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7Be(p, $\gamma$ )8B has an important role in nuclear astrophysics, having a direct impact on both the high energy component of solar neutrinos and the 7Li abundance after the Big Bang Nucleosynthesis. All direct measurements providing useful information on this reaction so far used the same approach, i.e. a proton beam on a radioactive 7Be target. The overall precision and accuracy of the estimate of the astrophysical rate of this reaction are limited by the discrepancy between the results of existing measurements, possibly due to the complicated stoichiometry and beam induced deterioration of the radioactive targets. The ERNA (European Recoil separator for Nuclear Astrophysics) collaboration planned a new experiment in inverse kinematics exploiting the intense 7Be beam available at CIRCE (Center for Isotopic Research on Cultural and Environmental heritage), Caserta, Italy. The 8B recoils are produced in a windowless hydrogen gas target and detected after the efficient mass separation provided by ERNA. Here we present the commissioning of the experimental setup and a first cross section measurement at $E_{\mathrm{cm}}\approx 812$ keV.

Background: The origin of fluorine is a widely debated issue. Nevertheless, the $^{15}\mathrm{N}(\ensuremath{\alpha},\ensuremath{\gamma})^{19}\mathrm{F}$ reaction is a common feature among the various production channels so far proposed. Its reaction rate at relevant temperatures is determined by a number of narrow resonances together with the direct capture and the tails of the two broad resonances at ${E}_{\mathrm{c}.\mathrm{m}.}=1323$ and 1487 keV.Purpose: The broad resonances widths, ${\mathrm{\ensuremath{\Gamma}}}_{\ensuremath{\gamma}}$ and ${\mathrm{\ensuremath{\Gamma}}}_{\ensuremath{\alpha}}$, have to be measured with adequate precision in order to better determine their contribution to the $^{15}\mathrm{N}(\ensuremath{\alpha},\ensuremath{\gamma})^{19}\mathrm{F}$ stellar reaction rate.Methods: Measurement through the direct detection of the $^{19}\mathrm{F}$ recoil ions with the European Recoil separator for Nuclear Astrophysics (ERNA) were performed. The reaction was initiated by a $^{15}\mathrm{N}$ beam impinging onto a $^{4}\mathrm{He}$ windowless gas target. The observed yield of the resonances at ${E}_{\mathrm{c}.\mathrm{m}.}=1323$ and 1487 keV is used to determine their widths in the $\ensuremath{\alpha}$ and $\ensuremath{\gamma}$ channels.Results: We show that a direct measurement of the cross section of the $^{15}\mathrm{N}(\ensuremath{\alpha},\ensuremath{\gamma})^{19}\mathrm{F}$ reaction can be successfully obtained with the recoil separator ERNA, and the widths ${\mathrm{\ensuremath{\Gamma}}}_{\ensuremath{\gamma}}$ and ${\mathrm{\ensuremath{\Gamma}}}_{\ensuremath{\alpha}}$ of the two broad resonances have been determined. While a fair agreement is found with earlier determination of the widths of the 1487 keV resonance, a significant difference is found for the 1323 keV resonance ${\mathrm{\ensuremath{\Gamma}}}_{\ensuremath{\alpha}}$.Conclusions: The revision of the widths of the two more relevant broad resonances in the $^{15}\mathrm{N}(\ensuremath{\alpha},\ensuremath{\gamma})^{19}\mathrm{F}$ reaction presented in this work is the first step toward a more firm determination of the reaction rate. At present, the residual uncertainty at the temperatures of the $^{19}\mathrm{F}$ stellar nucleosynthesis is dominated by the uncertainties affecting the direct capture component and the 364 keV narrow resonance, both so far investigated only through indirect experiments.

The astrophysical S-factor of 14N(p,gamma)15O has been measured for effective center-of-mass energies between E_eff = 119 and 367 keV at the LUNA facility using TiN solid targets and Ge detectors. The data are in good agreement with previous and recent work at overlapping energies. R-matrix analysis reveals that due to the complex level structure of 15O the extrapolated S(0) value is model dependent and calls for additional experimental efforts to reduce the present uncertainty in S(0) to a level of a few percent as required by astrophysical calculations., Comment: Eur. Phys. J. A, accepted. 17 pages, 15 figures

For improved cross-section measurements of the reaction 12C(α,γ)16O in inverted kinematics, a recoil separator ERNA is developed at the 4MV Dynamitron tandem accelerator in Bochum to detect directly the 16O recoils with high efficiency. Due to the emission of the capture γ-rays, the kinematically forward directed 16O recoils are described by an angle and energy spread. Thus, the acceptances in angle and energy of ERNA must cover these spreads in order to extract reliable cross-section values. We report on such acceptance measurements over the energy range Ecm=0.7-5.0 MeV, using an 16O pilot beam. © 2003 Elsevier B.V. All rights reserved.

Non-radiative transitions in nuclear capture reactions between light nuclei play a relevant role in stellar nuclear astrophysics, where nuclear processes occur at typical energies from tens to hundreds of keV. At higher energies, instead, the E0 contributions may be shadowed by more intense transitions. The experimental study of E0 transitions requires a specific detection setup, able to uniquely identify events where an electron-positron pair is produced. A compact ΔE-E charged-particle spectrometer based on two silicon detectors has been designed to be installed in the jet gas target chamber of the recoil mass separator ERNA (European Recoil separator for Nuclear Astrophysics) at the CIRCE laboratory of Caserta, Italy. The detector design, its performances and the first foreseen applications are described.

Stellar models show an exceptional sensitivity on the cross section of 12C( α , γ )16O and a precision of about 10% is required to provide adequate constraints on stellar evolution. A measurement at the astrophysical energy, E 0 ≈ 300 keV , is unfeasible due to the extremely low cross section. Furthermore, the extrapolation of existing high-energy data is complicated by a complex reaction scheme. Besides direct measurements of 12C( α , γ )16O, the β-delayed α-decay of 16N and 12C + 4He elastic scattering provide additional information for the relevant 16O levels. In this Letter we present a new R-matrix analysis, where systematic uncertainties of the included data sets, in particular the absolute normalization, were treated in the fitting procedure. The data were selected according to rigorous criteria in order to reduce uncontrolled systematic effects and, finally, a Monte Carlo approach was used to evaluate the uncertainty at astrophysical energy. The resulting S factor, S ( 300 ) = 161 ± 19 stat − 2 sys + 8 keV b , is, for the first time, close to the required precision.

The radiative capture reaction C 12 ( α , γ ) O 16 has been investigated in the energy range E = 3.3 to 4.5 MeV. This experiment focused in particular on the cascade transition to the 0+ state at E x = 6.05 MeV in 16O and was performed by detecting the capture γ-rays with a NaI detector array at the windowless 4He gas target of the recoil mass separator ERNA in coincidence with the 16O ejectiles. The 6.05 MeV transition has been considered recently as a component accounting for up to 15% of the C 12 ( α , γ ) O 16 total cross section at astrophysical energies. The arrangement of the detector array yielded additional information on the γ-ray multipolarity, i.e. the ratio σ E 2 / σ E 1 , and it was found that the 6.05 MeV transition is entirely E2 in the studied energy range. The results for this transition are analyzed in an R-matrix formalism and extrapolated to the relevant Gamow energy of stellar helium burning, E 0 ≃ 300 keV . In contrast to a previous analysis, the present extrapolation suggests a negligible contribution from this amplitude, S 6.05 ( 300 ) 1 keV b . Additional data for cascade transitions to excited states at E x = 6.13 , 6.92, and 7.12 MeV, respectively, as well as to the ground state were obtained and the corresponding S factors in the studied energy range are given.

Toxoplasmic encephalitis (TE) continues to be a severe health problem despite the introduction of highly active antiretroviral therapy (HAART). To identify predictors for development of TE we compared demographic, clinical and diagnostic variables in AIDS patients with TE before (n = 102) or after the introduction (n = 70) of HAART at the Charité University Medicine in Berlin, Germany. Interestingly, patient characteristics did not differ significantly in the pre- and post-HAART groups. Sixty-eight percent of patients had CD4-cell counts of50/μl. Outcome after treatment with pyrimethamin plus sulfonamides or clindamycin (47% each) did not differ; adverse reactions were more frequent in patients receiving sulfonamides than in those receiving clindamycin (25% vs. 10.5%; p = 0.02). Interestingly, patients in the post HAART group had not received (82.9%) or had not taken HAART adequately (17.1%). Concurrent diagnosis of TE and HIV was significantly more often in the post- compared to the pre-HAART group (49 vs. 26%, respectively; p 0.001). Thus, despite the introduction of HAART, awareness of opportunistic infections in HIV patients is warranted. High rates of unawareness of HIV infection should make public health efforts focus on early identification of HIV infection and initiation of and compliance with HAART.

For improved measurements of the key astrophysical reaction C-12(alpha, gamma)O-16 in inverted kinematics, a recoil separator ERNA is being developed at the 4 MV Dynamitron tandem accelerator in Bochum to detect directly the O-16 recoils with about 50% efficiency. Calculations of the ion beam optics including all filtering and focusing elements of ERNA are presented. Since the C-12 projectiles and the O-16 recoils have essentially the same momentum, and since the C-12 ion beam emerging from the accelerator passes through a momentum filter (analysing magnet), the C-12 ion beam must be as free as possible from O-16 contamination for ERNA to succeed. In the present work, the O-16 contamination was reduced from a level of 1 x 10(-11) to a level below 2 x 10(-29) by the installation of Wien filters both before and after the analysing magnet. The measurement of these and other beam specifications involved other parts of the final ERNA layout - sequentially a Wien filter, a 60 degrees dipole magnet, another Wien filter, and a Delta E-E telescope. The setup led to a measured suppression factor of 5 x 10(-18) for the C-12 ion beam. The experiments also indicate that an almost free choice of the charge state for the O-16 recoils is possible in the separator.

(7)Be decays via electron capture and therefore its half-life is expected to depend on the electron density at the nucleus. We measured the (7)Be half-life in palladium, tungsten, zirconium and tantalum metals, in order to investigate the influence of the quasi-free electrons in metals on the probability of electron capture. The (7)Be samples were obtained implanting a 4.85 MeV pure radioactive (7)Be ion beam. The (7)Be half-life was determined measuring the 478 keV gamma decay following the electron capture by means of HPGe detectors. In order to reduce systematic errors, we planned to perform independent measurements in three different laboratories: Naples (Italy), Bochum (Germany) and Debrecen (Hungary). On the basis of the first results, we do not find a (7)Be half-life change within the experimental errors of 0.4%. RI Fulop, Zsolt/B-2262-2008

The electron screening in the 7Li ( p , α ) α reaction has been studied at E p = 30 to 100 keV for different environments: Li2WO4 insulator, Li metal, and PdLi alloys. For the insulator a screening potential energy of U e = 185 ± 150 eV was observed, consistent with previous work and the atomic adiabatic limit. However, for the Li metal and the PdLi alloys we find large values of U e = 1280 ± 60 and 3790 ± 330 eV , respectively: the values can be explained by the plasma model of Debye applied to the quasi-free metallic electrons in these samples. Similar results have been found for the 6Li ( p , α ) 3 He reaction supporting the hypothesis of the isotopic independence of the electron screening effect. The data together with previous studies of d ( d , p ) t and 9Be ( p , α ) 6 Li in metals verify the Debye model scaling U e ∝ Z t (charge number of target).

The astrophysically relevant 3 He ( d , p ) 4 He reaction was indirectly studied by means of the Trojan Horse Method applied to the 6 Li ( 3 He , pα ) 4 He three body process performed at 5 and 6 MeV. The bare astrophysical S(E)-factor extracted in Modified Plane Wave Born Approximation was compared with the free behaviour and an independent estimate of the screening potential was obtained, confirming the discrepancy with the adiabatic limit.

PURPOSE To compare virtual with flexible bronchoscopy for the detection of bronchial stenoses. MATERIALS AND METHODS In a retrospective study, we compared the results of 26 patients, who had clinical suspected pathologies of the tracheobronchial airways and underwent both flexible bronchoscopy and multislice CT with 3D surface rendering of the airways. Flexible bronchoscopy and virtual bronchoscopy were compared as to the rate of detecting bronchial stenoses. For statistical analysis, we divided the tracheobronchial tree in the following sections: trachea, 2 main bronchi, 6 lobar bronchi, 18 segmental bronchi and 36 subsegmental bronchi, corresponding to 63 bronchial sections for each patient (on average) and a total of 1638 bronchial sections for all 26 patients. We graded the bronchial stenosis as less than 50 %, as 50 to 95 % and as complete obstruction. RESULTS Virtual bronchoscopy detected 25 bronchial stenoses, while flexible bronchoscopy only revealed 17 stenoses. Stenoses with a diameter less than 50 % were found with virtual bronchoscopy 14 times and with flexible bronchoscopy 10 times. Stenoses with a diameter between 50 and 95 % were detected 7 and 4 times, respectively, and complete obstructions 4 and 3 times, respectively. Tracheobronchial stenoses were well recognized with virtual bronchoscopy. Moreover, the virtual method enabled the visualization of high-grade stenoses and post-stenotic areas that could not be passed by the fiberoptic bronchoscope. Virtual bronchoscopy detected stenoses at a higher rate but the difference was not statistically significant (stenoses < 50 %: p = 0.352, 50 - 95 %: p = 0.339, complete obstruction: p = 0.696). CONCLUSION Virtual bronchoscopy is a useful non-invasive method for the diagnostic evaluation of the tracheobronchial tree. In comparison with flexible bronchoscopy, virtual bronchoscopy is superior in revealing high-grade stenoses and visualizing post-stenotic areas.

The recoil separator ERNA (European Recoil Separator for Nuclear Astrophysics) for improved measurements of the astrophysical key reaction C-12(alpha, gamma)O-16 is being developed at the 4 MV Dynamitron tandem accelerator in Bochum to detect directly the O-16 recoils. The total detection efficiency of about 50 % allows direct measurements in a much wider energy range than previously accessible. In addition this technique allows improved measurements not hampered by cosmic background problems when compared to gamma -ray detection.

The efficacy, safety, and tolerability of voriconazole and fluconazole were compared in 391 immunocompromised patients with mycology- and biopsy-proven esophageal candidiasis. Primary efficacy analysis (256 patients) of esophageal treatment as assessed by esophagoscopy revealed success rates of 98.3% with voriconazole and 95.1% with fluconazole. The 95% confidence interval for the difference in success rates ranged from -1.0% to 7.5%. The overall safety and tolerability of both antifungals were acceptable. Fewer patients discontinued voriconazole treatment because of insufficient clinical response (4 patients [2.0%] vs. 5 patients [2.6%]). More patients discontinued voriconazole than fluconazole treatment because of laboratory test abnormalities (7 patients [3.5%] vs. 2 patients [1.0%]) or treatment-related adverse events (5 patients [2.5%] vs. 1 patient [0.5%]). The most frequent adverse events (23%) with voriconazole were mild, transient visual disturbances. Voriconazole (200 mg, b.i.d.) was shown to be at least as effective as fluconazole in the treatment of biopsy-proven esophageal candidiasis in immunocompromised patients.

Understanding the electron screening effect in the laboratory is critical for a correct interpretation of low‐energy nuclear reactions in stars. Extensive studies of the electron screening effect in deuterated metals (54 metals) and other environments have been carried out in Bochum in the last 4 years. Experimental results of anomalous enhancements have been interpreted in terms of the Debye plasma model applied to quasi‐free metallic electrons. For the d(d,p)t reaction in metallic environments, the variation of hydrogen solubility in the samples as a function of temperature has also been measured, showing an anti‐correlation with screening enhancement as expected. Within this model, the deduced number of valence electrons per metallic atom also agrees with the corresponding number from the Hall coefficient. Recently, the expected temperature dependence of the screening potential has been verified together with the expected Zt scaling (with the metallic host) of the Debye radius. Preliminary results on the 7Li(p,α) and 6Li(p,α) reactions in Li2WO4 insulator, Li metal and PdLi alloys confirm the expected behaviour of the screening effect and further supports the applicability of the Debye model. Indeed, the proposed model also accounts for the high screening potential (Ue = 900±50 eV) observed in previous studies of the reactions 9Be(p,α) and 9Be(p,d), which was not understood at the time. A review of all these results will be presented.

For the electron capture of Be-7 in the metallic environments Pd and In the Be-7 half-life was observed to increase by 0.9 +/- 0.2 and 0.7 +/- 0.2%, respectively, while in the insulator Li2O it was unchanged within experimental error (all samples cooled to T = 12K). The observations are consistent with the predictions of the Debye plasma model applied to the quasi-free electrons in the metals.

C( 12 C;a) 20 Ne and 12 C( 12 C; p) 23 Na are the most important reactions during the carbon burning phase in stars. Direct measurements at the relevant astrophysical energy (E=1.5 0.3MeV) are very challenging because of the extremely small cross sections involved and of the high beam-induced background originating from impurities in the targets. In addition, persistent resonant structures at low energies are not well understood and make the extrapolation of the cross section from high energy data very uncertain. As a preliminary step towards the measurements of the 12 C( 12 C;a) 20 Ne and 12 C( 12 C; p) 23 Na reactions we intend to investigate the behaviour of targets under beam bombardment, specifically the quantitative measurement of hydrogen and deuterium content of highly pure stable carbon targets in relation to target temperature. Experiments are taking place at the CIRCE accelerator in Caserta, Italy and preliminary results are presented here.

Exhaust emissions from a motorway have been monitored for a year in a joint project by the State of Lower Saxony and Volkswagen. Measurements were performed by the Fraunhofer Institut fur Toxikologie und Aerosolforschung in Hannover. As dispersion models alone are unable to reproduce the behaviour of nitrogen oxides and ozone, a simplified air parcel model has been developed. This model includes, in addition to pure dispersion, some basic reactions of nitrogen oxides and ozone, but neglects reactions with hydrocarbons. A comparison with the observed concentrations shows that the model gives acceptable results if some restrictions with respect to meteorological conditions are taken into account.

Despite the great amount of literature concerning toxoplasmic encephalitis in AIDS patients, little is known about extracerebral toxoplasmosis. Therefore we conducted a study of 80 autopsy cases to estimate the frequency of extracerebral toxoplasmosis. A control group of 50 cases was completely negative for all markers applied. In 35 of the 80 AIDS-cases (43.7%), organisms could be detected. In 13 cases (16.2%) there was an extracerebral toxoplasmosis; 4 cases (5%) showed only extracerebral involvement and in 9 cases (11.2%), extracerebral toxoplasmosis occurred in combination with cerebral manifestations. In 22 cases (27.5%), only cerebral toxoplasmosis was found. The following organs were involved: cardiac muscle (15%), lungs (6.2%), liver (5%), pancreas (5%), gastrointestinal tract (6.2%), adrenal glands (5%), lymph nodes (5%) and testis (3.7%). In individual cases further organs, not mentioned above, were involved. Pseudocysts could be demonstrated within necroses and inflammatory foci by conventional staining, whereas trophozoites became apparent only immunohistologically.

The 3He(alpha,gamma)7Be reaction presently represents the largest nuclear uncertainty in the predicted solar neutrino flux and has important implications on the big bang nucleosynthesis, i.e., the production of primordial 7Li. We present here the results of an experiment using the recoil separator ERNA (European Recoil separator for Nuclear Astrophysics) to detect directly the 7Be ejectiles. In addition, off-beam activation and coincidence gamma-ray measurements were performed at selected energies. At energies above 1 MeV a large discrepancy compared to previous results is observed both in the absolute value and in the energy dependence of the cross section. Based on the available data and models, a robust estimate of the cross section at the astrophysical relevant energies is proposed.

The 3He(alpha,gamma)7Be reaction presently represents the largest nuclear uncertainty in the predicted solar neutrino flux and has important implications on the big bang nucleosynthesis, i.e., the production of primordial 7Li. We present here the results of an experiment using the recoil separator ERNA (European Recoil separator for Nuclear Astrophysics) to detect directly the 7Be ejectiles. In addition, off-beam activation and coincidence gamma-ray measurements were performed at selected energies. At energies above 1 MeV a large discrepancy compared to previous results is observed both in the absolute value and in the energy dependence of the cross section. Based on the available data and models, a robust estimate of the cross section at the astrophysical relevant energies is proposed.

We report on a new lifetime measurement of the ${E}_{x}=6792$ keV state in $^{15}\mathrm{O}$ via the Doppler-shift attenuation method at the $E=259$ keV resonance in the reaction $^{14}\mathrm{N}$($p,\ensuremath{\gamma}$)$^{15}\mathrm{O}$. This subthreshold state is of particular importance for the determination of the ground state astrophysical $S$ factor of $^{14}\mathrm{N}$($p,\ensuremath{\gamma}$)$^{15}\mathrm{O}$ at stellar energies. The measurement technique has been significantly improved over that used in previous work. The conclusion of a finite lifetime drawn there cannot be confirmed with the present data. In addition, the lifetimes of the two states at ${E}_{x}=5181$ and 6172 keV have been measured with the same technique in order to verify the experimental method. We observe an attenuation factor $F(\ensuremath{\tau})g0.98$ for the ${E}_{x}=6172$ and 6792 keV states, respectively, corresponding to $\ensuremath{\tau}l0.77$ fs. The attenuation factor for the ${E}_{x}=5181$ keV state results in $F(\ensuremath{\tau})=0.78\ifmmode\pm\else\textpm\fi{}0.02$ corresponding to $\ensuremath{\tau}=8.4\ifmmode\pm\else\textpm\fi{}1.0$ fs, which is in excellent agreement with literature.

The set of fusion reactions {sup 12}C+{sup 12}C play a critical role in several astrophysical processes. In a recent experiment, the fusion reactions {sup 12}C+{sup 12}C have been studied at E{sub CM} = 2.10 to 4.75 MeV by {gamma}-ray spectroscopy using a C target of ultra-low hydrogen contamination. The deduced astrophysical S-tilde(E) factor exhibits previously unknown resonances at E{

Volkswagen has developed an on-board exhaust emissions measurement system which enables the direct and continuous determination of the mass emissions of the exhaust components HC, CO, NO x , and CO 2 , together with the real-time fuel consumption. The system can be installed in each type of passenger car and can be operated under all traffic and weather conditions. The system has proved itself in numerous on-the-road test runs. The test programs cover measurements in urban areas, on country roads, and on motor ways. The results of each test run are printed out immediately after completion of the test. As an example, some results of a high-speed motor way test program are presented.

The traffic on motorways is a source for CO, NOx and hydrocarbons. In a joined project by the state of Lower Saxony and Volkswagen the atmospheric transport of pollutants from a motorway was observed for one year. NO, NO2, CO and O3 were continuously monitored at different distances up to 600 m from the motorway, together with meteorological data. The measurements were performed by the “Fraunhofer-Institut fur Toxikologie und Aerosolforschung in Hannover”. Two models are used by Volkswagen to describe the atmospheric transport: A Gaussian dispersion model including deposition and a Lagrange-type model including selected photochemical reactions. Both models can be used to calculate the dispersion of CO and NOx taking into account the deposition of NO2. The Lagrange-type model additionally allows to calculate the concentrations of NO, NO2 and O3 under the influence of solar radiation. The applicability of the models is confined to windspeeds ≥1 m/s. Wind directions parallel to the motorway are also excluded. As the measurements show considerable fluctuations, it is necessary to perform statistical evaluations, comprising a greater number of observations. The verification is still in progress.

In the metal Cu cooled to T = 12K the alpha-decay half-life of Po-210 nuclides, located inside the metal, was measured to be shorter by 6.3 +/- 1.4% compared to that at room temperature. RI Aliotta, Marialuisa /H-2567-2012

For the β--decay of 198Au in a Au metallic environment the half-life was observed to be longer by 0.4±0.7% at room temperature (T = 293K) and by 4.0±0.7% when the metal was cooled to T = 12K, both compared to the literature value of T 1/2 = 2.6943±0.0008d.

The fusion reactions 12C(12C,alpha)20Ne and 12C(12C,p)23Na have been studied from E=2.10 to 4.75 MeV by gamma-ray spectroscopy using a C target with ultralow hydrogen contamination. The deduced astrophysical S(E)* factor exhibits new resonances at Eor =3.0 MeV, in particular, a strong resonance at E=2.14 MeV, which lies at the high-energy tail of the Gamow peak. The resonance increases the present nonresonant reaction rate of the alpha channel by a factor of 5 near T=8x10(8) K. Because of the resonance structure, extrapolation to the Gamow energy EG=1.5 MeV is quite uncertain. An experimental approach based on an underground accelerator placed in a salt mine in combination with a high efficiency detection setup could provide data over the full EG energy range.

The $^{3}\mathrm{He}$($d,p$)$^{4}\mathrm{He}$ reaction has been studied from ${E}_{c.m.}=600$ keV down to astrophysical energies by means of the ``Trojan horse'' method using the $^{6}\mathrm{Li}$($^{3}\mathrm{He}$,$p\ensuremath{\alpha}$)$^{4}\mathrm{He}$ three-body reaction at ${E}_{\mathrm{lab}}=5$ and 6 MeV. Coincidence spectra were measured in kinematic conditions favoring the quasifree $^{3}\mathrm{He}+^{2}\mathrm{H}$ process. The bare astrophysical factor ${S}_{b}(E)$ for the $^{3}\mathrm{He}$($d,p$)$^{4}\mathrm{He}$ reaction was extracted from the three-body cross section in the modified plane-wave Born approximation. Comparison with the ${S}_{b}$ extrapolation from the free two-body data is presented. The independent estimate of the screening potential as obtained with the present work seems to confirm the theoretical adiabatic limit.

As a preliminary step towards measurements of the 12C +12 C reactions at astrophysical energies, we investigate the behaviour of targets under beam bombardment, specifically the quantitative relation between hydrogen and deuterium content of different carbon targets and target temperature. Experiments have taken place at the CIRCE accelerator in Caserta, Italy and preliminary results are presented here.

The objective of the present trial was to compare the efficacy, safety, and tolerability of moxifloxacin (400 mg) given intravenously (i.v.) once daily followed by oral moxifloxacin (400 mg) for 7 to 14 days with the efficacy, safety, and tolerability of co-amoxiclav (1.2 g) administered by i.v. infusion three times a day followed by oral co-amoxiclav (625 mg) three times a day, with or without clarithromycin (500 mg) twice daily (i.v. or orally), for 7 to 14 days in adult patients with community-acquired pneumonia requiring initial parenteral therapy. A total of 628 patients were enrolled and assessed by evaluation of their clinical and bacteriological responses 5 to 7 days and 21 to 28 days after administration of the last dose of study medication. Although the trial was designed, on the basis of predefined outcomes, to demonstrate the equivalence of the two regimens, the results showed statistically significant higher clinical success rates (for moxifloxacin, 93.4%, and for comparator regimen, 85.4%; difference [Δ], 8.05%; 95% confidence interval [CI], 2.91 to 13.19%; P = 0.004) and bacteriological success rates (for moxifloxacin, 93.7%, and for comparator regimen, 81.7%; Δ, 12.06%; 95% CI, 1.21 to 22.91%) for patients treated with moxifloxacin. This superiority was seen irrespective of the severity of the pneumonia and whether or not the combination therapy included a macrolide. The time to resolution of fever was also statistically significantly faster for patients who received moxifloxacin (median time, 2 versus 3 days), and the duration of hospital admission was approximately 1 day less for patients who received moxifloxacin. The treatment was converted to oral therapy immediately after the initial mandatory 3-day period of i.v. administration for a larger proportion of patients in the moxifloxacin group than patients in the comparator group (151 [50.2%] versus 57 [17.8%] patients). There were fewer deaths (9 [3.0%] versus 17 [5.3%]) and fewer serious adverse events (38 [12.6%] versus 53 [16.5%]) in the moxifloxacin group than in the comparator group. The rates of drug-related adverse events were comparable in both groups (38.9% in each treatment group). The overall incidence of laboratory abnormalities was similar in both groups. Thus, it is concluded that monotherapy with moxifloxacin is superior to that with a standard combination regimen of a β-lactam and a β-lactamase inhibitor, co-amoxiclav, with or without a macrolide, clarithromycin, in the treatment of patients with community-acquired pneumonia admitted to a hospital.

The data on the use of tipranavir and enfuvirtide in pregnancy are very limited. We performed a pharmacokinetic profile in a pregnant woman with multidrug-resistant HIV-1 infection at 37 weeks gestation. Tipranavir levels were in the therapeutic range and the cord blood concentration at delivery was relatively high when compared with other protease inhibitors. No enfuvirtide was detected in the fetal compartment. Tipranavir and enfuvirtide were successfully used in pregnancy, but possible toxicities must be kept in mind.

Eine HIV-Infektion per se ist auch bei AIDS-Manifestation kein Grund, prinzipiell auf Reisen zu verzichten. Allerdings sollten diese unter Einkalkulieren etwaiger Gesundheits-risiken vorbereitet werden. Die Planung mus das Stadium der Erkrankung, das Reiseziel (nicht nur in tropische Regionen) und die geplanten Aktivitaten berucksichtigen. Gegebenenfalls ist ein Reisetermin zu verschieben, die Route abzuandern oder in seltenen Fallen auch von einer Reise ganz abzusehen.

For the beta(+)-decay of Na-22 in the metallic environment Pd cooled to T = 12 K the Na-22 half-life was observed to be shorter by 1.2 +/- 0.2%. The result is consistent with-but lower than-the prediction of the Debye plasma model.

Despite the great amount of literature concerning toxoplasmic encephalitis in AIDS patients, little is known about extracerebral toxoplasmosis. Therefore we conducted a study of 80 autopsy cases to estimate the frequency of extracerebral toxoplasmosis. A control group of 50 cases was completely negative for all markers applied. In 35 of the 80 AIDS-cases (43.7%), organisms could be detected. In 13 cases (16.2%) there was an extracerebral toxoplasmosis; 4 cases (5%) showed only extracerebral involvement and in 9 cases (11.2%), extracerebral toxoplasmosis occurred in combination with cerebral manifestations. In 22 cases (27.5%), only cerebral toxoplasmosis was found. The following organs were involved: cardiac muscle (15%), lungs (6.2%), liver (5%), pancreas (5%), gastrointestinal tract (6.2%), adrenal glands (5%), lymph nodes (5%) and testis (3.7%). In individual cases further organs, not mentioned above, were involved. Pseudocysts could be demonstrated within necroses and inflammatory foci by conventional staining, whereas trophozoites became apparent only immunohistologically.

6Li+-ions accelerated electrostatically to energies of 200–390 keV are electronically excited by the beam-foil technique. The emitted light is analyzed with a Seya-Namioka VUV monochromator in the wavelength range 400–1900 a. All Li II and Li III lines known from theory — in one case emitted by an=9 level — are detected, several of them for the first time. Lifetimes of 20 Li II levels, some not measured previously, are determined after correction for cascades. The accuracy of the experimental values for several lifetimes is better than that of theoretical predictions.

H 2 + ions or protons, accelerated to energies between 80 and 300 keV, are sent through a thin carbon target. Light emitted by the excited atoms moving out of the foil with a definite velocity is analyzed using interference filters and a cooled photomultiplier. Intensities of theH α,H β, andH γ lines are measured as functions of the distance from the foil. The data is analyzed with a computer program, which yields (in agreement with theory) mean lives of the hydrogen atom excited states involved, and the relative initial state populations of states belonging to the same principal quantum number. There is no indication of cascading.

Es werden vier Erkrankungen aus einer Druckerei beschrieben, in welcher Methylglykol (= Athylenglykolmonomethylather) als Losemittel fur Anilinfarben im Vierfarbendruck verwendet wurde. Die beobachteten Erkrankungssymptome werden mit den bisher bekannt gewordenen gewerblichen Erkrankungen durch Methylglykol verglichen, die in Hemdenfabriken bei der Herstellung von Hemdenkragen unter Anwendung von Hitze entstanden waren.

Ion beams of hydrogen and lithium are accelerated to energies of 50–400 keV and sent through a thin carbon foil. The decay of hydrogen states is observed by recording light intensities as a function of distance behind the foil. Two detectors are used simultaneously to measure Lyman-α and Balmer lines. They consist of an interference filter with cooled multiplier and an MgF 2 filter with channeltron, respectively. A correlated fit of both decay curves allows satisfactory elimination of cascade effects and yields an experimental lifetime for Ly-α of (1.592± ±0.025)ns. The main error results from uncertainties in the beam velocity. The initial state populations obtained using H 2 + and proton beams show significant differences which may be of interest concerning the ion-foil interaction problem. The lithium spectrum is measured between 400 and 1500 A using a 6 Li + beam viewed by a 0.5 m Seya-Namioka VUV monochromator with a channeltron detector. In this range, all known Li II transitions are found and most of them are investigated for lifetimes, cascades, and initial state populations. Also lines in the hydrogen-like Li III spectrum are observed, equivalent to H α through H σ . Their decay curves reveal the existence of a long-lived cascades which is believed to originate from an autoionizing state of Li + .