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The spectrum of 9He was studied by means of the 8He(d,p)9He reaction at a lab energy of 25 MeV/n and small center of mass (c.m.) angles. Energy and angular correlations were obtained for the 9He decay products by complete kinematical reconstruction. The data analysis was done in the assumption of a direct one-neutron transfer reaction mechanism. The 9He structure was analysed in the framework of a simple single-particle model. The lowest resonant state of 9He is found at about 2 MeV with a width of ∼2MeV and is identified as 1/2-. The observed angular correlation pattern is uniquely explained by the interference of the 1/2-resonance with a virtual state 1/2+(a limit on the scattering length is obtained as a > -20fm), and with a 5/2+resonance at energy ≥4.2MeV.

Abstract.: The spectrum of 9He was studied by means of the 8He(d,p)9He reaction at a lab energy of 25 MeV/n and small center of mass (c.m.) angles. Energy and angular correlations were obtained for the 9He decay products by complete kinematical reconstruction. The data analysis was done in the assumption of a direct one-neutron transfer reaction mechanism. The 9He structure was analysed in the framework of a simple single-particle model. The lowest resonant state of 9He is found at about 2 MeV with a width of ∼2MeV and is identified as 1/2-. The observed angular correlation pattern is uniquely explained by the interference of the 1/2- resonance with a virtual state 1/2+ (a limit on the scattering length is obtained as a > -20fm), and with a 5/2+ resonance at energy ≥4.2MeV.

The spectrum of 9He was studied by means of the 8He(d,p)9He reaction at a lab energy of 25?MeV/n and small center of mass (c.m.) angles. Energy and angular correlations were obtained for the 9He decay products by complete kinematical reconstruction. The data analysis was done in the assumption of a direct one-neutron transfer reaction mechanism. The 9He structure was analysed in the framework of a simple single-particle model. The lowest resonant state of 9He is found at about 2?MeV with a width of ?2MeV and is identified as 1/2-. The observed angular correlation pattern is uniquely explained by the interference of the 1/2-resonance with a virtual state 1/2+(a limit on the scattering length is obtained as a > -20fm), and with a 5/2+resonance at energy ?4.2MeV.

The structure of the neutron-rich nucleus 45Ar has been investigated through the d(44Ar,45Ar)p transfer reaction. Radioactive beam of 44Ar at 10 A MeV has been provided by the SPIRAL facility at GANIL. The protons corresponding to a neutron pick-up on bound or unbound states mechanism in 45Ar nuclei were detected at backward angles by the detector array MUST. The transfer-like ejectiles were detected in the SPEG spectrometer. Level scheme, spin assignments and spectroscopic factors have been deduced for 45Ar and compared to shell model predictions. These parameters will be subsequently used to infer (n, γ) cross sections in the Ar isotopic chain for astrophysical purposes.

Cardiopulmonary bypass triggers a systemic inflammatory response that alters pulmonary endothelial function, which can contribute to pulmonary hypertension. This study was designed to demonstrate that inhaled prostacyclin, a selective pulmonary vasodilator prostaglandin, prevents pulmonary arterial endothelial dysfunction induced by cardiopulmonary bypass.

The 11B(7Li,7Be)11Be reaction at 57 MeV incident energy was studied at forward angles in order to explore the 11Be excitation energy spectrum. The 11Be ground state and the states at E∗=0.32,1.77,2.67,3.41,3.89,3.96,6.05 MeV excitation energies were populated. The state at 6.05 MeV (FWHM 320±40 keV) has not been previously observed. The good energy resolution (∼50 keV) allowed the identification of these transitions each for 7Be in its ground and first excited state at E∗=0.429 MeV. QRPA calculations reproduce the 11Be level structure below 2 MeV of excitation energy. The strength observed at higher excitation energies is very likely produced mainly by core-excited components of 11Be.

The 11Be(p,d)10Be reaction has been performed in inverse kinematics with a radioactive 11Be beam of E/A=35.3MeV. Angular distributions for the 0+ground state, the 2+, 3.37 MeV state and the multiplet of states around 6 MeV in 10Be were measured at angles up to 16°cmby detecting the 10Be in a dispersion-matched spectrometer and the coincident deuterons in a silicon array. Distorted wave and coupled-channels calculations have been performed to investigate the amount of 2+core excitation in 11Begs. The use of “realistic” 11Be wave functions is emphasised and bound-state form factors have been obtained by solving the particle-vibration coupling equations. This calculation gives a dominant 2scomponent in the 11Begswave function with a 16% [2+⊗1d] core excitation admixture. Cross sections calculated with these form factors are in good agreement with the present data. The Separation Energy prescription for the bound-state wave function also gives satisfactory fits to the data, but leads to a significantly larger [2+⊗1d] component in 11Begs.

Rat liver parenchyma Golgi/endosomes fractions harbor a tyrosine-phosphorylated 34-kDa protein. Screening of Golgi, endosomes (ENs), plasmalemma (PM), and cytosolic (Cyt) fractions revealed the presence of the mitotic kinase Cdk2 in ENs, PM, and Cyt. The fluid phase endocytic marker horseradish peroxidase gained access to the endosomal Cdk2, confirming its localization. Cdk2 was shown to be associated to cyclin E and was active in ENs and PM fractions. The administration of a single dose of insulin (1.5 microgram/100 g, body weight) induced a time-dependent activation of the insulin receptor kinase in these structures. Insulin receptor-kinase activation was followed by the inhibition of immunoprecipitated Cdk2-cyclin E kinase activity in PM and the progressive disappearance of cyclin E. In marked contrast, no such effect was observed in ENs. The injection of a phosphotyrosyl phosphatase inhibitor (bpV(phen)) increased the levels of cyclin E in ENs and PM. A massive recruitment of p27(kip1) was observed in the Cdk2-cyclin E complexes isolated from PM and Cyt but not from ENs. In vitro, Cdk2-cyclin E complexes have the capacity to inhibit the formation of hybrid structures containing horseradish peroxidase and radioiodinated epidermal growth factor. Therefore, in the PM and ENs of adult rat liver, an active and regulated pool of the mitotic kinase Cdk2-cyclin E and some yet to be defined effectors are present. Cdk2 may contribute to the modulation of transport events and/or maintenance of the topology of endocytic elements.

Rb-Sr isotopic dating of phlogopite megacryst samples separated from Sturgeon Lake kimberlite, Saskatchewan, yields a crystallization age of 98±1 Ma (2 s, MSWD=1.2; 87Sr/86Sr(t)=0.7059). The 40Ar/39Ar analyses of a phlogopite megacryst sample indicate the presence of large amounts of excess 40Ar and yield an excessively old age of ~410 Ma. Assessment of the Ar data using isotope correlation plots indicates clustering of the data points about a mixing line between the radiogenic 40Ar component at 98 Ma and a trapped component with uniform 36Ar/40Ar and Cl/40Ar. Values of {ie212-1} as high as +20%. (VSMOW) for calcite from the groundmass and a whole-rock sample indicate pervasive lowtemperature alteration. The {ie212-2} of matrix carbonate is-11.3%. (PDB), slightly lighter than typical values from the literature. The {ie212-3} values of about +5%. (VSMOW) for brown phlogopite megacrysts may be primary, green phlogopites are interpreted to be an alteration product of the brown variety and are 2%. heavier. Initial Nd-Sr-Pb isotopic ratios for a whole-rock sample {ie212-4}; 87Sr/86Sr=0.7063, 206Pb/204Pb=18.67, 207Pb/204Pb=15.54, 208Pb/204Pb=38.97) suggest an affinity with group I kimberlites. Initial {ie212-5} values of +1.7 and +0.5 (87Sr/ 86Sr(t)=0.7053 and 0.7050) for eclogitic and lherzolitic garnet megacryst samples, and values of 0.0 for two phlogopite megacryst samples reflect an origin from an isotopically evolving melt due to assimilation of heterogeneous mantle. Lilac high-Cr lherzolitic garnet megacrysts give an unusually high {ie212-6} of +28.6 (87Sr/86Sr=0.7046) indicating a xenocrystic origin probably from the lithospheric mantle. The very radiogenic 87Sr/86Sr and 206Pb/204Pb ratios of the kimberlite are consistent with melting of EM II (enriched) mantle components.

(±)-Deoxybutaclamol, C25H31N, crystallizes in space group P21/awith cell dimensions: a = 16.626(3), b = 10.646(2), c = 11.278(3) Å, β = 90.47(4)°. The structure was solved by direct methods using the QTAN program. The coordinates were refined by block-diagonal least-squares calculations to R = 0.052 for 3147 observed reflections.The structure of (±)-deoxybutaclamol was found to be very similar to that of equipotent (±)-butaclamol and is in agreement with that assigned on the basis of chemical, spectral, crystallographic, and pharmacological studies. This confirmation validates the coordinates of a lipophilic accessory binding site in a proposed model of the central dopamine receptor.

Solid phase 45.3 MHz 13C NMR spectra of ortho-dimethoxydiphenyl ether, 1, dibenzo[b,e]-15-crown-5- ether, 2, and tetrabenzo[b,e,q,t]-30-crown-10 ether, 3, have been obtained. Chemical shift trends are discussed in terms of the asymmetric units and structural features available from X-ray crystallographic data. Comparison with solution 13C spectra are made. The crystal structures of 1and 3were determined by X-ray diffraction at room temperature. 1crystallizes in space group P21/awith a = 13.366(1), b = 8.230(1), c = 12.303(1) Å, β = 116.63(1)°, Z = 4. 3crystallizes in space group P21/cwith a = 7.903(1), b = 26.337(2), c = 7.852(1) Å, β = 97.28(1)°, Z = 2. The structures were solved by direct methods and refined by full-matrix least squares to residuals of 0.055 using 1727 reflections for 1and of 0.042 using 2590 reflections for 3.

A search for proton radioactivity in65As,69Br and77Y, produced as residues of fusion reactions, was carried out at the Orsay Tandem accelerator. The residues were collected at the image point of the spectrometer Soleno and implanted into the gaseous medium of an ionization chamber which was also used to detect the radioactivity protons. No such protons have been observed in the energy range of 250–600 keV and in the half-life interval of 10 µs-100 ms, within a production cross section sensitivity of 1 µb.

The48, 50Ti(τ, d) reactions, investigated at 25 MeV incident energy with a split pole spectrometer, were used to populate highly excited analog states in51V and some levels in49V. Angular distributions were measured for the p3/2,p1/2,f5/2and g9/2, analog states of 51Ti levels and for some strong analog transitions in 49V. A DWBA analysis of the data for these unbound levels (using Gamov functions as form factors) was carried out and spectroscopic strengths extracted. The 48,50Ti(τ, dp˜) reaction was performed at 25.5 MeV incident energy. The angular distributions of the emitted protons were measured in coincidence using method II of Litherland and Ferguson with 0° detection of deuteron groups. Spins, population parameters and branching ratios of proton partial widths to the ground and excited states of the target were determined from the analysis of the angular correlation data. The combined results of these two experiments provide a complete set of spectroscopic data concerning the analog states in 49V and 51V. A comparison is made with the previous (p, γ), (p, p), (p, p') and (d, p) results on the same targets. The amplitudes of neutron coupling to excited states of 48Ti and 50Ti nuclei are also determined for the f5/2and g9/2isobaric analog states in 51V and p3/2and d5/2analog levels of 49Ti states.

J Thorac Cardiovasc Surg 2003;125:204-5

The hairpin conformational hypothesis1has been proposed to rationalise much of the structure–activity and receptor-binding data which have accumulated for the prostaglandin (PG) hormones. The hairpin conformation, thought to be necessary for PG activity, requires that the α- and ω-chains of the molecule be extended and in parallel alignment, separated by a van der Waals contact distance for the full length of the chains, with the ends of the chains approximately 5.5 Å apart. The similarity between the structures of the thromboxanes (TXs) and the PGs suggests that the profile of activity of TXs, like that of PGs, centres on subtle conformational variation of the hairpin geometry. Thromboxane B2(TXB2) is a stable hydrolysis product2of a highly reactive, short-lived intermediate3, thromboxane A2(TXA2), which is formed from the prostaglandin endoperoxide (PGH2) as indicated in Fig. 1. An examination of molecular models of TXA2and TXB2suggests that the struc tural differences between the ring moieties may have much less influence in altering the side-chain conformations of TXs than do substituents on the relatively more flexible cyclopentane ring of a PG molecule. We report here the first diffraction analysis of a thromboxane structure and note that the molecular conformation is not hairpin shaped.