A chromosome mutation affecting the number of nucleoli inXenopus borealis Parker

Résumé L'examen cytologique de la descendance de 2Xenopus borealis révéla 50% d'individus dotés de noyaux à 1 et 2 nucléoles (situation normale) et 50% à 1, 2 et 3 nucléoles. Le caryotype de ces derniers démontra la présence de 3 organisateurs nucléolaires, au lieu de 2, l'origine de l'élément supplémentaire relevant d'une translocation réciproque entre 4 et 7.

---

---

Supported by a grant (No. 3.60.68) from the Fonds national suisse de la Recherche Scientifique and the George and Antoine Claraz donation.

---

Unpublished research in this laboratory has shown thatXenopus laevis borealis (Parker) is a species on its own right and we propose to name itXenopus borealis (Parker).

---

Material collected byFischberg andKobel, who express their gratitude to the Fisheries and Game Dept. of Kenya for permission to collect frogs of the genusXenopus.

---

Acknowledgments. The authors wish to thank Mrs.J. Tymowska and MissE. Ackermann for their technical advice; they are grateful to Mr.J. Jackson, MissM. C. Payot, MissL. Ricard and Mr.P. Grutter for their assistance and useful help.     

Sterility and lethality in crosses involving two translocation heterozygotes of the Germay cockroach, Blatella germanica (L.).

Productivity in crosses involving two independent reciprocal translocations in Blattella germanica are reported. Lethal effects alone could not account for the reductions in hatch since completely unproductive crosses occurred frequently. The latter are attributed to the inability of reduced numbers of viable embryos to force open the egg case. The implications for genetic control of the joint dominant effects from embryonic trapping and translocation semisterility are discussed.     

Locomotory energetics in a marsupial (Antechinomys spenceri) and a rodent (Notomys alexis)

Summary Steady state oxygen consumption was compared in a rodentNotomys alexis and a marsupialAntechinomys spenceri. The marsupial was found to diverge from predicted eutherian energetic patterns.N. alexis appears to use energy storage as a significant part of the step cycle before becoming bipedal. Aerobic scope and heat storage during running are similar in both species.We thankP. Baverstock, C. Watts andH. Aslin for the use of theAntechinomys, Ms.B. Whaite for assistance. Supported by Grants from the Nuffield Foundation, the Ingram Trust and the Flinders University Research Committee to RVB.     

Canescin,ein mit Reserpin wirkungsgleiches Alkaloid ausRauwolfia canescens

Summary Canescine or 11-Desmethoxyreserpine, a new alkaloid isolated byStoll andHofmann fromRauwolfia canescens has been submitted to a comparative pharmacological study with Reserpine. The circulatory effects obtained with these two alkaloids can practically not be distinguished from each other. Like Reserpine also Canescine exhibits a sedative action and produces pupillary constriction.     

Antischistosomal and some toxicological properties of a nitrodiphenylaminoisothiocyanate (C 9333-Go/CGP 4540)

Summary A procedure to enhance the schistosomicidal effectiveness in vivo of an isothiocyanate derivative and some of its antischistosomal properties are reported. Determinations of the effects of this compound on tissue thiol levels and on highly sensitive bacterial tester strains have indicated that its mutagenic potential is of a low order and that the latter is decreased further after reduction of the host's intestinal bacterial flora.Acknowledgments. Supported, in part, by grants No. AI-08022 and No. GM-16492 from the National Institutes of Health, and No. 274-0063 (JHU No. 1) from The Edna McConnell Clark Foundation. We wish to express our sincere appreciation to Dr.H. Striebel and Dr.F. Kradolfer of Ciba-Geigy for providing us with the isothiocyanate derivative and with information about its biological activities, and to Dr.H. van der Schalie and to Dr.H. Blankespoor of the Museum of Zoology, University of Michigan, for supplying us with mice infected with 3 strains ofS. japonicum (under contract No. N01-AI-42504, NIH).     

Newton's early computational method for dynamics

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.     

Newton and the classical theory of probability

Summary Probabilistic ideas and methods from Newton's writings are discussed in § 1: Newton's ideas pertaining to the definition of probability, his probabilistic method in chronology, his probabilistic ideas and method in the theory of errors and his probabilistic reasonings on the system of the world. Newton's predecessors and his influence upon subsequent scholars are dealt with in §2: beginning with his predecessors the discussion continues with his contemporaries Arbuthnot and De Moiver, then Bentley. The section ends with Laplace, whose determinism is seen as a development of the Newtonian determinism.An addendum is devoted to Lambert's reasoning on randomness and to the influence of Darwin on statistics. A synopsis is attached at the end of the article.Abbreviations PT abridged Philosophical Transactions of the Royal Society 1665–1800 abridged. London, 1809 - Todhunter I. Todhunter, History of the mathematical theory of probability, Cambridge, 1865 To the memory of my mother, Sophia Sheynin (1900–1970)     

Die physikalische Kieme der Wasserinsekten

Summary The air stores carried by a number of aquatic insects have: a) a hydrostatic function (Brocher, Oortwijn-Botjes, Thorpe, andCrisp); b) the function of an oxygen store (Ege, de Ruiter et al.) and c) the function of a physical gill (Strauss-Durckheim, Ege, etc.). The fact that oxygen is taken up from water with the aid of an air bubble was demonstrated forNotonecta by comparing the life time of insects with and without physical gill (while replenishing the oxygen store from the air was prevented) byEge, and forCorixa byPopham, whileVlasblom determined the oxygen uptake from water with and without air bubble forNotonecta, Naucoris, Corixa, Sigara andNepa. Nepa andSigara can take up considerable quantities of oxygen by cutaneous respiration.During the summer, the gill function of the air store ofNotonecta andNaucoris is of importance only when a water current passes along the animal, caused by ventilation movements of the legs (de Ruiter et al.). At low temperatures, however, the metabolic rate is so low that in many instances the physical gill provides the oxygen required without ventilation movements.An apparatus for the simultaneous determination of oxygen uptake from air and water (Wolvekamp andVlasblom) gave results that provided a means of evaluating the importance of the physical gill function.In some cases, the air store, although in direct contact with the water, does not need to be replenished. InAphelocheirus andElmis, the negative pressure in the bubble, caused by oxygen consumption and the diffusing out of part of the nitrogen, is compensated for by the mechanical resistance of a feltwork of thin hairs and the surface tension of the boundary layer of the water (Thorpe andCrisp). In the African beetle,Potamodytes, the unprotected air bubble is permanent because the strong river currents produce a lowered pressure around the animal according toBernoulli's principle (Stride).     

Reflexine,a new indole alkaloid ofRauwolfia reflexa

Summary Reflexine, a new indole alkaloid, has been isolated from the leaves ofRauwolfia reflexa Teijsm. and Binn. From spectral studies, chemical reactions and correlation with seredamine, reflexine is shown to be its C-17 epimer (IV).Grateful thanks are accorded to ProfessorR. H. Thomson, Dr.R. T. Brown, Dr.Nitya Nand and Dr.S. C. Pakrashi for spectral measurements. Financial assistance from CCRIMH, New Delhi, and UGC, New Delhi, are also thankfully acknowledged.     

Der Mathematiker Abraham de Moivre (1667–1754)

Summary Before examining de Moivre's contributions to the science of mathematics, this article reviews the source materials, consisting of the printed works and the correspondence of de Moivre, and constructs his biography from them.The analytical part examines de Moivre's contributions and achievements in the study of equations, series, and the calculus of probability. De Moivre contributed to the continuing development from Viète to Abel and Galois of the theory of solving equations by means of constructing particular equations, the roots of which can be written in the form . He also discovered the reciprocal equations. In the course of this work de Moivre discovered an expression equivalent to (cos +i sin ) ⁿ =cos n +i sin n and, following Cotes, he succeeded in expressing the nth roots of unity in trigonometric form.In the theory of series, de Moivre developed a polynomial theorem encom-passing Newton's binomial theorem and, in particular, a theorem of recurrent series useful in the calculus of probability.The demands of the calculus of probability led de Moivre to an approximation for the binomial coefficients for large values of n. The interaction between de Moivre and James Stirling, particularly in regard to the asymptotic series for log (n!), is treated at length. This work supplied the foundation for de Moivre's limit theorem for the binomial distribution.The calculus of probability, which occupied him from 1708 onward, became in time ever more the center of de Moivre's inquiries. Proceeding from contemporary collections of gambling exercises, de Moivre, by introducing an explicit measure of probability for the so-called Laplace experiments, found the beginnings of a theory of probability. De Moivre expanded the classic application of probability calculus to games of chance by addressing himself to the problem of annuities and by adopting Halley's work with its conception of Probability of life. De Moivre was the first to publish a mathematically formulated law for the decrements of life derived from mortality tables.

---

Abkürzungen a.a.O. am angegebenen Ort = Verweis auf das nach Verfassern alphabetisch geordnete Literaturverzeichnis. Eine vor a.a.O. in runden Klammern angegebene Zahl kennzeichnet die entsprechende Nummer der im Literaturverzeichnis aufgeführten Arbeiten eines Autors. - AC Ars conjectandi = Jakob Bernoulli (4) a.a.O. - AE Acta Eruditorum - a.S. alter Stil⁴⁷ - BM Bibliotheca Mathematica - DMV Deutsche Mathematiker-Vereinigung - JL Journal Literaire - MA Miscellanea Analytica, London 1730 - n.S. neuer Stil⁴⁷ - PT Philosophical Transactions of the Royal Society of London - r.F. rekurrente Folge - r.R. rekurrente Reihe - SMA Miscellaneis Analyticis Supplementum, London 1730 - v. veröffentlicht (nur im Briefverzeichnis verwendet) Prof. Dr. Kurt Vogel zum 80. Geburtstag Vorgelegt von J. E. Hofmann     

Die Reizschwelle der Sinnesorgane als physikalisches Problem

Summary A survey is given of recent work on physical aspects of sensory processes. The reasoning which leads to the generally recognized view that one rod of the retina is excited by only one quantum of light is given in par. II. In par. IIIa summary is given of the papers byHecht andVan der Velden on the number of rods which must be struck in order to obtaina sensation of light. Par. III describes the role of the quantum character of light at higher intensities (de Vries), where it sets a limit to intensity discrimination and visual acuity. The influence of Brownian movement on the process of hearing is discussed in par. VI. It is found that the Brownian movement of the inner ear is close to the threshold actually observed (de Vries), whereas the Brownian motion of the air at the eardrum (seeSivian andWhite) is below the audible threshold. The role of the Brownian movementin the sense cells is described in par. VII; the results are used for an analysis of the mechanism of hearing (see alsode Vries); evidence is obtained that electric voltages are generated in the tectorial membrane (the well-known cochlear microphonics) and that they play an important part in the mechanism of energy transfer to the sense cells (similar voltages were also derived from the cupolæ in the lateral lines of fishes by the present author). Finally some physical arguments are sumarized againstYeagley's theory of bird navigation.     

Die Stabilitätenreihenfolge der stereoisomeren Hydrindan-und Hydrindanon-Verbindungen

Summary The stability orders for severalcis/trans epimeric hydrindanones and 8-methyl-hydrindanones are shown in a qualitative manner. Starting with the geometry of cyclopentane and cyclohexane changes of Bayer and Pitzer strain existing in the two isomeric bicyclo (4:3:0) nonane systems are discussed. The influences of an angular methyl group (estimated by the simple empirical method evaluated byTurner) and of two new conformational effects (alkyl ketone effects) induced by replacing a methylene group by a carbonyl group are taken into account.     

Antiviral substances in starfish

Zusammenfassung Eine Gruppe von teilweise chemisch charakterisierten Verbindungen, welche die Vermehrung des Influenza-Virus in Huhnembryo-Test verhindern, wurde aus den SeesternenAsterias forbesi, Asterias pectinifera undAcanthaster planci isoliert.

---

---

This research was supported by the N.S.F. Sea-Grant Program. The author thanks Dr.H. W. Younken Jr. and Dr.L. R. Worthen for their encouragement and suggestions throughout this work. Thanks are also due to Dr.Hashimoto, Tokyo University, and Dr.Yasumoto, Tohoku University, for the specimen ofAsterina pectinifera, and Dr.B. M. Branham, University of Hawaii, forAcanthaster planci sample. The antiviral test was carried out by Dr.O. Liu, Northeast Shellfish Sanitation Research Center, D. H. E. W., Narragansett, Rhode Island, to whome the author expresses his sincere gratitude.     

Effect of ACTH on the zona reticularis of the rat adrenal cortex: An ultrastructural stereologic study

Summary The effects of ACTH on the rat adrenalzona reticularis were investigated by stereologic methods. It was found that thezona reticularis cell responsiveness to ACTH is similar to that of thezona fasciculata elements. This excludes that thezona reticularis of the adult rat can only function as the site of destruction of worn-out elements migrating from the adrenal outer zones.Acknowledgment. We wish to thank Mr.G. Gottardo for his skilled technical assistance. This work was partly supported by a contract with the CNR No. C.T.73.00663.04.     

Cytogenetic studies with atrazine (2-chloro-4-ethyl-amino-6-isopropylamino-s-triazine) on plants

Zusammenfassung Untersuchungen anVicia faba- undHordeum-Wurzelspitzen sowie anSorghum-Pollenmutterzellen ergeben keine Hinweise für eine zytogenetische Wirksamkeit des Triazin-Herbizides Atrazin in Pflanzen.

---

---

The authors are greatly indebted to Dr.U. Leuthold for his help in conducting the experiments. The excellent technical assistance of Mrs.J. Determeyer and MissD. Kempf is gratefully acknowledged.     

Aspects biochimiques des herbicides à base de triazines

Summary The triazine herbicides are potent inhibitors of theHill reaction, resembling the phenylureas, acylanilides and carbamates. The inhibition of the photosynthesis by the triazines is the most obvious explanation for their mode of action in plant metabolism. Besides this there are also effects on light independent reactions where the effective concentrations are higher than those inhibiting the photosynthesis. Particularly, a positive influence of the triazines on the uptake of the nutrients by the roots was noted. Changes in the nitrogen metabolism of the plants, due to increased uptake of nitrate from the medium, result in a higher content of organic nitrogen in the plants.Several enzyme systems in plants and in micro-organisms are influenced by the triazine herbicides. Until now, the mechanism of action has not been elucidated.Concerning the phenomenon of the selectivity of the triazine herbicides, several factors may be responsible. The different abilities of the plant species to metabolize the herbicide and to translocate it to the active centres in the cells are significant from the biochemical point of view.

---

---

Une partie de ce travail a été présentée lors de la 463^e séance de la Biochemical Society, Aberystwyth, septembre 1966.P. W. Müller, Biochem. J.101, 1P. (1966).Nous tenons à exprimer nos remerciements àR. Truan qui a bien voulu se charger de la version française ainsi qu'àG. Dupuis pour sa participation à la mise au point du manuscrit.     

Nuclear numbers in encysted dormant embryos of differentArtemia salina populations

Summary The number of nuclei in dormant cysts from world-wide populations of the brine shrimp,Artemia salina (L.) was determined. These nuclear numbers proved to be quite constant considering the diversity of geographical localities, ploidies, and modes of reproduction represented by these populations. We believe this constancy indicates a tight coupling between the development and dormancy of these embryos. Chromosome counts onArtemia from Jamnagar, India indicated this population to be triploid.We wish to thank Dr.T. Iwasaki for supplying cysts of the Aio Machi population, Dr.C. Barigozzi for cysts from Sete and Comacchio, and Dr.G. Stephens for cysts from Jamnagar. This research was supported by a grant from the U.S. National Science Foundation No. GB-40199.     

Some metabolic disorders affecting the carotenoid-linked haemolymph proteins inRhynchosciara americana (Diptera,Sciaridae)

Summary Disorders in the carotenoid metabolism are proposed to explain the absence of the yellow and violet or only the violet carotenoid-linked proteins from the haemolymph of someR. americana larvae. The lack of only the yellow chromoprotein is considered to be due to a failure in the biosynthesis of its apoprotein.Supported by Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) and Conselho Nacional de Pesquisas (CNP_q). W.R.T. and A.G. de B. are indebted to Prof.F. J. S. Lara for advice, encouragement and for laboratory facilities. We thank Mr.A. Malavasi for collecting larvae in nature, Mrs.R. M. Zanelato for larvae culture and MissI. L. Jorge for typing.     

Trypsin activity in the midgut ofSarcophaga ruficornis andMusca domestica (Diptera: Insecta)

Summary The pH and temperature for the optimum activity of trypsin from the midgut ofSarcophaga ruficornis andMusca domestica was 7.5 and 8.0 respectively and 50°C. The enzymic activity increased with the increase in incubation period and enzyme concentration.Thanks are due to Prof.R. Rakshpal for guidance.     

Conformational control of bond migration in the D-homo rearrangement of 17-hydroxy-20-keto steroids

The concept of conformational control of bond migration in the trnsition state to theD-homo-annulation of 17-hydroxy-20-keto steroids appears to provide a unified rationale for the observed phenomena.Contribution from Merck & Co., Inc., Rahway, N. J., presented before the North Jersey Section of the American Chemical Society byN. L. Wendler as part of a lecture entitledStereochemical Effects Attending D-Ring Rearrangements in Steroids, February 3, 1959.