A 2-4 keV multilayer mirrored channel for the NIF Dante system.

During inertial confinement fusion experiments at the National Ignition Facility (NIF), a capsule filled with deuterium and tritium (DT) gas, surrounded by a DT ice layer and a high-density carbon ablator, is driven to the temperature and densities required to initiate fusion. In the indirect method, 2 MJ of NIF laser light heats the inside of a gold hohlraum to a radiation temperature of 300 eV; thermal x rays from the hohlraum interior couple to the capsule and create a central hotspot at tens of millions degrees Kelvin and a density of 100-200 g/cm3. During the laser interaction with the gold wall, m-band x rays are produced at ∼2.5 keV; these can penetrate into the capsule and preheat the ablator and DT fuel. Preheat can impact instability growth rates in the ablation front and at the fuel-ablator interface. Monitoring the hohlraum x-ray spectrum throughout the implosion is, therefore, critical; for this purpose, a Multilayer Mirror (MLM) with flat response in the 2-4 keV range has been installed in the NIF 37° Dante calorimeter. Precision engineering and x-ray calibration of components mean the channel will report 2-4 keV spectral power with an uncertainty of ±8.7%.

Time-resolved near backscatter imaging system on Laser MegaJoule.

The newly operating near-backscattering imaging (NBI) system on the Laser MegaJoule (LMJ) is briefly described with emphasis on the temporally resolved measurements and their synchronization with the LMJ laser pulse through target shots taken as part of the diagnostic commissioning campaign. The NBI measures the stimulated Brillouin and Raman scattered light around two quadruplets (one inner and one outer) of the upper LMJ hemisphere. The temporal resolution is achieved with a unique system: a specifically designed wide-open optical lens images 40 points of a diffuser onto an array of optical fibers with the scattered light recorded on a multiplexed photodiode array.

First set of gated x-ray imaging diagnostics for the Laser Megajoule facility.

The Laser Megajoule (LMJ) facility located at CEA/CESTA started to operate in the early 2014 with two quadruplets (20 kJ at 351 nm) focused on target for the first experimental campaign. We present here the first set of gated x-ray imaging (GXI) diagnostics implemented on LMJ since mid-2014. This set consists of two imaging diagnostics with spatial, temporal, and broadband spectral resolution. These diagnostics will give basic measurements, during the entire life of the facility, such as position, structure, and balance of beams, but they will also be used to characterize gas filled target implosion symmetry and timing, to study x-ray radiography and hydrodynamic instabilities. The design requires a vulnerability approach, because components will operate in a harsh environment induced by neutron fluxes, gamma rays, debris, and shrapnel. Grazing incidence x-ray microscopes are fielded as far as possible away from the target to minimize potential damage and signal noise due to these sources. These imaging diagnostics incorporate microscopes with large source-to-optic distance and large size gated microchannel plate detectors. Microscopes include optics with grazing incidence mirrors, pinholes, and refractive lenses. Spatial, temporal, and spectral performances have been measured on x-ray tubes and UV lasers at CEA-DIF and at Physikalisch-Technische Bundesanstalt BESSY II synchrotron prior to be set on LMJ. GXI-1 and GXI-2 designs, metrology, and first experiments on LMJ are presented here.

Laser smoothing and imprint reduction with a foam layer in the multikilojoule regime.

This Letter presents first experimental results of the laser imprint reduction in fusion scale plasmas using a low-density foam layer. The experiments were conducted on the LIL facility at the energy level of 12 kJ with millimeter-size plasmas, reproducing the conditions of the initial interaction phase in the direct-drive scheme. The results include the generation of a supersonic ionization wave in the foam and the reduction of the initial laser fluctuations after propagation through 500 mum of foam with limited levels of stimulated Brillouin and Raman scattering. The smoothing mechanisms are analyzed and explained.

Characterization of laser-irradiated YNi 2 B 2 C surfaces by Auger electron spectroscopy.

The suitability of laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) for precise analysis of YNi(2)B(2)C has been investigated. The intensity ratios B/Y and Ni/Y were found to vary during ablation as a function of the ablation conditions. This could be because of fractionation, owing to incongruent ablation or transport and plasma effects. The bottoms and surroundings of the craters were investigated by scanning Auger electron spectrometry. The bottoms of the craters produced by ablation are covered with a thin oxide comparable with that on the polished crystal surface. The craters are surrounded by an oxide layer the dimensions and thickness of which depend on the laser conditions. The formation of this oxide can be assumed to be a result of partial oxidation of sample material during the ablation process; the oxide is then redeposited around the laser crater.

Development and validation of a new bitumen fume generation system which generates polycyclic aromatic hydrocarbon concentrations proportional to fume concentrations.

Bitumen fumes emitted during road paving and roofing contain polycyclic aromatic compounds (PACs) of potential health concern. Little information is available for an experimental device devoted to inhalation experiments with animals exposed to bitumen fumes, and in all studies the systems were never validated for a range of fume concentrations, which prohibited their use for toxicological concentration-effect studies. Therefore, the purpose of this study was to validate a new experimental device able to generate bitumen fumes at different total particulate matter (TPM) concentrations with a linear correlation between TPM and the concentrations of different PACs, thus allowing toxicological dose-response studies with fumes representative of those in the field. Atmosphere samples collected from an animal exposure chamber allowed the determination of TPM, toluene soluble matter, polycyclic aromatic hydrocarbons (PAHs) and semi-volatiles. The particulate size distributions were determined in order to assess the deposition pattern in the respiratory tract. The temperature of 170 degrees C was chosen by analogy with the upper range of the temperature used during paving operations. The temperature of the air passing over the fume emission area was regulated to 20 degrees C and stirring of the heated bitumen was restricted to 90 r.p.m. The data show that the objective of developing a static fume generation system that reproducibly produces fumes in the inhalation chamber for specified target concentrations (TPM) were successful. The within-day variation coefficients for TPM were between 2.5 and 6.1%. The day-to-day variations for TPM concentration were between 4.1 and 5.8%. The concentrations of the 4-5 ring PAHs and the polycyclic aromatic sulphur heterocycles were proportional to the TPM concentration. The 2 and 3 ring PAH concentrations showed a deviation from proportionality with the TPM, probably due to their re-evaporation during sampling. The mass median aerodynamic diameter of airborne particles varied from 1.4 micro m at a fume concentration of 5 mg/m(3) to 3.2 micro m at 100 mg/m(3). In conclusion, this equipment was suitable for nose-only inhalation studies in the 5-100 mg/m(3) range of TPM. Bitumen fumes were generated with a good reproducibility under well-controlled conditions. Finally, the PAH profiles from atmospheric samples were in good agreement with those measured during road paving.

Differential RNA expression of alpha-expansin gene family members in the parasitic angiosperm Triphysaria versicolor (Scrophulariaceae).

Haustoria are parasitic plant specific organs that locate, attach to, and invade host plant tissues. Parasitic species of the Scrophulariaceae develop haustoria on their roots in response to chemical signals released by host plant roots. Haustorium development was induced in vitro in roots of the parasitic Scrophulariaceae Triphysaria versicolor by treating them with exudates obtained from maize roots, the chemical 2,6-dimethoxybenzoquinone (DMBQ) or the cytokinin 6-benzylaminopurine (BAP). Morphological responses of T. versicolor roots to these haustoria inducing factors (HIFs) included localized swelling and epidermal hair proliferation near the root tips. These responses were not observed when roots of the non-parasitic Scrophulariaceae Lindenbergia muraria were similarly treated. Because expansin proteins are closely associated with plant cell wall expansion and growth, we examined the expression of expansin genes in response to HIFs. We isolated cDNAs homologous to transcripts encoding three distinct alpha-expansin proteins in T. versicolor. Northern-blot analyses indicated that these transcripts were differentially abundant in different tissues. Steady-state levels of two expansin transcripts increased in T. versicolor roots exposed to BAP, but not DMBQ or maize root exudates. Expansin transcript abundance also increased in L. muraria in response to BAP treatment. These results suggest that the expansins examined fulfill functions distinct from haustorium development.

Quinone oxidoreductase message levels are differentially regulated in parasitic and non-parasitic plants exposed to allelopathic quinones.

Allelopathic chemicals released by plants into the rhizosphere have effects on neighboring plants ranging from phytoxicity to inducing organogenesis. The allelopathic activity of naturally occurring quinones and phenols is primarily a function of reactive radicals generated during redox cycling between quinone and hydroquinone states. We isolated cDNAs encoding two distinct quinone oxidoreductases from roots of the parasitic plant Triphysaria treated with the allelopathic quinone 2,6-dimethoxybenzoquinone (DMBQ). TvQR1 is a member of the zeta-crystallin quinone oxidoreductase family that catalyzes one-electron quinone reductions, generating free radical semiquinones. TvQR2 belongs to a family of detoxifying quinone oxidoreductases that catalyze bivalent redox reactions which avoid the radical intermediate. TvQR1 and TvQR2 message levels are rapidly upregulated in Triphysaria roots as a primary response to treatment with various allelopathic quinones. Inhibition of quinone oxidoreductase enzymatic activity with dicumarol prior to quinone treatment resulted in increased transcript levels. While TvQR2 homologs were upregulated by DMBQ in roots of all plants examined, TvQR1 homologs were upregulated only in roots of parasitic plants. Phylogenetic trees constructed of TvQR1 and TvQR2 protein homologs in Archea, Eubacteria and Eukaryotes indicated that both gene families are ancient, yet the families have dissimilar evolutionary histories in angiosperms. We hypothesize that TvQR2-like proteins function to detoxify allelopathic quinones in the rhizosphere, while TvQR1 has specific functions associated with haustorium development in parasitic plants.

Study of fifteen respirable aerosol samplers used in occupational hygiene.

European and international standards lay down criteria for the size-selective aerosol sampling in occupational hygiene. Aerosol samplers are supposed to match these target sampling criteria. This study focused on 15 aerosol samplers used to sample the conventional respirable fraction. An aerodynamic particle sizer (APS) method was used to measure the sampling efficiency of the samplers in a low-velocity wind tunnel. Polydisperse coal dust was generated as the test aerosol. The data were fitted by an appropriate mathematical model. For some instruments the results show serious deviations from the conventional target curve, whereas other devices meet the convention quite well. The flow rate of certain cyclone-separator-based instruments was optimized to adjust their sampling efficiency. The mass concentration bias and accuracy of the samplers were calculated for a number of ranges of particle size distributions of aerosols commonly found in industrial workplaces. Finally, the performance of each sampler was evaluated using bias and accuracy maps. Most of these samplers are suitable for sampling the CEN-ISO-ACGIH respirable fraction of aerosols, but several require modification of the flow rate. For real industrial situations, the rough knowledge of the aerosol size distribution can guide the choice of an appropriate sampling technique.

Computerized equipment for the delivery of inhaled doses of solid particles in specific bronchial challenge.

An apparatus to generate solid particles was tested for use in diagnosing occupational asthma. This equipment measures the inhaled dose of dry particles during specific inhalation challenge. It includes an aerosol generator, a cyclone type particle size selector, and an inhalation chamber to which a patient breathing at tidal volume can be connected for the test. It is fully controlled by a standard personal computer in automatic mode, acting on the flow rate and the aerosol generator to maintain the concentration at a fixed value, usually 3 mg/m3. The dose of aerosol delivered to the patient was calculated from the aerosol concentration, and the inhaled volume was calculated by integration of the corresponding signals. The coefficient of variation for this measurement was estimated to be 12%. The mass median aerodynamic diameter (MMAD) of aerosol inside the inhalation chamber was measured for three substances: lactose, wheat flour, and buckwheat flour. The MMAD of the aerosol inside the chamber was also estimated from the particle size distribution of the raw powder. The relative difference between the measured MMAD and the calculated value was less than 15%. The corresponding relative difference between the measured geometrical SD and the calculated value was found to be less than 26%.

Host-root exudates increase gene expression of asparagine synthetase in the roots of a hemiparasitic plant Triphysaria versicolor (Scrophulariaceae).

Triphysaria is a facultative root parasite in the Scrophulariaceae family. Similar to other related parasites, the development of the parasitic life cycle is initiated by molecular signals released from appropriate host roots. Using a differential display, we isolated cDNAs preferentially abundant in T. versicolor roots exposed to Trifolium repens (white clover) root exudates in vitro. Sequence analysis indicated that one of the differentially expressed cDNAs had significant homology to the nitrogen-assimilating enzyme, asparagine synthetase (AS). T. versicolor AS cDNA clones were isolated and placed into three distinct classes on the basis of nucleotide sequence variations. All three classes encoded identical AS proteins. AS was expressed in both roots and shoots of in-vitro-cultured T. versicolor. Steady-state levels of AS mRNA increased in T. versicolor roots several-fold when seedlings were exposed to exudate obtained from hydroponically grown Arabidopsis thaliana roots. Therefore, AS transcript levels increased in response to exudates from two different hosts (Trifolium and Arabidopsis). The T. versicolor AS message levels increased to a similar magnitude when seedlings were incubated in the dark. Interestingly, AS levels were unaffected by treatment with the Striga haustoria inducer 2,6-dimethoxybenzoquinone. The potential role of AS in root parasitism is discussed.

Personal thoracic CIP10-T sampler and its static version CATHIA-T.

A specific version of the personal aerosol sampler CIP 10 was designed, named CIP10-T, for sampling the conventional CEN thoracic fraction. A static sampler, named CATHIA, was also designed. It uses the same sampling head, but the size selected particles are collected onto a filter. The combined particle efficiency of the aspiration slot and the selector was measured in a horizontal wind tunnel at low air velocity, close to 16 cm s-1. The flow rate of both samplers was fixed at its nominal value, i.e., 71 min-1. Two different methods were used: the former was based on the Aerodynamic Particle Sizer (TSI); the latter used the measurement of particle size distribution of the collected samples by the Coulter technique. For the CIP10-T sampler, the particle collection efficiency onto the rotating cup was also measured. For both samplers bias and accuracy maps have been calculated, following the recommendations of a new CEN standard about sampler performance. The bias does not exceed 10% in absolute value for both samplers, within a large range of particle size distribution of the total aerosol. For the CIP10-T sampler, the accuracy map exhibits a large area where the accuracy is better than 10%, corresponding for example to 4 microns < or = MMAD < or = 14 microns for GSD = 2. For the same geometric standard deviation, the accuracy is still better than 20% for 15 microns < or = MMAD < or = 21 microns. For the CATHIA-T sampler, the accuracy map can be roughly divided into two parts. The accuracy remains better than 10% for MMAD < or = 12 microns, and it remains between 10 and 20% for coarser aerosols, with 13 microns < or = MMAD < or = 20 microns, provided GSD > or = 2.

Comparative analysis of BiP gene expression in maize endosperm.

Binding protein (BiP) is the endoplasmic reticulum member of the highly conserved HSP70 (heat shock protein 70) family of molecular chaperones. We have isolated and characterized two different BiP cDNA clones corresponding to genes expressed in immature kernels. These two cDNAs share extensive sequence similarity but map to unlinked loci in the maize genome. A comparison of the aa sequences predicted from the cDNA clones revealed only six aa differences between them. Investigation of gene-specific expression was carried out by RNA gel blot analysis. RNAs corresponding to both cDNA clones were present in increased amounts in the endosperm of floury-2 (fl2), Mucronate (Mc) and Defective endosperm-B30 (De*-B30) maize mutants, which produce abnormal storage proteins. Similar increases in RNAs corresponding to both probes were detected in cells treated with either of two agents that interfere with protein folding, azetidine-2-carboxylic acid (AZC) and tunicamycin. Investigation of the genomic complexity of the BiP genes by Southern blot analysis revealed several cross-hybridizing bands. These results are suggestive that the BiP genes expressed in endosperm are coordinately regulated members of a more complex maize BiP multigene family.

[Changes in coagulation physiology and rheology after preoperative normovolemic hemodilution]. / Gerinnungsphysiologische und rheologische Veränderungen nach präoperativer normovolämischer Hämodilution.

AIM: In a prospective randomised controlled trial the effect of preoperative normovolaemic haemodilution on coagulation, plasma viscosity and plasma protein levels was examined. METHOD: 50 patients undergoing gastrectomies were investigated (haemodilution group, n = 30; control group, n = 20). In the haemodilution group a haematocrit of 30% was aimed at. Blood was replaced by normovolaemic infusion of 6% hydroxyethyl starch 200/0.5. MAIN RESULTS: Haematocrit, colloid osmotic pressure, total serum protein, serum albumin and platelet count were significantly decreased intra- and postoperatively in the haemodilution group compared with control group (p < 0.01). All of these showed no differences between the two groups on the 7th postoperative day. Global coagulation parameters showed dilutional influences without significant differences between the two groups. Measurements of rheological parameters showed a statistically significant decrease in plasma viscosity in the haemodilution group compared with control group (p < 0.01). Haemodilution led to a marked reduction in the use of homologous blood (1 unit/haemodilution group; 10 units/ control group). The average volume of 6% hydroxyethyl starch 200/0.5 administered per patient was 15.2 ml/kgKM/d (7.6-22.2 ml/kgKM/d) in the haemodilution group and 12.7 ml/ kgKM/d (8.4-17.7 ml/kgKM/d) in the control group. CONCLUSION: Haemodilution induced decreases in plasma coagulation, platelet count and plasma proteins did not cause any functional impairement and may just reflect dilution of these parameters. It seems that infusion of 6% hydroxyethyl starch 200/0.5 in an amount of 10-20 ml/kgKM/d does not result in a relevant decrease in coagulation parameters.

Appearance of Endoproteolytic Enzymes during the Germination of Barley.

Barley endoproteolytic enzymes are important to germination because they hydrolyze endosperm storage proteins to provide precursors for new protein synthesis. We recently developed an electrophoretic method utilizing gel-incorporated protein substrates to study the endoproteinases of 4-d-germinated barley (Hordeum vulgare L. cv Morex) grain. This work extends those findings to determine the temporal pattern of the appearance of the endoproteinases during germination, the sensitivities of the proteinases to class-specific proteinase inhibitors, and where, in germinating caryopses, the proteinases reside. Six endoproteinase activity bands (representing a minimum of seven enzymes) were present in 5-d-germinated barley grain extracts subjected to electrophoresis in nondenaturing gels at pH 8.8. The activities of two of the enzyme bands ("neutral" proteinases) increased as the pH was increased from 3.8 to 6.5. The activities of the remaining four ("acidic") bands diminished abruptly as the pH increased above 4.7. Two proteinase bands hydrolyzed gelatin but not edestin, four of the proteinases hydrolyzed both gelatin and edestin at nearly the same rates, and one enzyme degraded only edestin. One neutral endoproteinase was sensitive to diisopropyl fluorophosphate inhibition, and the other was not inhibited by any of inhibitors tested. Four of acidic enzymes were cysteine proteinases [inhibited by trans-epoxysuccinyl-l-leucylamido(4-guanidino)butane and N-ethylmaleimide]; the other was an aspartic acid endoproteinase (sensitive to pepstatin). Only the aspartic proteinase was detected in either ungerminated or steeped barley grain. During the germination (malting) process, the aspartic endoproteinase activity decreased until the second day of germination and then increased until germination day 5. The first endoproteinase(s) induced during germination was a neutral enzyme that showed activity on the 1st day of the germination phase after steeping. Most of the endoproteinases became active on the 2nd or 3rd germination day, but one cysteine proteinase was not detected until the 5th day. Acid cysteine proteinases were present in the aleurone, scutellum, and endosperm tissues but not in shoots and roots. The aleurone layer and endosperm contained almost exclusively band B1 neutral proteinases, whereas the scutellum, shoots, and roots contained both B1 and B2 bands. This work shows that germinating barley contains a complex set of proteinases whose expression is temporally and spatially controlled. But, at the same time, it also shows that this electrophoretic method for separating and studying individual enzymes of this complex will allow us to more readily characterize and purify them.

Loss of transfer RNA genes from the plastid 16S-23S ribosomal RNA gene spacer in a parasitic plant.

The plastid 16S-23S intergenic spacer region in Conopholis americana, a totally heterotrophic angiosperm in the family Orobanchaceae, has undergone large deletions, including the entire tRNA(Ile) gene and all but small remnants of the tRNA(Ala) gene. The length of the region is less than 20% of that of other land plants which have been investigated, making it the smallest 16S-23S intergenic spacer reported thus far for any land plant. The remaining sequences in the spacer are 90.1% identical to tobacco, indicating that, while the region is well conserved at the sequence level, it is evolving rapidly by deletion. Experiments using the polymerase chain reaction and hybridization to DNA gel blots have failed to reveal either of the two missing tRNA genes elsewhere in the Conopholis cell.

Sonography in the diagnosis and therapy monitoring of lymphomas.

Multiple ultrasonographic (USG) evaluations of abdomen were performed in 97 patients: 30 with Hodgkin's disease (HD), 60 with non-Hodgkin lymphomas (NHL) and 7 with primary gastric lymphoma (PGL) before or during chemo- or X-ray therapy. In 33% of HD patients USG was normal, while in 63% splenomegaly, in 40% hepatomegaly and in 20% lymph node enlargement were observed. After therapy, in 57% USG was improved and in only 3% of patients worsening was observed. In NHL patients splenomegaly was observed in 70%, hepatomegaly in 60% and lymph node enlargement in 35%. During follow-up, in 49% of patients improvement and in 3% worsening was observed. In 5 patients with PGL no changes were observed, in further 2 patients in Stage IV stomach wall and infiltration of nearest lymph nodes was observed. USG evaluation of abdomen may be useful in staging and therapy monitoring of malignant lymphomas.

An aberrant plastid ribosomal RNA gene cluster in the root parasite Conopholis americana.

The plastid ribisomal RNA (rRNA) operon of the achlorophyllous root parasite Conopholis americana was completely sequenced. Full-length rRNA genes are retained in the gene cluster, but significant divergence has occurred in the 16S, 23S and 5S genes. Both the 16S-23S intergenic spacer and the 4.5S-5S intergenic spacer have suffered substantial deletions, including the two tRNA genes typically found in prokaryotic and plastid 16S-23S spacers.

A divergent plastid genome in Conopholis americana, an achlorophyllous parasitic plant.

We have used heterologous probes to investigate the degree of sequence conservation in the plastid genome of Conopholis americana, a totally achlorophyllous angiosperm which exists as a root parasite on red oaks. Although Conopholis is completely nonphotosynthetic, it retains a plastid genome in which certain regions, including that which contains the ribosomal RNA genes, are highly conserved. Other regions, including those containing the genes for numerous photosynthesis proteins, are either absent or highly divergent. We also find that the 16S and 23S ribosomal genes of the Conopholis plastid are transcribed and processed, implying a potentially functional genetic apparatus. These results are in agreement with findings reported recently for a related root parasite, Epifagus virginiana (dePamphilis and Palmer, 1990). Furthermore, the plastid genome is maintained in high copy number in fruit tissue, whereas mature seeds have an approximately 10-fold lower copy number.

Competitive protein-binding radioassay of thiamine in simple solutions and in multivitamin pharmaceuticals.

A competitive inhibition radioassay of thiamine is described using a gel obtained by coupling a buckwheat-seed thiamine-binding protein to CNBr-activated Sepharose. The sample to be analysed is incubated with gel suspension and [14C]thiamine and after centrifugation the radioactivity of the supernatant is measured. The method is simple and specific, and applicable over a thiamine concentration range 0.5-5 microM with a coefficient of variation typically below 5%. The gel is reusable and stable for several months. Applicability of the method for direct determination of thiamine in multivitamin pharmaceuticals is demonstrated.