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The principles of neutron spectrometry for determination of the toroidal rotation velocity (V-t) of the plasma in tokamaks are discussed. Comparison is made with photon spectroscopy which shows that neutron spectroscopy can be used as a rotation diagnostic and that its applicability depends on the availability of high neutron fluxes and the development of methods to measure the neutron energy with very high precision. It is found that neutron spectroscopy could be a feasible rotation diagnostic for burning fusion plasmas to be produced in the next generation tokamaks such as ITER. It is' proposed that V-t should be derived from the difference spectrum obtained from the simultaneous measurement of neutrons emitted tangentially in two opposite directions. The problems connected with the calibration and stability requirements on the neutron spectrometer system for V-t measurements are illustrated and possible technical solutions discussed. (C) 1997 American Institute of Physics.

Phytoextraction may be applied at field scale when the removal of bioavailable metals is the specific target of the technology. Residual metals in soil can be considered substantially inert or to be evaluated by site specific risk analysis.

The status of the ITER tokamak design at the mid-point of the EDA has been described. Relative to the Outline Design, major improvements have been incorporated in the modifications have simplified the design and facilitated fabrication, assemble and maintenance. The divertor concept remains similar to that of the OD, except a vertical target has been adopted as the first option. The cassette approach retains flexibility and permits rapid changeout of the divertor, which will allow ITER to take full advantage of future progress in divertor physics. The projected plasma performance of the IDR design is essentially unchanged from that of the OD, and allows realization of the ITER objectives based on extrapolation of the present confinement behavior. Disruptions produce substantial loads on all in-vessel components and their effects must be carefully taken into account in design of systems which extend into the vessel ports.

Langmuir probes provide a simple measurement of local plasma parameters at the divertor target, information which is difficult to obtain otherwise. In ITER this information is critical for the operation and the control of the divertor in the desired mode.

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Recent theoretical and experimental investigations had promising results concerning the potential of Doppler-free two-photon induced Lyman-α fluorescence (2γLy-α) as a means for selective direct measurements of atomic densities of hydrogen isotopes in magnetically confined fusion plasmas. Even under tokamak conditions, all the two-photon absorption profiles of H, D, and T exhibit sharp, nearly unshifted central components with typical widths fitting well with the bandwidth of pulsed single-mode laser spectrometers which will be able to deliver the required power and quality needed for tokamak diagnostics. A first 2γ Ly-α fluorescence signal was observed at the plasma generator PSI-1 of IPP Berlin with high spatial resolution (o 3mm, 8 mm length) in a pure deuterium plasma beam, o 100 mm, ne ≈ 5·1012 cm-3, Te ≈ 5 eV. We are therefore convinced, that measurements of the nT/nD ratio from 0.1 to 10 will be possible in the edge plasma of ITER, with single shot accuracy better than 20% and with high spatial and temporal resolution at a laser repetition rate of 50 Hz. The detection limit for each isotope is estimated to be 109 cm-3.

The hostile environment, the very restricted access geometry, the required spatial resolution and the target accuracy all impose severe constraints on the design of many techniques proposed for spatially resolving ITER plasma parameters. Despite the constraints it appears feasible using LIDAR Thomson scattering to make measurements of the electron temperature and density profiles in the ITER core plasma. A generic scheme using reflective optics for the front end is adopted. The scheme uses a folded mirror system positioned inside a shielded labyrinth located in a standard radial port. The same mirror surfaces and vacuum window are used for both the laser input and the collection path. Radial and tangential sight lines are considered. The sight line uses a single 30 cm diameter blanket penetration and an exit window of

The effort on generic access for diagnostics to date has addressed the port requirements and types of solutions feasible and required to be incorporated in the conceptual designs of diagnostics. These must be further refined and detailed in each diagnostic area and more importantly incorporated in the design of the other, non-diagnostic ITER systems. The approach shall still be the same, to look at the design of specific diagnostic systems or of the component solution for specific systems and then to broaden the design to include other similar systems. The ITER diagnostic design problems originate from radiation shielding and damage; removal of nuclear heating; increased reliability and safety related to the tritium confinement barriers.

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A new approach for the test mass suspensions of the VIRGO interferometric antenna has been proposed to increase the sensitivity at low frequencies by the reduction of the effects of vertical noises on the test mass. The experimental results are presented and discussed.

A wideband (dc to 500 Hz) low noise accelerometer has been developed. It makes use of a suspended mass whose displacement relative to the supporting structure is sensed by a linear variable differential transformer. It works both in horizontal and in vertical direction. The electronics is connected to the mechanical structure through 12 m long cables. The spectral sensitivity is 7×10−10 (m/s2)/√Hz below 6 Hz. The accelerometer will be used to perform an inertial damping of the resonances of the suspension of the mirrors in VIRGO, an interferometric antenna for gravitational waves detection.

Transport studies in the RTP tokamak are presented. A Z(eff) scan shows a weak dependence of chi(e) on collisionality. Studies of the progagation of heat pulses, induced by both modulated ECRH and sawteeth, show that chi(inc) is independent of input power. Moreover, these perturbative studies indicate a transport barrier related to the q = 1 surface. Independent evidence for the existence of such a transport barrier comes from high-resolution multiposition Thomson Scattering measurements.

The activity of rifabutin against Toxoplasma gondii was investigated in vitro and in vivo. One set of in-vitro studies used either a low virulence or a high virulence T. gondii strain subcultured in drug-free conditions after exposure to various drug concentrations. No parasite growth was observed after subculture at 1 month after exposure to 6 mg/L of rifabutin for the low virulence and 12 mg/L for the high virulence strain. The IC50 of rifabutin was 26.5 mg/L in a different series of experiments using an enzyme-linked immunoassay) and the T. gondii high virulence strain. In similar experiments with clarithromycin, low virulence and high virulence parasites grew in drug-free subcultures following exposure to drug concentrations as high as 100 mg/L; the IC50 of clarithromycin exceeded 100 mg/L for the high virulence strain. In the acute toxoplasmosis murine model, mice received a 12 day treatment starting 5 days before infection with high virulence parasites. Survival was significantly improved compared with untreated controls in response to 50, 100 and 200 mg/kg/day rifabutin and 100 and 200 (but not 50) mg/kg/day clarithromycin, and with the combination of the two drugs at 25, 50 and 100 mg/kg/day. Survival was significantly improved when combination therapy was administered. The calculated ED50 values (mg/kg/day) were 160.5 for rifabutin, 119.4 for clarithromycin, and 114.8 for the combination. In the present experimental conditions rifabutin proved effective in vitro and in vivo against T. gondii and showed potentiation with clarithromycin in vivo.

In this matched-pair study 139 pregnant women were matched on the basis of age to an equal number of non-pregnant women with no signs of genital infection. The mean age was 28.7 years (range 20-41). The cut-offs used for detection of chlamydial antibody were 1:64 and 1:128 for IgG and 1:16 for IgA. IgG antibody at 64 was detected in 37.4% of pregnant women, compared to 46% of controls (p = 0.145). There was, however, a statistically significant difference between the groups for IgG at 128 (gravidae = 15.8%; controls = 28%; p = 0.014). IgA were detected in 8.6% and 16.5% of subjects, respectively (p = 0.047). IgG levels did not vary with increasing age among the pregnant women, but rose significantly with age in non-pregnant controls (logistic regression p-values = 0.011 and 0.006, for IgG at 64 and 128, respectively). IgG-positive women in the control group tended to be older than pregnant IgG-positive women (p = 0.06). These differences could not be explained by marital status, parity or use of oral contraceptives. In view of the lack of epidemiological differences, biological explanations might be invoked.

A progress report is presented on the development of the anticyclotron — deceleration of antiprotons and negative muons via collisions in a low-pressure gas or thin foils during revolutions in a cyclotron field. Beam tests performed at CERN and PSI are reported and future plans for applications outlined.

Toxoplasma gondii parasites were isolated in vitro and in vivo from a hare that had died of disseminated toxoplasmosis. Intraperitoneal inoculation of either homogenate of hare organs or parasites isolated on culture produced chronic infection in mice. However, a progressive increase of virulence following subsequent mouse-to-mouse transfections was observed. These findings suggest that host-parasite interaction plays a major role in determining the degree of pathogenicity, and that in vitro and in vivo isolation, if not followed by subsequent passages, may fail to reveal major differences in virulence between isolates.

Summary The euploid-diploid cell line CE, issuing spontaneously from a normal human bone marrow culture, displays B-cell differentiation and activation markers and is positive (⩾ 90 % of cells) for Epstein-Barr nuclear antigens. CE suspensions were inoculated with serum from a patient chronically infected with hepatitis C virus (HCV). After inoculation, the cells were regularly subcultured with a split ratio of 1:2 every 4–6 days. RNA extracted as late as 65 days after infection from the inoculated cells were positive by polymerase chain reaction for the 5′ untranslated region of the HCV genome, and viral antigens were detected by immunofluorescence. Virus was also released from the infected cells into the medium. Intracellular HCV could be successfully passaged twice in CE cultures. On the basis of these findings, the CE cell line appears promising as a model for studying HCV replication and persistent infection in vitro.

We describe a computer controlled beam diagnostic system, which is capable to collect data for plotting three-dimensional current density map in beam profile mode and emittance maps in x, x’ or y, y’ emittance mode. Further beam parameters can be deduced by taking the advantages of the software. The versatility of the system is demonstrated on measurements of beams produced by a DC mode hollow cathode ion source and by a burst mode duoplasmatron.

The excitation profiles of several Raman bands of trans-azobenzene solution in carbon tetrachloride were measured in resonance with the first allowed electronic transition peaked around 320 nm. The experimental results were analysed by means of a multi-mode Franck–Condon model to obtain some excited state molecular parameters; such parameters were found to reproduce well the red side of the absorption band whereas some inconsistencies between experiment and calculation persist on the UV side. This has been tentatively explained as due to the contribution of a higher energy electronic state whose absorption band is peaked around 287 nm and which may slightly affect the parameters obtained.

The incremental electron heat diffusivity chi(inc) is determined in Rijnhuizen Tokamak Project plasmas by measurements of simultaneous heat pulses due to (1) the sawtooth instability and (2) modulated electron cyclotron heating. No systematic difference is observed between the two measured chi(inc) values, which are both significantly larger (chi(inc)/chi(e)PB = 2-4) than the diffusivity obtained from power balance analysis, chi(e)PB.

Equilibrium pool scintigraphy was performed in 11 obese subjects (BMI 34 +/- 2) and in 14 normal control subjects. Temporal and spatial smoothing of the data was then performed followed by time-activity curve generation using a semiautomatic second derivative edge-detection algorithm. The increase in counts during the first third of diastole divided by the total change in number of counts during diastole was determined as the one-third filling fraction. This index of diastolic filling was significantly decreased in obese subjects as compared to the control group. These findings indicate that diastolic abnormalities may be an early finding in obesity-linked heart disease, occurring in the presence of normal systolic function (E.F. = 65 +/- 5%).

One hundred and one women suffering from "sine causa" recurrent abortion were screened for Chlamydia trachomatis (C.T.) infection by using direct examination, cultural and serological procedures. In this series, C.T. infection did not appear to be related to increased risk of recurrent abortion. The culture-positive and serology-positive rates (14.85% and 34.65%, respectively) did not differ from other unselected populations. Neither time from last abortion nor type of abortion were significantly related to C.T. infection. Nonetheless, the women who underwent examination within one year from last abortion and had a culture-positive partner as well, were more likely to present with a C.T.-positive culture.

In recent years Chlamydia trachomatis has emerged as a significant cause of acute salpingitis and reproductory failure. In this study, 85 women suffering from primary infertility and 85 parous women as control group were screened for C. trachomatis genital infection by means of cell culture and antigen detection on genital samples as well as the detection of anti-chlamydial antibodies in blood. C. trachomatis was detected in 31.8% of infertile women and 5.8% of fertile subjects. Isolation of C. trachomatis in cell culture proved to be the most reliable diagnostic tool when compared to immunofluorescence staining on smears and serology. Although the latter may be considered of great value in epidemiological researches, culture isolation should be associated for the diagnosis of active infection.

A polyclonal rabbit antibody raised against an Fc receptor (FcR)-like membrane glycoprotein fraction of chronic leukaemic lymphocytes has previously been prepared and partially characterized. This antibody, called AbA, was found to precipitate a 70-kDa and a 45-kDa fraction of the detergent lysate of U937 cells and to inhibit ligand binding to Fc gamma R on the P388D1 murine macrophage cell line. In the present work we have characterised this antibody further. All Fc gamma RII-positive B lymphoblastoid cell lines, as well as resting human B lymphocytes, were positively stained with the AbA antibody. U937 cells were found to be negative, but after stimulation with phorbol ester (PMA), 50% of the cells became positive. AbA antibody did not react with human T cell lines or with the T + 0 cell subset of peripheral blood. Monocytes were also negative. On the other hand, AbA antibody exhibited a dose-dependent inhibition of antibody-mediated cytotoxic reaction (ADCC) of monocytes, while not affecting K cell-mediated ADCC. It had an inhibitory effect of EA rosette formation of B cells and stimulated U937 cells. Furthermore, it interacted with the soluble form of Fc gamma RII released by activated B lymphocytes, and--similarly to IgG--precipitated a 33 kDa fraction from the supernatant of B cells.

Resonant Raman spectra of highly oriented trans polyacetylene have been obtained for different scattering configurations at various exciting wavelengths. The polarization properties of the Raman active phonons have been determined for the first time. The changes in the Raman bandshapes observed upon changing the scattering configuration seem to imply that the dispersion of the Raman bands originates from a distribution of conjugation lengths.

Dur ing a work on co-operat ive cascade effects following the one-photon exc i ta t ion to the 7P:, level in cesium, CAMPANI Ct al. (~) de tec ted a co-opera t ive emission in the t ransi t ion 6P~ ~ 6S 89 to the ground state. Such an effect m a y be explained w i t h a model equ iva len t to the one used by 0KADA et al. (2) to t r ea t a s imilar cascade in l i t h ium vapours . This model (3) assumes the co-opera t ive emissions in the cascade to be resonant wi th the t rans i t ions 7 P i ~ 7S~ (21 : 3.09 9m), 7S~ ~ 6P.~ (~2 ~ 1.47 9m) and 6P t--~ 6S 89 (~ = 0.852 ~m) (see fig. 1). To fur ther check this assumpt ion and to exclude possible s t imula ted electronic Raman sca t te r ing (SERS) which are no t resonant , we used the co-operat ive emission from 6P~-~ 6S~ t rans i t ion to pump cesium vapour and measure the rad ia t ive l i fe t ime of the 6P~ exc i ted level by means of t ime-resolved spectroscopy technique. Such a direct technique, to our knowledge, has never been used before for this exci ted level (see table I). F igure 2 shows a schemat ic d iag ram of the exper imenta l appara tus . A Molectron DL200 dye laser p u m p e d by a N 2 laser (laser E le t t ron ica A500) b y means of a 10 -2 molar solution of 7D4 MC iu e thanol de l ivered l ight pulses at 2 ~ 459.4 nm. These pulses were about 4 nS F W H ~ [ long, wi th an average energy of 20 fzJ and a spectral bandwid th of 15 GIIz. We did not use an i n t r a c a v i t y F a b r y P e r o t etalon to reduce bandwidth, since wc were not in teres ted in resolving hyperf ine s t ructure . A laser beam wi th

The Cs 8S level hfs splitting δ 8 has been measured. The experimental value δ 8 = (900 ± 60) MHz is in good agreement with both other experimental results and theoretical predictions.

Sublethally irradiated mice primed with dinitrophenyl (Dnp)-keyhole limpet hemocyanin immediately after irradiation or 30 days later and subsequently boosted with a second injection of antigen displayed a secondary response to Dnp characterized by antibody affinity greater than that in unirradiated controls. Also, in radiation chimeras primed with Dnp-keyhole limpet hemocyanin 120 days after syngeneic or allogeneic bone marrow transplantation the antibodies against Dnp produced after boosting were of higher affinity than the antibodies raised in normal mice. These findings are tentatively attributed to lack of suppressor thymus-derived lymphocytes (T cells) in sublethally irradiated mice and bone marrow chimeras, in which the enhanced ability to produce antibodies of high affinity may compensate for quantitative defects of the immune system.

Novel data on the polarization properties of the two resonantly enhanced Raman bands of trans polyacetylene have been obtained using the 609.6 nm line of a dye laser. Approximate corrections to take into account the optical anisotropy of the sample have been worked out. The changes of the observed band shapes and of the corrected intensities with the scattering configuration are consistent with a distribution of conjugation lengths. For short conjugated segments the electronic transition moment does not appear to be strictly aligned along the chain direction.

The results of a measurement of the 2S1/2-2P3/2 energy difference in the (μ4He) muonic system are presented. Full account of the experimental method as well as an up-to-date review of the pertaining theoretical predictions are given. The obtained results show a good agreement with QED predictions; the electronic vacuum polarization term of order α is checked with a relative accuracy of 5·10−3.

We report the results of an experimental investigation on the properties of the (μ 4He) 2S + metastable muonic system, which was performed stopping negative muons in a pure helium target at pressures ranging from 10 to 50 atm, and observing the total yield and the differential time distribution of the X-rays released in delayed coincidence with the arrival of muons. At each pressureP, information was obtained on the following quantities:a) the total disappearance rate λ2S,tot(P) of the (μ 4He) 2S + system,b) the disappearance rates λA(P) and λSt(itP) of the (μ 4He) 2S + system for external Auger effect and Stark-mixing collisions,c) the fractione 2S of muons stopped in helium which form the (μ 4He) 2S + system. The results obtained on λ2S,tot(P) are in agreement with the results of a cascade calculation, which was performed requiring consistency with previous experimental results; the present measurements show that the variation ofe 2S (P) with pressure in the range (7÷50) atm is small. Good agreement was found between the values for the two-quantum decay rate λ2X of the (μ 4He) 2S + system derived from the present data and the theoretical predictions. The results obtained on λ2S,tot(P), instead, are somewhat in conflict with the results of a recent calculation on λ2St(P). The possible reasons of such disagreement are discussed, referring to possible clustering effects of the helium atoms around the (μHe+ ion.

We have developed a manufacturing process for arrays of high resistance lead glass tubing of various diameters, ranging from 500 μm to several mm, for the detection of γ-rays. We describe the applications of this type of device to positron emission tomography and high energy physics.

Results of an experiment to measure the 2P 3/2 −2S 1/2 energy difference δ 1 in the muonic (μ −4 H e) + ion are presented; we found δ 1 exp = 1.5274 ± 0.0009 eV. Comparison with QED predictions shows that there is agreement between theory and experiment within 0.0087 eV; this limitation is mainly due to the uncertainty with which the r.m.s. charge radius of the 4 He nucleus is known.

Raman excitation profiles for the chromate 863 cm−1 totally symmetric mode and for its first two overtones, measured in rigorous resonance with the absorption band at 372 nm, are reported. Data were taken on a lyophilised mixture of K2CrO4 in K2SO4, and the 981 cm−1 sulphate fundamental was used as an internal standard for intensity measurements. Results are analysed in terms of a model based on the Franck-Condon scattering mechanism assuming either a singlet F2 resonant state or three non-degenerate states resulting from the Cs symmetry of the CrO2−4 ion in our medium. Comparisons are made with the results obtained by other authors for the isoelectronic MnO−4 ion.

An apparatus is described in which a ruby-pumped dye laser is used to induce transitions from the 2S to the 2P levels of the muonic ion (μHe)+. The dye laser supplies infra-red radiation pulses in the wavelengths (8040÷8180) A, at typical repetition rates of 1 pulse every 4 s, with an energy release per pulse of 300 mJ for 1.2 J pumping

Describes a Raman spectrometer employing a pulsed dye laser and a 'gated analogue detection' system covering the visible and near-UV region (down to 360 nm) without the use of frequency doubling. The S/N performance of this apparatus is discussed and some 'test' experimental results are presented. The apparatus is to be preferred to those employing conventional CW lasers when efficient background rejection or low average power is required. Moreover, it is to be preferred to those employing the 'gated photon counting' technique because of a higher S/N ratio capability.

A drift collection calorimeter prototype of 11.2 N/sub 0/ radiation lengths (42 cm actual), which has a combined radiator and electric-field shaping structure made of high-density lead glass tubing, is presented. Extensive experimental measurements at the CERN-PS test beam are reported. A linear energy response has been found in the energy range from 2 to 5 GeV, with an energy resolution of (18+or-2)%/ square root E. >

The results of a new measurement of the 2 S 1 2 -2 P 3 2 splitting S 1 in the muonic ion (μ −4 He) + are presented. We found S e xp 1 = 1527.5 ± 0.3 meV. Using the new, recently determined, value of the rms charge radius for 4 He we obtain for the difference D , between S exp 1 and the corresponding theoretical prediction, the value D = 0.2 ± 4.2 meV: this value directly confirms, assuming μ-e universality, the QED vacuum polarization prediction to 0.25 %.

Pionic X-rays have been observed when negative pions are stopped in a hydrogen gas target. The intensity of the K lines has been found to be about 0.12 X-ray/pion stopped; moreover we found K α /K = 0.53 ± 0.04.