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Equation of state measurements at Jovian or stellar conditions are currently conducted by dynamic shock compression driven by multi-kilojoule multi-beam nanosecond-duration lasers. These experiments require precise design of the target and specific tailoring of the spatial and temporal laser profiles to reach the highest pressures. At the same time, the studies are limited by the low repetition rate of the lasers. Here, we show that by the irradiation of a thin wire with single-beam Joule-class short-pulse laser, a converging cylindrical shock is generated compressing the wire material to conditions relevant to the above applications. The shockwave was observed using Phase Contrast Imaging employing a hard X-ray Free Electron Laser with unprecedented temporal and spatial sensitivity. The data collected for Cu wires is in agreement with hydrodynamic simulations of an ablative shock launched by highly impulsive and transient resistive heating of the wire surface. The subsequent cylindrical shockwave travels toward the wire axis and is predicted to reach a compression factor of 9 and pressures above 800 Mbar. Simulations for astrophysical relevant materials underline the potential of this compression technique as a new tool for high energy density studies at high repetition rates. Hard X-ray free electron lasers allow new insights into dense matter dynamics. Here, the authors show that a single-beam, short-pulse laser can generate a converging cylindrical shock in a thin wire, providing a new method for high energy density research with improved repetition rates. [ABSTRACT FROM AUTHOR]

In this paper, we show that supercritical fluids have a greater significance in the generation of pegmatites, and for ore-forming processes related to granites than is usually assumed. We show that the supercritical melt or fluid is a silicate phase in which volatiles; principally H2O are completely miscible in all proportions at magmatic temperatures and pressures. This phase evolves from felsic melts and changes into hydrothermal fluids, and its unique properties are particularly important in sequestering and concentrating low abundance elements, such as metals. In our past research, we have focused on processes observed at upper crustal levels, however extensive work by us and other researchers have demonstrated that supercritical melt/fluids should be abundant in melting zones at deep-crustal levels too. We propose that these fluids may provide a connecting link between lower and upper crustal magmas, and a highly efficient transport mechanism for usually melt incompatible elements. In this paper, we explore the unique features of this fluid which allow the partitioning of various elements and compounds, potentially up to extreme levels, and may explain various features both of mineralization and the magmas that produced them. [ABSTRACT FROM AUTHOR]

This study aims at evaluating the capabilities of synchrotron radiation micro X-ray fluorescence spectrometry (SR micro-XRF) for qualitative and semi-quantitative elemental mapping of the distribution of actinides in human tissues originating from individuals with documented occupational exposure. The investigated lymph node tissues were provided by the United States Transuranium and Uranium Registries (USTUR) and were analyzed following appropriate sample pre-treatment. Semi-quantitative results were obtained via calibration by external standards and demonstrated that the uranium concentration level in the detected actinide hot spots reaches more than 100 μg/g. For the plutonium hot spots, concentration levels up to 31 μg/g were found. As illustrated by this case study on these unique samples, SR micro-XRF has a high potential for this type of elemental bio-imaging owing to its high sensitivity, high spatial resolution, and non-destructive character. [ABSTRACT FROM AUTHOR]

The promoter of the Mucor circinelloides gpd1 gene encoding glyceraldehyde-3-phosphate dehydrogenase (gpd1P) was recently cloned and used for the production of recombinant proteins, such as the Aspergillus niger glucose oxidase 1 (GOX). This represents the first example of the application of a strong and regulated promoter from this fungus for recombinant protein production. The original 741-bp gpd1P promoter fragment conferred hexose-dependent expression of GOX in M. circinelloides. To understand the regulatory mechanisms involved in gpd1P-driven expression and to develop improved promoter fragments, deletion derivatives of gpd1P were constructed. These derivatives were fused to the A. niger gox1 gene and used to construct strains containing a single copy of the expression cassette. GOX activity was detected in strains containing the full-length gpd1P and also in strains containing a 713-bp or a 361-bp derivative. Expression levels for the 361-bp derivative were high and comparable, regardless of the carbon source used. This promoter represents a useful derivative for constitutive heterologous gene expression in M. circinelloides. [ABSTRACT FROM AUTHOR]

In the original publication, there are some missing data in Table 1 and incorrect data in Table 2. [ABSTRACT FROM AUTHOR]