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.     

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.     

Divergent synthetic approach to 6'-modified α-GalCer analogues

A synthetic approach is presented for the synthesis of galacturonic acid and D-fucosyl modified KRN7000. The approach allows for late-stage functionalisation of both the sugar 6'-OH and the sphingosine amino groups, which enables convenient synthesis of promising 6'-modified KRN7000 analogues.     

Non-planar smoulder propagation governed by diffusion

The steady propagation of a thin smouldering front in a half-spacehas been considered. A suitable coordinate transformation hasallowed the region near the leading edge of the front to beexamined for both a maintained planar surface and with surfacecollapse due to material shrinkage. The change in the oxidizerconcentration for a small increment in the propagation speedfor large time and surface collapse has been determined. Theinfluence of two types of nonlinear diffusion on the shape ofthe smouldering front has been found; other cases can be dealtwith in a similar manner.     

Proposed quantum-beats,quantum-eraser experiment

An experiment is proposed which demonstrates that quantum-interference effects are contingent on the presence or absence of residual information in the atom or scattered radiation field. The experiment may also be operated in a delayed-choice mode.     

Ternäre Halogenide vom Typ A3MX6. VI [1]. Ternäre Chloride der Selten-Erd-Elemente mit Lithium,Li3MCl6 (M  Tb?Lu,Y, Sc): Synthese,Kristallstrukturen und Ionenbewegung

Ternary Halides of the A₃MX₆ Type. VI. Ternary Chlorides of the Rare-Earth Elements with Lithium, Li₃MCl₆ (M ? Tb? Lu, Y, Sc): Synthesis, Crystal Structures, and Ionic Motion Single crystal X-ray studies on the ternary chlorides Li₃ErCl₆, Li₃YbCl₆ and Li₃ScCl₆ show that they crystallize in three different structure types. Li₃ErCl₆ (trigonal, P3 ml, Z = 3, a = 1117.7(2); c = 603.6(2) pm; the chlorides with M ? Tb? Tm, Y are isotypic) and Li₃YbCl₆ (orthorhombic, Pnma, Z = 4, a = 1286.6(1); b = 1113.2(1); c = 602.95(8) pm; Li₃LuCl₆ is isotypic) have very similar structures that may be derived from hexagonal closest packings of chloride ions with the cations occupying octahedral holes in part statistically. Li₃ScCl₆ (monoclinic, C2/m, Z = 2, a = 639.8(1); b = 1104.0(2); c = 639,1(1) pm; β = 109.89(1)°) crystallizes isotypic with Na₃GdI₆ and Li₃ErBr₆, structures that may be derived from a cubic closes packings of anions. The ionic movement in Li₃YCl₆ and Li₃YbCl₆ has been investigated by impedance and ⁷Li-NMR spectroscopy.     

Glycolipids that elicit IFN-γ-biased responses from natural killer T cells

Natural killer T (NKT) cells recognize glycolipids presented by CD1d. The first antigen described, α-galactosyl ceramide (αGalCer), is a potential anticancer agent whose activity depends upon IFN-γ secretion. We report two analogs of αGalCer based on a naturally occurring glycosphingolipid, plakoside A. These compounds induce enhanced IFN-γ that correlates with detergent-resistant binding to CD1d and an increased stability of the lipid-CD1d complexes on antigen-presenting cells. Structural analysis on one of the analogs indicates that it is more deeply bound inside the CD1d groove, suggesting tighter lipid-CD1d interactions. To our knowledge, this is the first example in which structural information provides an explanation for the increased lipid-CD1d stability, likely responsible for the Th1 bias. We provide insights into the mechanism of IFN-γ-inducing compounds, and because our compounds activate human NKT cells, they could have therapeutic utility.     

KMgF3:Ni2+晶体的占位、局部结构、吸收光谱和顺磁g因子的统一解释

利用完全对角化方法和强场耦合方案,采用半自洽场(semi-SCF)自由Ni2+的d轨道模型和Ni2+-6X-(x=F,Cl,Br,I)络合物的μ-κ-α模型研究,建立了含有过渡族金属离子的晶体的局域结构与吸收光谱和顺磁g因子之间的定量关系,对KMgF3:Ni2+晶体的占位、局域结构、吸收光谱和顺磁g因子作出了统一解释,预测了KMgF3:Ni2+晶体的光谱精细结构.所得理论计算结果与实验值符合得很好.     

Baryon pairs production ine + e − annihilation at\sqrt s = 2.4 GeV

Search for baryon pairs production ine ⁺ e ^? annihilation at \(\sqrt s = 2386 MeV\) is reported. The data relate to a luminosity of 161 nb^?1 collected by the DM2 experiment at DCI, the Orsay colliding ring. First measurements of directe ⁺ e ^? annihilation into \(\Lambda \bar \Lambda \) and ofe ⁺ e ^?→ \(p\bar p\) at this energy are presented. First observation of a goode ⁺ e ^?→ \(n\bar n\) candidate is reported and upper limits are given fore ⁺ e ^?→ \(n\bar n, \Lambda \bar \sum ^0 + c.c.\) and \(\Sigma ^0 \bar \Sigma ^0 \) .