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Bidirectional genetic selection for good and poor active avoidance learning in a shuttle box has been carried out in three independent laboratories using remarkably similar discrete-trial training procedures. The resulting strains are known as the Roman High and Low Avoidance (RHA and RLA), the Syracuse High and Low Avoidance (SHA and SLA) and the Australian High and Low Avoidance (AHA and ALA) strains, respectively. An additional unidirectionally selected strain, known as the Tokai High Avoider (THA) strain was developed in Japan using a free-operant Sidman avoidance procedure in a Skinner box. This paper reviews the selection of the Syracuse strains, enumerates the various behavioral and endocrine characteristics of the strains, and compares them to the other similarly selected strains. The behavioral work suggests that genetic selection from diverse breeding stocks has resulted in common characteristics that differentiate the strains in the emotional, not learning, domain. The endocrine data, however, are somewhat at odds. The Syracuse strains differentiate one way with respect to endocrine function, and the Roman strains differentiate in the opposite way. We suggest, therefore, that the endocrine correlates are not tightly linked to the avoidance genotype. Genetic analysis of all of the selected strains for both the avoidance phenotype and the endocrine correlates will be needed to test this hypothesis.

The long-term safety of proposed repositories for nuclear waste is demonstrated by the use of chains of mathematical models describing the performance of the various barriers to radionuclide mobilisation, transport, release into the biosphere and eventual uptake by man. Microbial contamination of such repositories is to be expected, and hence the extent and consequences of microbial activity must also be quantified. This paper describes a modelling approach to determine the maximum microbial activity in the near field of a repository, which can thus be related to maximum possible degradation of performance. The approach is illustrated by application to a proposed Swiss repository for low- and intermediate-level waste (L/ILW), which is immobilised in concrete and emplaced in a marl host rock.

The present paper discusses the factors affecting maximal O2 consumption (VO2max) in hypoxia (4300 m above sea level) along the following lines: 1) In acute hypoxia, the fractional limitation to VO2max imposed by circulatory O2 transport (FQ') is 50%, instead of 70% as in normoxia. This is due to the increase in the blood O2 transport coefficient (beta b) as PO2 decreases, as a consequence of the sigmoidal shape of the O2 dissociation curve of hemoglobin. The remaining 50% is assumed to be equally partitioned between tissue O2 transfer (Ft') and mitochondria O2 utilization (Fm'). 2) In chronic hypoxia, FQ' = 0.45, Ft' = 0.20 and Fm' = 0.35, as a consequence of reduced muscle fiber size and muscle mitochondrial density following acclimatization. 3) The relationship between VO2max and PIO2 in both acute and chronic hypoxia reflects the O2 dissociation curve. 4) Acclimatization to chronic hypoxia does not have the function of preserving VO2max.

For the description of bacterial adhesion phenomena two different physico-chemical approaches are available. The first one, based on a surface Gibbs energy balance, assumes intimate contact between the interacting surfaces. The second approach, based on colloid chemical theories (DLVO theory), allows for two types of adhesion: 1) secondary minimum adhesion, which is often weak and reversible, and 2) irreversible primary minimum adhesion. In the secondary minimum adhesion a thin water film remains present between the interacting surface. The merits of both approaches are discussed in this paper. In addition, the methods available to measure the physico-chemical surface characteristics of bacteria and the influence of adsorbing (in)organic compounds, extracellular polymers and cell surface appendages on adhesion are summarized.

In this paper, we report on the isolation and purification of the oxidase released from the roots ofLactuca sativa seedlings. This is the first time that the release of oxidases from the roots of plants into their rhizosphere has been reported.

A method was devised for the estimation of the configuration on C3 of reserpoides, based on the differences between Rf-values on paper impregnated with formamide and on paper impregnated with formamide containing ammonium formiate.

A blue fluorescent compound was isolated fromMorpho butterfly wings. Based on thin layer chromatographic, UV and CD-spectrophotometric and HPLC analyses, the blue fluorescent compound was identified as L-erythro biopterin. Biopterin is a major component of blue fluorescent pteridines in bothM. sulkowskyi andM. adonis. Pterin and isoxanthopterin can also be detected as minor components in these species. This paper is the first to report the presence of biopterin in butterfly wings.

The subject of heart development has attracted the interest of many embryologists over the last two centuries. As a result, the main morphologic features of the developmental anatomy of the heart are already well established. Although there are still some controversial points, and there is probably much descriptive work yet to be done, emphasis is currently being placed on developmental mechanisms rather than simply on descriptive facts. The availability of new techniques and the overall advances in biological research are placing heart embryology in a new perspective. Today, we do not simply ask whether one or another embryonic structure arises further right or further left; instead, we are studying how cells, tissues, and their microenvironment interrelate at the several levels of biological organization (from the gene upwards) so as to give rise to a mature organ with a distinct shape and well-established functions. This paper attempts to review some of the basic aspects of the developmental anatomy of the heart. Descriptive embryology is used here as a tool. Emphasis is placed on developmental mechanisms, and on the present knowledge of how these mechanisms are related to the structural development of the heart.

This paper briefly reviews the formal properties of the photoperiodic time measurement apparatus of mammals and presents a hypothetical model for the operation of the neural systems responsible for reading and responding to the nocturnal pineal melatonin signal. The primary melatonin readout mechanism is held to be common to all species responsive to melatonin. It seems likely that this mechanism responds to relative changes in the duration and amplitude of the melatonin signal, rather than the absolute levels of melatonin encountered. A series of neural systems which exploit the calendar information provided by the primary readout is envisaged to vary between and within species, depending upon the neuroendocrine response under consideration. Of particular importance is a mechanism for comparing the relative duration of successive melatonin signals. These more complex elements are responsible for phenomena such as the effects of photoperiodic history and photorefractoriness. The brain may be able to encode an accumulated memory of melatonin signals and thereby define longer term intervals within the annual cycle. A series of response elements within the hypothalamus are engaged by the appropriately processed photoperiodic stimuli. For all elements of this model, their anatomical representations are poorly understood or, in certain cases, completely unknown.

In this paper an explanation is given of howPseudomonas (P.) chlororaphis B23 can accumulate so much acrylamide of such high purity. One reason is thatP. chlororaphis B23 exhibits much greater nitrile hydratase activity than amidase activity; the rate of formation of acrylamide through the nitrile hydratase reaction is at least 4000 times higher than its breakdown catalyzed by amidase. Furthermore, acrylonitrile, a powerful nucleophilic reagent, inactivates the active thiol residue of the amidase, whereas nitrile hydratase is not so susceptible to acrylonitrile. Thus acrylamide is produced but not transformed further. In addition, the nitrile hydratase purified fromP. chlororaphis B23 exhibits high resistance to a high concentration of acrylamide. Some other explanations, and the results of evaluation of theP. chlororaphis B23 enzyme as a catalyst for the production of acrylamide are discussed.

In this review I will attempt to identify the circulatory requirements a decapod is likely to encounter and how the heart is controlled to meet these demands. The decapod heart has been designed as an autonomous system endowed with an intrinsic autorhythmic pacemaker ganglion. Muscle fibers are multiply-innervated and capable of producing regenerative action potentials. This vitally important organ has been designed to be nearly fail-safe. Stroke volume is more important than heart rate in determining cardiac output. Stretch sensitivity of the cardiac ganglion and of the myocardium as well as extrinsic nervous and hormonal modulation of the heart can all contribute to changes in stroke volume. It may be advantageous to an animal to switch the circulation between various vascular beds to meet changing perfusion demands. Neuronal and hormonal mechanisms have been identified which exert differential control of the cardioarterial valves, but it is not known whether switching does occur and if so whether these valves participate in the process. Changes in peripheral resistance can also redirect circulatory flow. The circulatory and ventilatory systems demonstrate coordinated rate changes which suggest that the heart is responding to meet changing ventilatory performance requirements. This coupling is controlled both by the hydrostatic pressure pulses generated within the branchial chambers and by common higher level nervous inputs. Comparisons of the cardiovascular systems of crustaceans and molluscs, based on the papers presented at this symposium, are high-lighted.

Different molluscan groups have evolved functionally specialised cardiovascular systems in response to varied behavioural and environmental demands, making the study of cardiovascular regulation in these animals a fascinating area for research. Currently, such research is frustrated by the lack of data on the in vivo performance of these systems, although, where examined, increased cardiac output appears to be accommodated by a change in stroke volume. This paper considers the in vivo regulation of cardiac output, primarily by extrapolating from in vivo experiments, and proposes the following three hypotheses for future study.

The elucidation of methodology (i.e. the approach to be used for the adequate quantification of bioprocesses) is a key area for the understanding and commercialization of biotechnology. This paper intends to fill the gap which has long been observed between the purely empirical approach followed in industrial practice and the mechanistic view used in fundamental biological sciences. According to a more systematic strategy in bioprocess design and development the formal macro-approach represents the basis of all engineering considerations. This fact, however, is not to be taken to mean that the macroscopic is an alternative to the microscopic approach; the two are supplementary, as only mechanistic studies are able to give a detailed interpretation of macroscopic behavior and offer a chance to clarify the black-box by identifying, and thus avoiding, process bottlenecks. This will be demonstrated in the case of baker's yeast processing, where the group of Prof. Fiechter has contributed significantly, and also in the case of antibiotic production processing.

This paper presents the concept of raising seaweeds and other valuable organisms with the aid of huge structures (‘ocean farms’) emplaced in the surface waters of the open oceans. Potential advantages from and difficulties to be expected in realizing the associated technologies are briefly set forth. Much of the published literature pertaining to the concept is referenced and summarized. Wave-powered upwelling of cool, nutrient-rich waters through vertical pipes extending to depths of 100–300 m is indicated as desirable. Technologies are outlined for using the harvested seaweeds to create foods and other valuable products such as animal feeds, fertilizers, fibers, plastics, synthetic natural gas (methane), and alcohol and gasoline fuels. Results from site selection studies and economic analyses are given. It appears that dynamically positioned farms orbiting with the surface current patterns typically found on the ocean will be most cost-effective. The general conclusion is stated that open ocean farming will become economically more feasible as the cheaper fossil fuels and food producing lands of the earth become increasingly consumed in the course of the next century.

The formation of proteinaceous yolk is a main feature during amphibian oogenesis. The main bulk is built up by a process called heterosynthesis. The precursor complex vitellogenin is synthesized in the liver, transported by the bloodstream to the ovary, where the oocytes sequester the material by means of endocytosis. This pathway has been described in detail by many authors. The ultrastructural study of amphibian oocytes indicates on the other hand a small but distinct contribution of the oocyte itself towards yolk formation. This process has been called autosynthesis and starts before the onset of heterosynthetic activities. The cell organelles possibly involved in yolk-recursor and yolk-platelet formation are the nuclear envelope, annulate lamellae, endoplasmic reticulum, Golgi complex, GERL and mitochondria. The aim of this paper is to discuss the data, mainly of ultrastructural nature, so far accumulated during the study of autosynthesis. It is hoped to stimulate more biochemically orientated research in this field.

This paper deals with the fine structure of the fibrillar centres of the nucleolus inAllium cepa cells in ultrathin, sections of in vivo fixed roots. The ultrastructural observations have allowed us to consider each nucleolar fibrillar centre as an active zone in the nucleolar chromatin loop, and to propose a possible model for the organization of the different components of the nucleolus within it.

The spectrum of a chromophore may change as a result of perturbations in its environment. The spectral changes resulting from the perturbation are often followed by measurements at just one or two wavelengths but it is usually no more difficult to collect entire spectra. The problem comes in analysing the data from such a series of spectra. In this paper we will suggest a simple procedure in which the spectrum observed under any particular set of conditions may be considered to consist of the sum of two distinct spectral forms. The method, which is free of any assumptions regarding the quantitative relationship between the perturbation and the extent of spectral change, defines any given spectrum in terms of an apparent molar fraction of the contributing spectral forms. The variation of this apparent molar fraction provides information from which a quantitative relationship can be developed to describe the dependence of the spectral change on the perturbant. The method is illustrated using the model system of phenol red protonation and is applied to the characterization of the binding of azide ions to cobalt-substituted carbonic anhydrase.

Alkaline phosphatase, an ubiquitous enzyme is known to exist in several isozymic forms. At least three different isozymes have now been identified in humans. Alkaline phosphatase isozymes are among the substances synthesized ectopically by a variety of human tumors and many continuous cell lines derived from different cancers have retained the capacity to produce these membrane-located glycoproteins. This paper reviews the identification of alkaline phosphatase isozymes in cultured tumor cells and relates these findings with recent developments concerning these cell membrane located glycoproteins.

Crickets (and many other insects) have two antenna-like appendages at the rear of their abdomen, each of which is covered with hundreds of ‘filiform’ hairs resembling the bristles on a bottle brush. Deflection of these filiform hairs by wind currents activates mechanosensory neurons at the base of the hairs. The axons from these sensory neurons project into the terminal abdominal ganglion to form a topographic representation (or “map”) containing information about the direction, velocity and acceleration of wind currents around the animal. Information is extracted from this map by primary sensory interneurons that are also located within the terminal abdominal ganglion. In this paper, we review the progress that has been made toward understanding the mechanisms underlying directional sensitivity of an identified sensory interneuron in the cricket,Acheta domesticus. The response properties of the cell have been found to depend to a large extent upon the structure of its dendritic branches, which determines its synaptic connectivity with the sensory afferents in the map of wind space and the relative efficacy of its different synaptic inputs.

This paper attempts an update and comment upon some of the topics of chromosome aberration formation which Lea raised in Chapter VI of his classic work 'Actions of Radiations on living Cells'. Only the first nine sections of this chapter are covered, which deal primarily with the qualitative aspects of aberrations, their formation, classification and interrelationships. In commenting upon these topics, pertinent references are made to work with mammalian and human cells. Increased knowledge of the importance of DNA as a fundamental target and the integral part it plays in the complex structure of the chromosome, coupled with cellular techniques not available to these earlier workers necessitate some revision and modification of early ideas. However, inspite of the enormous accumulation of data and ideas since the original work was published in 1946, the foundation that these early workers laid is still very solid. Surprisingly, we are still puzzled by many of the problems that perplexed them.

This paper presents a synopsis of the information available about the pharmacological action of various substances on the cephalopod heart, with special emphasis on the central heart ofSepia officinalis. Threshold concentrations, EC50 values and maximum effective concentrations have been experimentally determined. Studies with various transmitter substances, analogous compounds and antagonists have led to the following picture: Acetylcholine is the natural inhibitory transmitter substance; it acts via receptors with nicotinic properties which can be blocked by d-tubocurarine and α-bungarotoxin. The probable excitatory transmitter system is represented by a noradrenergic innervation. Noradrenaline has a positive inotropic and a positive chronotropic action on in vitro heart preparations. A positive inotropic response can also be evoked by serotonin (5-HT); this effect is not due to stimulation of the catecholamine receptor, as is shown by cross-over experiments with specific blocking agents. Furthermore, a peptidergic receptor system has been described which reacts with the ‘molluscan cardioactive peptide’ FMRF amide most effectively. It is assumed that cardioactive peptides may reach the central heart in the circulating blood; the sites of synthesis and release are still unknown. Possibly the NSV-layer of the vena cava is involved in hormonal cardiovascular regulation processes.

The ionic currents flowing in developing organisms produce weak magnetic fields that can be detected using SQUID magnetometers. The method is non-invasive and dc recording is possible. To date SQUID magnetometers have mainly been used in human studies. The features of the technique are described and the prospects of extending its use to developmental studies are discussed. Feasible instrumental specifications are indicated. A recent SQUID magnetometer investigation of ionic current flow in the developing chick in ovo is summarised as an illustration of the magnetometer method. The paper as a whole argues that magnetometry is a useful alternative or adjunct to electrode-based experiments on the electrophysiology of developing organisms.

Since the founding of the Society of Psychical Research in 1982, psychical researchers have, in each generation, generated research reports which they believed justified the existence of paranormal phenomena. Throughout this period the scientific establishment has either rejected or ignored such claims. The parapsychologists, with some justification, complained that their claims were being rejected without the benefit of a fair hearing. This paper asks the question of how well the best contemporary evidence for psi — the term used to designate ESP and psychokinetic phenomena — stands up to fair and unbiased appraisal. The results of the scrutiny of the three most widely heralded programs of research — the remote viewing experiments, the psi ganzfeld research, and the work with random number generators — indicates that parapsychological research falls short of the professed standards of the field. In particular, the available reports indicate that randomization is often inadequate, multiple statistical testing without adjustment for significance levels is prevalent, possibilities for sensory leakage are not uniformly prevented, errors in use of statistical tests are much too common, and documentation is typically inadequate. Although the responsible critic cannot argue that these observed departures from optimal experimental procedures have been the sole cause of the reported findings, it is reasonable to demand that the parapsychologists produce consistently significant findings from experiments that are methodologically adequate before their claims are taken seriously.

Many persons react to a kind of external agent by unconscious muscular reactions if they move across a place where this agent is supposed to be particularly active. Such places normally coincide with geological discontinuities, such as water veins, mineral ores. Practitioners of this art of detecting claim that the reaction patterns on different levels above ground are identical as vertical projections of the source pattern, this without perceptible attenuation. In some cases the supposed source was believed to have been found up to several hundred meters below ground surface. The statement of perpendicular propagation, which is the subject of this paper, is of prime importance for an approach towards understanding and all kinds of prospecting.

Neurobehavioral genetics endeavors to trace the pathways from genetic and environmental determinants to neuroanatomical and neurophysiological systems and, thence, to behavior. Exploiting genetic variation as a tool, the behavioral sequelae of manipulating these neuronal systems by drugs and antisera are analyzed. Apart from research in rats, this paper deals mainly with the genetically-influenced regulation in mice of exploratory behaviors that are adaptive in novel surroundings and are hippocampally-mediated. Special attention is paid to neuropeptidergic, GABAergic, and cholinergic synaptic functions in the mouse hippocampus. The behaviorally different inbred mouse strains C57BL/6 and DBA/2 show opposite reactions (reductions and increases, respectively, in exploration rates) to peripheral and intrahippocampal injections with agents that interfere with peptidergic, cholinergic, and GABAergic neurotransmission. These findings can be explained by an interdependent over-release of opioids, arrested GABA release, and excess acetylcholine in the hippocampal neuronal network of DBA/2 mice, as compared to C57BL/6 mice where these systems are functionally well balanced. Very similar results have been obtained with the lines SRH and SRL, derived from C57BL/6 and DBA/2, and genetically selected for rearing behavior. Most probably, the opioids act to disinhibit exploratory responses. An additional genetic approach is mentioned, in which four inbred mouse strains and one derived heterogeneous stock are used for estimating genetic correlations between structural properties of the hippocampal mossy fibers and levels of hippocampal dynorphin B, on the one hand, and frequencies of exploratory responses to environmental novelty, on the other.

The pineal gland is a universal feature of vertebrate organization and has been implicated in the control of rhythmic adaptations to daily and seasonal cycles. This paper considers three aspects of pineal function; the generation of a rhythmical endocrine signal (the nocturnal synthesis of melatonin) and the use of the signal in the regulation of circadian and photoperiodic functions. The shape of the nocturnal signal is determined by an interaction of afferent neural control and biochemical processes intrinsic to the pinealocyte. The nature of the effect of the signal upon circadian systems is unclear, and in adult mammals may not be a specific, direct influence upon the entrainment pathways of the oscillator. In the foetus, strong evidence exists for a physiological role of the maternal melatonin signal as a true internal zeitgeber, remnants of which may persist in the adult. Photoperiodic time measurement in adult and foetal mammals is critically dependent upon the melatonin signal. Indirect evidence indicates that several neural systems may be involved in the response to melatonin and consistent with this, a variety of central melatonin binding sites have been identified in the brain and pituitary. The intra-cellular actions of melatonin and the properties of melatonin responsive neural systems have yet to be identified, but in the context of photoperiodic time measurement, it is clear that the neural responses to melatonin are not dependent upon the circadian clock. The two central effects of melatonin; photoperiodic time measurement and circadian entrainment are probably mediated through completely separate mechanisms.

Photon emission from unicellular and multicellular organisms has been a subject of study for many decennia. In contrast to the well-known phenomenon of bioluminescence originating in luciferin-luciferase reactions, low intensity emission in the visible region of the electromagnetic spectrum has been found in almost every species studied so far. At present, the nomenclature of this phenomenon has not crystallized and it is referred to by a variety of names, such as mitogenetic radiation 29, dark luminescence 7, low-level chemiluminescence 20,36, and biophotons 57. Particular attention has been focussed on the relationship between photon emission and the regulation of various aspects of cellular metabolism, although in many cases quantitative data are still lacking. Throughout the history of this field of research the question of a functional biological role of the low intensity emission has been repeatedly raised; this is reflected, for instance, in the heterogeneity of the terms used to describe it. The discussion concerns the possible participation of photons of low intensity in intra- and intercellular communication. This paper reviews literature on the metabolic regulation of low intensity emission, as well as the regulation of photon emission initiated by external light. Furthermore, recent data are discussed with respect to a possible biocommunicative function of low intensity photon emission.

Conditions are discussed which influence Rf1 on thinlayer chromatograms, and directions are given to guarantee good reproducibility. Variance of Rf on thinlayer chromatograms is of the same order of magnitude as on paper chromatograms.

Important facts in connection with the occurrence of N-Nitroso compounds in tobacco smoke have been summarized. This paper reports on analytical methods for the identification of N-Nitroso compounds. The figures known about nitrate content and volatile bases of tobacco, as well as the nitrogen oxides and volatile bases of tobacco smoke as precursors of N-Nitroso compounds, are summarized. The third order reaction of secondary amines with an equimolar mixture of nitric oxide and nitrogen dioxide is a precondition for the formation of N-Nitroso compounds in tobacco smoke. While examining tobacco smoke for N-Nitroso compounds, temperature and time conditions have to be adapted to the natural smoking process. The use of solvent as well as cold traps has to be avoided to exclude the formation of artifacts. Analyses completed under these conditions furnished results of 0.004µg of a mixture consisting of N-Nitroso-dimethylamine and N-Nitroso-pyrrolidine, calculated as N-NO per cigarette. A number of animalexperimental preconditions are still lacking, to judge the biological effects of these extraordinarily small amounts of N-Nitroso compounds.

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 cupolae in the lateral lines of fishes by the present author). Finally some physical arguments are sumarized againstYeagley's theory of bird navigation.

This paper gives a simple outline of those features of the theory of nuclear magnetic resonance that are important to chemical applications. After a short description of apparatus and experimental techniques, there follows a number of representative chemical applications. The possibilities of the method are compared with the information obtained from infra-red spectroscopy.

The author of the paper discusses the influence of tectonic forces on coal which is clearly shown by the structure of deformed coal seams. The succession of incoalation and deformation may be concluded from microscopical investigations. Recent studies on the optical anisotropy of coals show that this phenomenon was either caused by the weight of the overburden or by tectonic stress. The devolatilization of many coals is due to these two kinds of forces and may be used to estimate the approximate folding pressure.

Koschmieder's new thermodynamical theory of tornado formation (1940) makes it probable that a tornado (or a waterspout) develops when a warm air packet rises quickly within the convective mother cloud. In the present paper the three principle cases of conditions are indicated under which supplementary amounts of potential energy necessary to start a “daughter convection” in the cumulo-nimbus cloud can become available in the latter. Supply of moister air from below seems to be at least as important as that one of warmer air. However, the suddenness of the release of the said supplementary energy cannot be explained by the abrupt annihilation of an intercepting layer within the main body of the cumulo-nimbus, for the pre-existence of such a layer is incompatible with the general character of this type of cloud.

The paper deals with recent advances in chemotherapy of tuberculosis. In view of the fact that chemical analysis has shown the lipoid nature of tubercle bacilli and in view of the favorable therapeutic results obtained by treating leprosy with chaulmoogra-acids, the leading idea of many authors was to synthetize lipoidsoluble substances in order to affect the growth of tubercle bacilli. However, the finding that water-soluble substances as Promin inhibit the growth of the microorganisms showed that the idea to use exclusively fatsoluble substances was not necessarily right. Although the therapeutic effects of Promin are not yet particularly encouraging, the experiments made with this substances are useful as they indicate a new direction for research in chemotherapy of tuberculosis. Some of our own experiments with diaminodiphenylsulphone-derivatives are described.

In this paper, written for non-astronomers, are summarized some of the results of a series of spectro-photometric investigations of the continuous spectrum of early-type stars (hot stars) carried on at the Institut d'Astrophysique de Paris; most of the observations were collected at the Jungfraujoch Scientific Station. The determination of the stellar temperatures is one of the main subjects of this work.

Report on recent research on the Quaternary development of flora, vegetation and climate in Northern and Central Europe with schematized diagrams from various papers byFlorschutz, Lona, Szafer and others showing characteristic differences between the older and the newer Interglacials, designed by the present author.

Anesthesia with a large dose of pentobarbital (55 mg/kg, i.p.) caused a sustained decrease in brain temperature (Tb), which was monitored with a probe placed in the midbrain reticular formation. The administration of TRH to the lateral ventricle antagonized this hypothermia. None of the acute surgeries examined in this paper (adrenal-demedullectomy, septal knife cuts, electrolytic lesions of the hypothalamus and midbrain knife cuts) had any essential effect on this antagonism by TRH. These results suggest that centrally-administered TRH exerts its effect on thermoregulation, at least in part, through brain structure(s) caudal to the midbrain.

The paper presents evidence that polymorphonuclear neutrophils upon stimulation with herpesvirus-induced antigens release a material inhibitory to virus infection. The material does not appear to be identical to type I or II interferon.

Species within theD. bipectinata species complex pose problems experimentally because of their morphological similarity. By measuring the number of teeth in each row of the male tarsal sex-comb, an unknown specimen can be allocated to a hybrid or parental group by means of a discriminant function. This paper describes which rows of the sex-comb are the best discriminators for particular comparisons.

This paper reports an experimental demonstration of the ability of sessile marine animals (Balanus balanus L., Crustacea, Cirripedia) to perceive constant hydrostatic pressure. The results suggest the presence inBalanus of a previously unknown sensory system with a tonic response. Such a system may also be present in freely moving animals, but be masked by their locomotor activity.

It is generally believed that antibody-mediated immunosuppression can be only produced in non-primed individuals, and that this applies both to experimental animals and Rh-negative women at risk. However, in this paper it is reported that the additional injection of 0.2 ml of an antiserum to sheep erythrocytes (SE) together with a secondary antigenic stimulus of 10(8) SE into mice, primarily immunized by a tiny dose of 5 x 10(5) SE 28 days before, was capable of producing effective suppression of the secondary immune response.

This paper reports that cortisol at physiological concentrations minimizes the enhancement of human natural killer (NK) cell activity in vitro by immune interferon (IFN-gamma). This effect may be important for the regulation of NK cytotoxicity in vivo.

The paper describes a hexagonal array of nuclear pores in a non-redundant region of the nuclear envelope underlying the basal surface of the rat spermatozoon head. It is concluded that intranuclear material protruding through these pores is the cause of the characteristic rows of circular 'bumps' found in surface replicas of this region.

A purple fluorescent compound was isolated from the integument of scorpion flies. Based on paper chromatographic, UV-spectrophotometric, fluoreometric and HPLC analysis, as well as a chemical color test and various degradation tests, the compound was identified as 7-hydroxybiopterin.

This paper describes experiments designed to evaluate whether the narcotic antagonist naloxone significantly interferes with seizures induced by tetrahydroisoquinolines (TIQs). In these experiments we found that naloxone significantly reduced seizure scores induced by intra-cranially infusing mice with 50 micrograms of the dopamine-derived tetrahydroisoquinoline (TIQ) alkaloid, 6,7-dihydroxy TIQ. These findings support an opioid involvement in the actions of TIQs and may lead to further understanding of opioid-mediated novel excitatory receptors.

The paper deals with the effects of indole-3 acetic acid on the histology of the gonads and their development inDacus dorsalis Hendel (Diptera; Tephritidae). Flies were topically treated with solutions of different concentrations. This treatment effectively reduced the size of gonads when applied to newly-emerged flies. Most severely affected parts were the germinal regions of the gonads. The number of sperm bundles was much reduced in the treated testes as compared to controlled ones.

Larvae of the German cockroach exposed to filter paper impregnated with juvenile hormone (JH) active substance contain, at the middle of the last instar, about one-hundredth of the dose applied to 1 cm2. The amount of metabolized substance rises sharply before and disappears rapidly after the ecdysis into the supernumerary instar.

This paper describes the induction of uterine eosinophilia as well as of deep endometrial edema and increase of uterine wet weight in the immature rat by the catecholestrogens 2-OH-estradiol and 4-OH-estradiol. These effects are thought to be mediated by eosinophils via a specific eosinophil receptor system. 4-OH-estradiol was equipotent with estradiol, whereas the effect of 2-OH-estradiol was significantly weaker.

This paper reports evidence for a hormonal regulation of a new rat serum protein (female specific protein, FP) which is only demonstrable in female rats. Male and female rats were treated with testosterone and estrogen. The FP was assayed with immunological methods. The following results were obtained: 1. In testosterone-treated females the serum level of FP is reduced significantly. 2. In estrogenized males the FP was distinctly demonstrable but not in the control males.

Ecdysterone has been identified in the schistosomiasis vectorBiomphalaria glabrata Say and inHelix aspersa Muller as well as inLymmaea stagnalis L. by chromatography, bioassay, radioimmunoassay, derivatization and by mass spectroscopy. Analysis of the food, faeces and hepatopancreas suggest that the sterol is derived from the diet. The probable function of ecdysterone in relation to calcification of the shell is discussed in this paper.