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Annually since 1989, biannually since 1994 the sites of the Swiss nuclear facilities are surveyed flying the same survey lines by airborne gamma ray spectrometry. The equipment and the data processing software used for those surveys were built and developed at the Institute of Geophysics, ETH Zurich. For mapping the ground radiation around the nuclear facilities, a pixel representation and a modified spectrum dose index (SDI) method are used. In the search for long-term trends, the local dose rates are calculated first and in turn the net dose rates. So far, no change in the radiation levels was detected over the last 13 years outside of the fenced sites of the nuclear facilities and, especially, no artificial radioactivity was present that could not be explained by nuclear weapon tests or by the Chernobyl event.

Summary Dominant white coat colour (W) is a depigmentation syndrome, known in miscellaneous species. When homozygous in the horse (similar in mice), the mutation responsible for the white phenotype is lethal in a very early stage of gestation. It seems, that the action of the dominant white allele is not always fully penetrant, resulting occasionally in spotted look alike offspring. These horses resemble a coat colour pattern known as sabino spotting. So far, it is not known whether dominant white (W) and sabino spotting (S) share a common genetic background. In this study, a pedigree consisting of 87 horses segregating for dominant white (W) was used to genetically localize the horse (W)-locus. Microsatellite ASB23 was found linked to (W), which allowed us to map dominant white to a region on horse chromosome 3q22. Tyrosine kinase receptor (KIT) was previously mapped to this same chromosome region (3q21–22). KIT and its ligand (KITLG) are responsible for the normal function of melanogenesis, haematopoiesis and gametogenesis. So far, sequence analysis of different KIT gene fragments did not lead to new polymorphisms, except for a SNP detected in KIT intron 3 (KITSNPIn3). Additional microsatellites from ECA3q (TKY353 and LEX7), together with KITSNPIn3 allowed us to state more precisely the (W)-mutation. The positional results and comparative functional data strongly suggest that KIT encodes for the horse (W)-locus. Zusammenfassung Die dominant weisse Fellfarbe (W) ist eine Form der Depigmentierung, die bei vielen Spezies auftritt. Beim Pferd wirkt die Mutation fur Dominant Weiss (W) in homozygoter Form (analog zur Maus), bereits in einem sehr fruhen Stadium der Trachtigkeit letal. Es scheint, dass die Wirkung des dominant weissen Allels nicht immer mit vollstandiger Penetranz erfolgt. Dies fuhrt gelegentlich zu Nachkommen mit einer Art Schecken-Fellzeichnung. Solche Pferde sind phanotypisch mit den sogenannten ,,Sabino-Schecken‘‘ vergleichbar. Es ist bis jetzt nicht bekannt ob Dominant Weiss (W) und Sabino-Scheckung (S) einen gemeinsamen genetischen Hintergrund besitzen. Mittels eines Pedigrees aus 87 Pferden, in dem Dominant Weiss (W) segregiert, konnte in der vorliegenden Studie der equine (W)-Locus genetisch lokalisiert werden. Der Mikrosatellit ASB23 erwies sich als gekoppelt mit (W) und ermoglichte die Zuweisung des (W)-Locus auf eine Region von Chromosom ECA 3q22. Das Gen fur den Tyrosinkinaserezeptor (KIT) liegt ebenfalls in dieser Chromosomenregion (3q21–22). Das KIT-Gen ist zusammen mit dem KIT-Liganden (KITLG) verantwortlich fur einen normal funktionierenden Ablauf der Melanogenese, Hamatopoese und Gametogenese. Die direkte Sequenzierung von KIT-Genfragmenten fuhrte bis jetzt zu keinen neuen Polymorphismen, ausser einem SNP in KIT Intron 3 (KITSNPIn3). Mittels weiterer Mikrosatelliten von ECA3q (TKY353 and LEX7) sowie KITSNPIn3 gelang es, die (W)-Mutation genauer zu positionieren. Die vorliegenden Lokalisierungsresultate und vergleichende funktionelle Erkenntnisse deuten stark darauf hin, dass KIT fur den Pferde (W)-Locus kodiert.

During an international intercomparison exercise of airborne gamma spectrometry held in Switzerland 2007 teams from Germany, France and Switzerland were proving their capabilities. One of the tasks was the composite mapping of an area around Basel. Each team was mainly covering the part of its own country at its own flying procedures. They delivered the evaluated data in a data format agreed in advance. The quantities to be delivered were also defined in advance. Nevertheless, during the process to put the data together a few questions raised: Which dose rate was meant? Had the dose rate to be delivered with or without cosmic contribution? Activity per dry or wet mass? Which coordinate system was used? Finally, the data could be put together in one map. For working procedures in case of an emergency, quantities of interest and exchange data format have to be defined in advance. But the procedures have also to be proved regularly.

Annually since 1989, biannually since 1994, the environs (approximately 50 km2) of the Swiss nuclear facilities are surveyed (by helicopters) flying the same survey lines. The equipment and the data processing software used for these surveys were built and developed at the Institute of Geophysics, ETH Zurich. For mapping of man-made radiation at or around nuclear facility sites a pixel representation and the MMGC (man-made gross count) ratio is used. So far no artificial radioactivity that could not be explained by the Chernobyl event (1986) or by earlier nuclear weapon tests was detected outside the fenced sites of the nuclear facilities.

In the present study the effect of the opioid heptadecapeptide nociceptin, also termed orphanin FQ, an endogenous ligand for the orphan receptor named ORL1 (opioid receptor-like 1) receptor, was investigated on [3H]noradrenaline release induced by electrical field stimulation (24 pulses at 0.4 Hz, 200 mA, 0.3 ms duration) in the rat tail artery in the absence and presence of an alpha2-adrenoceptor antagonist, rauwolscine 3 microM. Nociceptin inhibited the electrically-evoked tritiated noradrenaline release in a concentration-dependent manner from rat tail arteries. This inhibitory effect of nociceptin was enhanced in the presence of the alpha2-adrenoceptor antagonist rauwolscine (maximum inhibition by 25% and 50% in the absence and presence of rauwolscine, respectively). At a supramaximal concentration (10 microM), the inhibitory action of DAGO, a selective micro-opioid receptor agonist, was less pronounced than that of nociceptin. The inhibitory effect of nociceptin was counteracted by naloxone benzoylhydrazone (3 microM) which by itself did not change the stimulation-evoked noradrenaline overflow. Naloxone (10 microM), a non-selective opioid receptor antagonist, did not affect the inhibitory effect of nociceptin whereas it abolished that of DAGO. In conclusion, these results suggest that nociceptin modulates noradrenergic neurotransmission by acting on prejunctional ORL1 receptors located on nerve terminals innervating the rat tail artery. They also demonstrate that prejunctional ORL1 receptors interact with prejunctional alpha2-adrenoceptors. The physiological significance of this phenomenon remains to be determined.

In a FACE experiment, one year old alder, ash, beech, and oak seedlings were planted together in tubs containing calcareous sandy alluvial soil with or without a slow release NPK-fertilizer, and exposed to ambient and elevated CO 2 concentrations (360 and 600 μl mol −1 ) for 20 weeks. In addition to the fertilizer, all tubs received 15 N-ammonium nitrate as a marker. Elevated CO 2 significantly increased biomass production in alder, but had no effect on oak and ash. In beech, due to disease and mortality in all treatments, any possible effects were obscured. The addition of fertilizer had no effect on biomass production in alder, but increased production in oak and ash significantly. In oak a treatment synergism may be present. The non-appearance of a synergistic CO 2 and fertilizer effect in alder may be explained by a fertilizer induced reduction of the N-fixing root-nodule biomass concurrent with a switch of the N-assimilation from atmospheric N to soil N supply, as the δ 15 N measurements in the leaves of alder as opposed to oak indicate. Although elevated CO 2 resulted in a significant biomass increase in alder, it did not lead to an appreaciable increase in the proportional presence of the species as measured on total plant biomass in the tub. Increasing the nutrient supply in the soil, however, did lead to appreciable gains in the proportional presence of oak and ash.

The endogenous concentrations of Rb and Cs have been determined in needles of 56 trees (Norway spruce, Picea abies) from eight different sites. Analysis was done by instrumental neutron activation. Concentrations were found to have a very large range (3-28,000 ng Cs/g and 1-190 micrograms Rb/g). The values on a given site have a tendency toward a log-normal distribution. There is a significant correlation between Rb and Cs, but the correlation is not linear. The concentrations of both elements are a function of the needle age. They decrease smoothly, approaching a constant value, when going from needle age class 1 to 5. It is shown that one algebraic function describes this biodynamic behavior on all sites and at all concentration levels. The function and its parameters are discussed.

The endogenous concentrations of Sc, La, Ce, Sm, Eu, Tb, Yb, and Lu were determined by neutron activation analysis in up to five successive needle age classes of Norway spruce (Picea abies). Trees from nine sites over different bedrocks were sampled individually. Concentration values found are generally much lower than those reported in the literature. This is attributed to the careful removal of any aerosols or soil particles from the needle surface prior to analysis. The concentration of each element increases linearly with the needle age class, i.e., the accumulation can be characterized by just one parameter, the yearly increment. This pattern is followed at small as well as at large concentrations. The accumulation behavior of the investigated elements is identical to that of Si. The relative concentrations of the rare earth elements (REE) in the needles are similar to those in the earth crust. There are significant correlations between the individual REE and between Sc and La.

The outdoor radiation exposure of the population in Switzerland from external sources results from cosmic background as well as from natural and artificial ground radiation. The geographical distribution of these components and of the total dose rate are represented on maps consisting of 2 kmx2 km grid cells. The average dose rate on Swiss territory outdoors is 147 nSv/h (1.29 mSv/a). The distributions are then related to the population density distribution by GIS application. The population is exposed to an average dose rate of 108 nSv/h (0.95 mSv/a) per capita which is just below the threshold for man-made dose rate given by national regulation. The lower value (relative to the country average 147 nSv/h) arises from the fact that most of the population lives north of the Alps where the lithology is dominated by rocks of relatively low radioactivity and where the cosmic radiation is low relative to the Alps.

Recurrent intravenous leiomyoma extending to the right heart chambers is extremely rare. A large range of surgical techniques and approaches (i.e. two-step procedure, hypothermia and circulatory arrest) have been previously described. We report a recent case where the tumour was excised in a one-step procedure under normothermic cardiopulmonary bypass. This report associated to a comprehensive literature review allows us to discuss the role of pre-operative assessment and to propose refinement of surgical techniques according to the anatomy of the tumour.

GenHevac B Pasteur is a recombinant hepatitis B vaccine derived from a mammalian cell line and containing HBs as well as pre-S2 antigens. Its immunogenicity was compared to that of the plasma-derived vaccine Hevac B Pasteur in a population primovaccinated 5.5 years earlier with four injections of the same plasma vaccine. The booster injection with either GenHevac or Hevac was administered to 295 subjects with residual anti-HBs titres below 500 IU/l (group 1: 0–9; group 2: 10–99; group 3: 100–499 IU/l). After four weeks, GenHevac had induced higher anti-HBs responses than Hevac in all groups, particularly among the low responders of group 1. Response to the vaccine occurred earlier with GenHevac. Mean anti-pre-S2 production was moderate in all groups for both vaccines (GenHevac: 60 IU/l; Hevac: 31 IU/l) and was not found in the 32 subjects who produced less than 100 IU/l anti-HBs. The results of the present study indicate that GenHevac is at least as immunogenic as Hevac.

Experiments were designed to study the interaction between prejunctional alpha 2-adrenoceptors and both adenosine and opioid receptors at the postganglionic sympathetic nerve endings innervating the tail artery of the rat. Segments of this vessel were preincubated with [3H]-noradrenaline and then perfused/superfused with [3H]-noradrenaline-free medium. Their perivascular nerves were field stimulated with standard stimulation parameters: 24 pulses at 0.4 Hz, 0.3 ms, 200 mA. In some experiments, the stimulation parameters were adjusted in order to obtain similar reference release values despite the presence of a first release-modulating drug. The adenosine agonist 5'-N-ethylcarboxamidoadenosine (NECA; 0.3-10 mumol/l) and [D-Ala2,MePhe4,Glyol5]enkephalin (DAGO; 0.3-10 mumol/l) depressed the stimulation-evoked overflow of tritium in a concentration dependent manner. The release-inhibiting effect of both NECA and DAGO was enhanced in the presence of the alpha 2-adrenoceptor antagonist rauwolscine (3 mumol/1) while it was attenuated in the presence of the alpha 2-adrenoceptor agonist 5-bromo-6-[2-imidazolin-2yl-amino]-quinoxaline (UK-14,304; 0.1 mumol/l). These changes occurred both at standard and adjusted stimulation parameters. These results demonstrate that the prejunctional adenosine A1- and opioid mu-receptors interact with the prejunctional alpha 2-adrenoceptors. The level at which these interactions take place (receptors themselves or transduction mechanisms) as well as the physiological significance of the phenomenon remain to be determined.

In order to find out whether beta-endorphin (beta-E) is involved in the development of hypertension, we performed two series of experiments. Firstly, spontaneously hypertensive rats (SHR) and their normotensive Wistar Kyoto controls (WKY) were submitted to ether stress. Plasma concentrations of beta-endorphin-like immunoreactivity (beta-EI), adrenocorticotropin (ACTH) and alpha-melanotropin (alpha-MSH) were measured by radioimmunoassay. The basal concentration of beta-EI was similar in WKY and SHR, whereas WKY had higher levels of ACTH and lower levels of alpha-MSH than SHR. In both strains acute stress enhanced the plasma concentration of beta-EI to the same extent and with a similar time-course. The increase of plasma beta-EI coincided with a rise in ACTH but not alpha-MSH. Gel chromatography of beta-EI revealed that plasma extracts contain similar amounts of beta-lipotropin- (beta-LPH) and beta-E-sized immunoreactive components, and that acute stress elevated both forms of beta-EI. Secondly, isolated tail arteries of SHR and WKY were perfused and field stimulated with two pulses at 1 Hz. beta-E depressed stimulation-evoked vasoconstriction with the same potency in both strains. Thus, basal and stress-induced levels of beta-EI did not differ in SHR and WKY. Moreover, in the tail artery of both strains the sensitivity of presynaptic opioid receptors towards beta-E was almost identical. If the beta-E sensitivity of these receptors in other arteries of WKY and SHR is also similar a major role of the circulating peptide in the development of hypertension is rather unlikely.

Isolated tail arteries of rats were perfused and field-stimulated every 2 min with 2 pulses at 1 Hz. Different opioid peptides depressed the contractile responses to stimulation; their concentration-response curves showed a maximum at about 40% inhibition. The rank order of potency of the peptides was β-endorphin (IC50 = 97 nmol/1) ≅ BAM-22P > FK-33824 > DAGO > [d-Ala2,d-Leu5]-enkephalin ⩾ metorphamide > dynorphin A-(1-13) ≅[Met5]enkephalin. All these substances have in common a certain activity at opioid μ-receptors, although the enkephalins are preferential δ-, and the dynorphins preferential κ-agonists. However, the selective δ-agonist [d-Pen2,l-Pen5]enkephalin was ineffective at up to 10 μmol/l, and the κ-agonists ethylketocyclazocine and U-50488 acted only at concentrations higher than 3 μmol/l. Whereas the effects of β-endorphin, DAGO and [d-Ala2,d-Leu5]enkephalin could be reduced by the μ-preferential antagonist naloxone, the effects of ethylketocyclazocine and U-50488 were not changed. The δ-selective antagonist ICI 174864 did not influence the action of [d-Ala2,d-Leu5]enkephalin. Naloxone in a concentration (1 μmol/l) which nearly abolished the effect of DAGO 3 μmol/l, slightly enhanced responses to stimulation. Neither β-endorphin nor DAGO influenced vasoconstriction evoked by the application of noradrenaline or adenosine triphosphate; U-50488 reduced it. In arteries preincubated with [3H]noradrenaline DAGO depressed, whereas naloxone enhanced the tritium overflow and vasoconstriction evoked by field stimulation (0.4 Hz, 24 pulses every 14 min). In addition, naloxone antagonized the effect of DAGO. We suggest that the axon terminals of postganglionic sympathetic neurones in the rat tail artery possess β-endorphin-sensitive opioid receptors of the ɛ-type. The activation of these receptors by exogenous or endogenous opioids inhibits the release of the neuroeffector transmitter.

Dopamine (0.5-100 muM) as well as apomorphine (1-100 muM) were found to be potent stimulators of adenylate cyclase in homogenates of rabbit retina. When compared with the dopamine-effect at 10 muM, half-stimulation was also obtained in response to noradrenaline or adrenaline, whereas isoprenaline or phenylephrine were ineffective. Furthermore, the dopamine-induced production of cyclic AMP wab blocked by chloropromazine and haloperidol. These data would suggest the occurrence of a specific "dopamine receptor" in the retina of the rabbit.

The superconducting phase YBa2Cu4O8 ('124') differs from YBa2Cu3O7 ('123') in having a double, instead of single, Cu–O chain running parallel to the b axis. It was first observed as a lattice defect in partly decomposed 123 powders1, and then as an ordered defect structure in inhomogeneous 123 thin films2,3, but has not up to now been synthesized in bulk. As part of a systematic study of the pressure–temperature–composition phase diagram of pseudo-binary Y–Ba–Cu–O systems at high oxygen pressure4,5, we have determined the approximate field of thermodynamic stability of the 124 phase. Here we report synthesis of the phase in bulk at 400 bar O2 and 1,040 °C. In agreement with previous measurements in thin films, the transition temperature is 81 K. Unlike the 123 compound, the oxygen content in 124 is thermally stable up to 850 °C, which may prove important for applications.