The effect of continuous exposure to low frequency electric fields on three generations of mice: a pilot study.

Mice were allowed to mate, gestate, deliver and rear their offspring for 3 successive generations while being continuously exposed to 60 Hz electric fields. Mice exposed to vertical electric fields exhibited decreased body weights at 35 days postpartum and increased mortality rates for 3 successive generations. Mice exposed to horizontal electric fields exhibited decreased body weights for 2 successive generations.     

Power frequency electric field induces biological changes in successive generations of mice

Summary Electromagnetic fields arising from the electrical power system are pervasively present in the environment. To help evaluate their public-health risk we raised 3 successive generations of mice in a low-strength, 60-Hz electric field. We found that the field caused an increased mortality in each generation, and, altered body weights in the 3rd generation.This work was supported by the National Institute of Environmental Health Sciences, Department of Health, Education and Welfare, the Environmental Protection Agency, and the Veterans Administration.     

Macronuclear response ofParamaecium multimicronucleatum tol-lysine

Summary A strain ofParamaecium multimicronucleatum was exposed to a medium containingl-lysine; the concentrations of the amino acid were 0.1%, 0.5% and 1.0% for different sets of experiments. In these two latter concentrations, the macronucleus of the ciliate broke down into innumerable small fragments, the microspheres. The micronuclei remained inert. The microspheres left the body of paramaecium as cell-free, self-duplicating entities constituted of DNA and RNA and enveloped by a protein coat. They had no nuclear membrane and they resembled the prokaryotes. Grown in culture medium with 0.1% horse serum, the microspheres transformed into small amoebae having typical eukaryotic features. These amoebae maintained a typical cyst-trophic cycle during the successive sub-cultures; they had no similarity with the paramaecia.     

Mescaline: Its effects on learning rate and dopamine metabolism in goldfish (Carassius auratus)

Summary The pharmacological action of mescaline on goldfish was studied with the Bitterman-Agranoff shock-avoidance test. In short term experiments with high mescaline doses an increase in learning rates was observed. Similar results were obtained with apomorphine andl-dopa. However, when the fish were exposed to smaller mescaline doses (or to fluphenazine) for 3 days, their ability to avoid electric shock was reduced. Apparently, mescaline induced a release of dopamine which stimulated central dopaminergic systems. Subsequently, MAO destroys the liberated dopamine. Thus, the ensuing dopamine deficit appears to be responsible for the marked changes in behavior in the chronic experiment.This work was supported in part by research grants from the National Eye Institute (EY No. 00313) and the National Institute of Mental Health (MH No. 20020), and by the Sterling Morton Charitable Trust Fund.     

Antiinflammatory reaction associated with murine L1210 leukemia

Summary Mice bearing L1210 leukemia did not show impaired humoral or cellular immune response to antigenic stimulation during the early stage of the tumor, and a depressed response was noted only in the terminal stage. L1210 cells were shown to suppress inflammatory reaction in vivo.Supported in part by USPHS research grant No.5-01-RR05-352-12, and by theIndependent Order of Foresters, San Bernardino District 3208. We acknowledge the valuable assistance ofJudith Johnson andJames Tan in this project. Histopathological examination byDick H. Koobs is appreciated.     

Na*-independent binding of [3H] muscimol to a membrane fraction of the brains of normal and dwarf mice

Summary Although their body weights were decreased by about 77% and their brain weights by about 30%, high-affinity [³H] muscimol binding to a cerebral membrane fraction was not altered in hereditary pituitary dwarf mice. Marked changes in the level of pituitary growth-associated hormones do not appear to be associated with a change in cerebral GABA-receptors.Supported by a UNESCO/IBRO Fellowship. Permanent address: Semmelweis University Medical School, 1st Institute of Biochemistry, Budapest, Hungary.     

Na+ independent binding of [3H] muscimol to a membrane fraction of the brains of normal and dwarf mice

Although their body weights were decreased by about 77% and their brain weights by about 30%, high-affinity [3H] muscimol binding to a cerebral membrane fraction was not altered in hereditary pituitary dwarf mice. Marked changes in the level of pituitary growth-associated hormones do not appear to be associated with a change in cerebral GABA-receptors.     

An unwelcome discovery: The pole effect in the electric arc, a threat to early 20th century precision spectrometry

In late 1912, Fritz Goos at the Hamburg Physikalisches Staatslaboratorium discovered a systematic dependency of arc-spectra wavelengths on the length of the electric arc used and on its electric parameters, such as, for instance, the current employed. In early 1913, at Heinrich Kayser's better-equipped physical laboratory in Bonn, Goos was able to confirm these effects using a large concave Rowland grating. He was able to establish that variations of between 3 mm and 10 mm in the length of the arc produced wavelength differences of up to 0.02 Å violet shift and -0.007 Å redshift respectively. Further inquiry also revealed a dependency of the wavelength on the region of the arc selected for spectrometric observation. All these surprising effects were soon collectively named pole effect.As is shown in this paper, the pole effect threatened the validity of the results of the entire research tradition of high-precision spectroscopy which, around 1910, had excelled in establishing several internally coherent systems of wavelength assignments. These wavelength catalogues had been established by spectroscopists such as Heinrich Kayser, Paul Eversheim and their co-workers in Bonn, by August Herman Pfund in Baltimore, and by Charles Fabry and Henri Buisson in Marseille under the aegis of the International Union for Co-Operation in Solar Research. They had all produced locally consistent, homogeneous systems of wavelengths with estimated errors sometimes smaller than 0.001 Å. However, long before 1913, strange non-local inconsistencies had emerged between these systems that were of much greater magnitude than the estimated error. The discovery of the pole effect opened up the possibility that variations in the arc parameters used in the measurements, which the different teams had hitherto not specified, were responsible for the systematic differences, in their respective sets of measurements, coming to up to 0.025 Å.This paper explores the interrelations between local knowledge production, the strategies for the establishment of local coherence, and the ways in which the community of physicists and spectroscopists handled a possible threat to this coherence after 1913. Around 1930, a general agreement was reached about the physical cause of the pole effect, namely Stark effects, caused in turn by intermolecular electric fields of ions in the arc. Much before 1930, however, the community had already succeeded in standardizing the instrumentation used in high-precision spectrometry and had conformed its research practice to such an extent that from 1917 on the pole effect could be routinely circumvented in high-precision spectrometry and interferometry. Thus, experimentation along with its instrumentation, indeed had a life of its own, independent of the many unsuccessful efforts to explain the pole effect theoretically.     

Bacterial endotoxin and impaired fetal development

Summary Small doses ofE. coli endotoxin given to pregnant mice on the 13th day of pregnancy caused only a mild maternal illness but induced resorption of approximately half the number of fetuses in each mouse. The remaining live fetuses developed normally and showed no evidence of retarded growth or malformations. The weights of their placentas and maternal spleens increased significantly. Endotoxin given on the 6th day of pregnancy caused a small reduction in fetal weights.Acknowledgments. I am indebted to Mrs.Heather Sandison for technical assistance and to Mr.M. J. R. Healy for statistical examination of the results. Dr.A. B. G. Lansdown kindly advized on the interpretation of histological findings.     

Testosterone changes the electric organ discharge and external morphology of the mormyrid fish, Gnathonemus petersii (Mormyriformes)

Effects of silastic and pellet methyltestosterone implants on the waveform of the electric organ discharge of the weakly electric African mormyrid, Gnathonemus petersii, were investigated. Within seven days of implantation, the duration of the discharge increased dramatically while the associated peak power frequency of the Fourier spectrum decreased in all treated fish. By day 35, hormone-treated fish exhibited up to five-fold increases in EOD duration, as well as multiple discharges and variations in the shape of the positive phase of the discharge. Testosterone treatment also changed body morphology, making immature and adult female fish resemble adult males.     

Thiamine diphosphatase in rat small intestine

Summary TDPase is located mostly in the proximal portion of the small intestine and its activity, like that of ALPase, decreased markedly in thiamine deficiency. The decreased enzyme activities were restored after thiamine or vitamin D₃. Kinetic and other studies of the purified enzyme indicated the identity of the two enzymes.Acknowledgment. We thank Miss.T. Yagura and Miss.H. Kuroda for technical assistance.     

Eine modifizierte Kapillarmethode zur Messung osmotischer Werte von Pflanzensäften und Lösungen

Summary The capillary method ofBarger for determining molecular weights can also be used for measuring osmotic values of vegetable saps. The method is improved by using capillaries which are closed at one end, siliconcoated inside, and the drops filled in by means of capillary pipettes.     

Autoradiographische Untersuchungen zur Frage des Eiweißstoffwechsels in den lymphoretikulären Organen

Summary The size of protein-metabolism in lympho-reticular organs (spleen and lymph-nodes) is examined by means of autoradiography. Mice, rats and rabbits were fed with S³⁵-labelled thioamino-acids. The density of the silver grains in the autoradiographs allows a statement about the size of proteinmetabolism in relation to thioaminoacids. From this point of view the problem of the germinal centres and marginal zones of theMalpighian follicles, the «Basophileninseln» in the red pulp and the endothel of the splenic sinuses is discussed.     

On the time course of thyrotropin suppression by high doses of thyroid hormones

Summary Basal and stimulated TSH decreased progressively. Basal TSH was suppressed below the detection limit of 0.4 U/ml after 74 h in 2 of the T₃ and all of the T₄ treated indiduals. At this time, in both groups 3 individuals could be significantly stimulated by TRH (about 5% of the pretreatment stimulation). There was no significant difference in the time course of suppression obtained by T₃ or T₄, though plasma T₃ levels in the T₄ treated group were considerably lower.Supported by the Deutsche ForschungsgemeinschaftThe excellent technical assistance of MissM. Knöpfle, MissU. Neun and Mr.G. Magin is gratefully acknowledged.     

Differential effects of lipids on the osmotic fragility of lysosomes

Summary The effect of a wide range of concentrations of oleic acid, oleyl alcohol and oleic acid methyl ester on lysosomal stability has been studied under both hypotonic and isoosmotic medium conditions. Both oleic acid and oleyl alcohol exhibited a biphasic interaction pattern with lysosomes; stabilizing at low concentrations and labilizing at high concentrations. Lysosome labilization by the ester required an initial lag period.Acknowledgment. We should like to thank Mr.David Ginzburg for the assistance he gave us during the 3 months he spent at our department as a summer student.     

Mechanische Festigkeit als Elektroneneffekt

Summary TheBrinell hardness ofHume-Rothery alloys depends on their electron concentration in the same way as do catalytic activation energy and electric resistivity. A wave-mechanical theory of hardness, based on the more or less total completion of theBrillouin-zones, is proposed.     

J. Zaragosa's centrum minimum,an early version of barycentric geometry

Summary Using the properties of the Centre of Gravity to obtain geometrical results goes back to Archimedes, but the idea of associating weights to points in calculating ratios was introduced by Giovanni Ceva in De lineis rectis se invicem secantibus: statica constructio (Milan, 1678). Four years prior to the publication of Ceva's work, however, another publication, entitled Geometria Magna in Minimis (Toledo, 1674), 2 appeared stating a method similar to Ceva's, but using isomorphic procedures of a geometric nature. The author was a Spanish Jesuit by the name of Joseph Zaragoza.Endeavouring to demonstrate an Apollonius' geometrical locus, Zaragoza conceived his idea of centrum minimum — a point strictly defined in traditional geometrical terms — the properties of which are characteristic of the Centre of Gravity. From this new concept, Zaragoza developed a theory that can be considered an early draft of the barycentric theory that F. Mobius was to establish 150 years later in Der barycentrische Calcul (Leipzig, 1827).Now then, whereas Ceva's work was rediscovered and due credit was given him, to this day Zaragoza's work has remained virtually unnoticed.     

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.     

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.     

Duration of hornet sleep induced by ether anesthesia is curtailed by exposure to sun or UV irradiation

Irradiation of hornets anesthetized by diethyl ether curtails their sleep duration from the ordinary 20–30 min to a mere 2–3 min. This effect on sleep is dependent on the intensity of the sun irradiation or, when exposed to monochromatic UV at 366 nm, on the duration of the irradiation. Of the various hornet cuticular areas of the body, the yellow cuticular areas of the abdominal segments are the most sensitive to the treatment. We assume that the cuticles of both live and dead hornets act as a converter of light to electric energy.