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Turbulence is ubiquitous in the universe and in fluid dynamics. It influences a wide range of high energy density systems, from inertial confinement fusion to astrophysical-object evolution. Understanding this phenomenon is crucial, however, due to limitations in experimental and numerical methods in plasma systems, a complete description of the turbulent spectrum is still lacking. Here, we present the measurement of a turbulent spectrum down to micron scale in a laser-plasma experiment. We use an experimental platform, which couples a high power optical laser, an x-ray free-electron laser and a lithium fluoride crystal, to study the dynamics of a plasma flow with micrometric resolution (~1μm) over a large field of view (>1 mm2). After the evolution of a Rayleigh–Taylor unstable system, we obtain spectra, which are overall consistent with existing turbulent theory, but present unexpected features. This work paves the way towards a better understanding of numerous systems, as it allows the direct comparison of experimental results, theory and numerical simulations. Turbulence effects explored use macroscale systems in general. Here the authors generate a turbulent plasma using laser irradiation of a solid target and study the dynamics of the plasma flow at the micron-scale by using scattering of an XFEL beam. [ABSTRACT FROM AUTHOR]

Well-aligned anatase and rutile TiO2 nanorods and nanotubes with a diameter of about 80–130 nm have successfully been fabricated via sol-gel template method. The prepared samples were characterized by using thermogravimetric (TG) and differential thermal analysis (DTA), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy dispersive X-ray spectroscopy (EDS). The XRD results indicated that the TiO2 nanorods were crystallized in the anatase and rutile phases, after annealing at 400–800 °C for different periods of time from 0.2 to 10 h. [ABSTRACT FROM AUTHOR]

c-Myc N-terminal conserved domains, MbI and MbII, are essential for c-Myc-mediated transformation and transactivation. These domains recruit the STAGA (SPT3-TAF9-GCN5-acetyltransferase) coactivator complex, but not TFTC (TATA-binding protein-free TAF-containing) to the target gene promoter. Although components of this complex are well conserved between yeast and mammals, four mammalian orthologs of yeast SPT8, SPT20, SGF11 and SGF29 remain to be identified. Here, we isolated a rat ortholog of yeast SGF29, a component of yeast SAGA (SPT-ADA-GCN5-acetyltransferase) complex. Both rat (r) SGF29 and c-myc mRNAs were overexpressed in five out of the eight tested rodent tumor cells. rSGF29 directly interacted with rADA3 and co-immunoprecipitated with two other TFTC/STAGA components, rGCN5 and rSPT3. rSGF29 was recruited to the c-Myc target gene promoters together with c-Myc, and it activated c-Myc target gene expressions. Downregulation of rSGF29 suppressed the expression of c-Myc target genes and inhibited anchorage-independent growth and tumorigenicity and lung metastasis of rat hepatoma K2 cells when injected into nude mice. These results show that rSGF29 is a novel component of TFTC/STAGA complexes and could be involved in the c-Myc-mediated malignant transformation.Oncogene (2007) 26, 5626–5634; doi:10.1038/sj.onc.1210349; published online 5 March 2007 [ABSTRACT FROM AUTHOR]

In most protocols of peptide-based vaccination, no consideration has been paid to whether or not peptide-specific cytotoxic T-lymphocyte (CTL) precursors are pre-existent in cancer patients. Initiation of immune boosting through vaccination is better than that of immune priming to induce prompt and strong immunity. In this study, 10 human histocompatibility leukocyte antigen-A24+ patients with advanced colorectal carcinomas were treated with up to four peptides that had been positive for pre-vaccination measurement of peptide-specific CTL precursors in the circulation (CTL precursor-oriented peptide vaccine). No severe adverse effect was observed, although local pain and fever of grade I or II were observed. Post-vaccination peripheral blood mononuclear cells (PBMCs) from five patients demonstrated an increased peptide-specific immune response to the peptides. Increased CTL response to cancer cells was detected in post-vaccination PBMCs of five patients. Antipeptide immunoglobulin G became detectable in post-vaccination sera of seven patients. Three patients developed a positive delayed-type hypersensitivity response to at least one of the peptides administrated. One patient was found to have a partial response; another had a stable disease, sustained through 6 months. These results encourage further development of CTL precursor-oriented vaccine for colorectal cancer patients.British Journal of Cancer (2004) 90, 1334-1342. doi:10.1038/sj.bjc.6601711 www.bjcancer.com Published online 2 March 2004 [ABSTRACT FROM AUTHOR]

Development of therapeutic vaccines is one of the major areas of tumour immunotherapy today. However, clinical trials of peptide-based cancer vaccines have rarely resulted in tumour regression. This failure might be due to an insufficient induction of cytotoxic T lymphocytes in the current regimes, in which cytotoxic T lymphocytes-precursors in pre-vaccination peripheral blood mononuclear cells are not measured. Initiation of immune-boosting through vaccination could be better than that of immune-priming with regard to induction of prompt and strong immunity. If this is also the case for therapeutic vaccines, pre-vaccination measurement of peptide-specific cytotoxic T lymphocytes-precursors will be important. In the present study, we investigated whether cytotoxic T lymphocytes-precursors reacting to 28 kinds of peptides of vaccine candidates (13 and 15 peptides for HLA-A24(+) and HLA-A2(+) patients, respectively) were detectable in pre-vaccination peripheral blood mononuclear cells of 80 cancer patients. Peptide-specific cytotoxic T lymphocytes-precursors were found to be detectable in peripheral blood mononuclear cells of the majority of cancer patients (57 out of 80 cases, 71%). The mean numbers of positive peptides were 2.0 peptides per positive case. Peripheral blood mononuclear cells incubated with positive peptides, not with negative peptides, showed significant levels of HLA-class-I-restricted cytotoxicity to cancer cells. The profiles of positive peptides entirely varied among patients, and were not influenced by the cancer origin. These results may provide a scientific basis for the development of a new approach to cancer immunotherapy, e.g.) cytotoxic T lymphocytes-precursor-oriented peptide vaccine. [ABSTRACT FROM AUTHOR]

To study changes in the concentration of suspended particulate matter (SPM) in indoor and outdoor air, a new portable sampler (AND sampler) was designed that could separately collect particles exhibiting aerodynamic diameters of > 10 μm, 2-10 μm, and < 2 μm. The relationship between the airborne particle concentration in indoor air and that in outdoor air varied with the aeordynamic diameter of the particles. The concentration of SPM in the indoor air increased in proportion to that in the outdoor air. The concentration of polycyclic aromatic hydrocarbons (PAH) in SPM also varied with the aerodynamic diameter of the particles. Fine particles exhibiting an aerodynamic diameter of < 2 μm contained high concentration of PAH. The concentrations of benzo( k)fluoranthene, benzo( a)pyrene, and benzo ( ghi) perylene in indoor air increased in proportion to those in outdoor air. [ABSTRACT FROM AUTHOR]

Long-term fatigue tests of polycrystalline 70/30 brass were carried out under low strain amplitudes in vacuum, and dislocation structures of the strain localized regions developed were examined by means of transmission electron microscopy In the planar dislocation structures, the strain localized regions (SLRs) bounded by a pair of parallel active glide layers were frequently observed in favorably oriented grains. Where the SLRs impinge on grain boundaries (GBs), extrusion-type deformations were sometimes formed notwithstanding the restraints of the neighboring grains. On the basis of observations, the mechanism of crack initiation at the GB is discussed. [ABSTRACT FROM AUTHOR]

The correlation between the formation of extrusions and the dislocation structures in polycrystalline 85/15 brass subjected to a long term stress cycling with a low strain amplitude in vacuum was examined by means of transmission electron microscopy. The overall dislocation structures consisted of two types of structures, i.e., copper-type and 70/30 brass-type. Within them the strain localized regions bounded by two closely located active slip layers were frequently observed. In these boundary layers appeared a fringe pattern which was suggestive of intensive slip. Extrusions were formed in close association with the two closely located layers, and the initiation and growth of fatigue cracks occurred along one of them. On the basis of these observations, the mechanism of extrusion formation and of fatigue crack initiation are discussed. [ABSTRACT FROM AUTHOR]

Observations of dislocation structures around the fatigue cracks in the early stage in polycrystalline copper were made through an ultrahigh voltage electron microscope operating at 2000 kV. Ladder like structures and initial cracks within them were fre-quently observed. These dislocation structures were formed prior to the crack initia-tion, and the crack was initiated and propagated within these structures accompanied by no appreciable dislocation entanglements in the earliest stage. On the other hand, cell structures were observed around the cracks which appeared to have grown into the sub-sequent stage (the stage between Stages I and II). Cell size ahead of the crack tip was not so small, and it seemed that the crack was able to propagate across the cells. On the basis of these observations, the mechanisms of fatigue crack initiation and propagation in the early stage in copper bulk-specimens are briefly discussed. [ABSTRACT FROM AUTHOR]

Thin foils containing sharp fatigue cracks were prepared from bulk specimens of iron by means of jet electropolishing under a special condition, and microstructures both immediately ahead of the crack tips and adjacent to the crack sides were observed through an electron microscope operating at 2000 kV. It was found that dislocation tangles of high density were developed around the crack tips, and a fine cell structure in the areas near the sides of the cracks. The dislocations of high density ahead of the crack tips seemed to rearrange into cell walls to form small cells, in a relatively short span of time after the crack tip has passed. [ABSTRACT FROM AUTHOR]

This paper shows that, in fatigue tests on copper, a great number of cycles beyond expectation is necessary for determining the fatigue limit. An ultrahigh frequency fatigue testing machine was used and S-N curves covering 10 cycles were obtained for annealed specimens and for stretched ones. In annealed copper, the fatigue limit appeared at about 9.8 × 10 cycles. Observations were made on the development of slip bands and substructures in the course of a test at the strain level (3.8 × 10) of the fatigue limit. The slip bands continued to develop up to about 9 × 10 cycles, but remained unchanged if further cycled. On a searching examination of the behavior of microcracks, one end of which stayed in a grain without propagation, it was proved that fatigue hardening was responsible for the existence of the fatigue limit. Contrary to expectation, cell structures were found after 10 cycles in such a low strain fatigue. In stretched copper, however, microcracks continued to grow even in the stage beyond 10 cycles when fatigued at the strain level of the fatigue limit inferred from its S-N curve. [ABSTRACT FROM AUTHOR]

Transfer parameters for dose assessment such as deposition velocity ( Vg), fraction of directly deposited on plants to the edible parts ( r) and transfer factors ( Biv) have been evaluated. Deposition velocity under drying and wet conditions was evaluated about 0.8 cm/s. Fraction of directly deposited on plants and transfer factors in plants showed a lognormal distribution. Geometric means of fraction of deposited in rice, leafy vegetable and grass were <9·10−3, 0.2 and about 9·10−2, respectively. Geometric mean of the transfer factor in leafy vegetable was about 3·10−2. These results were compared with the parameters given in the US NRC Regulatory Guide and previous literature values. The results showed that the fraction of directly deposited on plants were smaller than the recommended value in the NRC Regulatory Guide. They also showed that the deposition velocity and transfer factors were almost similar to the results reported in the literature. [ABSTRACT FROM AUTHOR]

We report a carcinoid tumor in the mucosal layer of the esophagus of a 63-year-old man. Barium X-ray and endoscopy indicated the tumor to be a polypoid lesion in the lower esophagus. Endoscopic ultrasonography (EUS) demonstrated the lesion to be a sharply demarcated hyperechoic tumor in the mucosal layer. Biopsy yielded a diagnosis carcinoid of the esophagus. In the resected specimen of the esophagus, the tumor was 11 mm in longest dimension with a shallow depression on it smooth surface. Histologically, the tumor was located in the mucosal layer, as shown by EUS, and was composed of small round cells which were positive for argyrophil, but not argentaffine. Carcinoid tumor of the esophagus found at an early stage, and localized in the lamina propria layer, is very rare. The present case is the second report in Japan. [ABSTRACT FROM AUTHOR]

High resolution X-ray imaging is crucial for many high energy density physics (HEDP) experiments. Recently developed techniques to improve resolution have, however, come at the cost of a decreased field of view. In this paper, an innovative experimental detector for X-ray imaging in the context of HEDP experiments with high spatial resolution, as well as a large field of view, is presented. The platform is based on coupling an X-ray backligther source with a Lithium Fluoride detector, characterized by its large dynamic range. A spatial resolution of 2 µm over a field of view greater than 2 mm2 is reported. The platform was benchmarked with both an X-ray free electron laser (XFEL) and an X-ray source produced by a short pulse laser. First, using a non-coherent short pulse laser-produced backlighter, reduced penumbra blurring, as a result of the large size of the X-ray source, is shown. Secondly, we demonstrate phase contrast imaging with a fully coherent monochromatic XFEL beam. Modeling of the absorption and phase contrast transmission of X-ray radiation passing through various targets is presented. [ABSTRACT FROM AUTHOR]