Bismuth (III) coordination to cyclen and cyclam bearing four appended groups

The synthesis of new cyclam and cyclen derivatives (respectively L₁ and L₂), able to efficiently coordinate to Bi(III) are presented here. The two ligands bearing two different pendant arms (two-pycolyl and two (2-(2-hydroxyethoxy)ethyl)-2-aminoacetamide in trans position) were synthesized in the aim to obtain stable and water soluble complexes. The thermodynamic and kinetic of the formation of the corresponding complexes in aqueous solution were studied by means of NMR and potentiometric investigations. The fast kinetic of complexation and the high stability of the complexes are encouraging for further application with the alpha-emitting ²¹³Bi isotope.     

Activation and structural and adsorption features of activated carbons with highly developed micro-, meso- and macroporosity

Three sets of activated carbons (ACs) were prepared with the same precursor but activated differently (by CO₂ or water vapour) with various burn-off levels. The ACs demonstrate increased deviation of the pore shape from the slitshaped model with increasing burn-off and contributions of pores of different sizes depending on the activation type. Significant re-arrangement of adsorption complexes, especially of the Van der Waals type characteristic for nonpolar or weakly polar adsorbates (H₂, CH₄, CH₂Cl₂, CHCl₃), occurs in both micropores and mesopores of ACs with decreasing temperature. The behaviour of their mixtures with water and DMSO can strongly differ from that of individual adsorbates.     

Concentration-Dependent Interactions of Amphiphilic PiB Derivative Metal Complexes with Amyloid Peptides Aβ and Amylin**

Metal chelates targeted to amyloid peptides are widely explored as diagnostic tools or therapeutic agents. The attachment of a metal complex to amyloid recognition units typically leads to a decrease in peptide affinity. We show here that by separating a macrocyclic GdL chelate and a PiB targeting unit with a long hydrophobic C10 linker, it is possible to attain nanomolar affinities for both Aβ_1-40 (K_d=4.4 nm ) and amylin (K_d=4.5 nm ), implicated, respectively in Alzheimer's disease and diabetes. The Scatchard analysis of surface plasmon resonance data obtained for a series of amphiphilic, PiB derivative GdL complexes indicate that their Aβ_1-40 or amylin binding affinity varies with their concentration, thus micellar aggregation state. The GdL chelates also affect peptide aggregation kinetics, as probed by thioflavin-T fluorescence assays. A 2D NMR study allowed identifying that the hydrophilic region of Aβ_1-40 is involved in the interaction between the monomer peptide and the Gd³⁺ complex. Finally, ex vivo biodistribution experiments were conducted in healthy mice by using ¹¹¹In labeled analogues. Their pancreatic uptake, ∼3 %ID g⁻¹, is promising to envisage amylin imaging in diabetic animals.     

High energy electronic neutrino (ve) and antineutrino (ve) interactions

The total cross-sections for $\text{v}{}_{\mathrm{<mtext>e</mtext>}}\text{(}\text{v}{}_{\mathrm{<mtext>e</mtext>}}\text{)}$-nucleon scattering have been measured. A test has been made of the muon number conservation law. A limit of 2.4 GeV is found the mass of the “Georgi-Glashow type” heavy lepton     

Dilepton and strange particles production by neutrinos in gargamelle

New results are presented of an analysis of pictures taken during an exposure of Gargamelle to the CERN ν beam in 1975. In addition to three ν_μ+N→μ^?+e⁺+V⁰+ hadrons events previously reported, an excess is found of events of the type ν_μ+N→μ^?+e⁺+ hadrons without V⁰. An analysis of strange particle production in charged current events suggests a possible violation of the ΔS=ΔQ rule. Interpreted in terms of charm production, the data permit an estimate of branching ratios and production rate of charmed particles. A limit is also placed on charmed particle production by neutral currents.