Birth wantedness reports: a look forward and a look back

A number of checks can be done to assess reliability of attitudinal data pertaining to fertility. We ascertain how births that would be considered unintended, based on Time 1 reports of fertility intentions, are classified by respondents at a second interview after the birth occurred. The 1988 National Survey of Family Growth and a telephone reinterview allow us to identify respondents who initially intended to postpone or stop childbearing, but who then had a birth, and to analyze the reports they gave of the wantedness of the pregnancy leading to the birth. We also examine wantedness responses of women who claimed in 1988 that they intended to conceive within the next few years. Reports are compared across a range of respondent characteristics and circumstances, including changes in marital status since the initial interview. The analysis reveals nontrivial inconsistency between women's stated birth intentions and their reports about the wantedness of subsequent births. Details across subgroups are examined. Results also provide new information about effects of duration since birth on intention reports.     

Birth wantedness reports: A look forward and a look back

Abstract

The majority of research indicates that estimates of heritability are not generalizable beyond the specific sample on which they have been calculated. This research has been limited, however, in its scope. The present set of investigations center upon an examination of previously reported heritability estimates for the scales of the Minnesota Multiphasic Personality Inventory (MMPI). The first investigation correlates the estimates for eight samples derived from a variety of published studies. The second investigation correlates the DZ twin pair and MZ twin pair intraclass correlations from four of the first investigation's samples. The third investigation correlates the estimates from one study in which the same sample was tested twice over a period of less than five years. It is concluded that no evidence is available for the generalizability of these estimates of MMPI scale heritability either across samples or even across time with the same sample.     

Reactive oxygen species and protein oxidation in aging: a look back, a look ahead.

The existence of free radicals, as chemical entities, was inferred 100 years ago but not universally accepted for some 30-40 years. The existence and importance of free radicals in biological systems was not recognized until the mid 1950s, by a small number of visionary scientists who can be credited with founding the field of reactive oxygen biochemistry. For most of the remaining 20th century, reactive oxygen species (ROS) were considered a type of biochemical "rusting agent" that caused stochastic tissue damage and disease. As we enter the 21st century, reactive oxygen biochemistry is maturing as a discipline and establishing its importance among the biomedical sciences. It is now recognized that virtually every disease state involves some degree of oxidative stress. Moreover, we are now beginning to recognize that ROS are produced in a well-regulated manner to help maintain homeostasis on the cellular level in normal, healthy tissue. This review summarizes the history of reactive oxygen biochemistry, outlining major paradigm shifts that the field has undergone and continues to experience. The contributions of Earl Stadtman to the recent history of the field (1980-present) are especially highlighted. The role of ROS in signal transduction is presented in some detail as central to the latest paradigm shift. Emerging technologies, particularly proteomic technologies, are discussed that will facilitate further evolution in the field of reactive oxygen biochemistry.     

Neurotransmitter enzyme and receptor regulation: A look back

1. This report is a tribute to Dr. Julius Axelrod, in whose laboratory the author worked as a research associate from 1971-1974. 2. Work on the regulation of dopamine beta-hydroxylase and phenylethanolamine N-methyl transferase is reviewed, particularly studies showing how transynaptic and hormonal factors regulate enzyme synthesis and degradation respectively. 3. Work taking place in the author's laboratory is reviewed with respect to the influence Dr. Axelrod had on the author and his subsequent work.     

The modified Q-cycle: A look back at its development and forward to a functional model

On looking back at a lifetime of research, it is interesting to see, in the light of current progress, how things came to be, and to speculate on how things might be. I am delighted in the context of the Mitchell prize to have that excuse to present this necessarily personal view of developments in areas of my interests. I have focused on the Q-cycle and a few examples showing wider ramifications, since that had been the main interest of the lab in the 20 years since structures became available, - a watershed event in determining our molecular perspective. I have reviewed the evidence for our model for the mechanism of the first electron transfer of the bifurcated reaction at the Q_o-site, which I think is compelling. In reviewing progress in understanding the second electron transfer, I have revisited some controversies to justify important conclusions which appear, from the literature, not to have been taken seriously. I hope this does not come over as nitpicking. The conclusions are important to the final section in which I develop an internally consistent mechanism for turnovers of the complex leading to a state similar to that observed in recent rapid-mix/freeze-quench experiments, reported three years ago. The final model is necessarily speculative but is open to test.     

Cell physiology at the Mount Desert Island Biological Laboratory: a brief look back and forward

The Mount Desert Island Biological Laboratory (MDIBL) has played important roles in the development of modern physiological concepts and tools, particularly in the fields of kidney and epithelial cell physiology. Over the last decade, MDIBL has undergone remarkable growth and evolution. This article will briefly review MDIBL's past and outline its future directions. It is hoped that this overview will renew and stimulate interest in MDIBL and, in particular, will encourage an even wider community of physiologists to participate in its ongoing growth and development.     

Modern analytical ultracentrifugation in protein science: look forward, not back

The reasons for replacing the classical strictly two-component velocity and equilibrium analytical ultracentrifugation Svedberg equations by multicomponent equations, applicable in the study of biological macromolecular systems, are given.