Heaps of moles? – Mediating macroscopic and microscopic measurement of chemical substances

In this paper I take a close look at the SI base quantity “amount of substance”, and its unit, the mole. The mole was introduced as a base unit in the SI in 1971, and there is currently a proposal to change its definition. The current definition of the mole shows a certain ambiguity regarding the nature of the quantity “amount of substance”. The proposed new definition removes the ambiguity, but at a cost: it becomes difficult to justify treating amount of substance as having its own dimension, and hence its own unit, the mole. I argue that the difficulties with amount of substance result from its role as a mediator between macroscopic and microscopic scales. To understand why amount of substance might have its own dimension, we need to connect amount of substance to mass, contra current proposals to separate them.     

Should scientific realists embrace theoretical conservatism?

A prominent type of scientific realism holds that some important parts of our best current scientific theories are at least approximately true. According to such realists, radically distinct alternatives to these theories, or theory-parts, are unlikely to be approximately true. Thus, one might be tempted to argue, as the prominent anti-realist Kyle Stanford recently did, that realists of this kind have little or no reason to encourage scientists to attempt to identify and develop theoretical alternatives that are radically distinct from currently accepted theories in the relevant respects. In other words, it may seem that realists should recommend that scientists be relatively conservative in their theoretical endeavors. This paper aims to show that this argument is mistaken. While realists should indeed be less optimistic of finding radically distinct alternatives to replace current theories, realists also have greater reasons to value the outcomes of such searches. Interestingly, this holds both for successful and failed attempts to identify and develop such alternative theories.     

A new type of antigen induced by chemical linkage ofMycobacterium tuberculosis and γ-globulin

Zusammenfassung Mit Hilfe derPauly'schen Diazo-Reaktion wird humanes -Globulin an humanpathogene, virulenteMycobacterium tuberculosis-Stämme (M) gekoppelt. Das Zustandekommen der chemischen Bindung wurde mit gefärbten Präparaten, elektronenmikroskopischen und immunelektrophoretischen Untersuchungen der Bakterien bewiesen. Die mit-Globulin gekoppeltenM haben ihre Virulenz eingebüsst. In den Versuchstieren wurden Antikörper sowohl gegen -Globulin als auch gegenM gebildet. Durch ersteres wurde das Allergisierungsvermögen vonM gesteigert.     

The secret of truffles: A steroidal pheromone?

Summary The steroid 5-androst-16-en-3-ol has a pronounced musk-like scent. It is a major constituent of the pheromone of the boar. It occurs also in axillary sweat of men but is devoid of androgenic activity. The presence of this steroid has been demonstrated in truffles (Tuber melanosporum) both by radioimmunoassay and by gas chromatography-mass spectrometry in quantities of 40–60 ng/g fresh material. This offers an explanation for the ability of pigs to detect truffles growing as deep as 1 m under ground.     

The oxidative metabolism ofα-chlorohydrin and the chemical induction of spermatocoeles

Summary -Chlorohydrin (I) is oxidatively metabolized to -chlorolactic acid (III) and oxalic acid (IV). Deposition of calcium oxalate within the renal tubules is responsible for the toxic effects of-chlorohydrin and a similar action on the epididymis or epididymal blood vessels could initiate the formation of spermatocoeles from this and other male antifertility agents.     

A place for pragmatism in the dynamics of reason?

In Dynamics of Reason Michael Friedman proposes a kind of synthesis between the neokantianism of Ernst Cassirer, the logical empiricism of Rudolf Carnap, and the historicism of Thomas Kuhn. Cassirer and Carnap are to take care of the Kantian legacy of modern philosophy of science, encapsulated in the concept of the relativized a priori and the globally rational or continuous evolution of scientific knowledge, while Kuhn’s role is to ensure that the historicist character of scientific knowledge is taken seriously. More precisely, Carnapian linguistic frameworks, guarantee that the evolution of science proceeds in a rational manner locally, while Cassirer’s concept of an internally defined conceptual convergence of empirical theories provides the means to maintain the global continuity of scientific reason. In this paper it is argued that Friedman’s Neokantian account of scientific reason based on the concept of the relativized a priori underestimates the pragmatic aspects of the dynamics of scientific reason. To overcome this shortcoming, I propose to reconsider C.I. Lewis’s account of a pragmatic priori, recently modernized and elaborated by Hasok Chang. This may be considered as a first step to a dynamics of an embodied reason, less theoretical and more concrete than Friedman’s Neokantian proposal.     

Berthelot's anti-atomism: A ‘matter of taste’?

The influential French chemist Marcelin Berthelot spoke against the use of Dalton's atomic theory and Avogadro's hypothesis in the second half of the nineteenth century. This paper argues that Berthelot conceded that atomism might be acceptable as a system of conventions, but he feared the power of such conventions in constructing a realistic picture of atoms which was not warranted empirically. Equally, Berthelot's anti-atomism was a last-ditch effort to assert the place of chemistry within the tradition of natural history and to deny the possible reduction of chemical science to the laws of nineteenth-century physics.     

Is chemical memory transfer due to shock or behavior training?

Summary A memory transfer experiment was performed to determine whether the transfer effect is due to stress associated with the foot shock or to the specific behavioral training. Recipient animals were significantly better in the jump-out testing than either the shock-control recipients or the control recipients, but the shock-control recipients performed significantly better than the control recipients. Foot shock has an effect on the transfer phenomena but is not responsible for the entire effect.     

Is chemical memory transfer due to shock or behavior training?

A memory transfer experiment was performed to determine whether the transfer effect is due to stress associated with the foot shock or to the specific behavioral training. Recipient animals were significantly better in the 'jump-out' testing than either the shock-control recipients or the control recipients, but the shock-control recipients performed significantly better than the control recipients. Foot shock has an effect on the transfer phenomena but is not responsible for the entire effect.     

A simple synthesis of (E)-3-formylbut-2-enenitrile,and its use as a precursor of isotope-labelled zeatin and (±) dihydrozeatin

Summary (E)-3-Formylbut-2-enenitrile (4) is synthesized in 2 steps by reacting pyruvaldehyde dimethylacetal and acetonitrile in the presence of sodium methoxide, followed by acid hydrolysis to give 58% overall yield on distillation. The aldehyde4 can be stepwise and selectively reduced to (E)-3-hydroxymethylbut-2-enylamine (7a) in 37% total yield or exhaustivelyb reduced in 1 step to (±)-4-hydroxy-3-methylbutylamine (6) in 46% total yield. Compound7a and6 can be condensed with 6-chloropurine to give zeatin and (±)dihydrozeatin respectively. This provides a readily accessible method for isotope-labelled zeatin and its derivatives at side chain.Contribution No. 1064, Alberta Research CouncilProcess for the Preparation oftrans-3-formylbut-2-enenitrile S. Chen and J. MacTaggart, patent applicatioin registered in Canada and the United States of America.Acknowledgment. The author thanks Mr J. M. MacTaggart and Mrs C. M. Goulet for valuable experimental assistance and Dr R. M. Elofson for helpful discussions.     

A rediscovery of scientific collections as material heritage? The case of university collections in Germany

The purpose of this article is twofold: on the one hand, we present the outlines of a history of university collections in Germany. On the other hand, we discuss this history as a case study of the changing attitudes of the sciences towards their material heritage. Based on data from 1094 German university collections, we distinguish three periods that are by no means homogeneous but offer a helpful starting point for a discussion of the entangled institutional and epistemic factors in the history of university collections. In the 19th century, university collections were institutionalized and widely recognized as indispensable in research and teaching. During the 20th century, university collection became increasingly marginalized both on an institutional and theoretical level. Towards the end of the 20th century, the situation of university collections improved partly because of their reconsideration as material heritage.     

Forecast Combination for Euro Area Inflation: A Cure in Times of Crisis?

The period of extraordinary volatility in euro area headline inflation starting in 2007 raised the question whether forecast combination methods can be used to hedge against bad forecast performance of single models during such periods and provide more robust forecasts. We investigate this issue for forecasts from a range of short‐term forecasting models. Our analysis shows that there is considerable variation of the relative performance of the different models over time. To take that into account we suggest employing performance‐based forecast combination methods—in particular, one with more weight on the recent forecast performance. We compare such an approach with equal forecast combination that has been found to outperform more sophisticated forecast combination methods in the past, and investigate whether it can improve forecast accuracy over the single best model. The time‐varying weights assign weights to the economic interpretations of the forecast stemming from different models. We also include a number of benchmark models in our analysis. The combination methods are evaluated for HICP headline inflation and HICP excluding food and energy. We investigate how forecast accuracy of the combination methods differs between pre‐crisis times, the period after the global financial crisis and the full evaluation period, including the global financial crisis with its extraordinary volatility in inflation. Overall, we find that forecast combination helps hedge against bad forecast performance and that performance‐based weighting outperforms simple averaging. Copyright © 2017 John Wiley & Sons, Ltd.     

Presence of hsp65 in bacterial extracts (OM-89): A possible mediator of orally-induced tolerance?

Heat shock proteins (HSP) have been implicated in rodent models of autoimmunity, particularly arthritis, and there is suggestive though inconclusive evidence that they may also play a role in human autoimmune disease. The simplest hypothesis is based on molecular mimicry due to the amino-acid sequence homology between mammalian and microbial HSP. Recently OM-89, an extract of several strains ofEscherichia coli, has shown some efficacy in the treatment of rheumatoid arthritis (RA) when taken orally. Using species-specific antibodies, we show here that OM-89 contains the 65 kDa HSP (hsp65), while hsp65 was not detected in another bacterial extract containing other microorganisms, includingStaphylococcus aureus (OM-85). We suggest that if the human homologue of hsp65 is a relevant target antigen in the human disease, the efficacy of the preparation could be due to induction of oral tolerance or to switching the Th1 response towards Th2. Alternatively, even if the human hsp65 is not a target molecule in RA joints, OM-89 may evoke bystander suppression of joint inflammation via induction of TGF-secreting effector cells. These hypotheses should be tested in further studies.