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Published online 7 August 2007; Low-spin states of $^{182}Ir$ were populated through the $\beta^+/EC$ decay of $^{182}Pt$. Two strong $E2$ transitions were observed for the first time: a 25.7keV transition in $^{182}Ir$ and a 34.0keV transition in Re of probable mass A = 178. Spin and parity, $I^\pi = 3^+$, are firmly assigned to the $^{182}Ir$ ground state (g.s.). For the excited states, the parity is established and the spin determined or restricted. These assignments support most of the interpretations of the level structure previously suggested. The systematics for the known $5^+ \to 3^+$ transitions in $\pi h_{9/2} \bigotimes ν 1/2^-[521]$ bands is presented. Using a semi-microscopic two-quasiparticle axial-rotor coupling model, particle configurations have been attributed or suggested for most of the coupled states lying at low energy in $^{182}Ir$.

Laser spectroscopy measurements have been performed on neutron-deficient and stable Ir isotopes using the COMPLIS experimental setup installed at ISOLDE-CERN. The radioactive Ir atoms were obtained from successive decays of a mass-separated Hg beam deposited onto a carbon substrate after deceleration to 1kV and subsequently laser desorbed. A three-color, two-step resonant scheme was used to selectively ionize the desorbed Ir atoms. The hyperfine structure (HFS) and isotope shift (IS) of the first transition of the ionization path $5d^{7}6s ^{2}^{4}F_{9/2} \to 5d^{7}6s6p ^{6}F_{11/2}$ at 351.5nm were measured for $^{182-189}$Ir, $^{186}Ir^{m}$ and the stable $^{191,193}$Ir. The nuclear magnetic moments μI and the spectroscopic quadrupole moments Qs were obtained from the HFS spectra and the change of the mean square charge radii from the IS measurements. The sign of μI was experimentally determined for the first time for the masses 182≤A≤189 and the isomeric state $^{186}Ir^ m$ . The spectroscopic quadrupole moments of $^{182}$Ir and $^{183}$Ir were measured also for the first time. A large mean square charge radius change between $^{187}$Ir and $^{186}Ir^g$ and between $^{186}Ir^m$ and $^{186}Ir ^g$ was observed corresponding to a sudden increase in deformation: from β2 ≃ + 0.16 for the heavier group A = 193, 191, 189, 187 and 186m to β2 ≥ + 0.2 for the lighter group A = 186g, 185, 184, 183 and 182. These results were analyzed in the framework of a microscopic treatment of an axial rotor plus one or two quasiparticle(s). This sudden deformation change is associated with a change in the proton state that describes the odd-nuclei ground state or that participates in the coupling with the neutron in the odd-odd nuclei. This state is identified with the π3/2+[402] orbital for the heavier group and with the π1/2-[541] orbital stemming from the 1h _9/2 spherical subshell for the lighter group. That last state seems to affect strongly the observed values of the nuclear moments.

The γ-ray de-excitations following the β-decay of 83Ga and the β-n decay of 84Ga have been studied. The radioactive species were produced using the PARRNe on-line mass-separator installed at the IPN Orsay Tandem accelerator. Two γ-lines were attributed to 83Ge with the aid of β-γ and γ-γ coincidences. The Z identification of the γ-lines was provided by time analysis of a buid-up/decay cycle. The excited levels of 83Ge can be explained by the coupling of the single neutron state ν2d 5/2 to the first 2+ excitation of the 82Ge core.

Low-spin states of 184Au have been studied using the β+/EC decay of 184Hg. γ-ray and conversion-electron singles spectra were recorded with 184Hg mass-separated sources. For γ-γ-t and X-γ-t coincidence measurements, mercury nuclei were produced in the 148Sm + 40Ar reaction and transported by a He-jet system. The electron spectra were recorded from 184Hg sources produced at ISOLDE. A level scheme of 184Au including 48 transitions is proposed. The experimental results are interpreted in the frame of a semi-microscopic axial-rotor-plus-two-quasiparticle model developed in the context of the HF+BCS approximation.

High-resolution measurements of low-energy conversion electrons have been performed in odd and odd–odd nuclei with masses around A=182. The experimental setup, a magnetic spectrograph coupled to a specific tape transport system, is described. Three experiments have been performed and the main results are presented.

Laser spectroscopy measurements have been performed on neutron deficient iridium isotopes. The hyperfine structure and isotope shift of the optical Ir I transition 5d76s24F9/2 → 5d76s6p 6F11/2 at 351.5 nm have been studied for the 182–189Ir, \(^{186} {\text{Ir}}^\user1{m} \) and 191,193Ir isotopes. The nuclear magnetic and quadrupole moments were obtained from the HFS measurements and the changes of the mean square charge radii from the IS measurements. A large mean square charge radius change between 187Ir and 186Ir and between \(^{186} {\text{Ir}}^\user1{m} \) and \(^{186} {\text{Ir}}^\user1{g} \) has been observed.

Laser spectroscopy measurements have been carried out on very neutron-deficient isotopes of Au, Pt and Ir, produced as daughter elements from a Hg ISOLDE beam. For these transitional region nuclides, the hyperfine structure (HFS) and isotope shift (IS) were measured by Resonance Ionization Spectroscopy (RIS). Magnetic moments μ, spectroscopic quadrupole moments Qs and changes of the nuclear mean square charge radius δ〈rc 2〉along isotopic series have been extracted. For some results, a detailed comparison with theoretical predictions is presented.

Isotope shift and hyperfine structure measurements have been performed on the short lived184Au nucleus using the COMPLIS apparatus installed at ISOLDE. The charge radius change and the magnetic and quadrupole moments of both isomeric and ground states have been deduced. The184Au ground state appears to be slightly more deformed than the isomeric state.

The controlled clinical trial reported here is part of a multicenter clinical and basic research project, sponsored by the German Federal Minister of Science and Technology, directed by a standing commission of the president of the Max-Planck-Gesellschaft, and coordinated by the Max-Planck-Institut fur Biochemie, Munchen. Overall, 249 patients with rheumatoid arthritis (RA) were enrolled by 16 participating hospitals. In addition to NSAID treatment, patients were randomly given either interferon gamma (IFN-γ) or placebo. In the IFN-γ group, 107 patients were evaluated and in the control group, 116 patients were evaluated. The response rate after 3 months of treatment, according to joint pain indexes, was significantly higher in the IFN-γ group with an error probability of 1%. IFN-γ was able to reduce the quantity of corticosteroids administered. Compared with the control group, the IFN-γ group benefited considering all parameters measured. Most important side effects were transient fever and transient influenza-like symptoms; all other adverse events were comparable in both groups.

In a multicenter placebo-controlled double-blind randomized clinical study, 91 patients with rheumatoid arthritis were given 28 days' treatment with recombinant interferon-gamma (50 micrograms daily for 20 days, then 50 micrograms each second day up to day 28, given by subcutaneous injection). The aim of the study was to provide a methodologically clear demonstration of the efficacy of treatment with interferon-gamma, using criteria that could be handled by statistical tests. Evaluatable documentation was available for 79 patients, of whom 40 were treated with the active compound. The principal criterion for the statistical evaluation of the therapeutic success was improvement of the Ritchie "joint pain index" or Lansbury "joint pain index" by at least 30% within 28 days. The chi-square test showed superiority of the interferon arm over the placebo arm with an error probability of alpha less than 1%. In addition, efficacy of interferon-gamma was demonstrated in respect of practically all parameters investigated. The frequency of side-effects, including febrile reactions, was the same for the active compound and the placebo. During interferon treatment the daily maximum body temperature was raised by 0.3 degrees C on average, but was below 37.2 degrees C at all times.

Isotope shift (IS) and hyperfine structure (HFS) measurements have been performed for185, 187, 189, 191, 195Pt using the PILIS (Post ISOCELE Laser Isobar Separator) apparatus installed at the ISOCELE facility. Magnetic and quadrupole moments have been deduced from the HFS results. The charge radius changes determined for these odd nuclei from the IS results, added to the σ values of the even-A nuclei are compared to the results of lattice Hartree-Fock+BCS calculations for asymmetric solutions:185Pt is confirmed to be prolate shaped whereas187, 189, 191Pt are likely triaxial in their ground states.

By on-line selective separation on molecular fluoride compounds at the ISOCELE 2 facility, two new isotopes:163Ta (T1/2=10.5+-1.8s) and162Ta (T1/2=3.5+-0.2s) have been identified.