An analysis of the Λ (1520) observed in a K− neutron production experiment

The mass, width and branching fractions of the Λ(1520) into $\text{K}\text{N, σπ, Λππ}\text{and}\text{σππ}$ have been determined using a Λ(1520) sample produced in the reaction K^?d→Λ(1520)π^?p_s at K^? -neutron centre-of-mass energies between 1.9 and 2.2 GeV. A Dalitz plot analysis of the Λ⁰π⁺π^? decay mode shows that there is a substantial Σ(1385)π component. The SU(3) octet-singlet mixing angle for the $\text{3}\text{2}{}^{\mathrm{?}}$ baryons calculated from the partial widths for the s-wave σ(1385)π decay of the Λ(1520) and Λ(1690) is found to be consistent with that obtained from the d-wave decays of the singlet and octet members, within experimental limits.     

Measurements of the reaction K−n → π−Λ in the C.M.S. energy range 2050 MeV to 2175 MeV and partial-wave analysis of this reaction between 1875 MeV and 2175 MeV

New bubble chamber data on the reaction K^?n → π^?Λ in the c.m.s. energy range 2050 MeV to 2175 MeV are presented. These new data have been combined with published data on this reaction and on the reaction K^?p → π⁰Λ and a partial-wave analysis has been carried out between 1875 MeV and 2175 MeV. Parameters of the established resonances in this c.m.s. energy region have been determined and further evidence is presented for the existence of a Σ resonance with mass around 2100 MeV/c² in the P₃ partial wave.     

Test of the Zweig rule in π−p interactions at 19 GeV/c

We have observed φ production in π^?p interactions at 19 GeV/c with (44±10) events in the final state φπ⁺π^?π^?p and (45±9) events in φK⁺K^?π^?p. The production ratios φπ⁺π^?π^?p/ωπ⁺π^?π^?p ≈ 0.005 and φK⁺K^?π^?p/?°K⁺K^?π^?p ≈ 0.45 agree with Zweig-rule expectations.     

ω Production in the reaction π−p → π+π−π0n at 8 and 12 GeV/c

The reaction π^?p → ωn has been studied at 8 and 12 GeV/c incident momenta with the CERN Omega spectrometer using a neutron time of flight trigger. The differential cross sections and the ω-decay density matrix elements are presented as functions of the momentum transfer squared ?t in the range of 0.02 to 0.80 GeV². The data are used to evaluate the intercept and slope of both the natural and unnatural parity exchange trajectories. Regge exchange amplitude factorisation tests involving the reaction πN → ωN are investigated.     

Redox inactivation of human 15-lipoxygenase by marine-derived meroditerpenes and synthetic chromanes: archetypes for a unique class of selective and recyclable inhibitors

The selective inhibition of human 15-lipoxygenase (15-hLO) could serve as a promising therapeutic target for the prevention of atherosclerosis. A screening of marine sponges revealed that crude extracts of Psammocinia sp. exhibited potent 15-hLO inhibitory activity. Bioassay-guided fractionation led to the isolation of chromarols A-E (8-12) as potent and selective inhibitors of 15-hLO. An additional 22 structurally related compounds, including meroditerpenes from the same Psammocinia sp. (3, 4, 13-16) and our pure compound repository (17, 18), commercially available tocopherols (19-24), and synthetic chromanes (25-32), were evaluated for their ability to inhibit human lipoxygenases. The 6-hydroxychromane moiety found in chromarols A-D was identified as essential for the selective redox inhibition of 15-hLO. Furthermore, the oxidized form of the 6-hydroxychromane could be reduced by ascorbate, suggesting a potential regeneration pathway for these inhibitors in the body. This pharmacophore represents a promising paradigm for the development of a unique class of recyclable 15-hLO redox inhibitors for the treatment of atherosclerosis.     

Nonzero Infinitesimal Blocks of Category $\boldsymbol{\mathcal{O}}_{\textbf{\emph{S}}}$

Category \(\mathcal{O}\) is a nice category of modules for a finite dimensional semisimple Lie algebra \(\mathfrak{g}\) It was first introduced by Bernstein–Gelfand–Gelfand in 1976. In the early 1980’s, Rocha–Caridi introduced parabolic category \(\mathcal{O}_S\), where S is a subset of simple roots. Category \(\mathcal{O}_S\) is a generalization of ordinary category O. These are highest weight categories that decompose into certain subcategories, called infinitesimal blocks. An infinitesimal block contains at most finitely many simple modules, and some contain only the zero module. The representation type of the infinitesimal blocks of category \(\mathcal{O}_S\) has been studied by Futorny–Nakano–Pollack, Brüstle–König–Mazorchuk, and Boe–Nakano. The representation type of the singular blocks of category \(\mathcal{O}_S\) is still generally unknown, though Boe–Nakano classified certain of these. Understanding when a singular block is zero is an important step to understanding the singular blocks in general. In this work, we will answer this question. It is given in terms of nilpotent orbits of \(\mathfrak{g}\).     

Studies Towards the Synthesis of ATP Analogs as Potential Glutamine Synthetase Inhibitors

In research directed at the development of adenine triphosphate (ATP) analogs as potential glutamine synthetase (GS) inhibitors, adenine and allopurinol derivatives have been synthesized either as novel ATP analogs or as scaffolds for the construction of such analogs.