Detection of Ser/Thr protein phosphatases in Neurospora crassa

Protein phosphorylation is a frequent posttranslational modification regulating cellular processes in eukaryotes. The phosphate content of a protein is determined by the conflicting activities of protein kinases and phosphatases. Protein phosphatases were divided into Ser/Thr and Tyr specific groups, depending on the phosphorylated residue in the substrate molecules. The former group was further classified based on enzymatic criteria (reviewed in Cohen 1989 Ann. Rev. Biochem. 58:453-508). Protein phosphatase 1 (PP1) is inhibited by two heat stable proteins termed inhibitor-1 and -2. Protein phosphatase 2A is inhibited by nanomolar concentration of the tumor promoter okadaic acid. Protein phosphatase 2B (PP2B) - also called calcineurin - is stimulated by Ca-calmodulin, and protein phosphatase 2C (PP2C) is a Mg2+ dependent enzyme. Molecular cloning of the catalytic subunits revealed that PP1-PP2A-PP2B consist of a highly conserved superfamily of proteins

Collectivity evolution in the neutron-rich Pd isotopes towards the N=82 shell closure

The neutron-rich, even-even 122,124,126Pd isotopes has been studied via in-beam gamma-ray spectroscopy at the RIKEN Radioactive Isotope Beam Factory. Excited states at 499(9), 590(11), and 686(17) keV were found in the three isotopes, which we assign to the respective 2+ -> 0+ decays. In addition, a candidate for the 4+ state at 1164(20) keV was observed in 122Pd. The resulting Ex(2+) systematics are essentially similar to those of the Xe (Z=54) isotopic chain and theoretical prediction by IBM-2, suggesting no serious shell quenching in the Pd isotopes in the vicinity of N=82

Prolate-Spherical Shape Coexistence at N=28 in 44^{44}S

The structure of $^{44}$S has been studied using delayed $\gamma$ and electron spectroscopy at \textsc{ganil}. The decay rates of the 0$^+_2$ isomeric state to the 2$^+_1$ and 0$^+_1$ states have been measured for the first time, leading to a reduced transition probability B(E2~:~2$^{+}_1$$\rightarrow$0$^{+}_2)$= 8.4(26)~e$^2$fm$^4$ and a monopole strength $\rho^2$(E0~:~0$^{+}_2$$\rightarrow$0$^{+}_1)$ =~8.7(7)$\times$10$^{-3}$. Comparisons to shell model calculations point towards prolate-spherical shape coexistence and a phenomenological two level mixing model is used to extract a weak mixing between the two configurations.Comment: 5 pages, 3 figures, accepted for publication in Physical Review Letter

γ-ray spectroscopy of C19 via the single-neutron knock-out reaction

The one-neutron knock-out reaction H-1(C-20, C-19 gamma) was studied at RIKEN using the DALI2 array. A gamma-ray transition was observed at 198(10) keV. Based on the comparison between the experimental production cross section and theoretical predictions, the transition was assigned to the de-excitation of the 3/2(1)(+) state to the ground state

Excited states in neutron rich boron isotopes

Publisher's version/PDFNew experimental results on in-beam gamma spectroscopy of neutron rich boron isotopes are presented for [superscript 17]B and its neutron removal fragments [superscript 14,15]B, after scattering with a H[subscript 2] target. A gamma transition for [superscript 17]B is observed at 1089 [plus or minus] 15 keV. The fragment [superscript 15]B is observed abundantly associated with a gamma transition of 1336 [plus or minus] 10 keV. This suggests for the first time a core-excited structure for [superscript 17]B thereby providing a new insight into its structure. Observations for [superscript 12,14]B are also presented. The data set provides a useful systematic study of first excited states of neutron rich boron isotopes showing the dramatic drop in excitation energy beyond N = 8

Structure of ^112In nucleus

The γ-ray spectra of the ^112Cd(p,nγ)^112In and ^109Ag(α,nγ)^112In reactions were measured with Ge(Li) spectrometers for bombarding energies of 4.8 MeV protons and 17.1 MeV α particles. The energies and relative intensities of 79 ^112In γ-ray transitions have been determined. The electron spectra were measured with combined magnet plus Si(Li) as well as superconducting magnetic lens plus Si(Li) spectrometers. Internal conversion coefficients of 40 ^112In transitions have been determined, and the level scheme of ^112In, γ-ray branching ratios and transition multipolarities have been deduced. Computed Hauser-Feshbach (p,n) cross sections were compared with experimental ones, obtained from γ-ray measurements. On the basis of the internal conversion coefficients and Hauser-Feshbach analysis, level spins and parities have been determined. The energies of several ^112In proton-neutron multiplets were calculated on the basis of the parabolic rule derived from the cluster-vibration model. The level energy spectrum and electromagnetic properties were calculated on the basis of the interacting boson-fermion-fermion/odd-odd truncated quadrupole phonon model and satisfactory agreement was obtained between the experimental and theoretical results. More than 20 p-n multiplet states have been identified in ^112In

Decay of a Jπ=36+J^{\pi}=36^+ Resonance in the 24Mg+24Mg^{24}Mg + ^{24}Mg Reaction

The narrow ($\Gamma$=170 keV) and high spin ($J^{\pi}=36^+$) resonance in the $^{24}$Mg + $^{24}$Mg reaction at E$_{CM}$= 45.7 MeV has been associated with a hyperdeformed molecular state in $^{48}$Cr. Such a description has important consequences for the resonance decay into the favored inelastic channels. Through fragment- $\gamma$ coincidence measurements performed ON and OFF resonance using the PRISMA-CLARA array, we have identified the $^{24}$Mg states selectively populated: the $2^+$ and $4^+$ members of the ground state band

Structure of the N=27 isotones derived from the 44^{44}Ar(d,p)45^{45}Ar

Expérience GANIL/SPIRAL, détecteur CATS, détecteur MUST, 7 figures,International audienceThe $^{44}$Ar(d,p)$^{45}$Ar neutron transfer reaction was performed at 10~A.MeV. Measured excitation energies, deduced angular momenta and spectroscopic factors of the states populated in $^{45}$Ar are reported. A satisfactory description of these properties is achieved in the shell model framework using a new $sdpf$ interaction. The model analysis is extended to more exotic even-Z nuclei down to $^{41}_{14}$Si$_{27}$ to study how collectivity impacts the low lying structure of N~=~27 neutron-rich nuclei

Isomer Spectroscopy of Neutron-rich 165,167Tb

Open Access JournalWe present information on the excited states in the prolate-deformed, neutron-rich nuclei 165;167Tb100;102. The nuclei of interest were synthesized following in-flight fission of a 345 MeV per nucleon 238U primary beam on a 2 mm 9Be target at the Radioactive Ion-Beam Factory (RIBF), RIKEN, Japan. The exotic nuclei were separated and identified event-by-event using the BigRIPS separator, with discrete energy gamma-ray decays from isomeric states with half-lives in the _s regime measured using the EURICA gamma-ray spectrometer. Metastable-state decays are identified in 165Tb and 167Tb and interpreted as arising from hindered E1 decay from the 7/2-[523] single quasi-proton Nilsson configuration to rotational states built on the 3/2-[411] single quasi-proton ground state. These data correspond to the first spectroscopic information in the heaviest, odd-A terbium isotopes reported to date and provide information on proton Nilsson configurations which reside close to the Fermi surface as the 170Dy doubly-midshell nucleus is approached.postprin

Nature and decay of a JπJ\pi=36+36^{+} resonance in the 24^{24}Mg + 24^{24}Mg reaction

It has been proposed to associate the narrow (\Gamma=170 keV) and high spin ($J\pi$=36^+) resonance in the 24Mg + 24Mg reaction at E_c.m= 45.7 MeV with a hyperdeformed molecular state in 48Cr. Such a description has important consequences for the resonance decay into the favoured inelastic channels. Through fragment- coincidence measurements performed ON and OFF resonance using the PRISMA-CLARA array, we have established that the 24Mg states selectively populated are the 2^+ and 4^+ members of the ground state band