Research papers

Molecular Cell Biology

Harvey F. Lodish

Molecular cell biology , Molecular cell biology , مرکز فناوری اطلاعات و اطلاع رسانی کشاورزی

A Conceptual Model of Service Quality and Its Implications for Future Research

A. Parasuraman, Valarie A. Zeithaml, Leonard L. Berry

The attainment of quality in products and services has become a pivotal concern of the 1980s. While quality in tangible goods has been described and measured by marketers, quality in services is largely undefined and unresearched. The authors attempt to rectify this situation by reporting the insights obtained in an extensive exploratory investigation of quality in four service businesses and by developing a model of service quality. Propositions and recommendations to stimulate future research about service quality are offered.

Electron transfers in chemistry and biology

R. A. Marcus, Norman Sutin

CONFIDENCE LIMITS ON PHYLOGENIES: AN APPROACH USING THE BOOTSTRAP

Joseph Felsenstein

The recently-developed statistical method known as the "bootstrap" can be used to place confidence intervals on phylogenies. It involves resampling points from one's own data, with replacement, to create a series of bootstrap samples of the same size as the original data. Each of these is analyzed, and the variation among the resulting estimates taken to indicate the size of the error involved in making estimates from the original data. In the case of phylogenies, it is argued that the proper method of resampling is to keep all of the original species while sampling characters with replacement, under the assumption that the characters have been independently drawn by the systematist and have evolved independently. Majority-rule consensus trees can be used to construct a phylogeny showing all of the inferred monophyletic groups that occurred in a majority of the bootstrap samples. If a group shows up 95% of the time or more, the evidence for it is taken to be statistically significant. Existing computer programs can be used to analyze different bootstrap samples by using weights on the characters, the weight of a character being how many times it was drawn in bootstrap sampling. When all characters are perfectly compatible, as envisioned by Hennig, bootstrap sampling becomes unnecessary; the bootstrap method would show significant evidence for a group if it is defined by three or more characters.

The Biology and Behaviour of Cicadulina triangula in Relation to Maize Streak Virus Resistance Screening

Z. T. Dąbrowski

Intrinsic Motivation and Self-Determination in Human Behavior

Edward L. Deci, Richard M. Ryan

Naturalistic inquiry

Yvonna S. Lincoln, Egon G. Guba, Joseph J. Pilotta

A Conceptual Model of Service Quality and Its Implications for Future Research

A. Parasuraman, Valarie A. Zeithaml, Leonard L. Berry

The attainment of quality in products and services has become a pivotal concern of the 1980s. While quality in tangible goods has been described and measured by marketers, quality in services is largely undefined and unresearched. The authors attempt to rectify this situation by reporting the insights obtained in an extensive exploratory investigation of quality in four service businesses and by developing a model of service quality. Propositions and recommendations to stimulate future research about service quality are offered.

Free radicals in biology and medicine

Barry Halliwell, John M.C. Gutteridge

The search for supersymmetry: Probing physics beyond the standard model

Howard E. Haber

Materials Science and Engineering: An Introduction

William D. Callister

List of Symbols.Introduction.Atomic Structure and Interatomic Bonding.The Structure of Crystalline Solids.Imperfections in Solids.Diffusion.Mechanical Properties of Metals.Dislocations and Strengthening Mechanisms.Failure.Phase Diagrams.Phase Transformations in Metals: Development of Microstructure and Alteration of Mechanical Properties.Thermal Processing of Metal Alloys.Metals Alloys.Structures and Properties of Ceramics.Applications and Processing of Ceramics.Polymer Structures.Characteristics, Applications, and Processing of Polymers.Composites.Corrosion and Degradation of Materials.Electrical Properties.Thermal Properties.Magnetic Properties.Optical Properties.Materials Selection and Design Considerations.Economic, Environmental, and Societal Issues in Materials Science and Engineering.Appendix A: The International System of Units (SI).Appendix B: Properties of Selected Engineering Materials.Appendix C: Costs and Relative Costs for Selected Engineering Materials.Appendix D: Mer Structures for Common Polymers.Appendix E: Glass Transition and Melting Temperatues for Common Polymeric Materials.Glossary.Answers to Selected Problems.Index.

FROM NOVICE TO EXPERT EXCELLENCE AND POWER IN CLINICAL NURSING PRACTICE

Patricia Benner

1. Uncovering the Knowledge Embedded in Clinical Nursing Practice. 2. The Dreyfus Model of Skill Acquisition Applied to Nursing. 3. An Interpretive Approach to Identifying and Describing Clinical Knowledge. 4. The Helping Role. 5. The Teaching-Coaching Function. 6. The Diagnostic and Monitoring Function. 7. Effective Management of Rapidly Changing Situations. 8. Administering and Monitoring Therapeutic Interventions and Regimens. 9. Monitoring and Ensuring the Quality of Health Care Practices. 10. Organizational and Work-Role Competencies. 11. Implications for Research and Clinical Practice. 12. Implications for Career Development and Education. 13. The Quest for a New Identity and New Entitlement in Nursing. 14. Excellence and Power in Clinical Nursing Practice. Epilogue: Practical Applications. References. Glossary. Appendix. Index.

A qualitative physics based on confluences

Johan de Kleer, John Seely Brown

In search of a more effective interaction pattern in biology laboratories

Peter Akinsola Okebukola

The development of scientific process skills is central to laboratory work in biology. A search for the laboratory interaction pattern that is most potent in the development of these skills is described. 720 secondary class three biology students were involved in a pre-test, treatment, post-test experiment in which competitive interaction was found to be superior to cooperative and individualistic interaction patterns in promoting the development of process/laboratory skills.

Supercollider physics

E. Eichten, I. Hinchliffe, Kenneth Lane, Chris Quigg

Eichten et al. summarize the motivation for exploring the 1-TeV (=${10}^{12}$ eV) energy scale in elementary particle interactions and explore the capabilities of proton-(anti)proton colliders with beam energies between 1 and 50 TeV. The authors calculate the production rates and characteristics for a number of conventional processes, and discuss their intrinsic physics interest as well as their role as backgrounds to more exotic phenomena. The authors review the theoretical motivation and expected signatures for several new phenomena which may occur on the 1-TeV scale. Their results provide a reference point for the choice of machine parameters and for experiment design.

Some Models for Estimating Technical and Scale Inefficiencies in Data Envelopment Analysis

Rajiv D. Banker, A. Charnes, W. W. Cooper

In management contexts, mathematical programming is usually used to evaluate a collection of possible alternative courses of action en route to selecting one which is best. In this capacity, mathematical programming serves as a planning aid to management. Data Envelopment Analysis reverses this role and employs mathematical programming to obtain ex post facto evaluations of the relative efficiency of management accomplishments, however they may have been planned or executed. Mathematical programming is thereby extended for use as a tool for control and evaluation of past accomplishments as well as a tool to aid in planning future activities. The CCR ratio form introduced by Charnes, Cooper and Rhodes, as part of their Data Envelopment Analysis approach, comprehends both technical and scale inefficiencies via the optimal value of the ratio form, as obtained directly from the data without requiring a priori specification of weights and/or explicit delineation of assumed functional forms of relations between inputs and outputs. A separation into technical and scale efficiencies is accomplished by the methods developed in this paper without altering the latter conditions for use of DEA directly on observational data. Technical inefficiencies are identified with failures to achieve best possible output levels and/or usage of excessive amounts of inputs. Methods for identifying and correcting the magnitudes of these inefficiencies, as supplied in prior work, are illustrated. In the present paper, a new separate variable is introduced which makes it possible to determine whether operations were conducted in regions of increasing, constant or decreasing returns to scale (in multiple input and multiple output situations). The results are discussed and related not only to classical (single output) economics but also to more modern versions of economics which are identified with “contestable market theories.”

Science, industry, and the social order in Mulhouse, 1798–1871

Robert Fox

There is a story, which historians of modern France often tell, of the ministerial official in Paris who had only to glance at his clock in order to know the exact passage of Vergil being construed and the law of physics being expounded in every school throughout the country. Invariably, the story is told for a purpose. It is used to demonstrate the high degree of centralization and the attendant rigidity of the French educational system, usually with special reference to the nineteenth century. The story, which has its roots in the rich corpus of Napoleonic legend, serves this purpose very well, but unfortunately it is both apocryphal and misleading. For while it is true that most nineteenth-century ministers with responsibility for education aspired to the ideal of total control, not one of them came close to it in reality.

A resource‐based view of the firm

Birger Wernerfelt

Abstract The paper explores the usefulness of analysing firms from the resource side rather than from the product side. In analogy to entry barriers and growth‐share matrices, the concepts of resource position barrier and resource‐product matrices are suggested. These tools are then used to highlight the new strategic options which naturally emerge from the resource perspective.

Toward a Model of Organizations as Interpretation Systems

Richard L. Daft, Karl E. Weick

A comparative model of organizations as interpretation systems is proposed. The model describes four interpretation modes: enacting,discovering, undirected viewing, and conditioned viewing. Each mode is determined by (1) management’s beliefs about the environment and (2)organizational intrusiveness. Interpretation modes are hypothesized to be associated with organizational differences in environmental scanning,equivocality reduction, strategy, and decision making.

The Health Belief Model: A Decade Later

Nancy K. Janz, Marshall H. Becker

Since the last comprehensive review in 1974, the Health Belief Model (HBM) has continued to be the focus of considerable theoretical and research attention. This article presents a critical review of 29 HBM-related investigations published during the period of 1974-1984, tabulates the findings from 17 studies conducted prior to 1974, and provides a summary of the total 46 HBM studies (18 prospective, 28 retrospective). Twenty-four studies examined preventive-health behaviors (PHB), 19 explored sick-role behaviors (SRB), and three addressed clinic utilization. A "significance ratio" was constructed which divides the number of positive, statistically-significant findings for an HBM dimension by the total number of studies reporting significance levels for that dimension. Summary results provide substantial empirical support for the HBM, with findings from prospective studies at least as favorable as those obtained from retrospective research. "Perceived barriers" proved to be the most powerful of the HBM dimensions across the various study designs and behaviors. While both were important overall, "perceived susceptibility" was a stronger contributor to understanding PHB than SRB, while the reverse was true for "perceived benefits." "Perceived severity" produced the lowest overall significance ratios; however, while only weakly associated with PHB, this dimension was strongly related to SRB. On the basis of the evidence compiled, it is recommended that consideration of HBM dimensions be a part of health education programming. Suggestions are offered for further research.

Low-temperature physics: Persistent currents in liquid 3He

P. V. E. McClintock

Introduction to Plasma Physics and Controlled Fusion

Francis F. Chen

How the Laws of Physics Lie

Nancy Cartwright

Nancy Cartwright argues for a novel conception of the role of fundamental scientific laws in modern natural science. If we attend closely to the manner in which theoretical laws figure in the practice of science, we see that despite their great explanatory power these laws do not describe reality. Instead, fundamental laws describe highly idealized objects in models. Thus, the correct account of explanation in science is not the traditional covering law view, but the ‘simulacrum’ account. On this view, explanation is a matter of constructing a model that may employ, but need not be consistent with, a theoretical framework, in which phenomenological laws that are true of the empirical case in question can be derived. Anti‐realism about theoretical laws does not, however, commit one to anti‐realism about theoretical entities. Belief in theoretical entities can be grounded in well‐tested localized causal claims about concrete physical processes, sometimes now called ‘entity realism’. Such causal claims provide the basis for partial realism and they are ineliminable from the practice of explanation and intervention in nature.

A Global Measure of Perceived Stress

Sheldon Cohen, Tom Kamarck, Robin Mermelstein

This paper presents evidence from three samples, two of college students and one of participants in a community smoking-cessation program, for the reliability and validity of a 14-item instrument, the Perceived Stress Scale (PSS), designed to measure the degree to which situations in one's life are appraised as stressful. The PSS showed adequate reliability and, as predicted, was correlated with life-event scores, depressive and physical symptomatology, utilization of health services, social anxiety, and smoking-reduction maintenance. In all comparisons, the PSS was a better predictor of the outcome in question than were life-event scores. When compared to a depressive symptomatology scale, the PSS was found to measure a different and independently predictive construct. Additional data indicate adequate reliability and validity of a four-item version of the PSS for telephone interviews. The PSS is suggested for examining the role of nonspecific appraised stress in the etiology of disease and behavioral disorders and as an outcome measure of experienced levels of stress.