nursing Research. The Evolution of Research in Nursing. Introduction to Quantitative Research. Introduction to Qualitative Research. Unit II: The Research Process. Research Problem and Purpose. Review of Relevant Literature. Frameworks. Objectives, Questions and Hypotheses. Ethics in Research. Understanding Research Design. Selecting a Research Design. Sampling. The Concepts of Measurement. Measurement Strategies in Nursing. Data Collection and Management. Concepts of Statistical Theory. Descriptive and Exploratory Analyses. Bivariate Inferential Data Analyses. Advanced Statistical Analyses. Qualitative Research Methodology. Outcomes Research. Interpreting Research Outcomes. Communicating Research Findings. Unit III: Strategies for Using Research in Practice. Critical Analysis of Nursing Studies. Utilization of Research in Nursing Practice. Unit IV: Seeking Support for Research Activities. Proposal Writing for Research Approval. Seeking Funding for Research.

A Computational Approach to Edge Detection

John Canny

This paper describes a computational approach to edge detection. The success of the approach depends on the definition of a comprehensive set of goals for the computation of edge points. These goals must be precise enough to delimit the desired behavior of the detector while making minimal assumptions about the form of the solution. We define detection and localization criteria for a class of edges, and present mathematical forms for these criteria as functionals on the operator impulse response. A third criterion is then added to ensure that the detector has only one response to a single edge. We use the criteria in numerical optimization to derive detectors for several common image features, including step edges. On specializing the analysis to step edges, we find that there is a natural uncertainty principle between detection and localization performance, which are the two main goals. With this principle we derive a single operator shape which is optimal at any scale. The optimal detector has a simple approximate implementation in which edges are marked at maxima in gradient magnitude of a Gaussian-smoothed image. We extend this simple detector using operators of several widths to cope with different signal-to-noise ratios in the image. We present a general method, called feature synthesis, for the fine-to-coarse integration of information from operators at different scales. Finally we show that step edge detector performance improves considerably as the operator point spread function is extended along the edge.

Learning representations by back-propagating errors

David E. Rumelhart, Geoffrey E. Hinton, Ronald J. Williams

Experience and Education

John Dewey

"Experience and Education offers educators and teachers a positive philosophy of education. It evaluates the practices of both the traditional and the progressive schools and lucidly sets forth the defects of each of them. The volume, however, is in no sense controversial. Dr. Dewey, while considering current educational issues, interprets the meaning of a philosophicy of experience and the educational implications of the scientific method. A learning situation is described and concretely illustrated. The meanings of freedom, activities, discipline, control, and organized subject matter are here expounded within the context of educative experience as a process implying both continuity and interaction. Experience and Education defends no "ism". It offers no compromise. It steers clear of eclectic patching. Education itself is interpreted. Professional educators and laymen alike will here find definite answers to moot questions, but these answers are integral parts of an educational philosophy which makes possible united efforts in educational leadership. Here is a new light which will dissolve the fog now enveloping educational theory." (4th cover of the 60th anniversary edition) (http://books.google.com/books?id=UE2EusaU53IC&printsec=frontcover&hl=fr#v=onepage&q&f=false)

Meta-analysis in clinical trials

Rebecca DerSimonian, Nan M. Laird

Biology ofEpidinocarsis [=Apoanagyrus] lopezi [Hymenoptera: Encyrtidae] an exotic parasite of cassava mealybug,Phenacoccus manihoti [Homoptera: Pseudococcidae] in Nigeria

J. A. Odebiyi, Aimé H. Bokonon‐Ganta

The moderator-mediator variable distinction in social psychological research: Conceptual, strategic, and statistical considerations.

Reuben M. Baron, David A. Kenny

In this article, we attempt to distinguish between the properties of moderator and mediator variables at a number of levels. First, we seek to make theorists and researchers aware of the importance of not using the terms moderator and mediator interchangeably by carefully elaborating, both conceptually and strategically, the many ways in which moderators and mediators differ. We then go beyond this largely pedagogical function and delineate the conceptual and strategic implications of making use of such distinctions with regard to a wide range of phenomena, including control and stress, attitudes, and personality traits. We also provide a specific compendium of analytic procedures appropriate for making the most effective use of the moderator and mediator distinction, both separately and in terms of a broader causal system that includes both moderators and mediators.

Future paths for integer programming and links to artificial intelligence

Fred Glover

Nursing theorists and their work

Martha Raile Alligood

Nursing: Concepts of Practice

Helen Erickson, Dorothea E. Orem

PERSONAL, INTERPERSONAL, AND SOCIAL FEATURES OF NURSING . Understanding nursing . Nursing and society . Interpersonal features of nursing . The human condition and care requirements of individuals . Health care situations and nursing . THE FORMALIZATION OF NUSRING KNOWLEDGE . The nature of science in practice fields o Generalizations about nursing: the self-care deficit theory of nursing and its constituent theories . Stages of development of nursing knowledge o VARIABLES OF NURSING SYSTEMS o Views of nursing and views of human kind o Therapeutic self-care demand: an action demand . Self-care agency: a patient power . Nursing agency: a nurse power . Dependant care agents and dependant care systems in relation to nurses and nursing systems o THE PRACTICE OF NURSING o Positive mental health of individuals in nursing practice situations o The practice of nursing: the individual as the unit of service . The practice of nursing in multiperson situations, family, community . Nurses . Appendixes A, B, C

Modeling of swirl in turbulent flow systems

David G. Sloan, Philip J. Smith, L.D. Smoot

An introduction to hidden Markov models

L. R. Rabiner, Biing‐Hwang Juang

The basic theory of Markov chains has been known to mathematicians and engineers for close to 80 years, but it is only in the past decade that it has been applied explicitly to problems in speech processing. One of the major reasons why speech models, based on Markov chains, have not been developed until recently was the lack of a method for optimizing the parameters of the Markov model to match observed signal patterns. Such a method was proposed in the late 1960's and was immediately applied to speech processing in several research institutions. Continued refinements in the theory and implementation of Markov modelling techniques have greatly enhanced the method, leading to a wide range of applications of these models. It is the purpose of this tutorial paper to give an introduction to the theory of Markov models, and to illustrate how they have been applied to problems in speech recognition.

The Elaboration Likelihood Model of Persuasion

Richard E. Petty, John T. Cacioppo

Longitudinal data analysis using generalized linear models

Kung‐Yee Liang, Scott L. Zeger

This paper proposes an extension of generalized linear models to the analysis of longitudinal data. We introduce a class of estimating equations that give consistent estimates of the regression parameters and of their variance under mild assumptions about the time dependence. The estimating equations are derived without specifying the joint distribution of a subject's observations yet they reduce to the score equations for niultivariate Gaussian outcomes. Asymptotic theory is presented for the general class of estimators. Specific cases in which we assume independence, m-dependence and exchangeable correlation structures from each subject are discussed. Efficiency of the pioposecl estimators in two simple situations is considered. The approach is closely related to quasi-likelihood.