10,519 research outputs found
Review of \u3cem\u3eFathering at Risk\u3c/em\u3e by James R. Dudley & Glenn Stone
Photograph of John Collins' Flying Coaster - FC5 - taken Aston, 30 September 1961 close up detail of front of car. See Leeson's notebook 10, pages 81-82 for detailed notes and diagrams
Single-Father Families: A Review of the Literature
The number of children residing in single-father families in the United States quadrupled as a proportion of children\u27s living arrangements during the past few decades of the 20th century. Research on single fathers also increased and changed in nature. This article is a review of the research on single fathers and their families from the 1970s until recently, focusing on modifications in methodology and theoretical underpinnings. In general, research on single-father families evolved from qualitative studies focused on the well-being of single fathers to quantitative studies focusing on child outcomes and within-group variation among single fathers. Research also moved from descriptive studies to those testing gender and microstructural theories. This article also summarizes the main findings on single fathers and concludes with directions for future research
Concepts of Drift and Selection in “The Great Snail Debate” of the 1950s and Early 1960s
Recently, much philosophical discussion has centered on the best way to characterize the concepts of random drift and natural selection, and, in particular, on the question of whether selection and drift can be conceptually distinguished (Beatty 1984; Brandon 2005; Hodge 1983, 1987; Millstein 2002, 2005; Pfeifer 2005; Shanahan 1992; Stephens 2004). These authors all contend, to a greater or lesser degree, that their concepts make sense of biological practice. So, it should be instructive to see how the concepts of drift and selection were distinguished by the disputants in a high-profile debate; debates such as these often force biologists to take a more philosophical turn, discussing the concepts at issue in greater detail than usual. A prime candidate for just such a case study is what William Provine (1986) has termed “The Great Snail Debate,” that is, the debate over the highly polymorphic land snails Cepaea nemoralis and Cepaea hortensis in the 1950s and early 1960s. This study will reveal that much of the present-day confusion over the concepts of drift and selection is rooted in confusions of the past. Nonetheless, there are lessons that can be learned about nonadaptiveness, indiscriminate sampling, and causality with respect to these two concepts. In particular, this paper will shed light on the following questions: 1) What is “drift”? Is “drift” a purely mathematical construct, a physical process analogous to the indiscriminate sampling of balls from an urn, or the outcome of a sampling process? 2) What is “nonadaptiveness,” and is a proponent of drift committed to claims that organisms’ traits are nonadaptive? 3) Can disputes concerning selection and drift be settled by statistics alone, or is causal information essential? If causal information is essential, what does that say about the concepts of “drift” and “selection” themselves
Scientific evaluation of deterioration of historic huts of Ross Island, Antarctica
There are many challenges facing conservation of the historic
huts in Antarctica including non-biological, biological and
environmental impacts explains Professor Roberta L. Farrell,
Department of Biological Sciences, the University of Waikato. The article presents a discussion of historical huts of Ross Island, Antarctica
EMERGING TRADE PRACTICES AND TRENDS IN THE FRUIT AND VEGETABLE MARKETS
International Relations/Trade,
FUNDAMENTAL FORCES AFFECTING THE U.S. FRESH BERRY AND LETTUCE/LEAFY GREEN SUBSECTORS
Berries, Competitiveness, Fresh Produce, Leafy Greens, Lettuce, Market Forces, Porter's Five Forces, Shipper, Structural Change, Resource /Energy Economics and Policy, Q13, L10, L22, M21,
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