Plants are considered as archetypes of the ramification phenomenon but numerous elementary processes occur in the elaboration of the shaping of each species. This paper aims to identify the part ascribed to different mechanisms in the morphogenesis of a Thallophyte, the red alga Antihamnion plumula.Agonistic-antagonistic models (Bernard-Weil, 1988) can be applied to this alga whose thallus includes two different kinds of whorls, pleuridian and cladomian. In each whorl the agonistic and antagonistic effects are expressed by the full development (S) of (...) the two branches and by their symmetry rate (R) respectively. Variations in S and R show the existence of particular pleuridian whorls having an intermediary dissymmetry and a rhythmic arrangement similarly to that of the cladomian whorls. A unilateral change of the system (removal of a lateral cladome) induces a transitory destabilisation mainly manifested by the stimulating ascendant flow throughout the thallus. (shrink)

Tool use research has suffered from a lack of consistent theoretical frameworks. There is a plethora of tool use definitions and the most widespread ones are so inclusive that the behaviors that fall under them arguably do not have much in common. The situation is aggravated by the prevalence of anecdotes, which have played an undue role in the literature. In order to provide a more rigorous foundation for research and to advance our understanding of the interrelation between tool use (...) and cognition, we suggest the adoption of Fragaszy and Mangalam's (2018) tooling framework, which is characterized by the creation of a body-plus-object system that manages a mechanical interface between tool and surface. Tooling is limited to a narrower suite of behaviors than tool use, which might facilitate its neurocognitive investigation. Indeed, evidence in the literature indicates that tooling has distinct neurocognitive underpinnings not shared by other activities typically classified as tool use, at least in primates. In order to understand the extent of tooling incidences in previous research, we systematically surveyed the comprehensive tool use catalog by Shumaker et al. (2011). We identified 201 tool use submodes, of which only 81 could be classified as tooling, and the majority of the tool use examples across species were poorly supported by evidence. Furthermore, tooling appears to be phylogenetically less widespread than tool use, with the greatest variability found in the primate order. However, in order to confirm these findings and to understand the evolution and neurocognitive mechanisms of tooling, more systematic research will be required in the future, particularly with currently underrepresented taxa. (shrink)

Darwin's “mystery of mysteries,” the origin of species, is caused by the evolution of speciation phenotypes, i.e. phenotypic differences that depress gene flow between daughter species during speciation. Postmating, prezygotic (PMPZ) differentiation characterizes many closely related species causing conspecific sperm precedence (CSP), wherein a female preferentially utilizes conspecific over heterospecific sperm in fertilization. Until recently, the components of CSP have been difficult to observe and study in internally fertilizing organisms. Research into the mechanisms of CSP is now progressing rapidly with (...) the help of new innovative research tools. With the recent development of a sperm labeling system enabling distinct labels for different males, direct observations of competing male sperm within the female reproductive tract are possible, revealing multiple PMPZ phenotypes that combine to cause CSP. The discovery of mechanisms underlying CSP predicts an exciting future for studies of PMPZ speciation phenotypes and possible general principles underlying the origin of species. (shrink)

Philosophie et sciences: voila un theme difficile, central, de notre temps, ou il est necessairement question de son sens. C'est ce sens qu'interrogent, d'une facon a la fois historique et problematique, les essais du present volume. J. Merleau-Ponty questionne les rapports entre sciences et vulgarisation scientifique. J. Ladriere pose le probleme de La normativite de la pensee scientifique. J. Lambert met en evidence le probleme du Livre de la Nature chez Galilee et Kepler. P. Kerszberg confronte les structures internes de (...) la philosophie critique kantienne et de la theorie de la relativite sur la question cosmologique. M. Richir analyse L'illusion transcendantale dans la theorie cantorienne des ensembles. B. d'Espagnat et G. Hottois evoquent le problemes des rapports difficiles, aujourd'hui, entre science et philosophie. (shrink)

The development of the typical cladomothallus of the red algae Antithaminion plumula (Ellis) Le Jolis [= Pterothamnion plumula (Ellis) Nägcli], (Rhodophyceae, Ceramiales) is simulated with the help of a formal language called L-systems. Two types of uniseriate filaments are distinguished: axial filaments of cladomes with indefinite growth and branching and pleuridia with definite growth and branching. The rythmical acropetal formation of secondary axes with basitonic arrangement contrasts with the intercalary basitonic formation of pleuridia, resulting in an acrotonic arrangement within an (...) axial segment. Five types of cells and two types of cell divisions intervene in the system. In addition, for the graphical representations, some morphological particularities of A. plumula are taken into account: the curvature of axial filaments, the extension of growth zones, variable cell generation times, and segment length variability along an axis. The incidence of these variables on the generated thallus form is emphasized, pointing to the singularities of A. plumula. (shrink)

[506] Je ne m’arrêterai pas à vous entretenir, Messieurs, sur la liaison des connaissances, qui sont l’objet de chacune des quatre classes de cette Académie. Ces liaisons sont celles de toutes les sciences, et les mêmes que celles qui enchaînent les vérités, de façon qu’elles en font un tout étroitement uni en toutes ses parties. La classe de physique expérimentale, à laquelle j’ai cru devoir me vouer, me donnera lieu de vous offrir un point de vue plus particulier, en ce (...) que je vais ramener... (shrink)

[421] Pour indiquer le sujet de ce mémoire, je commencerai par rapporter ce qui m’en a fourni l’occasion. C’est la lecture de Longin et la comparaison de ce qu’il dit sur le sublime avec ce que d’autres auteurs en ont dit. Longin commence par faire souvenir son ami Terentianus du petit traité de Cecilius, qui roule sur la même matière, et du peu de satisfaction que leur a causée la lecture de cet ouvrage. Il taxe le style de Cecilius de (...) bassesse et de répondre assez mal à la dignité de son su... (shrink)

We use evidence from cognitive psychology and the history of science to examine the issue of the theory-ladenness of perceptual observation. This evidence shows that perception is theory-laden, but that it is only strongly theory-laden when the perceptual evidence is ambiguous or degraded, or when it requires a difficult perceptual judgment. We argue that debates about the theory-ladenness issue have focused too narrowly on the issue of perceptual experience, and that a full account of the scientific process requires an examination (...) of theory-ladenness in attention, perception, data interpretation, data production, memory, and scientific communication. We conclude that the evidence for theory-ladenness does not lead to a relativist account of scientific knowledge. (shrink)

A análise da correspondência entre Espinosa e L. van Velthuysen pode ser bastante útil para aperfeiçoar nossa compreensão do Tractatus theologico-politicus e da filosofia de Espinosa em geral. Em sua correspondência, Espinosa é freqüentemente evasivo e lento para ver (ou, ao menos, para reconhecer) um ponto. É uma questão interessante como deveríamos dar conta destas deficiências em suas respostas, e sua correspondência com Velthuysen seria uma boa oportunidade para provar a perspectiva de Bennett. O artigo está dividido em três partes: (...) 1) Velthuysen antes de Espinosa e o contexto de suas críticas; 2) um exame das Cartas 42 e 43; e 3) o debate em torno do deísmo e do ateísmo. (shrink)

Oxford Scholarly Classics is a new series that makes available again great academic works from the archives of Oxford University Press. Reissued in uniform series design, the reissues will enable libraries, scholars, and students to gain fresh access to some of the finest scholarship of the last century.

The paper is concerned with explaining some of the principal theoretical developments in elementary particle physics and discussing the associated methodological problems both in respect of heuristics and appraisal. Particular reference is made to relativistic quantum field theory, renormalization, Feynman diagram techniques, the analytic S-matrix and the Chew — Frautschi bootstrap.

Objective—To explore the opinions of unpaid healthy volunteers on the payment of research subjects.Design—Prospective cohort.Setting—Southern Alberta, Canada.Participants—Medically eligible persons responding to recruiting advertisements for a randomised vaccine trial were invited to take part in a study of informed consent at the point at which they formally consented or refused trial participation. Of 72 invited, 67 returned questionnaires at baseline and 54 at follow-up.Outcome measures—Proportions of persons who agreed or disagreed with three close-ended statements on the payment of research subjects; themes (...) and categories identified by content analysis of responses to an open-ended question.Results—A minority agreed with paying either patient or healthy volunteer participants. Opinions did not change over time. Participants' comments addressed: benefits and drawbacks to research participation; benefits and drawbacks to paying research participants; conditions under which payment of research subjects would be acceptable, and the nature of acceptable recognition. Acceptable conditions were to improve problematic recruitment, to reimburse costs, and to recognise participants, particularly for their time investment. Both non-monetary and monetary recognition of volunteers were thought to be appropriate.Conclusions—Most unpaid volunteers disagreed with paying research participants. The themes arising from their comments are similar to those that have been raised by ethicists and suggest that recognising the time and effort of participants should receive greater emphasis than presently occurs. (shrink)

Résumé : Le PPBS a été conçu comme un instrument destiné à ceux qui décident de l'allocation des ressources publiques : il doit leur permettre de prendre de meilleures décisions. S'il est très difficile de repérer et de juger les choix que le développement du système a inspirés aux Etats-Unis, il n'en est pas mains certain que ses résultats tangibles sant maigres car la masse des anciens programmes, principale source potentielle de moyens nouveaux, n'a guère été remise en question.La valeur (...) intrinsèque du PPBS ne peut être mise en cause. Ce qui doit l'être, c'est la lenteur de son développement, qui demeure peu avancé. Cette lenteur s'explique, car le système ne peut produire des fruits dans une terre stérile qu'on n'a pas préparée.La brutalité et les maladresses de l'opération déclenchée en 1965 dans le gouvernement fédéral américain ne pouvaient que renforcer la résistance au changement et retarder, sinon compromettre, le succès final. Les perspectives demeurent heureusement favorables, puisque la nouvelle administration ne semble pas décidée à faire machine arrière et que les Etats et Villes ont démarré sous de bien meilleurs auspices.La principale conclusion qu'imposent les expériences américaines est que toute juridiction intéressée par le PPBS doit impérativement développer, de la façon la plus générale, la volonté d'instaurer le système et s'assurer les moyens de le faire. C'est dire qu'il est peu sage d'engager la bataille sur tous les fronts à la fois : il faut tenter des percées. Mais c'est dire aussi combi en l'information et la formation sant essentielles. A cet égard, l'installation généralisée de certains éléments du système, à savoir la structure de programmes et le budget-programme, loin de présenter des inconvénients, peut constituer un excellent exercice en dehors de son utilité directe pour le preneur de décision. La bataille en cause est surtout celle de la conviction: l'outil est prêt, il est bon, encore faut-il que l' ouvrier accepte de s'en servir.Samenvatting:Planning-programming-budgeting werd ontworpen als een instrument voor diegenen die beslissen over de toewijzing van de overheidsmiddelen.Dit instrument moet de beslissers in staat stellen betere beslissingen te treffen. Het is niet makkelijk deze beslissingen op te sporen en te beoordelen welke in de Verenigde Staten getroffen werden onder invloed van de ontwikkeling van deze systeembenadering. Toch is het met vrij grote zekerheid te stellen dat de tastbare resultaten gering zijn omdat de veelheid aan oude programma's die tenslotte toch de voornaamste potentiële bronnen zijn van nieuwe middelen, nooit werden aangevochten.De intrinsieke waarde van PPBS kan daarom evenwel niet worden genegeerd. Wat wel dient aangeklaagd is de traagheid van zijn aanslepende ontwikkeling. Deze traagheid is te verklaren door het feit dat het systeem slechts vruchten kan afwerpen zo het ingeplant wordt in degelijk voorbereid terrein.De brutaliteit en de onhandigheden bij de operatie die in 1965 werd ingezet in het amerikaans federaal overheidsbestel konden niets anders dan de weerstand tegen de verandering versterken en afbreuk doen aan het uiteindelijk slagen van het systeem. Gelukkiglijk blijven de vooruitzichten gunstig want de nieuwe beleidsvoerders sinds de presidentsverkiezingen, blijken ermee te willen doorgaan en de staten en lokale overheden zijn ermee van wal gestoken onder veel betere omstandigheden. Het doorslaggevend besluit uit de amerikaanse ervaringen terzake is wel dat elke instantie welke belangstelling heeft voor PPBS, nodig moet op zo breed mogelijk vlak de wil doen groeien om het systeem te ontwikkelen en er ook de nodige middelen toe ter beschikking stellen. Dit betekent tevens dat het weinig aan te bevelen is de strijd op alle fronten terzelvertijd aan te binden maar wel geleidelijk doorbraken te verwezenlijken. Dit brengt dan evenwel ook met zich dat informatie en vorming essentieel zijn bij deze strategie. In dit verband moet dan ook gezegd worden dat reeds het invoeren van sommige deelementen van het systeem, zoals de programmastructuur en het programmabudget, voor de beslisser nuttig kan zijn voor zijn persoonlijk inzicht en vorming.De te voeren actie dient nog slechts te worden toegespitst op het overtuigen van de verantwoordelijken. Het instrument is immers gebruiksklaar en degelijk, er is alleen nog het wachten op de wil van de gebruiker dit instrument ter hand te nemen. (shrink)

A Papyrus commentary on Alcman published in 19571 brings us news of a poem in which Alcman “physiologized”. The lemmata and commentary together witness to a semi-philosophical cosmogony unlike any other hitherto known from Greece. The evidence is meagre, but it seems worth while to see what can be made of it; for it is perhaps possible to go a little farther than has so far been done.

Histories of literature tend to treat Stesichorus as just one of the lyric poets, like Alcman or Anacreon. But the vast scale of his compositions puts him in a category of his own. It has always been known that his Oresteia was divided into more than one book; P. Oxy, 2360 gave us fragments of a narrative about Telemachus of a nearly Homeric amplitude; and from P. Oxy. 2617 it was learned that the Geryoneis contained at least 1,300 verses, the (...) total being perhaps closer to two thousand. Even allowing for the shorter lines, this was as long as many an epic poem. Indeed, these were epic poems, in subject and style as well as in length: epics to be sung instead of recited. What was behind them ? Who was this Stesichorus, and how did he come to be, in Quintilian's phrase, ‘sustaining on the lyre the weight of epic song’ ? The biographical problem must be tackled first. The question of Stesichorus’ historical setting and date is confused by legendary elements as well as by contradiction in the sources. On the whole scholars remain spellbound by the specious precision of the Suda's dates , although it has long been realized that they are founded on nothing but the assumption that Stesichorus was younger than Alcman and older than Simonides. There have been excellent discussions by Wilamowitz and Maas, but they seem to have had little influence. (shrink)