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1.
This study proposes an explanation for the choice of topics Galileo addressed in Day 1 of his 1638 Two New Sciences, a section of the work which has long puzzled historians of science. I argue that Galileo’s agenda in Day 1, that is the topics he discusses and the questions he poses, was shaped by contemporary teaching commentaries on Books 3 through 8 of Aristotle’s Physics. Building on the insights and approach of theorists of reader reception, I confirm this interpretation by examining the response of professors of natural philosophy at the Jesuit Collegio Romano to Galileo’s text.  相似文献   

2.
Summary Males ofPodisus fretus (Hemiptera: Pentatomidae) release a long-range attractant pheromone containing linalool (49.0%), (E)-2-hexenal (34.5%), benzyl alcohol (12.0%), nerolidol (2.0%),-terpineol (1.1%), and traces of several other compounds. The eastern yellowjacket,Vespula maculifrons (Hymenoptera: Vespidae), is attracted to artificial pheromones forP. fretus and for the sympatric species,Podisus maculiventris.The authors thank Mr T.J. Henry of the USDA Systematic Entomology Laboratory and Dr J.E. McPherson, Southern Illinois University, for examining the pentatomid species and Dr A.S. Menke, USDA-SEL, for determining the yellowjacket species. We also thank S. Wilzer for technical assistance. Mention of a company name does not imply endorsement by the US Department of Agriculture.  相似文献   

3.
Diophantos' solutions to the problems of Arithmetica have been the object of extensive reading and interpretation in modern times, especially from the point of view of identifying ``hidden steps' or ``general methods'. In this paper, after examining the relevance of various interpretations given for the famous problem II 8 in the context of modern algebra or geometry, we focus on a close reading of the ancient text of some problems of Arithmetica in order to investigate Diophantos' solving practices. This inquiry reveals certain pointers, which enable us to create a framework for defining the generality of Diophantos' methods. An erratum to this article can be found at  相似文献   

4.
ABSTRACT

This paper explores the rules for the expurgation of texts of astrology in the Iberian Indices of forbidden books. It addresses the prohibitions put forward in Rule IX of the Index of Trent and the bull Coeli et terrae of Sixtus V, and studies its impact on the rules and their interpretation in the Spanish and Portuguese Indices, in particular, those published in the first decades of the seventeenth century: the Spanish Index librorum prohibitorum et expurgatorum of 1612 and the Portuguese Index auctorum damnatae memoriae of 1624. It shows how these indices offer a more meticulous examination of the prohibitions providing not only more detail regarding the different practices of astrology, but also explicitly accept the doctrine of inclinations of Thomas Aquinas as a central rule to deal with astrological judgments on human behaviour. It also highlights some specific details of the practice of censorship of astrological books by examining case studies of censored Portuguese and Spanish astrological publications. These provide new dimensions and highlight significant differences between the theoretical rules, practical guidelines, and actual restriction of astrological content.  相似文献   

5.
ABSTRACT

During the sixteenth and seventeenth centuries, the Inquisition was the institution most invested in the censorship of printed books in the Portuguese empire. Besides publishing the Indices of Forbidden Books, the Holy Office was also responsible for overseeing their implementation and ensuring their efficacy in preventing the importation, reading, and circulation of banned books. Overall, the sixteenth-century Indices condemned 785 authors and 1081 titles, including 52 authors and 85 titles of medicine, natural history, natural philosophy, astronomy, chronology, cosmography, astrology, and divinatory arts. By looking at the largest collection of early modern scientific books in Portugal, I will argue that a closer inspection of marginalia and ownership, and the establishment of a typology of expurgations is essential for the comprehension of the actual practices and the mechanisms of censorship. By examining the material evidence of censorship, in order to reconstruct expurgation practices, this paper reveals the processes and effectiveness of ecclesiastical control in the Portuguese Inquisition and highlights the differences between what inquisitors wrote in the Indices and what others put into practice.  相似文献   

6.
This paper examines the purport of epact tables encountered on scientific instruments, and explains their use. The epact is a valuable chronological aid for calculating the age of the moon. In handbooks of chronology, usually two types of epacts are distinguished: the epact used in medieval times, and the so-called Lilian epact used after 1582 in the Gregorian perpetual calendar. By examining the rules for calculating the age of the moon, it turns out that the Julian and Gregorian epacts encountered on instruments must be distinguished from the medieval and Lilian epacts. It is shown that the Julian epact was already in use in 1478, and that, by adjusting for the shift of ten days in the date of the vernal equinox, the Gregorian epact was derived from it in 1582. The common association of the latter with the Lilian epact employed in the Gregorian perpetual calendar is incorrect. It is further shown that in contrast to the medieval and Lilian epacts, which served purely ecclesiastical purposes, the Julian and Gregorian epacts were mainly used to calculate the true age and zodiacal position of the moon. This knowledge was applied to secular interests such as ‘lunar astrology’, tidal computations, and the conversion of lunar into solar time.  相似文献   

7.
8.
The ability to regulate energy balance at both the cellular and whole body level is an essential process of life. As western society has shifted to a higher caloric diet and more sedentary lifestyle, the incidence of type 2 diabetes (non-insulin-dependent diabetes mellitus) has increased to epidemic proportions. Thus, type 2 diabetes has been described as a disease of 'chronic overnutrition'. There are abundant data to support the relationship between nutrient availability and insulin action. However, there have been multiple hypotheses and debates as to the mechanism by which nutrient availability modulates insulin signaling and how excess nutrients lead to insulin resistance. One well-established pathway for nutrient sensing is the hexosamine biosynthetic pathway (HSP), which produces the acetylated aminosugar nucleotide uridine 5′-diphospho-N-acetylglucosamine (UDP-GlcNAc) as its end product. Since UDP-GlcNAc is the donor substrate for modification of nucleocytoplasmic proteins at serine and threonine residues with N-acetylglucosamine (O-GlcNAc), the possibility of this posttranslational modification serving as the nutrient sensor has been proposed. We have recently directly tested this model in adipocytes by examining the effect of elevated levels of O-GlcNAc on insulin-stimulated glucose uptake. In this review, we summarize the existing work that implicates the HSP and O-GlcNAc modification as nutrient sensors and regulators of insulin signaling. RID="*" ID="*"Corresponding author.  相似文献   

9.
Summary Resilin is present in the endocuticle of the flexible abdominal intersegmental cuticle of the, physogastric queen of the termite,Odontotermes obesus (Rambur). Resilin seems to assist in the extension of abdomen of the queen termites during physogastry.Acknowledgments. I am grateful to Dr S. O. Anderson for examining the cuticle in the fluorescent microscope. I thank Prof. R. G. Michael for interest in this work, Prof. P. S. Ramakrishnan for providing UV Lamp (Toshnival) for the examination of chromatograms and Mr Sudip Dey for valuable discussions.Previously called A. Sannasi.  相似文献   

10.
During the long eighteenth century, boundaries between theology and natural philosophy, between imaginary and factual travel narratives, between fiction and social commentary, were far more fluid than they are today. To explore these relationships, this paper links Mary Shelley’s Frankenstein—a book often hailed as the first science fiction novel—to two earlier works which are now less well known: Edmond Halley’s article about terrestrial magnetism, in which he suggested that God had created inhabited illuminated cavities inside the earth; and a satirical fantasy voyage written by the Danish author Ludvig Holberg, but published anonymously as Niels Klim’s journey to the underground and immediately translated into many languages. Attention is focussed on how the ambiguous presentation of these and other texts blurs any straightforward classification of genres. The aim of examining these writers together is not to search for direct mappings from one project to another, but instead to introduce Holberg’s unfamiliar yet important book and also to cast new light on Frankenstein, one of England’s most famous works of literature.  相似文献   

11.
Mary Orr 《Annals of science》2014,71(2):206-240
Since first appearance, reviews and accounts of The Fresh-Water Fishes of Great Britain (1828–1838) have been surprisingly few. All agree that this rare work is remarkable for its illustrations. Its importance as a whole in the history of ichthyology, however, is largely unknown, or ignored. This article therefore constitutes the first study of the textual and contextual significance of The Fresh-Water Fishes of Great Britain. By examining in chronological order where, and by whom, the work was first reviewed and referenced until the 1860s, the extraordinary contributions that its author, Sarah Bowdich, made to ichthyology at the forefront of the field in the late 1820s can better be appreciated. Indeed, this multiple evidence demonstrates Sarah Bowdich's merits as an ichthyologist of the first order, and as the first woman ichthyologist. But establishing the significance of The Fresh-Water Fishes of Great Britain for the history of ichthyology then raises a further question. Why has it and its author been so ignored or forgotten? By returning for answers to the fields of ichthyology already considered, the article proposes that Sarah Bowdich's different angles on fish offer lines of investigation that are still important for the field today.  相似文献   

12.
The European rabbit (Oryctolagus cuniculus) is now widely distributed throughout the world as a result of transportation by man. The original populations, however, were confined to southern France and Spain. In order to investigate the role of human intervention in determining the genetic diversity of rabbit populations, we are studying the origin of rabbits introduced onto a small Mediterranean island (Zembra) near Tunis over 1400 years ago, by examining ancient DNA extracted from rabbit bones found both on Zembra and on the European mainland. Ancient DNA was successfully extracted from rabbit bones found at two archaeological sites dated to at least the Early Bronze Age (more than 3500 years ago) in south-central France, and compared to that found in modern mainland and island populations using a small variable region of the cytochromeb gene. The results confirm that the Zembra Island population is descended from that present over 1400 years ago. The technical aspects of DNA extraction from bones and the implications of this type of research for determining the origin of introduced rabbit populations are discussed.  相似文献   

13.
By using the example of a single proposition and its diagrams, this paper makes explicit a number of the processes in effect in the textual transmission of works in the exact sciences of the ancient and medieval periods. By examining the diagrams of proposition 13 as they appear in the Greek, Arabic, and Latin traditions of Aristarchus's On the Sizes and Distances of the Sun and Moon, we can see a number of ways in which medieval, and early modern, scholars interpreted their sources in an effort to understand and transmit canonical ancient texts. This study highlights the need for modern scholars to take into consideration all aspects of the medieval transmission in our efforts to understand ancient practices.  相似文献   

14.
In examining stochastic models for commodity prices, central questions often revolve around time‐varying trend, stochastic convenience yield and volatility, and mean reversion. This paper seeks to assess and compare alternative approaches to modelling these effects, with focus on forecast performance. Three specifications are considered: (i) random‐walk models with GARCH and normal or Student‐t innovations; (ii) Poisson‐based jump‐diffusion models with GARCH and normal or Student‐t innovations; and (iii) mean‐reverting models that allow for uncertainty in equilibrium price. Our empirical application makes use of aluminium spot and futures price series at daily and weekly frequencies. Results show: (i) models with stochastic convenience yield outperform all other competing models, and for all forecast horizons; (ii) the use of futures prices does not always yield lower forecast error values compared to the use of spot prices; and (iii) within the class of (G)ARCH random‐walk models, no model uniformly dominates the other. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

15.
Alexis Fontaine des Bertins (1704–1771) was the first French mathematician to introduce what we would now regard as results in the calculus of several variables. One example is Fontaine's theorem nF = (?F/?x)x + (?F/?y)y of 1737 for homogeneous expressions F of degree n in x and y. Many years later Fontaine indicated this particular result to have been ‘a continuation of the method of solution’ introduced by him in 1734 to solve the problem of the tautochrones. It is tempting to disregard this announcement, since the method applied to the tautochrones was a method of variations and not manifestly an exercise in the calculus of several variables. Do we have just another case of a mathematician's confusion about the origins of his earlier work? In this paper I describe Fontaine's possible intentions in his remarks.  相似文献   

16.
Summary A set of fundamental issues in neuroethology concerns the neural mechanisms underlying behavior and behavioral plasticity. We have recently analyzed these issues by combining a simple systems approach in the marine molluscAplysia with a developmental analysis aimed at examining the emergence and maturation of different forms of behavior and learning. We have focussed on two kinds of questions: 1) How are specific neural circuits developmentally assembled to mediate different types of behaviors? and 2) how is plasticity integrated with these circuits to give rise to different forms of learning? From our analysis of the development of learning and memory inAplysia, several themes have emerged: 1) Different forms of learning emerge according to different developmental timetables. 2) Cellular analogs of learning have the same developmental timetables as their respective forms of behavioral learing. 3) An analysis of non-decremented responses prior to the emergence of sensitization reveals a novel inhibitory process on both behavioral and cellular levels. 4) Sensitization emerges simultaneously in diverse response systems, suggesting an underlying general process. 5) A widespread proliferation of central neurons occurs in the same developmental stage as the emergence of sensitization, raising the possibility that some aspect of the trigger for neuronal proliferation may also contribute to the expression of sensitization.  相似文献   

17.
Summary Important facts in connection with the occurrence of N-Nitroso compounds in tobacco smoke have been summarized. This paper reports on analytical methods for the identification of N-Nitroso compounds. The figures known about nitrate content and volatile bases of tobacco, as well as the nitrogen oxides and volatile bases of tobacco smoke as precursors of N-Nitroso compounds, are summarized. The third order reaction of secondary amines with an equimolar mixture of nitric oxide and nitrogen dioxide is a precondition for the formation of N-Nitroso compounds in tobacco smoke. While examining tobacco smoke for N-Nitroso compounds, temperature and time conditions have to be adapted to the natural smoking process. The use of solvent as well as cold traps has to be avoided to exclude the formation of artifacts. Analyses completed under these conditions furnished results of 0.004µg of a mixture consisting of N-Nitroso-dimethylamine and N-Nitroso-pyrrolidine, calculated as N-NO per cigarette. A number of animalexperimental preconditions are still lacking, to judge the biological effects of these extraordinarily small amounts of N-Nitroso compounds.  相似文献   

18.
We have previously demonstrated that Mytilus edulis pedal ganglia contain opiate alkaloids, i.e., morphine and morphine 6 glucuronide (M6G), as well as mu opiate receptor subtype fragments exhibiting high sequence similarity to those found in mammals. Now we demonstrate that M6G stimulates pedal ganglia constitutive nitric oxide (NO) synthase (cNOS)-derived NO release at identical concentrations and to similar peak levels as morphine. However, the classic opiate antagonist, naloxone, only blocked the ability of morphine to stimulate cNOS-derived NO release and not that of M6G. CTOP, a mu-specific antagonist, blocked the ability of M6G to induce cNOS-derived NO release as well as that of morphine, suggesting that a novel mu opiate receptor was present and selective toward M6G. In examining a receptor displacement analysis, both opiate alkaloids displaced [3H]-dihydromorphine binding to the mu opiate receptor subtype. However, morphine exhibited a twofold higher affinity, again suggesting that a novel mu opiate receptor may be present. Received 1 November 2001; received after revision 1 February 2002; accepted 1 February 2002  相似文献   

19.
On December 13, 1679Newton sent a letter toHooke on orbital motion for central forces, which contains a drawing showing an orbit for a constant value of the force. This letter is of great importance, because it reveals the state ofNewton's development of dynamics at that time. Since the first publication of this letter in 1929,Newton's method of constructing this orbit has remained a puzzle particularly because he apparently made a considerable error in the angle between successive apogees of this orbit. In fact, it is shown here thatNewton's implicitcomputation of this orbit is quite good, and that the error in the angle is due mainly toan error of drawing in joining two segments of the oribit, whichNewton related by areflection symmetry. In addition, in the letterNewton describes quite correctly the geometrical nature of orbits under the action of central forces (accelerations) which increase with decreasing distance from the center. An iterative computational method to evaluate orbits for central forces is described, which is based onNewton's mathematical development of the concept of curvature started in 1664. This method accounts very well for the orbit obtained byNewton for a constant central force, and it gives convergent results even for forces which diverge at the center, which are discussed correctly inNewton's letterwithout usingKepler's law of areas.Newton found the relation of this law to general central forces only after his correspondence withHooke. The curvature method leads to an equation of motion whichNewton could have solvedanalytically to find that motion on a conic section with a radial force directed towards a focus implies an inverse square force, and that motion on a logarithmic spiral implies an inverse cube force.  相似文献   

20.
Summary Polyhedral inclusion bodies (P.I.B.) of a nuclear polyhedrosis virus ofHeliothis punctigera (Lep.) were found in excreta ofNabis tasmanicus (Het.), a predator ofH. punctigera. An immunofluorescent counting method was used to estimate numbers of P.I.B. Bioassays demonstrated that no loss of infectivity occurred during passage through the gut.Acknowledgment. I am grateful for the comments and criticism offered by Dr D.E. Pinnock, I thank D.J. Cooper for preparation of materials for the immunofluorescent counting method and J. Hardy for supplying me with eggs ofH. punctigera; all of Department of Entomology, Waite Agricultural Research Institute, Glen Osmond, South Australia.  相似文献   

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