Study of the reactione + e −→K + K − in the energy range1350 \leqq \sqrt s \leqq 2400 MeV

Thee ⁺ e ^?→K ⁺ K ^? cross section has been measured from about 750 events in the energy interval \(1350 \leqq \sqrt s \leqq 2400 MeV\) with the DM2 detector at DCI. TheK ^± form factor |F _F ^±| cannot be explained by the ρ, ω, ? and ρ′(1600). An additional resonant amplitude at 1650 MeV has to be added as suggested by a previous experiment.     

Experimental study of the time-dependent rate of K → πππ

The time-dependence of the decay rate of initially pure K⁰ into the final state (π⁺π⁻π⁰) has been studied in search for the decay k_S⁰→π⁺π⁻π⁰. No evidence is found in a sample of 384 observed events. The ratio of the CP -violating K_S⁰ amplitude and the K_L⁰ amplitude is η₊₋₀ = (0.13_−0.20^+0.17) + i(0.17_−0.26^+0.27); the ratio of the CP-conserving K_S⁰ amplitude and the K_L⁰ amplitude is < 0.4. The energy dependence of the K⁰→π⁺π⁻π⁰ matrix element is found to be a₊₋₀ = −0.31 ± 0.03.     

Radiative decay ofJ/ψ into γ π+ π−

The radiative decayJ/ψ → γ π⁺ π^? has been studied using the 8.6 millionJ/ψ produced in the DM2 experiment at the DCIe ⁺e^? storage rings at Orsay. The π⁺ π^? mass spectrum shows a cleanf ₂ (1270) signal, and the possible presence of two other states at thef ₂ (1720) andf ₄ (2030) masses. For thef ₂ (1270), the branching ratio BR(J/ψ →γf)xBR(f→π⁺ π^?) is measured to be (7.50±0.30±1.12)×10^?4, and the spin analysis prefers theJ=2 assignment, with helicity parametersx=0.83±0.06 andy=0.01±0.06. The existence of higher mass states is discussed.     

Nash equilibrium point for one kind of stochastic nonzero-sum game problem and BSDEs

In this Note, we deal with one kind of stochastic nonzero-sum differential game problem for N players. Using the theory of backward stochastic differential equations and Malliavin calculus, we give the explicit form of a Nash equilibrium point. To cite this article: J.-P. Lepeltier et al., C. R. Acad. Sci. Paris, Ser. I 347 (2009).     

Evidence for resonant structure near 1780 MeV in e+ e− annihilations observed with the new colliding beam ring at Orsay

We present evidence for the existence of a new J^PC = 1^?? resonance with a mass of 1778 ± 14 (±12) MeV and 150 ± 40 (±30) MeV wide. We tentatively conclude that it is an I = 0 state.     

Hadronic cross sections study in e+e− collisions from 1.350 GeV to 2.125 GeV

The results of the first experiment performed at DCI in e⁺e^? annihilations in the c.m. energy range 1.350–2.125 GeV region are presented. The cross sections of various multipion channels are extracted. Significant structure appears in some specific channels. A relatively narrow resonance around 1.660 GeV decaying into 3π's is found. Charged and neutral multiplicities, and also the ratio R are given.     

Multidisciplinary Preclinical Investigations on Three Oxamniquine Analogues as New Drug Candidates for Schistosomiasis**

Schistosomiasis is a disease of poverty affecting millions of people. Praziquantel (PZQ), with its strengths and weaknesses, is the only treatment available. We previously reported findings on three lead compounds derived from oxamniquine (OXA), an old antischistosomal drug: ferrocene-containing (Fc-CH₂-OXA), ruthenocene-containing (Rc-CH₂-OXA) and benzene-containing (Ph-CH₂-OXA) OXA derivatives. These derivatives showed excellent in vitro activity against both Schistosoma mansoni larvae and adult worms and S. haematobium adult worms, and were also active in vivo against adult S. mansoni. Encouraged by these promising results, we conducted additional in-depth preclinical studies and report in this investigation on metabolic stability studies, in vivo studies on S. haematobium and juvenile S. mansoni, computational simulations, and formulation development. Molecular dynamics simulations supported the in vitro results on the target protein. Though all three compounds were poorly stable within an acidic environment, they were only slightly cleared in the in vitro liver model. This is likely the reason why the promising in vitro activity did not translate into in vivo activity on S. haematobium. This limitation could not be overcome by the formulation of lipid nanocapsules as a way to improve the in vivo activity. Further studies should focus on increasing the compound's bioavailability, to reach an active concentration in the microenvironment of the parasite.     

New limits for the exotic exchange reaction π−p → K+Σ− at 5 and 8 GeV

Measurement of the exotic exchange reaction π^?p → K⁺Σ^? has been performed at 5 and 8 GeV, in the ?0.015 to ?0.13 and ?0.009 to ?0.15 (GeV/c)² range of t repectively. We give the value near t = 0 of the differential cross section at 5 GeV, 21_?21⁺⁷⁶ nb/(GeV/c)², and an upper limit (< 37 nb/GeV/c)²) at 8 GeV. As a check the measured differential cross section is given at both energies for the reaction π⁺p → K⁺Σ⁺ in the same range of t.