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The total cross section for $\ensuremath{\omega}$ production in the $\mathrm{pp}\ensuremath{\rightarrow}\mathrm{pp}\ensuremath{\omega}$ reaction has been measured at 5 c.m. excess energies from 3.8 to 30 MeV. The energy dependence is easily understood in terms of a strong proton-proton final state interaction combined with a smearing over the width of the state. The ratio of near-threshold $\ensuremath{\varphi}$ and $\ensuremath{\omega}$ production is, to within relatively large uncertainties, consistent with the predictions of a simple one-pion-exchange model. The degree of violation of the Okubo-Zweig-Iizuka rule is similar to that found in the ${\ensuremath{\pi}}^{\ensuremath{-}}p\ensuremath{\rightarrow}n\ensuremath{\omega}/\ensuremath{\varphi}$ reactions.

The polarized d d -> alpha X reaction at beam energies close to the eta threshold shows very strong structure in the missing mass corresponding to the ABC enhancement. The deuteron tensor analysing power A_yy, and the slope of the vector analysing power A_y with respect to angle, have been measured for this reaction around the forward direction. Both signals are small, and their variations with the alpha-particle momentum are in broad agreement with a theoretical model in which each pair of nucleons in the projectile and target deuterons undergoes pion production through the NN -> d pi reaction.

The total cross section of the pp -> pp eta' reaction has been measured at two energies near threshold by detecting the final protons in a magnetic spectrometer. The values obtained are about a factor of 70 less than for the corresponding eta production, in good agreement with the predictions of a one-pion-exchange model.

The cross section and tensor analysing power t_20 of the d\vec{d}->eta 4He reaction have been measured at six c.m. momenta, 10 < p(eta) < 90 MeV/c. The threshold value of t_20 is consistent with 1/\sqrt{2}, which follows from parity conservation and Bose symmetry. The much slower momentum variation observed for the reaction amplitude, as compared to that for the analogous pd->eta 3He case, suggests strongly the existence of a quasi-bound state in the eta-4He system and optical model fits indicate that this probably also the case for eta-3He., LaTeX, uses elsart.sty, 10 pages, 3 Postscript figures, Submitted to Physics Letters B

The production of η′ (958) and φ (1020) mesons has been studied very close to threshold in the inclusive p d → 3 He X reaction. The complicated phase space acceptance problem caused by rapidly changing kinematics close to threshold has been carefully treated. The measured averaged squared amplitudes |f|2 at threshold are 0.9 and 2.4 nb/sr for the η′ and φ meso Our results are in remarkable agreement with predictions of a two-step model, which uses existing π− p → n X data as input. However the ratio of φ to ω production seems at variance with naive expectations based on the Okubo-Zweig-Iizuka rule.

Backward [omega](782)-meson production in the [ital pd][r arrow][sup 3]He[omega] reaction has been measured from threshold up to an [omega] center-of-mass momentum of 625 MeV/[ital c]. The averaged squared amplitude rises rapidly from threshold to a maximum value of about 70 nb/sr at 180 MeV/[ital c], decreasing thereafter. This striking behavior, which is very similar to that already observed for [pi][sup [minus]][ital p][r arrow][ital n][omega], may be caused by a final-state interaction between the pions from the [omega] decay and the recoil nucleus.

The total cross section for \ensuremath{\eta} production in deuteron-deuteron interactions has been measured at four different kinetic energies, from 0.7 MeV to 3.7 MeV above threshold. The squared amplitude is consistent with a constant value of \ensuremath{\Vert}f${\mathrm{\ensuremath{\Vert}}}^{2}$=(24.6\ifmmode\pm\else\textpm\fi{}1.2\ifmmode\pm\else\textpm\fi{}1.7) nb/sr close to threshold (14${\mathit{p}}_{\mathrm{\ensuremath{\eta}}}$40 MeV/c). Assuming that the ${\mathrm{\ensuremath{\pi}}}^{0}$-\ensuremath{\eta} mixing reaction mechanism is dominant, this result allows a prediction of (d\ensuremath{\sigma}/d\ensuremath{\Omega}${)}_{{\mathrm{\ensuremath{\pi}}}^{0}}$=(8.3\ifmmode\pm\else\textpm\fi{}0.5 \ifmmode\pm\else\textpm\fi{}0.6) pb/sr for the cross section of the isospin-forbidden reaction d+d\ensuremath{\rightarrow}\ensuremath{\alpha}+${\mathrm{\ensuremath{\pi}}}^{0}$ at the \ensuremath{\eta}-threshold energy.

This study correlates whole organ measurements of intracellular calcium concentration ([Ca(2+)](i)) with hormone-induced (epinephrine, vasopressin) changes of liver functions (glucose release, K(+) balance and bile flow). [Ca(2+)](i) was measured in the isolated perfused rat liver using the sensor Fura-2 and applying liver surface fluorescence spectroscopy. The technique was improved by (i) minimizing biliary elimination of the sensor by employing a rat strain deficient in canalicular organic anion transport (TR(-) mutation) and (ii) by correcting for changes of interfering intrinsic organ fluorescence that was shown to depend on the oxidation-reduction state (NAD(P)H content) of the organ. Epinephrine (50 nM) elicits an instantaneous peak rise of [Ca(2+)](i) to approx. 400 nM, followed by a sustained elevation that depends on the presence of extracellular Ca(2+). The rise of [Ca(2+)](i) coincides with initiation of glucose release, transient K(+) uptake, and transient stimulation of bile flow. Vasopressin (2 nM) exerts qualitatively similar effects. The transient rise of bile flow is attributed to Ca(2+)-mediated contraction of the pericanalicular actin-myosin web of hepatocytes.

Effects of insulin-like growth factor I (IGF-I) and insulin on glucose and potassium fluxes were examined by measuring transhepatic glucose and potassium balance in isolated perfused rat livers. At 1 nM, both IGF-I and insulin decreased basal glucose release by approximately 64% (P < 0.05). Adrenaline (epinephrine)-stimulated glucose release (42.6 +/- 4.5 micromol/g of liver within 30 min) was inhibited (P < 0.05) by approximately 32 and approximately 52% during IGF-I and insulin exposure, which was accompanied by reduced cAMP release (-71 and -80%, P < 0.05). IGF-I- and insulin-induced reduction of glucose release only decreased during calcium-free perfusion, but not during inhibition of phosphoinositide 3-kinase by wortmannin. Both IGF-I and insulin induced net potassium uptake, while insulin also attenuated the response to adrenaline. In conclusion, IGF-I causes (i) insulin-like inhibition of hepatic glycogenolysis, even at low, nanomolar concentrations, which is associated with decreased cAMP release, reduced in the absence of Ca(2+), but not mediated by phosphoinositide 3-kinase, (ii) reduction of adrenaline-induced glycogenolysis and (iii) net potassium uptake under basal conditions.

For the parity-violation experiment at the Mami cw electron accelerator facility at the University of Mainz, we need a stable polarized electron source able to deliver a current >150 μA with polarization >60%. We develop the Orsay polarized electron source SELPO as an injector for MAMI. SELPO source based on a flowing helium afterglow is now operating in a high voltage platform. The terminal will be tested completely at Orsay and is foreseen to be installed at MAMI before the end of this year. Recent results obtained with an array of capillaries to generate the helium flow and a longitudinal spin direction are described.

Double differential cross sections d 2 σ/dpdΩ have been measured for π + and K + emitted around midrapidity in d + A and α + A collisions at a beam kinetic energy of 1.15 GeV/nucleon. The total π + yield increases by a factor of about 2 when using an alpha projectile instead of a deuteron whereas the K + yield increases by a factor of about 4. According to transport calculations, the K + enhancement depends both on the number of hadron-hadron collisions and on the energy available in those collisions: their center-of-mass energy increases with increasing number of projectile nucleons.

Double differential K$^+$ cross sections have been measured in p+C collisions at 1.2, 1.5 and 2.5 GeV beam energy and in p+Pb collisions at 1.2 and 1.5 GeV. The K$^+$ spectrum taken at 2.5 GeV can be reproduced quantitatively by a model calculation which takes into account first chance proton-nucleon collisions and internal momentum with energy distribution of nucleons according to the spectral function. At 1.2 and 1.5 GeV beam energy the K$^+$ data excess significantly the model predictions for first chance collisions. When taking secondary processes into account the results of the calculations are in much better agreement with the data.

We report here the results of the calibration of the polarimeter POMME for vector polarized deuterons at an energy of 1.8 GeV. The results show that inclusive deuteron-carbon scattering has substantial vector analyzing power even at this high energy. The results obtained on two analyzers, carbon, which is generally used and a lighter material, paraffin, are found to be similar.

This experimental program focuses on meson production near threshold via the reaction p + d → 3He + X. The incident beam energy and the 3He momentum are matched in such a way that the mesons are produced at rest in the c.m. system. Clear signals can be observed at the ω,ή, K \(\bar K\) and φ thresholds.

Only few reports exist about the occurrence of brittle nails. We examined 1,584 persons with respect to the incidence of this anomaly. The patients were from five different groups: outpatients of a dental clinic, blood donors, residents of an old people’s home, patients of a clinic for internal diseases and patients of a general practice. Approximately 20% of the subjects examined had brittle nails. Women suffered from brittleness of nails much more frequently than men (27 vs. 13%) with a ratio of men to women from 1:1.6 to 1:7 depending on age. 44% of the subjects affected (75% of the females, 25% of the males) had tried one or several treatments but only 26% believed in their curative effect. The market for the therapy of brittle nails in the FRG is estimated to be between 2 and 4 million people.

We examined nail samples of 27 adult patients suffering from brittle nails and 15 persons without nail disorders with respect to the content of trace elements. The analysis by atomic absorption spectroscopy disclosed the following values. In parentheses values of healthy nails. Ca 44.9 ppm +/- 25.0 (53.6 ppm +/- 22.5), Mg 182.4 ppm +/- 128.0 (183.1 ppm +/- 83.2), Al 25.6 ppm +/- 10.3 (33.0 ppm +/- 20.5), Cu 7.9 ppm +/- 3.0 (7.9 ppm +/- 2.7), Zn 80.9 ppm +/- 34.5 (85.0 ppm +/- 34.9), Fe 53.9 ppm +/- 24.5 (45.7 ppm +/- 24.4). Comparing the two groups no significant differences could be found.

Near threshold two pion production via the reaction pd → 3 Heπ + π − was measured kinematically complete with the MOMO experiment at COSY. A remarkable deviation of the obtained two pion invariant mass spectra from phase space as well as a predominant back to back and sidewise emission of the two pions was observed.