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41.
The current status of the search for localized domains of disoriented chiral condensates (DCC) in Pb+Pb collisions at 158A GeV/c are presented. A new method based on the discrete wavelet transformation (DWT) technique along with an analysis of correlation between charged and neutral particles has been used for the search of localized DCC domains. We show that both the methods indicate the presence of non-statistical fluctuations in data. 相似文献
42.
A CO(2) laser extraction system is described for in situ delta(13)C analysis of organic and inorganic materials. Carbonaceous compounds volatilized by the laser are quantitatively converted to CO(2) gas by a combustion furnace mounted after the sample chamber. Gases produced by the laser and combustion processes are swept by helium carrier gas and separated by a packed gas chromatography column prior to their introduction to an isotope ratio monitoring mass spectrometer. A sample of lentil bean was analyzed at a spatial resolution of 200 μm and yielded delta(13)C values with precision of +/- 0.3 per thousand. The accuracy of delta(13)C measurements was better than +/- 0.5 per thousand from NBS 22 (mineral oil), USGS 24 (graphite), and IAEA CO-1 (calcium carbonate). Copyright 1999 John Wiley & Sons, Ltd. 相似文献
43.
Diabetes mellitus is a chronic disease affecting the globe and its incidence is increasing pandemically. The use of plant-derived natural products for diabetes management is of great interest. Polar fraction of Artemisia annua L. leaves has shown antidiabetic activity in vivo. In the present study, three major compounds were isolated from this polar fraction; namely, 3,5-dicaffeoylquinic acid (1); 4,5-dicaffeoylquinic acid (2), and 3,4- dicaffeoylquinic acid methyl ester (3), using VLC-RP-18 and HPLC techniques. The potential protective effects of these compounds against diabetes and its complications were investigated by employing various in vitro enzyme inhibition assays. Furthermore, their antioxidant and wound healing effectiveness were evaluated. Results declared that these dicaffeoylquinic acids greatly inhibited DPPIV enzyme while moderately inhibited α-glucosidase enzyme, where compounds 1 and 3 displayed the most prominent effects. In addition, compound 3 showed pronounced inhibition of α-amylase enzyme. Moreover, these compounds markedly inhibited aldose reductase enzyme and exerted powerful antioxidant effects, among which compound 3 exhibited the highest activity implying a notable potentiality in impeding diabetes complications. Interestingly, compounds 2 and 3 moderately accelerated scratch wound healing. Our findings suggest that these dicaffeoylquinic acids can be promising therapeutic agents for managing diabetes and its complications. 相似文献
44.
Mai E. Hussein Osama G. Mohamed Ahlam M. El-Fishawy Hesham I. El-Askary Amira S. El-Senousy Ahmed A. El-Beih Eman S. Nossier Ahmed M. Naglah Abdulrahman A. Almehizia Ashootosh Tripathi Ahmed A. Hamed 《Molecules (Basel, Switzerland)》2022,27(3)
The rapid spread of bacterial infection caused by Staphylococcus aureus has become a problem to public health despite the presence of past trials devoted to controlling the infection. Thus, the current study aimed to explore the chemical composition of the extract of endophytic fungus Aspergillus fumigatus, isolated from Albizia lucidior leaves, and investigate the antimicrobial activity of isolated metabolites and their probable mode of actions. The chemical investigation of the fungal extract via UPLC/MS/MS led to the identification of at least forty-two metabolites, as well as the isolation and complete characterization of eight reported metabolites. The antibacterial activities of isolated metabolites were assessed against S. aureus using agar disc diffusion and microplate dilution methods. Compounds ergosterol, helvolic acid and monomethyl sulochrin-4-sulphate showed minimal inhibitory concentration (MIC) values of 15.63, 1.95 and 3.90 µg/mL, respectively, compared to ciprofloxacin. We also report the inhibitory activity of the fungal extract on DNA gyrase and topoisomerase IV, which led us to perform molecular docking using the three most active compounds isolated from the extract against both enzymes. These active compounds had the required structural features for S. aureus DNA gyrase and topoisomerase IV inhibition, evidenced via molecular docking. 相似文献
45.
P. Marage M. Aderholz P. Allport N. Armenise J. P. Baton M. Berggren D. Bertrand V. Brisson F. W. Bullock W. Burkot M. Calicchio E. F. Clayton T. Coghen A. M. Cooper-Sarkar O. Erriquez P. J. Fitch J. Guy F. Hamisi P. O. Hulth G. T. Jones P. Kasper U. F. Katz H. Klein E. Matsinos R. P. Middleton D. B. Miller M. M. Mobayyen D. R. O. Morrison M. Neveu S. W. O'Neale M. A. Parker P. Petiau J. Sacton R. A. Sansum N. Schmitz E. Simopoulou C. Vallée K. Varvell A. Vayaki W. Venus H. Wachsmuth J. Wells W. Wittek BEBC WA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1987,35(3):275-282
Coherent production ofρ ? mesons in charged current antineutrino interactions on neon nuclei is studied in the BEBC bubble chamber exposed to the CERN SPS wide band beam. The cross section is measured to be (95±25)·10?40 cm2 per neon nucleus, averaged over the beam energy spectrum. The distributions of kinematical variables and the absolute value of the cross section are in agreement with theoretical predictions based on the CVC hypothesis and the vector meson dominance model. 相似文献
46.
P. J. Fitch P. Kasper A. M. Cooper-Sarkar M. Aderholz N. Armenise T. Azemoon D. Bertrand M. Berggren F. W. Bullock M. Calicchio E. F. Clayton T. Coghen O. Erriquez G. Gerbier J. Guy P. O. Hulth G. Iaselli G. T. Jones M. Lagraa P. Marage R. P. Middleton D. Miller M. M. Mobayyen M. Neveu S. W. O'Neale M. A. Parker R. A. Sansum E. Simopoulou K. Varvell C. Vallée A. Vayaki W. Venus H. Wachsmuth W. Wittek J. Wells E. Zevgolatakos BEBC WA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1986,31(1):51-58
Evidence for a significant higher twist contribution to highz π? production in antineutrino scattering is presented. In events withW>3 GeV andQ 2>1 GeV2 in our data, it accounts for (51 ±8)% of all π? withz above 0.5. It is consistent with thez?Q 2 correlations of Berger's higher twist prediction. The data are inconclusive concerning the predictedy?z correlation andp T dependence. Thez ?Q 2 correlation is not adequately described by the Lund Monte-Carlo. 相似文献
47.
We have measured the polarization of ∧ and Ξ? hyperons produced inclusively by a Σ? beam of 340 GeV/c momentum in nuclear targets, using samples of 9.5 million ∧ decays and 880000 Ξ? decays. The large statistics allowed a two-dimensional analysis as functions ofx F andp t . The polarization w.r.t. the production normal is mainly positive for ∧ and negative for Ξ?. The positive sign of the ∧ polarization is opposite to predictions. Atp t >1 Gev/c, the ∧ polarization decreases to zero or even negative values, in sharp contrast to the plateau abovep t <1 GeV/c observed in inclusive ∧ production by protons. No such effect is observed for the Ξ? polarization, and its sign is as expected. 相似文献
48.
R. Albrecht T. C. Awes C. Baktash P. Beckmann F. Berger R. Bock G. Claesson G. Clewing L. Dragon A. Eklund R. L. Ferguson A. Franz S. Garpman R. Glasow H. ?. Gustafsson H. H. Gutbrod J. Idh P. Jacobs K. H. Kampert B. W. Kolb P. Kristiansson I. Y. Lee H. L?hner I. Lund F. E. Obenshain A. Oskarsson I. Otterlund T. Peitzmann S. Persson F. Plasil A. M. Poskanzer M. Purschke H. G. Ritter S. Saini R. Santo H. R. Schmidt T. Siemiarczuk S. P. Sorenseh E. Stenlund M. Tincknell G. R. Young WA -Collaboration 《Zeitschrift fur Physik C Particles and Fields》1990,45(4):529-537
Charged pion yields and transverse energies of baryons are measured for the reaction16O+Cu, Ag, Au at 60 and 200A GeV bombarding energy in the target fragmentation region employing the Plastic Ball detector. Only little dependence of the measured quantities on the bombarding energy is found. The data are compared with the multi-chain fragmentation model of Ranft. As a result it turns out that a leading order formation zone cascade is not sufficient to explain the baryon yield and the transverse energies of baryons in the target fragmentation region. 相似文献
49.
M. Bonesini E. Bonvin P. S. L. Boóth D. Bortoletto L. J. Carroll A. J. Cass D. Cavalli G. Costa M. Donnat P. A. Dorsaz D. N. Edwards J. R. Fischer L. Fluri D. Frame F. Gianotti S. Jack J. N. Jackson M. Kelly M. N. Kienzle-Focacci R. Lucock J. G. Lynch L. Mandelli M. Martin L. Mathys A. Maxwell M. Mazzanti J. J. Myerscough P. J. Negus S. Pensotti-Rancoita L. Perini D. Perrin G. Polesello W. H. Range L. Rosselet S. W. Snow M. Tamborini A. S. Thompson R. M. Turnbull J. Wells M. Werlen WA -Collaboration 《Zeitschrift fur Physik C Particles and Fields》1988,37(4):535-544
The inclusive cross sections for prompt photon production by π? and π+ on protons have been measured with a beam momentum of 280 GeV/c using a fine grained electromagnetic calorimeter and the CERN Omega spectrometer. The transverse momentum and Feynmanx F ranges covered are 4.0<p T <7.0GeV/c and ?0.45<x F <0.55 respectively. A quantitative comparison of the prompt photon cross section with next-to-leading order QCD predictions using Duke and Owens structure functions is performed. 相似文献
50.
R. Albrecht T. C. Awes C. Baktash P. Beckmann F. Berger R. Bock G. Claesson L. Dragon R. L. Ferguson A. Franz S. Garpmann R. Glasow H. A. Gustafsson H. H. Gutbrod K. H. Kampert B. W. Kolb P. Kristiansson I. Y. Lee H. Lohner I. Lund F. E. Obenshain A. Oskarsson I. Otterlund T. Peitzmann S. Persson F. Plasil A. M. Poskanzer M. Purschke H. G. Ritter R. Santo H. R. Schmidt T. Siemiarczuk S. P. Sorensen E. Stenlund G. R. Young WA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1988,38(1):3-14
Results based on calorimetric measurements are presented from reactions of 60A GeV and 200A GeV16O projectiles with C, Cu, Ag, and Au nuclei. Minimum-bias cross sections are discussed. Energy spectra measured at zero degrees and transverse-energy distributions for the pseudorapidity range 2.4≦η≤5.5 are shown. An analysis of the average transverse energy in terms of the number of participating nucleons and the number of binary nucleon-nucleon collisions is presented. Estimates of nuclear stopping and of attained energy densities are made. 相似文献