Determination of diel periodicity of sex pheromone release in three species of Lepidoptera by ‘closed-loop-stripping’

Summary By means of closed-loop-stripping and subsequent GC analyses the diel periodicity of release of (Z)-11-hexadecenyl acetate, (E)-8-dodecenyl acetate, and (Z)-9-tetradecenyl acetate, the main constituents of the respective sex pheromone blends ofMamestra brassicae, Cryptophlebia leucotreta andSpodoptera sunia females, was determined.Pheromones, 64. For the 63rd contribution we have taken from: Szöcs, G., Toth, M., Bestmann, H. J., Vostrowsky, O., Heath, R. R., and Tumlinson, J. H., Z. Naturforsch.42c (1987) 165; Pheromones, 62: Bestmann et al.¹³.     

‘Holding’ and ‘endorsing’ claims in the course of scientific activities

My principal aims are to show that holding, adopting and endorsing (definitions of which I provide) are distinct cognitive attitudes that may be taken towards claims at different moments of scientific activities, and that none of them are reducible to acceptance (as defined by Jonathan Cohen); to explore in detail the differences between holding and accepting, using the controversies about GMOs to provide illustrations; and to draw some implications pertinent to democratic decision-making concerning public policies about science and technology, and to the responsibilities that scientists thereby incur.     

Quine's ‘needlessly strong’ holism

Quine is routinely perceived as having changed his mind about the scope of the Duhem-Quine thesis, shifting from what has been called an 'extreme holism' to a more moderate view. Where the Quine of 'Two Dogmas of Empiricism' argues that “the unit of empirical significance is the whole of science” (1951, 42), the later Quine seems to back away from this “needlessly strong statement of holism” (1991, 393). In this paper, I show that the received view is incorrect. I distinguish three ways in which Quine's early holism can be said to be wide-scoped and show that he has never changed his mind about any one of these aspects of his early view. Instead, I argue that Quine's apparent change of mind can be explained away as a mere shift of emphasis.     

‘Identify’ and ‘lock in’: molecular integration during synaptic target recognition

Synaptic target recognition is a complex molecular event. In a differentiating presynaptic terminal, relatively ‘rare’ molecules first detect the cell identity of the synaptic target. Subsequently, many ‘common’ molecules continue the process of synaptogenesis. We present a theoretical framework for understanding synaptic target recognition and discuss the features of its molecular components and their integration, drawing on the rapid progress made in recent studies.     

‘Heated’ Debates in Apoptosis

Hippocrates’ assertion that ‘what the lance does not heal, fire will’ underscores the fact that for thousands of years heat has been used to treat a variety of diseases, including cancer. Indeed, spontaneous tumor remission has been observed in patients following feverish infection [1], and expression of activated oncogenes, such as Ras, can render tumor cells sensitive to heat compared with normal cells [2, 3]. In the past, a primary drawback to the use of heat as a clinical therapy was the inability to selectively focus heat to tumors in situ. Of late, however, several approaches have been devised to deliver heat more precisely, including the use of heated nanoparticles, making hyperthermia a more clinically tractable treatment option [4, 5]. Despite these practical advances, the mechanisms responsible for heat shock-induced cell death remain controversial and ill-defined. In this Visions and Reflections we discuss recent findings surrounding the initiation of heat shock-induced apoptosis, and propose future areas of research. Received 17 March 2007; received after revision 25 April 2007; accepted 22 May 2007     

‘Soup’ vs. ‘Sparks’: Alexander Forbes and the Synaptic Transmission Controversy

During the twentieth century, a controversy raged over the role of electrical forces and chemical substances in synaptic transmission. Although the story of the ‘main’ participants is well documented, the story of ‘lesser’ known participants is seldom told. For example, Alexander Forbes, who was a prominent member of the axonologists, played an active role in the controversy and yet is seldom mentioned in standard accounts of the controversy. During the 1930s, Forbes incorporated chemical substances into his theory of synaptic transmission, advocating a complementarity model for the role of electrical forces and chemical substances. By focusing on Forbes and the axonologists, the controversy is simply more than a debate over ‘soup’ vs. ‘sparks’ but also involves the relative roles of electrical forces and chemical substances in synaptic transmission. The implications of this case study for the nature of scientific controversies are also discussed.     

Isaac Newton’s ‘Of Quadrature by Ordinates’

In Of Quadrature by Ordinates (1695), Isaac Newton tried two methods for obtaining the Newton–Cotes formulae. The first method is extrapolation and the second one is the method of undetermined coefficients using the quadrature of monomials. The first method provides $n$ -ordinate Newton–Cotes formulae only for cases in which $n=3,4$ and 5. However this method provides another important formulae if the ratios of errors are corrected. It is proved that the second method is correct and provides the Newton–Cotes formulae. Present significance of each of the methods is given.     

‘Pitfalls’ in immune electron microscopy

Zusammenfassung Es werden die Fehlerquellen diskutiert, die bei der Untersuchung von Antigenen auftreten, wenn zu deren elektronenmikroskopischer Darstellung Antikörper, markiert mit Ferritin, verwendet werden. Durch geeignete Wahl der Fixierung können einige dieser Schwierigkeiten beseitigt werden.     

Crystalline acetates from ‘Croton Resin’

Zusammenfassung Durch Hydrolyse des aus Krotonöl gewonnenen Krotonharzes wurde eine empfindliche, wasserlösliche Polyhydroxyverbindung gewonnen, die teilweise als das bereits bekannte Alkohol-Phorbol abgeschieden werden konnte. Von ihren 4 Hydroxylgruppen scheinen im Krotonharz 2 mit Essigsäure verestert zu sein. Nur eine der Acetylgruppen ist verseifbar. Die dritte Hydroxylgruppe ist mit einer höheren Fettsäure von 10–16 C-Atomen verestert, die vierte scheint frei vorzuliegen. Zwei der Hydroxylgruppen im Verseifungsprodukt sind acetylierbar. Im Grundskelett der Formel C₁₉H₂₆O₆ ist daher eine Sauerstoff-Funktion noch ungeklärt.     

‘Passie’ thinking,a hypothesis

Summary Based on observations and on analogical deductions from the organization of the cerebellum, a hypothesis of a passive process of thinking is described. According to it, we try to program the cerebrum for the handling of an idea, regarding its solution we are, however, exposed passively to the brain.     

‘Cystine monosulfoxide’ and related compounds

Zusammenfassung Die früher als «Cystinmonosulfoxyd» beschriebene Verbindung (Thiosulfinat II) verhält sich wie eine äquimolekulare Mischung von Cystin (I) und dem entsprechenden Thiosulfonat (III). Oxydation von Cystin mit Perameisensäure führt, besonders in Gegenwart von HCl, über die Zwischenprodukte Thiosulfonat (III) und Sulfinsäure (VI) zu Cysteinsäure (VII).     

Pensions for ‘Cultivators of Science’

The occasional (and belated) concern of the British Government with science in the nineteenth century is a matter of potential interest to historians of science, yet many previous studies have tended to range over a variety of different aspects of the question. There have been too many vague allusions to financial support as ‘money for science’ in general. It is time that particular parts of the problem were unpacked. For example, the award of money (from the 1820s) to pay a few people of independent means for apparatus was quite distinct from the provision (from the 1830s) of an occasional pension. Even then, to speak of ‘pensions’ uncovers unfortunate ambiguities. For too long science in Britain was regarded as no more than a private hobby for the well-to-do. As late as 1856 an official government statement seemed to make this attitude official. The English attitude to pensions differed remarkably from the French, who established a precedent in the reward of savants, sometimes quoted enviously by British men of science. In 1837 Robert Peel virtually admitted that, in awarding pensions to ‘cultivators of science’, he was following the French practice. It may also be useful to emphasise the contrast between the English (often led by Cambridge professors) and the Scots, mostly from Edinburgh, mainly represented here by Whewell and Brewster, respectively. Babbage had a different role in this story from that usually told. A large part in supporting men of science of modest means could have been played by the British Association for the Advancement of Science but it consistently refused to do so, although it supported an elite among its own members.     

Spectrin and calpain: a ‘target’ and a ‘sniper’ in the pathology of neuronal cells

It is well documented that activation of calpain, a calcium-sensitive cysteine protease, marks the pathology of naturally and experimentally occuring neurodegenerative conditions. Calpain-mediated proteolysis of major membrane-skeletal protein, αII-spectrin, results in the appearance of two unique and highly stable breakdown products, which is an early event in neural cell pathology. This review focuses on spectrin degradation by calpain within neurons induced by diverse conditions, emphasizing a current picture of multi-pattern neuronal death and a recent success in the development of spectrin-based biomarkers. The issue is presented in the context of the major structural and functional properties of the two proteins.Received 7 March 2005; received after revision 22 April 2005; accepted 13 May 2005