Inclusive Pomeron-Pomeron interactions at the CERN ISR

Data are presented for the first time on inclusive Pomeron-Pomeron interactions which produce a central systemX (composed mainly of multimeson states) in proton-proton collisions at \(\sqrt s \) at the CERN ISR. The systemX has a Feynman-x distribution which is sharply peaked atx _f=0, is inconsistent with any significant contributions from Reggeon exchange processes, and has an invariant mass dependence in good agreement with the predicted formM _x ^?2 . Kaon production is about 15% of pion production, nearly independent ofM _x, while proton-antiproton production averages about 5% of pion production and increases withM _x. The structure of the central systemX develops into a jetlike shape, asM _x increases, as would be expected from a model of Pomeron fragmentation. The shape of thex _f(π) distribution in the center of mass of theX system (although not proving existence) is consistent with asoft partonic substructure of the Pomeron.     

A New Cycloartane Triterpene Glycoside from Souliea vaginata

Souliea vaginata (Maxim.) Franch. (Ranunculaceae) is widely distributed in the southwest and northwest of China. It possesses anti-inflammatory analgesic functions as a well-known Chinese folk medicine. Its rhizomes or the whole plant are used to treat conjunctivitis, stomatitis, pharyngitis, enteritis, and diarrhea1. Previously, we have reported the isolation and structural elucidation of suolieasides A-C from the ethanol extract of the rhizomes of this plant2. In our further investigation…     

Neutral transverse momentum spectra in 60 and 200A·GeV16O+nucleus and proton+nucleus reactions

Transverse momentum (p _T) distributions fo inclusive photons and neutral pions at midrapidity are measured with a lead glass calorimeter in 60 and are measured with a lead glass calorimeter in 60 and 200A·Gev¹⁶O+nucleus and and proton+nucleus reactions. Inclusive photon distributions are compared for central and peripheral reactions. The degree of centrality is determined either from the charged particle multiplicity or from the remaining projectile energy in the forward direction. Deviations from a nucleus+nucleus interaction model based upon linear extrapolation from p+p reactions are observed in central¹⁶O+Au data. The variation of theaverage transverse momentum is investigated as function of centrality. The target-mass and energy dependence of π⁰ p _T distributions are presented. For¹⁶O+Au a change of slope in these distributions is observed atp _t ≈0.8 GeV/c compatible with hydrodynamic expansion models.     

Search for supermassive magnetic monopoles with the MACRO detector at the gran sasso laboratory

We present the results of the search for supermassive magnetic monopoles with the MACRO experiment. Our detector is equipped with three independent subdetectors (liquid scintillation counters, limited streamer tubes and nuclear track detectors), operating in different ranges of monopole velocity. In several years of data taking no candidates were found; the present flux upper limits are the level of half the Parker Bound for β > 10⁻⁴; for 10⁻⁴ < β < 5 × 10⁻² the limit is the best existing.     

InclusiveK *'s and∑ *'s production in 360 GeV/cpp interactions using the European hybrid spectrometer

We have studied the inclusive production of strange meson and baryon resonances in 360 GeV/cpp interactions. Cross sections forK ^*+(892) andK ^*?(892) are estimated to be 4.42±0.62 mb and 2.54±0.47 mb respectively and those for∑ ⁺(1385) and∑ ^?(1385) are 0.67±0.11 mb and 0.26±0.07 mb respectively. Longitudinal and transverse momentum distributions forK ^*(892) and Σ(1385) are presented, as well as for their decay productsK ⁰ and Λ. An estimation is given on theK ^*(1430) and∑ ^*(1915) productions.     

H^＋5团簇离子的形成和分解

简报报告了１．８ＭｅＶ的Ｈ＋５团簇离子及其产物的测量结果。讨论了Ｈ＋５的形成和分解反应。     

Design and Solid-Phase Synthesis of Multiple Muramyl Dipeptide (MMD)

As a non-specific modulator of macrophage, muramyl dipeptide elicits potentially multiple biological activities1, such as adjuvancy, antitumor, antiinfection, etc. Particularly, its adjuvancy has been studied by application for HIV vaccine. However, muramyl dipeptide can not serve as clinical agent due to its short lifetime in vivo, low immunogenicity, toxicity, and side effect such as pyrogenicity. Therefore, multiplied muramyl dipeptide (MMD) might increase its immunogenicity, decrease i…     

Resveratrol Tetramers from the Roots of Ampelopsis sinica

Various biological activities of stilbenoids have been described, such as antifungal and antibacterial activities1, antihepatotoxic activity2-4, anti-HIV activity5. Stilbenoids mainly existed in Vitaceae, Diperocarpaceae, Gnetaceae, Cyperaceae, Leguminase1. Many oligostilbenes have been isolated from Vitaceaeous plants. But, there was no report on the stilbenoids in Ampelopsis sinica (Miq.) W. T. Wang which was traditionari- ly used to treat arthritis6. In our study on the constituen…     

Formation of Benzyl Oxazole, A Competitive Path with the Classical Bishler-Napieralski Reaction

1,2,3,4-tetrahydroisoquinoline-3-carboxylic acids (TIC) are of considerable interest due to their biological activity and as an important structural element in several important alkaloids and other medically useful products1. Moreover, TIC is a phenylalanine analogue in which the dihedral angle is limited to a very small range because of its bicyclic nature2. In connection with the design of topographically constrained peptides, TIC has been utilized in several instance as a replacement o…