A participatory rural appraisal inthree West African countries examined thepossibility for replacing chemical pesticidesto control locusts and grasshoppers with abiological control method based on anindigenous fungal pathogen. The fungus iscurrently being tested at different sites inthe Sahel and in the humid tropics of WestAfrica. Structured group interviews, individualdiscussions, and field visits, were used toobtain farmers' perceptions of locust andgrasshoppers as crop pests, their quantitativeestimation of crop losses, and theirwillingness to pay for locust control. Farmersas well as plant protection officers generallyperceived (...) locusts and grasshoppers as importantpests that cause significant damage. Farmerswere aware of some of the risks of the use ofchemical pesticides, but not of the potentialalternatives. The use of the fungus in anoil-formulation and standard Ultra Low Volume(ULV) equipment was demonstrated, and theresults discussed with farmers. Theirimpressions of biological control werefavorable, and they expressed an interest inusing the technology. Farmers' expressedwillingness to pay for locust control is small,but not negligible. Locusts and grasshoppersare very visible pests and thus amenable topressure from farmers to local administrators,as well as by farmers' relatives in the city onthe national government. Therefore, politicalpressure for locust control is strong, althoughnational governments spend little on it,depending mostly on foreign donors. Donors areincreasingly worried about the environmentaleffect of the large amounts of chemicalpesticides used on locust control, and arepushing for more benign alternatives. Theresults of the present survey indicate thatthere may be a potential market for abiopesticide against grasshoppers and locustson cash crops in the humid areas. The potentialmarket in the Sahel depends on a reduction ofcosts or a subsidy of its price. This subsidycould be justified by the expected reduction inenvironmental and health costs when replacingchemical pesticides. Since donors are thecurrent purchasers of chemical pesticides forthe Sahel, they would also be expected to beinvolved in the purchase of the biologicalproduct. (shrink)
We introduce non-associative linear logic, which may be seen as the classical version of the non-associative Lambek calculus. We define its sequent calculus, its theory of proof-nets, for which we give a correctness criterion and a sequentialization theorem, and we show proof search in it is polynomial.
We show how to encode context-free string grammars, linear context-free tree grammars, and linear context-free rewriting systems as Abstract Categorial Grammars. These three encodings share the same constructs, the only difference being the interpretation of the composition of the production rules. It is interpreted as a first-order operation in the case of context-free string grammars, as a second-order operation in the case of linear context-free tree grammars, and as a third-order operation in the case of linear context-free rewriting systems. This (...) suggest the possibility of defining an Abstract Categorial Hierarchy. (shrink)
Recent studies have shown that Hugo de Vries did not rediscover Mendel's laws independently and that the classical story of the rediscovery of Mendel is largely a myth. Until now, however, no satisfactory account has been provided of the background and development of de Vries' views on heredity and evolution. The basic tenets of de Vries' Mutationstheorie and his conception of Mendelism are still insufficiently understood. It has been suggested that de Vries failed to assimilate Mendelism and that he (...) wrote his Mutationstheorie in a state of confusion. In this paper I argue that we can arrive at a better understanding by adopting a more symmetrical approach. My analysis will concentrate on three important aspects of de Vries' thinking which have been insufficiently appreciated until now. The first is that de Vries' reading of Mendel compelled him to change his conception of the hereditary particles, the pangenes, in a fundamental way. The second is de Vries' use of the notion of ‘hereditary force’. The third revolves around de Vries' typological species concept, which has been the source of much confusion in the literature. I shall conclude that de Vries did succeed in incorporating ‘Mendelism’ into his wider views on heredity and evolution, and that he did manage to handle his evidence in a consistent way. Yet I shall also conclude that Mendelism, in de Vries' interpretation, had nothing to do with ‘normal’ heredity and was mainly a laboratory phenomenon. (shrink)
It is argued that Hugo de Vries's conversion to Mendelism did not agree with his previous theoretical framework. De Vries regarded the number of offspring expressing a certain character as a hereditary quality, intrinsic to the state of the pangene involved. His was a shortlived conversion since after the ‘rediscovery’ he failed to unify his older views with Mendelism. De Vries was never very much of a Mendelian. The usual stories of the Dutch ‘rediscovery’ need, therefore, a considerable reshaping.
Hugo de Vries claimed that he had discovered Mendel's laws before he found Mendel's paper. De Vries's first ratios, published in 1897, for the second generation of hybrids were 2/3:1/3 and 80%:20%. By 1900, both of these ratios had become 3:1. These changing ratios suggest that as late as 1897 de Vries had not discovered the laws, although he asserted, from 1900 on, that he had found the laws in 1896. An Appendix details de Vries's Mendelian experiments as described (...) in the original edition of volume two of Die Mutationstheorie, but omitted entirely from the English translation. (shrink)
Joannes Geometres gehörte als einer der führenden Rhetoriker und Dichter seiner Zeit und als Offizier in der byzantinischen Armee – ϰαί σοφίη θάλλων ϰαί τόλμη ϰϱαδίης – zur politischen und literarischen Elite Konstantinopels. Nicht lange vor dem Jahr 986 wurde er aus dem Militärdienst entlassen; wie er selbst zu verstehen gibt, lag seine Tätigkeit als Soldat und Dichter, die bei seinen Zeitgenossen Neid ausgelöst hätte, diesem Ereignis zugrunde; die wirkliche Ursache war aller Wahrscheinlichkeit nach jedoch seine Sympathie für Basileios Nothos, (...) der seit 976 de facto als Kaiser des Reiches aufgetreten war, 985 aber gestürzt wurde. Wie dem auch sei, Joannes verließ seine luxuriöse Wohnung im Mesomphalos-Bezirk der Metropole und zog sich als Mönch ins Kloster Τα Κύϱου zurück; möglicherweise bekam er infolgedessen seinen zweiten Namen: Kyriotes. (shrink)
Im Jahre 1886 erregte I. Hilberg großes Aufsehen, als er in einem Artikel über die Autorschaft des Christus patiens auf die verschiedene Behandlung der dichrona bei den Jambographen der byzantinischen Epoche hinwies – die bis heute herrschende Anschauung geht dahin, dass α, ι und υ bei den byzantinischen Jambographen ausnahmslos mittelzeitig sind – und, je nach der absoluten Korrektheit in der Versifikation, sowohl was die Quantität als was die Zäsuren betraf, die Autoren in drei Gruppen meinte einreihen zu können: die (...) Classiker, die Epigonen und die Stümper. P. Maas griff diesen Standpunkt quasi unmittelbar an; er bemerkte sarkastisch, dass in diesem Fall Georgios Pisides, umstrahlt von der Glorie reinster Quantität einsam über allen anderen Dichtern in der einsamen Höhe seines „klassischen“ Himmels thronen würde, und dass die Byzantiner in Wirklichkeit von der Quantität der Vokale nichts hörten, da dieselben einfach isochron geworden waren. Dies hat nicht verhindert, dass F. Scheidweiler lange danach doch untersucht hat, ob die Poesie des Joannes Geometres noch der antiken Quantitätslehre entspricht, oder konkreter: dem Metrum des jambischen Trimeters:In diesem Beitrag möchte ich, mit den Untersuchungen von Scheidweiler als Richtschnur, der Frage nachgehen, in welchem Maβe der Dichter in seiner Μετάφϱασις των ώδων tatsächlich noch die antike Metrik respektiert. (shrink)
This word index to the Metaphrasis of the Odes by Joannes Geometres is based on the critical edition, which was published in GRBS 44 , 375-410. All words are listed in alphabetical order according to the following principles: nouns: singular and plural; adjectives: singular and plural; verbs: active , m iddle and passive. Remarks concerning gender, case, mood etc. are added if necessary.
In 1889 Hugo de Vries published " Intracellular Pangenesis " in which he formulated his ideas on heredity. The high expectations of the impression these ideas would make did not come true and publication was negated or reviewed critically. From the reactions of his Dutch colleagues and the discussion with the famous German zoologist August Weismann we conclude that the assertion that each cell contains all hereditary material was controversial and even more the claim that characters are inherited independently (...) of each other. De Vries felt that he had to convince his colleagues of the validity of his theory by providing experimental evidence. He established an important research program which resulted in the rediscovery of Mendel's laws and the publication of "The Mutation Theory." This article also illustrates some phenomena that go beyond an interesting episode in the development of theories of heredity. It shows that criticism from colleagues can move a researcher so deeply that he feels compelled to set up an extensive research program. Moreover it illustrates that it is not unusual that a creative scientist is only partially willing to take criticism on his theories into account. Last but not least it demonstrates that common opinion on the validity of specific arguments may change in the course of time. (shrink)
Building on Ben-Avi and Winter’s (2007) work, this paper provides a general “intensionalization” procedure that turns an extensional semantics for a language into an intensionalized one that is capable of accommodating “truly intensional” lexical items without changing the compositional semantic rules. We prove some formal properties of this procedure and clarify its relation to the procedure implicit in Montague’s (1973) PTQ.
De Vries' mutation theory has not stood the test of time. The supposed mutations of Oenothera were in reality complex recombination phenomena, ultimately explicable in Mendelian terms, while instances of large-scale mutations were found wanting in other species. By 1915 the mutation theory had begun to lose its grip on the biological community; by de Vries' death in 1935 it was almost completely abandoned. Yet, as we have seen, during the first decade of the present century it achieved an enormous (...) popularity. As this paper has tried to suggest, one of the principal reasons for this was that de Vries' theory served as a banner around which a whole crowd of disaffected Darwinians or anti-Darwinians could rally. However, not all of those who favored de Vries did so for quite the same reasons. Underlying the multitude of views ran several common threads: a dissatisfaction with current Darwinian theory born out of misunderstanding natural selection, a general misunderstanding of the nature of species, and a prejudice against speculative, nontestable theories in biology.Supporters of de Vries were not the only opponents of Darwinism, nor was the mutation theory the only alternative to natural selection. In the early twentieth century a number of theories had been proposed to explain away the problems which Darwin had left unsolved. There was the idea of orthogenesis, championed by the American paleontologists Cope, Osborn and others; organic selection (or orthoplasy) was championed by M. M. Baldwin and C. Lloyd Morgan; there were the concepts of convergent evolution proposed by Hermann Friedmann, the theory of physiological selection by John George Romanes, and the concepts of reproductive divergence by H. M. Vernon. Virtually none of these men either accepted or were strong supporters of the de Vriesian theory, for each had his own particular ‘ism” to advocate as the major factor in evolution. The existence of a large number of such theories, each purporting to be the explanation, was characteristic of evolutionary theory at the turn of the century. It is to a large extent the emphasis on such fragmentary concepts that retarded development of the comprehensive theory of evolution which emerged in the 1920's and 1930's. For the historian, however, a study of these alternative theories is instructive in trying to understand the inherent difficulties which Dawwinian theory posed to biologists at the time. De Vries' mutation theory serves historically as a mirror to reflect the critical mood of a generation hostile to the theory of natural selection.It has often been claimed that it was impossible to understand the mechanism of natural selection until it could be placed in genetic and mathematical terms. It is certainly true that great strides have been made in population genetics and the treatment of evolutionary concepts with mathematical tools in the last forty years. But the very people who developed the genetical and mathematical approach to evolution were already convinced of the essential correctness of Darwinian theory before they started. Advances in an understanding of Mendelian heredity aided greatly in solving one important issue for evolutionists: the origin of variations. And the rigor with which selection acted could best be studied by observing changes in gene frequencies (calculated mathematically) over a number of generations. But as this paper has shown, two of the basic problems which biologists faced in evaluating Darwinian theory at the turn of the century-the nature of species, and the criteria of what constituted an acceptable explanation in biological science-could not be answered directly by mathematics. What mathematical and genetical theory did do was to help convince the skeptics of the validity of the Darwinian proposition.The change in explanatory criteria which many hailed as de Vries' most important contribution to evolutionary theory seems to have been part of a general emergence of twentieth-century biology from the domination of theorizers in the nineteenth. It also marked the emergence of America from the domination of biological, and particularly evolutionary, influence of Europeans. The change occurred in three areas: in the kinds of questions asked: testable versus non-testable; in the kind of data sought: quantitative versus qualitative; and in the kinds of theories proposed: analytical and reductive—the attempt to see complex processes in terms of simpler components-as opposed to synthetic and speculative. Although ultimately wrong in his idea, de Vries and his theories rode high on the wave of “experimentalism” which was the harbinger of a new era in evolutionary theory. (shrink)
This note discusses lecture plates at the Hugo de Vries Laboratorium that may be relevant to Hugo de Vries's claim to have independently discovered Mendel's law of segregation. Dating when the plates were made is problematic.
A great deal is known about the technical issues surrounding the introduction of Hugo De Vries's mutation theory and the subsequent development of the modern genetical theory of natural selection. But so far little has been done to relate these events to the wider issues of the time. This article suggests that extra-scientific factors played a significant role, and substantiates this by comparing De Vries's respect for the original Darwinian spirit with Thomas Hunt Morgan's use of the mutation theory (...) as part of an attack on the whole philosophy of Darwinism. In particular, it is argued that Morgan's attitude was dictated by his moral objections to the picture of a world dominated by struggle. (shrink)
The almost simultaneous and overlapping discoveries of Mendel's forgotten work by Hugo de Vries, Carl Correns, and Erik von Tschermak gave rise to an intense rivalry, some jealousy, and more than a little illfeeling. De Vries, the first to announce the discovery, has been subjected to the charge that he wished to conceal his discovery and to obtain for himself the credit for having discovered what we now call Mendelism. This charge involves the statement that de Vries gave credit (...) to Mendel only after he had found that others had also read Mendel's papers. The evidence on which this charge is based is sketchy, and we can now show that at least that portion of it that is based on supposed alteration in the proof of de Vries' paper in the Berichte is without foundation. Unfortunately, de Vries gave three different accounts of how he was led to Mendel's work. Two of these involve Liberty Hyde Bailey.Bailey had listed Mendel's papers in a bibliography that he published in 1892 in The Rural Library. Bailey did not include this bibliography in the first edition (1895) of Plant Breeding or in its reprinting in 1896 and 1897. He did include the bibliography in the second edition (1902), but this was after de Vries and others had called attention to Mendel. In 1899, both Bailey and de Vries gave papers at the Hybrid Conference held at Chiswick, England, but we have no record of their having discussed Mendel. What evidence we have indicates that, at this time, neither of them had read Mendel's papers.De Vries wrote to Bailey that it was Bailey's listing of Mendel in the bibliography published in The Rural Library that led to his discovery of Mendel. Later, de Vries wrote to H. F. Roberts that he had first found a reference to Mendel in Bailey's Plant Breeding of 1895, where the bibliographic reference to Mendel's papers was not published. Finally, de Vries told Th. J. Stomps, who succeeded him at the University of Amsterdam, that he had first learned of Mendel early in 1900 from a reprint of Mendel's paper sent him by his friend Professor M. W. Beyerinck. Our present evidence favors Stomp's account as it shows that de Vries had not read Mendel's papers in 1899 but had early in 1900.Attempts to pinpoint de Vries' discovery of Mendel are aided in part, and in part confused, by the fact that he published five relevant papers in 1900. These papers were in press simultaneously, and some of them were altered in proof. Further confusion is due to the fact that at least three of them were published in the reverse order of their acceptance for publication. Unfortunately we do not have the crucial dates for all of the papers.J. Roy. Hort. Soc. 24: 69–75. A definitely pre-Mendelian paper given on 11 July 1899, and published in 1900 (possibly in April). The evidence for an alteration in proof after de Vries had read Mendel is shown by the fact that de Vries described a ratio of 99 to 54 as a 3 to 1 ratio.Rev. gén. botan. 12: 129–137. A Mendelian paper, giving the 3 to 1 ratio in the F2 generation of a cross between starchy and sugary corn. The paper is not dated by de Vries but it was published in the volume, 128 pages ahead of a paper de Vries dated 19 March. In a footnote, de Vries cites a paper by Correns that was published on 25 January, so we can tell that it was written or corrected in proof after this date. Here Correns showed de Vries that he had already read Mendel's paper. Any attempt by de Vries to ignore Mendel or get credit for Mendelism after 25 January would have been senseless. This date was nearly two months before de Vries' Berichte paper was submitted for publication.Ber. deut. botan. Ges. 18: 83–90. Accepted for publication 14 march, published 25 April. This paper gives Mendel full credit and stimulated the publications of Correns and von Tschermak. As de Vries was aware that Correns already knew of Mendel when the paper was first submitted, there was no occasion to alter it in proof.Rev. gén. botan. 12: 257–271. Dated by de Vries 19 March, but the proof was read after June. De Vries cites von Tschermak's paper in the Berichte that was published in June. The Revue paper is a Mendelian paper, and Mendel is cited on the last page.C. R. Acad. Sci. (Paris) 130: 845–847. Accepted for publication 26 March 1900. Reprint received by Correns 21 April. Mendel is not mentioned but de Vries' use of terms told Correns that de Vries had read Mendel's paper. First of the papers to be published, it caused Correns to assume that de Vries wanted the credit that was due Mendel.The three discoverers of Mendel did not form a mutual admiration society. (shrink)
One of the lecture plates in the collection of the Museum of the University of Amsterdam, generally believed to be used by the Dutch botanist Hugo de Vries, has aroused much discussion in relation to the question of whether or not de Vries knew Mendel's laws before he published his rediscovery of them in 1900. The plate suggests that de Vries observed Mendelian segregation ratios in 1895 and 1896 in the progeny of a cross of two varieties of Papaver (...) with different flower colour. According to his own account, it was through this cross that he first deduced the laws of Mendel in 1896. Some researchers have accepted the lecture plate as proof for this claim. My conclusion is that the plate was not made before 1900 but in 1904 for a lecture course in the USA and, as a consequence, that it is not a contemporary piece of evidence. A closer look at the descriptions of the depicted experiment in de Vries' publications revealed that its original goal was not to investigate segregation but to transfer a monstrosity. The segregation of the flower colour was a accidental event. No research notes of the experiment have survived, but a note on an experiment with Veronica, performed in the same successive years as the Papaver experiment and definitely intended to investigate the segregation of flower colour, shows that this experiment was interpreted in a theoretically conceived, more or less Mendelian way. Because of a sloppy performance, no firm conclusions could be drawn from the experiment, but de Vries clearly had the idea of Mendelian segregation in 1896. That he never brought it up before 1900 suggests that he could not establish the general validity of segregation rules, as is shown in the case of Veronica. The reading of Mendel's paper in 1900 immediately put an end to de Vries' doubts. He scrapped the failures and kept the successes, proudly presenting these to the public as proof for the laws of segregation and, at the same time, of the independence of his discovery. (shrink)
En Hugo de San Víctor, el amor es la raíz y el motivo fundamental del autoconocimiento. Con el conocimiento de sí no sólo procura el alma conocer lo que es, sino también y principalmente amar más. La confluencia del conocimiento y el amor expresan la estructura de la interioridad. Esta urdimbre interior es la que permite que las almas se eleven a las alturas de la mística. Sin autoconocimiento no sería posible recibir los dones del Espíritu Santo ni la (...) contemplación mística. (shrink)
The article offers an edition, translation and commentary of eight so-called book epigrams. They all stem from eleventh-century manuscripts containing the New Testament or commentaries on it, more specifically the Paris. Coisl. 199, the Vindobon. Theol. Gr. 302, the Paris. Coisl. 26, and the Vatic. Gr. 363. While most of them are unedited, the second one is a conflation of known epigrams, and the third an unknown version of a previously edited epigram.Although book epigrams are frequently encountered in Byzantine manuscripts, (...) the genre has not received much attention. In the track of the recently increasing interest in manuscripts as cultural artifacts in their own right, our commentary focuses on the relationship between epigram and manuscript, and the process of copying. It also discusses textual problems, structure, content, function, vocabulary, and metrical features of the poems.The analysis is enriched by parallels from other, mostly contemporary, book epigrams, which were collected during an ongoing database project at Ghent University. The comparison shows, among other things, that the material belonging to this genre is ‘recyclable’: it is constantly re-used, sometimes with slight but meaningful modifications. (shrink)
O presente artigo objetiva, ao revisitar a obra Oratio de hominis dignitate composta pelo humanista renascentista Giovanni Pico Della Mirandola, um duplo intento: sustentar que as noções de dignidade e liberdade, presentes nessa obra, se distanciam do pensamento cristão tradicional, de modo crítico, justamente porque derivam de uma leitura filosófica da teologia cristã da criação; e mostrar que a conclusão a respeito da noção de liberdade apresentada por Sartre no pensamento contemporâneo pode ser encontrada de modo germinal, guardada as devidas (...) proporções, na leitura piquiana da criação. Para tanto, exporemos uma breve retomada do contexto histórico-filosófico que permitiu ao filósofo engendrar a Oratio bem como suas pretensões para com essa obra; falaremos, em um segundo momento, como o platonismo religioso de Marsílio Ficino, principal matriz teórica a partir do qual os conceitos de dignidade e de liberdade foram modulados, foi recebido e desenvolvido no pensamento de Pico; e como as influências e as rupturas com pensamento de Ficino e a leitura filosófica da teologia cristã da criação são importantes para recolocar os conceitos de dignidade e de liberdade, permitindo assim entrever, por meio deles, semelhanças com o pensamento satreano. (shrink)
One of the riddles of the history of late medieval philosophy is the identity of a certain Hugo who is frequently quoted in manuscripts as well as in early prints. This article offers solutions to the relevant problems, identifying the work to which these quotations refer. One of the manuscripts presents the author’s name as “Hugo de Reyss,” Reyss being identified with Rees in North-Rhine/Westphalia. A passage in that work links the author to the University of Paris. Among (...) the Hugos documented at the University of Paris at the relevant time, Hugo de Hervorst is the most promising candidate. Hugo of Hervorst and his family had close relations to Rees. In sum, a chain of arguments leads to the identification of Hugo de Reyss as Hugo de Hervorst, whose academic and ecclesiastical careers can thus be outlined. Documented for the first time in 1372, he died in 1399. (shrink)
O presente artigo é uma discussão sobre a noção heideggeriana de Überwindung. Seu objetivo é duplo: por um lado,  mostrar a perspectiva que tal termo deve ser compreendido; por outro,  aprofundar esta perspectiva à luz de comentários ao aforismo I do texto Überwindung der Metaphysik. Para tanto, duas questões são postas: em que perspectiva e que questões estão implícitas quando Heidegger propõe o projeto da Überwindung der Metaphysik?; e por que uma Überwindung contém em si tantos problemas? De (...) modo a discutir e comentar tais questões, o artigo percorre dois caminhos:  faz-se uma análise da própria indicação heideggeriana da perspectiva de compreensão da Überwindung der Metaphysik, qual seja, revisitar, a partir de um olhar determinado, a construção da noção de história do ser. Esta, por sua vez, tem sua gênese antes mesmo da própria Kehre. Mais especificadamente, na reinterpretação que o próprio Heidegger faz de seu texto Vom Wesen der Wahrheit. A partir desta reconsideração feita por Heidegger e inserida em seu próprio texto, é possível detectar quatro teses fulcrais que traçam essencialmente a metafísica e que justificam a sua superação. São elas: [a] o fato de o ser, originariamente, se velar e provocar, historialmente, o seu esquecimento; [b] a relação entre a verdade do ser e a história, que se desenvolve como história do ser; [c] a ideia de que pertence ao ser um caráter originário de retração de si mesmo e que essa retração é um destino que pertence à história do pensamento metafísico e se configura na própria essência da metafísica; [d] afirmar que a certeza da manifestação da essência coincide com o seu fim.  Adentra-se, mediante uma aproximação pari passu, no aforismo I do texto Überwindung der Metaphysik, com intuito de comentar a problematicidade do termo Überwindung quando usado para repensar a metafísica à luz da perspectiva da história do ser. (shrink)
Resumen: El siguiente artículo presenta la formulación del concepto identidad cultural regional, a partir de una selección del aspecto mental de la cultura, lo que dio como resultado una definición discursiva narrativa de identidad cultural regional. Para esto se presentan fundamentos metafísicos, lingüísticos e históricos, y una contextualización compuesta de definiciones de identidad cultural, identidad cultural latinoamericana e identidad cultural regional. Respecto de esta última, se presentan aplicaciones al estudio de la Identidad Cultural de la Región de los Ríos, debido (...) a las características de este territorio como nueva región. El concepto resultante describe el fenómeno como un sentido del ser regional presente en la semiosfera cultural, formando parte de la memoria y del imaginario colectivo, manifestado en el modo de la unidad temática de una narración histórica coherente y ordenada, progresivamente más compleja y heterogénea, que combina la progresión lineal de los subtemas y el tema constante de la identidad cultural regional. (shrink)