Photoproduction of pi0 omega off protons for E(gamma) < 3 GeV

Differential and total cross-sections for photoproduction of gamma proton to proton pi0 omega and gamma proton to Delta+ omega were determined from measurements of the CB-ELSA experiment, performed at the electron accelerator ELSA in Bonn. The measurements covered the photon energy range from the production threshold up to 3GeV.Comment: 8 pages, 13 figure

Study of the reaction γp→pπ0η\gamma p\to p\pi^0\eta

The reaction $\gamma p\to p\pi^0\eta$ has been studied with the CBELSA detector at the tagged photon beam of the Bonn electron stretcher facility. The reaction shows contributions from $\Delta^+(1232)\eta$, $N(1535)^+\pi^0$ and $pa_0(980)$ as intermediate states. A partial wave analysis suggests that the reaction proceeds via formation of six $\Delta$ resonances, $\Delta(1600)P_{33}$, $\Delta(1920)P_{33}$, $\Delta(1700)D_{33}$, $\Delta(1940)D_{33}$, $\Delta(1905)F_{35}$, $\Delta(2360)D_{33}$, and two nucleon resonances $N(1880)P_{11}$ and $N(2200)P_{13}$, for which pole positions and decay branching ratios are given.Comment: 13 pages, 10 figures, 7 table

Photoproduction of eta mesons off protons for photon energies from 0.75 GeV to 3 GeV

Total and differential cross sections for the reaction p(gamma, eta)p have been measured for photon energies in the range from 750 MeV to 3 GeV. The low-energy data are dominated by the S11 wave which has two poles in the energy region below 2 GeV. Eleven nucleon resonances are observed in their decay into p eta. At medium energies we find evidence for a new resonance N(2070)D15 with (mass, width) = (2068+-22, 295+-40) MeV. At photon energies above 1.5 GeV, a strong peak in forward direction develops, signalling the exchange of vector mesons in the t channel.Comment: LaTeX, 4 pages including 4 eps-figures, submitted to Phys. Rev. Lett. The publication of hep-ex/0311045 is accompanied by hep-ex/0407022 on photoproduction of neutral pions, submitted to Phys. Rev. Lett. Fits published in the latest version are based on additional data, new beam asymmetry data from GRAAL are included, for instance. The data demanded more resonant contributions which were studied in detail. PWA reference adde

Neutral pion photoproduction off protons in the energy range 0.3 GeV < E(gamma) < 3 GeV

Single pi0 photoproduction has been studied with the CB-ELSA experiment at Bonn using tagged photon energies between 0.3 and 3.0 GeV. The experimental setup covers a very large solid angle of about 98% of 4 pi. Differential cross sections (d sigma)/(d Omega) have been measured. Complicated structures in the angular distributions indicate a variety of different resonances being produced in the s channel intermediate state gamma p --> N* (Delta*) --> p pi0. A combined analysis including the data presented in this letter along with other data sets reveals contributions from known resonances and evidence for a new resonance N(2070)D15.Comment: LaTeX file, 4 pages, 4 encapsulated postscript figures, submitted to Phys. Rev. Lett. The publication of hep-ex/0407022 is accompanied by hep-ex/0311045 on photoproduction of eta mesons. Reference [3]: changed, reference [17]: citation added. Figure 3, 4: SAID added up to 2 GeV for comparison, update

UDP-glucose 4, 6-dehydratase Activity Plays an Important Role in Maintaining Cell Wall Integrity and Virulence of Candida albicans

Candida albicans, a human fungal pathogen, undergoes morphogenetic changes that are associated with virulence. We report here that GAL102 in C. albicans encodes a homolog of dTDP-glucose 4,6-dehydratase, an enzyme that affects cell wall properties as well as virulence of many pathogenic bacteria. We found that GAL102 deletion leads to greater sensitivity to antifungal drugs and cell wall destabilizing agents like Calcofluor white and Congo red. The mutant also formed biofilms consisting mainly of hyphal cells that show less turgor. The NMR analysis of cell wall mannans of gal102 deletion strain revealed that a major constituent of mannan is missing and the phosphomannan component known to affect virulence is greatly reduced. We also observed that there was a substantial reduction in the expression of genes involved in biofilm formation but increase in the expression of genes encoding glycosylphosphatidylinositol-anchored proteins in the mutant. These, along with altered mannosylation of cell wall proteins together might be responsible for multiple phenotypes displayed by the mutant. Finally, the mutant was unable to grow in the presence of resident peritoneal macrophages and elicited a weak pro-inflammatory cytokine response in vitro. Similarly, this mutant elicited a poor serum pro-inflammatory cytokine response as judged by IFNγ and TNFα levels and showed reduced virulence in a mouse model of systemic candidiasis. Importantly, an Ala substitution for a conserved Lys residue in the active site motif YXXXK, that abrogates the enzyme activity also showed reduced virulence and increased filamentation similar to the gal102 deletion strain. Since inactivating the enzyme encoded by GAL102 makes the cells sensitive to antifungal drugs and reduces its virulence, it can serve as a potential drug target in combination therapies for C. albicans and related pathogens

N* and Delta* decays into N pi0 pi0

Decays of baryon resonances in the second and the third resonance region into N pi0 pi0 are studied by photoproduction of two neutral pions off protons. Partial decay widths of N* and Delta* resonances decaying into Delta(1232) pi, N(\pi\pi)_{S}, N(1440)P_{11} pi, and N(1520)D_{13} pi are determined in a partial wave analysis of this data, and data from other reactions. Several partial decay widths were not known before. Interesting decay patterns are observed which are not even qualitatively reproduced by quark model calculations. In the second resonance region, decays into Delta(1232) pi dominate clearly. The N(\pi\pi)_{S}-wave provides a significant contribution to the cross section, especially in the third resonance region. The P_{13}(1720) properties found here are at clear variance to PDG values.Comment: 13 pages, 4 figures, long author's lis

Early detection of widespread progressive brain injury after cardiac arrest: a single case DTI and post-mortem histology study.

OBJECTIVE: We tested the hypothesis in sense of a proof of principle that white matter (WM) degeneration after cardiopulmonary arrest (CPA) can be assessed much earlier by diffusion tensor imaging (DTI) than by conventional MRI. METHODS: We performed DTI and T2-weighted FLAIR imaging over four serial acquisitions of a 76-year-old man with unresponsive wakefulness syndrome at day 41, 75, 173 and 284 after CPA. DTI was also performed in ten healthy control subjects. Fractional anisotropy (FA) derived from DTI was assessed in eleven regions of interest within the cerebral white matter (WM) and compared with post-mortem neuropathological findings. RESULTS: In contrast to conventional FLAIR images that revealed only circumscribed WM damage, the first DTI demonstrated significant reduction of FA across the whole WM. The following FLAIR images (MRI 2-4) revealed increasing atrophy and leukoaraiosis paralleled by clinical deterioration with reduction of wakefulness and intractable seizures. Neuropathological findings confirmed the widespread and marked brain injury following CPA. CONCLUSION: DTI may help to evaluate microstructural brain damage following CPA and may have predictive value for further evolution of cerebral degeneration in the chronic phase after CPA

The control subjects' and the patient's mean FA values of different ROIs as calculated from DTI. Significance levels (* p<0.05, ** p<0.001, *** p<0.0001).

<p>The control subjects' and the patient's mean FA values of different ROIs as calculated from DTI. Significance levels (* p<0.05, ** p<0.001, *** p<0.0001).</p

Examples of histopathologic findings.

<p>A: Pannecrosis, parietal lobe. HE stain. B: Neuronal necrosis (arrow), frontal lobe. HE stain. C: glial scarring of the white matter. GFAP stain. D: Inflammation of the white matter (black arrows: macrophages, black arrow head: microglia). CD68 stain. E: Patchy loss of myelin structure in the occipital lobe. Klüver-Barrera stain. F: Astrogliosis of the putamen (white arrow heads: astrozytes). GFAP stain.</p