Research papers

The MOS 36-item short-form health survey (SF-36). I. Conceptual framework and item selection.

John E. Ware, Cathy D. Sherbourne

A 36-item short-form (SF-36) was constructed to survey health status in the Medical Outcomes Study. The SF-36 was designed for use in clinical practice and research, health policy evaluations, and general population surveys. The SF-36 includes one multi-item scale that assesses eight health concepts: 1) limitations in physical activities because of health problems; 2) limitations in social activities because of physical or emotional problems; 3) limitations in usual role activities because of physical health problems; 4) bodily pain; 5) general mental health (psychological distress and well-being); 6) limitations in usual role activities because of emotional problems; 7) vitality (energy and fatigue); and 8) general health perceptions. The survey was constructed for self-administration by persons 14 years of age and older, and for administration by a trained interviewer in person or by telephone. The history of the development of the SF-36, the origin of specific items, and the logic underlying their selection are summarized. The content and features of the SF-36 are compared with the 20-item Medical Outcomes Study short-form.

The MOS 36-ltem Short-Form Health Survey (SF-36)

John E. Ware, Cathy D. Sherbourne

A 36-item short-form (SF-36) was constructed to survey health status in the Medical Outcomes Study. The SF-36 was designed for use in clinical practice and research, health policy evaluations, and general population surveys. The SF-36 includes one multi-item scale that assesses eight health concepts: 1) limitations in physical activities because of health problems; 2) limitations in social activities because of physical or emotional problems; 3) limitations in usual role activities because of physical health problems; 4) bodily pain; 5) general mental health (psychological distress and well-being); 6) limitations in usual role activities because of emotional problems; 7) vitality (energy and fatigue); and 8) general health perceptions. The survey was constructed for self-administration by persons 14 years of age and older, and for administration by a trained interviewer in person or by telephone. The history of the development of the SF-36, the origin of specific items, and the logic underlying their selection are summarized. The content and features of the SF-36 are compared with the 20-item Medical Outcomes Study short-form.

An Introduction to the Five‐Factor Model and Its Applications

Robert R. McCrae, Oliver P. John

The five-factor model of personality is a hierarchical organization of personality traits in terms of five basic dimensions: Extraversion, Agreeableness, Conscientiousness, Neuroticism, and Openness to Experience. Research using both natural language adjectives and theoretically based personality questionnaires supports the comprehensiveness of the model and its applicability across observers and cultures. This article summarizes the history of the model and its supporting evidence; discusses conceptions of the nature of the factors; and outlines an agenda for theorizing about the origins and operation of the factors. We argue that the model should prove useful both for individual assessment and for the elucidation of a number of topics of interest to personality psychologists.

A continuum method for modeling surface tension

J. U. Brackbill, D.B. Kothe, C. Zemach

ARCH modeling in finance

Tim Bollerslev, Ray Yeutien Chou, Kenneth F. Kroner

CRC Handbook of Chemistry and Physics

Devendra Leena P

A Model of Growth Through Creative Destruction

Philippe Aghion, Peter Howitt

This paper develops a model based on Schumpeter's process of creative destruction. It departs from existing models of endogenous growth in emphasizing obsolescence of old technologies induced by the accumulation of knowledge and the resulting process or industrial innovations. This has both positive and normative implications for growth. In positive terms, the prospect of a high level of research in the future can deter research today by threatening the fruits of that research with rapid obsolescence. In normative terms, obsolescence creates a negative externality from innovations, and hence a tendency for laissez-faire economies to generate too many innovations, i.e too much growth. This business-stealing effect is partly compensated by the fact that innovations tend to be too small under laissez-faire. The model possesses a unique balanced growth equilibrium in which the log of GNP follows a random walk with drift. The size of the drift is the average growth rate of the economy and it is endogenous to the model ; in particular it depends on the size and likelihood of innovations resulting from research and also on the degree of market power available to an innovator.

Health Behavior and Health Education: Theory, Research, and Practice

Health behavior change is our greatest hope for reducing the burden of preventable disease and death around the world. Tobacco use, sedentary lifestyle, unhealthy diet, and alcohol use together account for almost one million deaths each year in the United States alone. Smoking prevalence in the United States has dropped by half since the first Surgeon General’s Report on Smoking and Health was published in 1964, but tobacco use still causes over 400,000 premature deaths each year. The World Health Organization has warned that the worldwide spread of the tobacco epidemic could claim one billion lives by the end of this century. The rising prevalence of childhood obesity could place the United States at risk of raising the first generation of children to live sicker and die younger than their parents, and the spreading epidemic of obesity among children and adults threatens staggering global health and economic tolls. The four leading behavioral risks factors and a great many others (for example, nonadherence to prescribed medical screening and prevention and disease management practices, risky sexual practices, drug use, family and gun violence, worksite and motor vehicle injuries) take disproportionate tolls in low-income and disadvantaged racial and ethnic populations, as well as in low-resource communities across the world. Addressing these behavioral risks and disparities, and the behaviors related to global health threats, such as flu pandemics, water shortages, increasingly harmful sun exposure, and the need to protect the health of the planet itself, will be critical to world health in the twenty-first century. In the past two decades since the publication of the first edition of Health Education and Health Behavior: Theory, Research, and Practice in 1990, there has been extraordinary growth in our knowledge about interventions needed to change health behaviors at both individual and population levels. This progress can be measured in the proliferation of science-based recommendations issued by authoritative evidence review panels, including the U.S. Clinical Preventive Services Task Force, the Centers for Disease Prevention and Control Task Force on Community Preventive Services, and the international Cochrane Collaboration. Today, there are evidence-based clinical practice guidelines for most major behavioral health risks, including tobacco use, unhealthy diet, sedentary lifestyle, risky drinking, and diabetes management. And there are parallel research-based guidelines for the health care system changes and policies needed to assure their delivery and use. New community practice guidelines offer additional evidence-based recommendations for a wide array of population-level school-, worksite-, and community-based programs and public policies to improve vaccination rates and physical activity levels for children and adults, improve diabetes self-management, reduce harmful sun exposure, reduce secondhand smoke exposure, prevent youth tobacco use and help adult smokers quit, reduce workplace and motor vehicle injuries, and curb drunk driving and family and gun violence.

Physics of Climate

José P. Peixóto, Abraham H. Oort

A review of our present understanding of the global climate system, consisting of the atmosphere, hydrosphere, cryosphere, lithosphere, and biosphere, and their complex interactions and feedbacks is given from the point of view of a physicist. This understanding is based both on real observations and on the results from numerical simulations. The main emphasis in this review is on the atmosphere and oceans. First, balance equations describing the large-scale climate and its evolution in time are derived from the basic thermohydrodynamic laws of classical physics. The observed atmosphere-ocean system is then described by showing how the balances of radiation, mass, angular momentum, water, and energy are maintained during present climatic conditions. Next, a hierarchy of mathematical models that successfully simulate various aspects of the climate is discussed, and examples are given of how three-dimensional general circulation models are being used to increase our understanding of the global climate machine. Finally, the possible impact of human activities on climate is discussed, with main emphasis on likely future heating due to the release of carbon dioxide in the atmosphere.

The biology of snakehead, Channa obscura (Gunther), in a Nigerian pond under monoculture

Reginald Victor, Benedicta O. Akpocha

Basics of Qualitative Research: Grounded Theory Procedures and Techniques.

Carolyn Ellis, Anselm Strauss, Juliet Corbin

Introduction Getting Started Theoretical Sensitivity The Uses of Literature Open Coding Techniques for Enhancing Theoretical Sensitivity Axial Coding Selective Coding Process The Conditional Matrix Theoretical Sampling Memos and Diagrams Writing Theses and Monographs, and Giving Talks about Your Research Criteria for Judging a Grounded Theory Study

A power primer.

Jacob Cohen

One possible reason for the continued neglect of statistical power analysis in research in the behavioral sciences is the inaccessibility of or difficulty with the standard material. A convenient, although not comprehensive, presentation of required sample sizes is provided here. Effect-size indexes and conventional values for these are given for operationally defined small, medium, and large effects. The sample sizes necessary for .80 power to detect effects at these levels are tabled for eight standard statistical tests: (a) the difference between independent means, (b) the significance of a product-moment correlation, (c) the difference between independent rs, (d) the sign test, (e) the difference between independent proportions, (f) chi-square tests for goodness of fit and contingency tables, (g) one-way analysis of variance, and (h) the significance of a multiple or multiple partial correlation.

Nonparametric Estimation from Incomplete Observations

Edward L. Kaplan, Paul Meier

Regression Models and Life-Tables

D. R. Cox

Genre Analysis: English in Academic and Research Settings

Mark O. James, John M. Swales

In recent years the concept of 'register' has been increasingly replaced by emphasis on the analysis of genre, which relates work in sociolinguistics, text linguistics and discourse analysis to the study of specialist areas of language. This book is a clear, authoritative guide to this complex area. He provides a survey of approaches to varieties of language, and considers these in relation to communication and task-based language learning. Swales outlines an approach to the analysis of genre, and then proceeds to consider examples of different genres and how they can be made accessible through genre analysis. This is important reading for all those working in teaching English for academic purposes and also of interest to those working in post-secondary writing and composition due to relevant issues in writing across the curriculum.

An introduction to out-of-plane physics

J. W. Van Orden

The objective of this paper is to provide a short introduction of some of the theoretical issues in out‐of‐plane (e,e’X) reactions. To this end, a general form of the cross section for such reactions is presented and discussed within the context of three examples of such processes.

Studies on the reproductive biology of white yam (Dioscorea rotundata Poir.)

Segnou, Christian Fatokun, M. O. Akoroda, S.K. Hahn

The theory of planned behavior

Icek Ajzen

Loss Aversion in Riskless Choice: A Reference-Dependent Model

Amos Tversky, Daniel Kahneman

Much experimental evidence indicates that choice depends on the status quo or reference level: changes of reference point often lead to reversals of preference. We present a reference-dependent theory of consumer choice, which explains such effects by a deformation of indifference curves about the reference point. The central assumption of the theory is that losses and disadvantages have greater impact on preferences than gains and advantages. Implications of loss aversion for economic behavior are considered.

A low-cost, high-efficiency solar cell based on dye-sensitized colloidal TiO2 films

Brian C. O’Regan, Michaël Grätzel

Methods for Dietary Fiber, Neutral Detergent Fiber, and Nonstarch Polysaccharides in Relation to Animal Nutrition

P.J. Van Soest, James B. Robertson, B.A. Lewis

There is a need to standardize the NDF procedure. Procedures have varied because of the use of different amylases in attempts to remove starch interference. The original Bacillus subtilis enzyme Type IIIA (XIA) no longer is available and has been replaced by a less effective enzyme. For fiber work, a new enzyme has received AOAC approval and is rapidly displacing other amylases in analytical work. This enzyme is available from Sigma (Number A3306; Sigma Chemical Co., St. Louis, MO). The original publications for NDF and ADF (43, 53) and the Agricultural Handbook 379 (14) are obsolete and of historical interest only. Up to date procedures should be followed. Triethylene glycol has replaced 2-ethoxyethanol because of reported toxicity. Considerable development in regard to fiber methods has occurred over the past 5 yr because of a redefinition of dietary fiber for man and monogastric animals that includes lignin and all polysaccharides resistant to mammalian digestive enzymes. In addition to NDF, new improved methods for total dietary fiber and nonstarch polysaccharides including pectin and beta-glucans now are available. The latter are also of interest in rumen fermentation. Unlike starch, their fermentations are like that of cellulose but faster and yield no lactic acid. Physical and biological properties of carbohydrate fractions are more important than their intrinsic composition.

Concrete Mathematics: A Foundation for Computer Science.

Edward A. Bender, Ronald Graham, Donald E. Knuth, Oren Patashnik

Molecular Biology of Prion Diseases

Stanley B. Prusiner

Prions cause transmissible and genetic neurodegenerative diseases, including scrapie and bovine spongiform encephalopathy of animals and Creutzfeldt-Jakob and Gerstmann-Sträussler-Scheinker diseases of humans. Infectious prion particles are composed largely, if not entirely, of an abnormal isoform of the prion protein, which is encoded by a chromosomal gene. A posttranslational process, as yet unidentified, converts the cellular prion protein into an abnormal isoform. Scrapie incubation times, neuropathology, and prion synthesis in transgenic mice are controlled by the prion protein gene. Point mutations in the prion protein genes of animals and humans are genetically linked to development of neuro-degeneration. Transgenic mice expressing mutant prion proteins spontaneously develop neurologic dysfunction and spongiform neuropathology. Understanding prion diseases may advance investigations of other neurodegenerative disorders and of the processes by which neurons differentiate, function for decades, and then grow senescent.

The Comparative Method in Evolutionary Biology

Paul Harvey, Mark Pagel

Abstract From Darwin onward, it has been second nature for evolutionary biologists to think comparatively because comparisons establish the generality of evolutionary phenomena. Do large genomes slow down development? What lifestyles select for large brains? Are extinction rates related to body size? These are all questions for the comparative method, and this book is about how such questions can be answered. The first chapter elaborates on suitable questions for the comparative approach and shows how it complements other approaches to problem-solving in evolution. The second chapter identifies the biological causes of similarity among closely related species for almost any observed character. The third chapter discusses methods for reconstructing phylogenetic trees and ancestral character states. The fourth chapter sets out to develop statistical tests that will determine whether different characters that exist in discrete states show evidence for correlated evolution. Chapter 5 turns to comparative analyses of continuously varying characters. Chapter 6 looks at allometry to exemplify the themes and methods discussed earlier, while the last chapter looks to future development of the comparative approach in both molecular and organismic biology.