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1.
James R. Griesemer 《Biology & philosophy》1990,5(1):3-36
Accounts of the relation between theories and models in biology concentrate on mathematical models. In this paper I consider
the dual role of models as representations of natural systems and as a material basis for theorizing. In order to explicate
the dual role, I develop the concept of a remnant model, a material entity made from parts of the natural system(s) under
study. I present a case study of an important but neglected naturalist, Joseph Grinnell, to illustrate the extent to which
mundane practices in a museum setting constitute theorizing. I speculate that historical and sociological analyses of institutions
can play a specific role in the philosophical analysis of model-building strategies. 相似文献
2.
This editorial highlights a study by Rodriguez, Sanchez‐Moran et al. (2019) in the current issue of the Journal of Neurochemistry, in which the authors describe a microcephalic boy carrying the novel heterozygous de novo missense mutation c.560A> G; p.Asp187Gly in Cdh1/Fzr1 encoding the APC/C E3‐ubiquitin ligase cofactor CDH1. A functional characterization of mutant APC/CCDH1 confirms an aberrant division of neural progenitor cells, a condition known to determine the mouse brain cortex size. These data suggest that APC/CCDH1 may contribute to the regulation of the human brain size.
3.
Spinocerebellar ataxia type-3 or Machado-Joseph disease (SCA3/MJD) is an autosomal dominant neurodegenerative disease caused by triplet nucleotide expansion. The expansion of the polyglutamine tract near the C terminus of the MJD1 gene product, ataxin-3, above a threshold of 40 glutamine repeats causes neuronal loss and degeneration. The expanded ataxin-3 forms aggregates, and nuclear inclusions, within neurons, possibly due to the misfolding of mutant proteins. Here we report upon the behavioral test changes related to truncated and expanded forms of MJD protein (MJDtr) in Drosophila, and show that expanded MJDtr, when expressed in the nervous system, causes characteristic locomotor dysfunction and anosmia. This phenomenon has not been previously reported in humans or in transgenic Drosophila models. In addition, the in vivo expression of the antiapoptotic gene bcl-2 showed no evidence of ameliorating the deleterious effect of MJDtr-Q78s, either in the eye or in the nervous system. The study shows that such Drosophila transgenic models express olfactory dysfunction and ataxic behavior as observed in human patients. 相似文献
4.
Joliot P 《Photosynthesis research》2003,76(1-3):65-72
In this minireview, the earlier researches that led to the discovery of the period-four oscillations of the flash-induced
oxygen formation are presented. It also includes the background of the classical model proposed by Bessel Kok, in which the
formation of oxygen requires the sequential accumulation of four positive charges on the donor side of the same reaction center.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
5.
Johnson CN 《Journal of the history of biology》2007,40(3):529-556
Almost any modern reader’s first encounter with Darwin’s writing is likely to be the “Historical Sketch,” inserted by Darwin
as a preface to an early edition of the Origin of Species, and having since then appeared as the preface to every edition after the second English edition. The Sketch was intended
by him to serve as a short “history of opinion” on the species question before he presented his own theory in the Origin proper. But the provenance of the “Historical Sketch” is somewhat obscure. Some things are known about its production, such
as when it first appeared and what changes were made to it between its first appearance in 1860 and its final form, for the
fourth English edition, in 1866. But how it evolved in Darwin’s mind, why he wrote it at all, and what he thought he was accomplishing
by prefacing it to the Origin remain questions that have not been carefully addressed in the scholarly literature on Darwin. I attempt to show that Darwin’s
various statements about the “Historical Sketch,” made primarily to several of his correspondents between 1856 and 1860, are
somewhat in conflict with one another, thus making problematic a satisfactory interpretation of how, when, and why the Sketch
came to be. I also suggest some probable resolutions to the several difficulties.
How Darwin came to settle on the title “Historical Sketch” for the Preface to the Origin is not certain, but a guess may be ventured. When he first submitted the text to Asa Gray in February 1860 he called it simply
“Preface Contributed by the Author to this American Edition” (Burkhardt et al., eds., vol. 8, 1993, p. 572; the collected
correspondence is hereafter cited as CCD). In fact he had thought of it as being properly called a Preface much earlier, perhaps as early as 1856, as will be seen
in what follows. It came to be called “An Historical Sketch of the Recent Progress of Opinion on the Origin of Species” only
in the third English edition, April 1861. This is the title it retained thereafter, with the exception of an addition to the
title in the sixth English edition, “Previously to the Publication of the First Edition of this Work” (Peckham, 1959, pp. 20, 59). The word “sketch,” on the other hand was one of two words Darwin commonly used in private correspondence to
refer to the book that would later become the Origin, the other word being “Abstract,” and both signifying that Darwin thought of the work as being a resume rather than a full-fledged
study (e.g., letter to J.D. Hooker, May 9 1856, CCD vol. 6 p. 106; letter to Baden Powell January 18 1860, CCD vol. 8 p. 41; letter to Lyell 25 June 1858, CCD v. 7, 1991, pp. 117–8; letter to Lyell May 1856, CCD, v. 6 p. 100). The most likely source of the title “Historical Sketch” for Darwin’s Preface is Charles Lyell’s Principles of Geology in which, beginning with the third edition (1834), Lyell added titles to his chapters, calling chapters 2–4 “Historical Sketch
of the Progress of Geology” (Secord, in Lyell [1997], p. xlvii; for other uses by Lyell of this expression, cf. Porter, 1976, p. 95; idem 1982, p. 38; and Lyell, 1830 [1990], p. 30). Further parallels between Lyell’s Introduction and Darwin’s “Historical Sketch” in terms of content and strategy
are suggested below. 相似文献
6.
David J.MABBERLEY 《植物分类与资源学报》2011,33(1):31-38
The history of botanic gardens in the United Kingdom is sketched out with particular reference to the Royal Botanic Gardens Kew and its changing role to meet societal requirements over 250 years.Kew’s position as a modern scientific institution confronting today’s environmental issues through its Breathing Planet Programme yet retaining its heritage buildings and collections is pinpointed. 相似文献
7.
8.
André Franz Leena Ackermann Thorsten Hoppe 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》2014
The AAA-ATPase Cdc48 (also called p97 or VCP) acts as a key regulator in proteolytic pathways, coordinating recruitment and targeting of substrate proteins to the 26S proteasome or lysosomal degradation. However, in contrast to the well-known function in ubiquitin-dependent cellular processes, the physiological relevance of Cdc48 in organismic development and maintenance of protein homeostasis is less understood. Therefore, studies on multicellular model organisms help to decipher how Cdc48-dependent proteolysis is regulated in time and space to meet developmental requirements. Given the importance of developmental regulation and tissue maintenance, defects in Cdc48 activity have been linked to several human pathologies including protein aggregation diseases. Thus, addressing the underlying disease mechanisms not only contributes to our understanding on the organism-wide function of Cdc48 but also facilitates the design of specific medical therapies. In this review, we will portray the role of Cdc48 in the context of multicellular organisms, pointing out its importance for developmental processes, tissue surveillance, and disease prevention. This article is part of a Special Issue entitled: Ubiquitin–Proteasome System. Guest Editors: Thomas Sommer and Dieter H. Wolf. 相似文献
9.
Half of each ovary of seven rabbits was removed and deep-frozen in liquid nitrogen for two to three months before being thawed and reimplanted in the original animal. Three of the animals with cryopreserved demi-ovaries bred but did not conceive and these three plus one other had surviving ovarian tissue and normal uterine morphology at autopsy. In one of these cases the ovaries were smooth surfaced but, in two animals, follicles were present, and, in one, corpora haemoragica were observed. The three remaining rabbits would not breed after their frozen-thawed demi-ovaries were reimplanted and their uteri were atrophied at autopsy. No surviving ovarian tissue was detected. In the four cases where the organs survived cryopreservation, three sets of demi-ovaries were fast-frozen by a series of three plunges, respectively, into alcohol baths at ?7° C and ?38° C and then into liquid nitrogen at ?196° C. The fourth set was frozen at slower rates of 1° C per minute to ?7° C and then at 0.3° C per minute to ?38° C before being plunged into liquid nitrogen. One set of demi-ovaries was intact and the other three had the medulla cored out before freezing.We conclude that several protocols suffice to deep-freeze rabbit ovaries and permit the organs to return to partial function when reimplanted. 相似文献
10.
Blood luteinizing hormone (LH) and testosterone levels are lower in old than in young male rats. The specific opiate antagonist, naloxone, previously shown to increase serum LH in mature male rats, exhibited relatively little ability to raise serum LH and testosterone levels in old (18–20 mo) as compared to young (4–5 mo) male rats. The brain opiate, met5-enkephalin, which depresses LH, was found to be significantly higher in the hypothalamus of old than of young male rats. These observations suggest that hypothalamic opiates may be partially responsible for the lower serum LH and testosterone levels in old male rats, and for reduced release of these hormones in response to naloxone administration. 相似文献