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1.
This essay examines the curious relationship between Charles Darwin and the palaeontologist William Boyd Dawkins (1837–1929). Dawkins was a beneficiary of Darwin's patronage and styled himself as a Darwinian to Darwin and the public, yet viciously attacked Darwin and his theory in anonymous reviews. This has confused historians who have misunderstood the exact nature of Dawkins's attitude towards evolution and his relationship to Darwin. The present study explains both the reasons for Dawkins's contradictory statements and his relationship with Darwin. I introduce Batesian mimicry as a conceptual framework to make sense of Dawkins's actions, suggesting that Dawkins mimicked a Darwinian persona in order to secure advancement in the world of Victorian science. Dawkins's pro-Darwinian stance, therefore, was a façade, an act of mimicry. I argue that Dawkins exploited Darwin for his patronage – which took the form of advice, support from Darwin's well-placed friends, and monetary assistance – while safely expressing his dissent from Darwinian orthodoxy in the form of anonymous reviews. This is, therefore, a case study in how scientific authority and power could be gained and maintained in Victorian science by professing allegiance to Darwin and Darwinism.  相似文献   

2.
History has been disparaged since the late 19th century for not conforming to norms of scientific explanation. Nonetheless, as a matter of fact a work of history upends the regnant philosophical conception of science in the second part of the 20th century. Yet despite its impact, Kuhn’s Structure has failed to motivate philosophers to ponder why works of history should be capable of exerting rational influence on an understanding of philosophy of science. But all this constitutes a great irony and a mystery. The mystery consists of the persistence of a complete lack of interest in efforts to theorize historical explanation. Fundamental questions regarding why an historical account could have any rational influence remain not merely unanswered, but unasked. The irony arises from the fact that analytic philosophy of history went into an eclipse where it remains until this day just around the time that the influence of Kuhn’s great work began to make itself felt. This paper highlights puzzles long ignored regarding the challenges a work of history managed to pose to the epistemic authority of science, and what this might imply generally for the place of philosophy of history vis-à-vis the problems of philosophy.  相似文献   

3.
This paper discusses the historiography of the ‘two cultures’ controversy. C. P. Snow’s lament about the ‘two cultures’, literary and scientific, has inspired a wide range of comment—much of which begins by citing Snow and his thesis, before going on to discuss very different things. This paper focuses upon one strand of this commentary, the historical analysis of the controversy itself. A ‘historical’ analysis is defined here as one that resists the impulse to enter the argument on behalf of Snow or Leavis, to conceive of their argument in the terms that Snow defined, or to invoke their argument as a precursor to some contemporary issue. Instead, a historical interpretation registers distance between that day and this, takes the controversy itself as its object of study, and explores the tensions and associations that came to be packed into those now familiar terms. As the fiftieth anniversary of Snow’s Rede Lecture nears, this approach—rather than the repetition of clichés about the bridging of cultures—offers both analytical perspective on the controversy and interpretive possibilities for its examination.  相似文献   

4.
In the eighteenth century, the historiography of astronomy was part of a wider discussion concerning the history of the human spirit. The concept of the human spirit was very popular among Enlightenment authors because it gave the history of human knowledge continuity, unity and meaning. Using this concept, scientists and historians of science such as Montucla, Lalande, Bailly and Laplace could present the history of astronomy in terms of a progress towards contemporary science that was slow and could be interrupted at times, but was still constant, regular, and necessary. In my paper I intend to explain how the originally philosophical concept of the human spirit was transferred to the history of astronomy. I also introduce the basic principles to which the development of the spirit is subject in astronomy, according to historians of astronomy. The third part of the paper describes how historians of astronomy took into account the effect of social and natural factors on the history of astronomy.  相似文献   

5.
The nuclear lamins polymerize to form the nuclear lamina, a fibrous structure found on the inner face of the nuclear membrane. The lamins also appear to form structures within the nucleoplasm. These various lamin structures help to establish and maintain the shape and strength of the interphase nucleus, but recent work also suggests that the lamins have a role in nuclear processes such as DNA replication. Furthermore, mutations in the human lamin A/C gene have recently been linked to several diseases, including Emery-Dreifuss muscular dystrophy. This review discusses the nature of these mutations and the possible effects of lamin mutations on nuclear function.  相似文献   

6.
Construction of causally and structurally adequate simultaneous equations models can be accomplished by determining causal relations between potential variables and balancing these statistically derived inferences with economic theory to relate behavioural or technological forces among the variables. An appropriate lag structure for each of the equations can be determined by a two step multiple transfer function approach involving reduced form equations. Testing the specification of already existing simultaneous equations models is done by constructing multiple transfer function models of the reduced form equations of the simultaneous equations models which permit incorporation of lead cross correlations.  相似文献   

7.
A survey of the major fossiliferous amber deposits is provided, including ages and various categories of life forms reported from each. The frequence of occurrence of the major groups of plants and animals in these amber deposits is also given. Thus far, DNA from four insect and one plant species has been extracted from amber fossils. In the case of the stingless bee in Dominican amber, evidence of reproducibility is provided, since two independent laboratories isolated DNA from six or more different specimens of the same insect.Amber sources for DNA studies are listed together with their advantages and disadvantages. The important points are the availability of desired pieces, the proper identification of the fossil, verification of the amber deposit, the cost involved, and the feasibility of causing damage to the specimen. The availability of several types of amber (Mexican, Dominican, Baltic, Chinese, Canadian, Siberian and Lebanese) at four major sources (academic collections, commercial dealers, private collections and amber mines) is discussed. The scientific implications of obtaining DNA from amber inclusions are presented.  相似文献   

8.
This paper examines the meanings of the daguerreotype for the astronomer and physicist who introduced it to the world, François Arago. The regime of knowledge production which held sway at the birth of photography implied an alternative view of the moral and political implications of machines from that usually suggested by discussions of ‘mechanization’. Instead of celebrating detachment, instantaneity, transparency and abstraction, Arago understood instruments and human citizens as dynamic mediators which necessarily modify the forces they transmit. His moral economy of instruments also implied specific aesthetic and political commitments. Arago’s republican convictions and expressive personal style, as well as his identification with revolutionary scientist-statesmen including Lazare Carnot and Condorcet, present a strong contrast with the imperial science of Laplace and the image of disengaged, impersonal ‘mechanism’ often associated with the physical science of this time.  相似文献   

9.
The objective of this study is to discuss the potential impact of a global warming on various aspects of human health. Changes in heat-related mortality are estimated for four countries: the United States, Canada, the People's Republic of China and Egypt. In addition, the potential confounding impact of increased air pollution is considered. Finally, a framework to analyze two vector-borne diseases, onchocerciasis and malaria, which may spread if temperatures increase, is discussed. Our findings suggest that heat-related mortality is estimated to rise significantly in all four countries if the earth warms, with the greatest impacts in China and Egypt. The most sensitive areas are those with intense but irregular heat waves. In the United States, air pollution does not appear to impact daily mortality significantly when severe weather is present, although it seems to have a slight influence when weather conditions are not stressful.  相似文献   

10.
This paper defends the right of historians to make use of their knowledge of the remote consequences of past actions. In particular, it is argued that the disciplinary cohesion of the history of science relies crucially upon our ability to target, for further investigation, those past activities ancestral to modern science. The history of science is not limited to the study of those activities but it is structured around them. In this sense, the discipline is inherently ‘present-centred’: its boundaries are determined, in part, by judgements inaccessible to the historical actors. Present-centredness of this sort, it is urged, should not be regarded as a problem; its methodological consequences are minimal.  相似文献   

11.
Cannabinoids represent one of the most widely used hallucinogenic drugs and induce profound alterations in sensory perception and emotional processing. Similarly, the dopamine (DA) neurotransmitter system is critical for the central processing of emotion and motivation. Functional disturbances in either of these neurotransmitter systems are well-established correlates of the psychopathological symptoms and behavioral manifestations observed in addiction and schizophrenia. Increasing evidence from the anatomical, pharmacological and behavioral neuroscience fields points to complex functional interactions between these receptor systems at the anatomical, pharmacological and neural systems levels. An important question relates to whether these systems act in an orchestrated manner to produce the emotional processing and sensory perception deficits underlying addiction and schizophrenia. This review describes evidence for functional neural interactions between cannabinoid and DA receptor systems and how disturbances in this neural circuitry may underlie the aberrant emotional learning and processing observed in disorders such as addiction and schizophrenia. Received 20 January 2006; received after revision 14 March 2006; accepted 29 March 2006  相似文献   

12.
The determination of several of aldose reductase-inhibitor complexes at subatomic resolution has revealed new structural details, including the specific interatomic contacts involved in inhibitor binding. In this article, we review the structures of the complexes of ALR2 with IDD 594 (resolution: 0.66 Å, IC50 (concentration of the inhibitor that produced half-maximal effect): 30 nM, space group: P21), IDD 393 (resolution: 0.90 Å, IC50: 6 nM, space group: P1), fidarestat (resolution: 0.92 Å, IC50: 9 nM, space group: P21) and minalrestat (resolution: 1.10 Å, IC50: 73 nM, space group: P1). The structures are compared and found to be highly reproductible within the same space group (root mean square (RMS) deviations: 0.15 0.3 Å). The mode of binding of the carboxylate inhibitors IDD 594 and IDD 393 is analysed. The binding of the carboxylate head can be accurately determined by the subatomic resolution structures, since both the protonation states and the positions of the atoms are very precisely known. The differences appear in the binding in the specificity pocket. The high-resolution structures explain the differences in IC50, which are confirmed both experimentally by mass spectrometry measures of VC50 and theoretically by free energy perturbation calculations. The binding of the cyclic imide inhibitors fidarestat and minalrestat is also described, focusing on the observation of a Cl- ion which binds simultaneously with fidarestat. The presence of this anion, binding also to the active site residue His110, leads to a mechanism in which the inhibitor can bind in a neutral state and then become charged inside the active site pocket. This mechanism can explain the excellent in vivo properties of cyclic imide inhibitors. In summary, the complete and detailed information supplied by the subatomic resolution structures can explain the differences in binding energy of the different inhibitors.  相似文献   

13.
Glycosylation constitutes one of the most important posttranslational modifications employed by biological systems to modulate protein biophysical properties. Due to the direct biochemical and biomedical implications of achieving control over protein stability and function by chemical means, there has been great interest in recent years towards the development of chemical strategies for protein glycosylation. Since current knowledge about glycoprotein biophysics has been mainly derived from the study of naturally glycosylated proteins, chemical glycosylation provides novel insights into its mechanistic understanding by affording control over glycosylation parameters. This review presents a survey of the effects that natural and chemical glycosylation have on the fundamental biophysical properties of proteins (structure, dynamics, stability, and function). This is complemented by a mechanistic discussion of how glycans achieve such effects and discussion of the implications of employing chemical glycosylation as a tool to exert control over protein biophysical properties within biochemical and biomedical applications. Received 15 December 2006; received after revision 28 March 2007; accepted 25 April 2007  相似文献   

14.
I bring out the limitations of four important views of what the target of useful climate model assessment is. Three of these views are drawn from philosophy. They include the views of Elisabeth Lloyd and Wendy Parker, and an application of Bayesian confirmation theory. The fourth view I criticise is based on the actual practice of climate model assessment. In bringing out the limitations of these four views, I argue that an approach to climate model assessment that neither demands too much of such assessment nor threatens to be unreliable will, in typical cases, have to aim at something other than the confirmation of claims about how the climate system actually is. This means, I suggest, that the Intergovernmental Panel on Climate Change’s (IPCC׳s) focus on establishing confidence in climate model explanations and predictions is misguided. So too, it means that standard epistemologies of science with pretensions to generality, e.g., Bayesian epistemologies, fail to illuminate the assessment of climate models. I go on to outline a view that neither demands too much nor threatens to be unreliable, a view according to which useful climate model assessment typically aims to show that certain climatic scenarios are real possibilities and, when the scenarios are determined to be real possibilities, partially to determine how remote they are.  相似文献   

15.
Nineteenth-century spiritism was a blend of religious elements, the philosophy of mind, science and popular science and contacts with extraterrestrials were a commonplace phenomenon during spiritistic séances. Using the example of Carl du Prel (1839–1899) I show how his comprehensive mystic philosophy originated in a theory of extraterrestrial life. Carl du Prel used a Darwinian and monistic framework, theories of the unconscious and a Neo-Kantian epistemology to formulate a philosophy of astronomy and extraterrestrial life. He claimed that the mechanism of Darwinian selection is responsible for the distribution of stars and the orbits of the planets. In his speculations on the nature of extraterrestrial life he used the concept of organ projection to argue that technical solutions on earth will be realized organically on other planets and claimed that superior extraterrestrials have quantitatively and qualitatively different senses and thus different forms of intuition. A comparison with Camille Flammarion, spiritist and populariser of astronomy, demonstrates the contextual complexities of spiritism. In contrast to du Prel’s sober Neo-Kantian philosophical speculations, Flammarion was a late proponent of a French esoteric tradition that was rooted in romantic socialism, painted grand cosmological vistas and emphasized reincarnation. I put forward the hypothesis that current discourses on extraterrestrial life are affected by the spiritist tradition mainly through the ‘Golden Age’ science fiction literature of the 1940s and 50s and its successors. However, neither Carl du Prel nor Camille Flammarion contributed significantly to this tradition, which is mainly shaped by the psychical research of J. B. Rhine.  相似文献   

16.
Summary Larvae of danaine and ithomiine butterflies assimilate pyrrolizidine alkaloids painted on their larval host plants. This finding supports the theory of the common ancestral use of these compounds by Ithomiinae and Danainae.  相似文献   

17.
Plants pollinated and dispersed by different groups of birds offer different kinds of sugars in nectar and fruit pulp. The preferences and physiological traits of avian pollinators and seed dispersers are broadly correlated with the sugar composition of the nectar and fruit that they feed on and appear to have influenced the evolution of the sugar composition of the rewards that plants offer. Hummingbirds prefer sucrose whereas many nectar- and fruit-eating passerines prefer glucose and fructose. Preference for hexoses in passerines seems to be associated with poor sucrose assimilation resulting from two physiological mechanisms: lack of intestinal sucrase activity and fast passage rates. Sucrase activity absence appears to be restricted to a single phylogenetic group (the sturnid-muscicapid lineage). Fast passage rates seem to be characteristic of many small frugivores and to hinder the assimilation of complex nutrients that require hydrolysis before absorption. Hummingbirds have extremely specialized digestive traits that allow them to assimilate sucrose at high rates and with extremely high efficiency. These specialized digestive traits appear not to be present in many nectar-feeding passerines.  相似文献   

18.
Recent findings concerning human slow wave sleep (hSWS-stages 3+4; delta EEG activity) are critically reviewed. Areas covered include the significance of the first hSWS cycle; hSWS in extended sleep; relationship between hSWS, prior wakefulness and sleep loss; hSWS influence on sleep length; problems with hSWS deprivation; influence of the circadian rhythm; individual differences in hSWS, especially, age, gender and constitutional variables such as physical fitness and body composition. Transient increases in hSWS can be produced by increasing both the quality and quantity of prior wakefulness, with an underlying mechanism perhaps relating to the waking level of brain metabolism. Whilst there may also be thermoregulatory influences on hSWS, hypotheses that energy conservation and brain cooling are major roles for hSWS are debatable. hSWS seems to offer some form of cerebral recovery, with the prefrontal cortex being particularly implicated. The hSWS characteristics of certain forms of major psychiatric disorders may well endorse this prefrontal link.  相似文献   

19.
The balance between immunity and tolerance: The role of Langerhans cells   总被引:1,自引:1,他引:0  
Langerhans cells are immature skin-homing dendritic cells that furnish the epidermis with an immune surveillance system, and translate information between the internal and external milieu. Dendritic cells, in particular Langerhans cells, are gaining prominence as one of the potential principal players orchestrating the decision between immunity and tolerance. Langerhans cells capture aberrant self-antigen and pathogen-derived antigen for display to the efferent immune response. Recent evidence suggests redundancy in the antigen-presenting function of Langerhans cells, with dermal dendritic subsets capable of fulfilling an analogous role. There is mounting evidence that Langerhans cells can cross-prime T cells to recognize antigens. Langerhans cells are proposed to stimulate T regulatory cells, and are implicated in the pathogenesis of cutaneous T cell lymphoma.The phenotype of Langerhans cells, which may be tolerogenic or immunogenic, appears to depend on their state of maturity, inciting immunogen and cytokine environment, offering the potential for manipulation in immunotherapy. Received 6 August 2008; received after revision 18 September 2008; accepted 13 October 2008  相似文献   

20.
Eosinophil leukocytes have been studied for over 100 years, with various theories being advanced of the mechanism of their recruitment and function, especially in relation to the lesions of allergy, asthma and parasitism. Early notions of recruitment and function depended on observations of the cells in inflammatory lesions, while later theories have used additional information from in vitro studies. Many issues are still unresolved. This review aims to cover the older and more recent literature of the mechanisms of accumulation of eosinophil leukocytes and their functions, with a view to illuminating the controversies and difficulties of research in the area.  相似文献   

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