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This work presents first insights into the dynamics of free-surface release clouds from dynamically compressed polystyrene and pyrolytic graphite at pressures up to 200 GPa, where they transform into diamond or lonsdaleite, respectively. These ejecta clouds are released into either vacuum or various types of catcher systems, and are monitored with high-speed recordings (frame rates up to 10 MHz). Molecular dynamics simulations are used to give insights to the rate of diamond preservation throughout the free expansion and the catcher impact process, highlighting the challenges of diamond retrieval. Raman spectroscopy data show graphitic signatures on a catcher plate confirming that the shock-compressed PS is transformed. First electron microscopy analyses of solid catcher plates yield an outstanding number of different spherical-like objects in the size range between ten(s) up to hundreds of nanometres, which are one type of two potential diamond candidates identified. The origin of some objects can unambiguously be assigned, while the history of others remains speculative.

In this presentation we provide an overview of the commissioning and first user experiment of ReLaX in combination with the XFEL beam. We will introduce the setup and laser parameters. We will show the established standard setup combining small-angle x-ray scattering (SAXS), phase-contrast imaging (PCI) and spectroscopy techniques. Finally we will show examples of the data obtained in the interaction of the ReLaX laser with targets of interested for the short-pulse laser community.

Extreme states of matter exist throughout the universe e.g. inside planetary cores, stars or astrophysical jets. Such conditions can be generated in the laboratory in the interaction of powerful lasers with solids. Yet, the measurement of the subsequent plasma dynamics with regard to density, temperature and ionization is a major experimental challenge. However, ultra-short X-ray pulses provided by X-ray free electron lasers (XFELs) allow for dedicated studies, which are highly relevant to study laboratory astrophysics, laser-fusion research or laser-plasma-based particle acceleration. Here, we report on experiments that employ a novel ultrafast method, which allows to simultaneously access temperature, ionization state and nanometer scale expansion dynamics in high-intensity laser-driven solid-density plasmas with a single X-ray detector. Using this method, we gain access to the expansion dynamics of a buried layer in compound samples, and we measure opacity changes arising from bound-bound resonance transitions in highly ionized copper. The presence of highly ionized copper leads to a temperature estimate of at least 2 million Kelvin already after the first 100 femtoseconds following the high-intensity laser irradiation. More specifically, we make use of asymmetries in small-angle X-ray scattering (SAXS) patterns, which arise from different spatial distributions of absorption and scattering cross sections in nanostructured grating samples when we tune an XFEL to atomic resonant energies of copper. Thereby, changes in asymmetry can be connected with the evolution of the plasma expansion and ionization dynamics. The potential of XFEL-based resonant SAXS to obtain three-dimensional ultrafast, nanoscopic information on density and opacity may offer a unique path for the characterization of dynamic processes in High Energy Density plasmas.

Large clinical trials testing hydrocortisone therapy in septic shock have produced conflicting results. Subgroups may benefit of hydrocortisone treatment depending on their individual immune response. We performed an exploratory analysis of the database from the international randomized controlled clinical trial Corticosteroid Therapy of Septic Shock (CORTICUS) employing machine learning to a panel of 137 variables collected from the Berlin subcohort comprising 83 patients including demographic and clinical measures, organ failure scores, leukocyte counts and levels of circulating cytokines. The identified theranostic marker was validated against data from a cohort of the Hellenic Sepsis Study Group (HSSG) (n = 246), patients enrolled in the clinical trial of Sodium Selenite and Procalcitonin Guided Antimicrobial Therapy in Severe Sepsis (SISPCT, n = 118), and another, smaller clinical trial (Crossover study, n = 20). In addition, in vitro blood culture experiments and in vivo experiments in mouse models were performed to assess biological plausibility. A low serum IFNγ/IL10 ratio predicted increased survival in the hydrocortisone group whereas a high ratio predicted better survival in the placebo group. Using this marker for a decision rule, we applied it to three validation sets and observed the same trend. Experimental studies in vitro revealed that IFNγ/IL10 was negatively associated with the load of (heat inactivated) pathogens in spiked human blood and in septic mouse models. Accordingly, an in silico analysis of published IFNγ and IL10 values in bacteremic and non-bacteremic patients with the Systemic Inflammatory Response Syndrome supported this association between the ratio and pathogen burden. We propose IFNγ/IL10 as a molecular marker supporting the decision to administer hydrocortisone to patients in septic shock. Prospective clinical studies are necessary and standard operating procedures need to be implemented, particularly to define a generic threshold. If confirmed, IFNγ/IL10 may become a suitable theranostic marker for an urging clinical need. © Copyright © 2021 König, Kolte, Ahlers, Oswald, Krauss, Roell, Sommerfeld, Dimopoulos, Tsangaris, Antoniadou, Jaishankar, Bogatsch, Löffler, Rödel, Garcia-Moreno, Tuchscherr, Sprung, Singer, Brunkhorst, Oppert, Gerlach, Claus, Coldewey, Briegel, Giamarellos-Bourboulis, Keh and Bauer.

We present structure measurements of biaxially orientated polyethylene terephthalate (PET, (C10H8O4)n , also called mylar) shock-compressed to (155+/-20) GPa and (6000+/-1000) K using in situ X-ray diffraction. Comparing to density functional theory molecular dynamics simulations, we find a highly correlated liquid that exhibits a temperature signficantly lower than predicted by some equation-of-state tables, which underlines the influence of complex chemical interactions in this regime. Indeed, at the inferred temperature and pressure, formation of nanodiamonds may be expected as recently observed in polystyrene at similar conditions. While some hints of diamond formation from PET are visible in the diffraction data, the strong liquid correlations prevent a conclusive statement as to whether diamonds are formed inside the sample volume.

This repository contains raw-data related to our publication "Measuring the structure and equation of state of polyethylene terephthalate at megabar pressures". The XRD data in the "LCLS" folder is accompanied with a "calibration.poni" file that provides information about the experiment's geometry and can be used in pyFAI (GitHub page) or Dioptas (GitHub page) to integrate the two-dimensional data azimuthally. Integrated XRD data after background-subtraction and filter-corrections is presented in Fig. 2 and 3 of the manuscript while 2D data of run 215 is used in Fig. 1. The "shotlist.csv" file contains information about the relative X-ray to drive-laser timing, shot-type and X-ray energy for the individual events. VISAR, SOP and reflectivity measurements can be found in the "LULI" directory. 2ω-VISAR and SOP datasets of shot 08 are displayed as inserts in Fig. 5 (the first after performing a ghost-fringe subtraction). "shotlist.csv" provides additional parameters. The DFTMD folder contains the results of our density functional theory molecular dynamics simulation. In the "XRD" subdirectory, "wrofk_mylar_chomd*.dat" files can be found in which the quantities to calculate the lineouts in Fig. 3 and 4 are saved for given temperatures, pressures and densities. The header of those files is given in "header.txt" and additional information about the conditions and settings for individual calculations can be obtained from "param_mylar_md.txt". The dataset for the Hugoniot curve from our DFT-MD equation-of-state (which is plotted in Fig. 5) is provided in the "Hugoniot" sub-folder.

Resonant Small-angle x-ray scattering raw data obtained in measurements at MEC at LCLS and evalutation of the asymmetry in the scattering patterns. The data set is structured in case 1/Si-Cu-compound targets and case 2/Cu-only-targets as presented in the publication for on- and off-resonant XFEL probe energies.

The combination of ultra-intense lasers with x-ray free-electron lasers (XFELs) opens up a variety of applications in plasma and shock physics. Many phenomena during the laser-target interaction happen on short time scales in the range from femto- to picoseconds and length scales of tens of nanometers to a few micrometers. Unlike the ultra-short, highly coherent x-ray pulse, optical methods or conventional continuous x-ray sources cannot probe the dynamics of the bulk material with sufficient temporal and spatial resolution. Here we will show the potential of SAXS in combination with short-pulse laser experiments. With this method it is possible to draw conclusions about the electron density distribution in the target by analyzing the XFEL diffraction pattern in the vicinity of the direct beam. A setup to perform such SAXS experiments was developed and optimized during a beamtime at the Matter in Extreme Conditions instrument (MEC) at the Linear Coherent Light Source (LCLS) in Stanford. We will discuss the setup and present a preliminary analysis of the data obtained during this experiment.

In this work, we demonstrate simultaneous phase-contrast imaging (PCI) and X-ray diffractionfrom shock compressed matter at the Matter in Extreme Conditions endstation, at the LinacCoherent Light Source (LCLS). We utilize the chromaticity from compound refractive X-ray lensesto focus the 24.6 keV 3rd order undulator harmonic of the LCLS to a spot size of 5lm on target toperform X-ray diffraction. Simultaneous PCI from the 8.2 keV fundamental X-ray beam is used tovisualize and measure the transient properties of the shock wave over a 500lm field of view.Furthermore, we demonstrate the ability to extend the reciprocal space measurements by 5 Angstroem, rel-ative to the fundamental X-ray energy, by utilizing X-ray diffraction from the 3rd harmonic of theLCLS.

Nanometer probing of ultrahigh intensity ultrashort pulse laser interaction with solid density plasmas, by SAXS using XFELs

Raw data, lineouts and fits for the publication

We present an approach for reconstructing real space information from small angle x-ray scattering images that utilizes reduced models to describe the scattering distribution. This implies a massive reduction of the reconstruction space dimensionality. First reconstruction results for experimental data are shown.

Molecular analysis indicates that African material previously referred to Amietophrynus maculatus (Hallowell, 1854; now Sclerophrys maculata), is divisible into two distinct clades: a Western Clade from Cameroon westwards and an Eastern Clade from Central African Republic eastwards, and Uganda southwards to South Africa, extending to Angola-Namibia. Preliminary morphological and bioacoustic data support this division. The two clades are recognised here as two separate species. The Western species retains the name S. maculata, with Hallowell's designated type locality of Liberia. The Eastern Clade retains the name published by Mertens (1937), S. pusilla. It is noted that a type specimen of S. maculata cannot be traced and is presumed lost; the so-called syntypes in the Philadelphia Academy of Natural Sciences are not the material described by Hallowell. None of these have been designated as a neotype, consequently a specimen from Liberia in the collection of the Natural History Museum, London, is designated here as the neotype of S. maculata.

Concept of solid plasma diagnostics with Small Angle X-ray Scattering, experimental feasibility of SAXS at femtosecond and nanosecond laser driven solid material, and beyond electron-electron correlations: Resonant SAXS for ion distribution measurements

Specimens from across the range of the Hyperolius nasutus species group were sequenced for two mitochondrial genes and one nuclear gene. Advertisement calls were recorded from the same specimens where possible, and morphological characters were compared. Bayesian inference and maximum likelihood produced a tree indicating 16 clades. The clades show little or no overlap in combinations of 16S sequence difference, shared tyr haplotypes, advertisement call parameters, snout profiles and webbing. On the basis of these data we recognise H. acuticeps, H. adspersus, H. benguellensis, H. dartevellei, H. igbettensis, H. nasutus, H. nasicus, H. poweri, H. viridis and describe six new species: Hyperolius friedemanni sp. nov. Mercurio & Rödel, Hyperolius howelli sp. nov. Du Preez & Channing, Hyperolius inyangae sp. nov. Channing, Hyperolious jacobseni sp. nov. Channing, Hyperolius rwandae sp. nov. Dehling, Sinsch, Rödel & Channing, and Hyperolius lupiroensis sp. nov. Channing. Hyperolius lamottei is confirmed to be outside the H. nasutus group clade. Hyperolius granulatus, H. oxyrhynchus, H. punctulatus and H. sagitta are assigned as junior synonyms. As our results are based on a small number of specimens, these hypotheses await testing with larger sample sizes and more characters. A species distribution model suggests where outlier populations might be found http://www.mapress.com/j/zt/ http://mapress.com/zootaxa/2013/f/z03620p350f.pdf http://dx.doi.org/10.11646/zootaxa.3620.3.1

We report on the amphibians of three sites in the Fouta Djallon highlands in central-northern Guinea. During our survey we recorded at least 25 frog species, including two first country records (Kassina fusca and Leptopelis bufonides) and one species new to science (Conraua sp.). Most of the recorded frogs were typical savanna or farmbush species with a distribution range that exceeds West Africa. Only a few species were more closely connected to forest habitats. For several species our records in the Fouta Djallon represent large range extensions. Despite the generally high degradation level of forests in the Fouta Djallon, the investigated sites all still harboured typical forest frogs and thus may represent last islands of forest in a nowadays savanna dominated landscape. All sites therefore have a high potential for conservation, especially the forest surrounding the Saala Waterfalls.

Astylosternus laticephalus sp. nov. Rödel, Hillers, Leaché, Kouamé, Ofori-Boateng, Diaz & Sandberger is described fromeastern Ivory Coast and western and central Ghana, and compared to Astylosternus occidentalis Parker, 1931 from thewestern part of the Upper Guinea forest zone (western Ivory Coast, Liberia, Guinea and Sierra Leone). Based on a com-prehensive sample, including specimens from the entire range, the latter species is re-described. The new species is char-acterized by a body shape typical for frogs of the genus Astylosternus, but has an exceptionally broad head, i.e. broaderthan in A. occidentalis. The basic dorsal pattern of A. laticephalus sp. nov. consists of a brownish to brownish red colour-ation with distinct red dots (red dots are only rarely present in A. occidentalis). The new species has bicoloured eyes withthe lower part of the iris being grey, the upper third of the iris is orange to red (A. occidentalis always has a uniform greyishiris). Males of the new species lack spines on the throat, belly (always present in A. occidentalis males), and a layer ofblack nuptial skin in the pectoral region (present in male A. occidentalis from western Guinea). Astylosternus laticephalussp. nov. differs from A. occidentalis by a mean pairwise genetic distance of 3.2% in the investigated part of the mitochon-drial 16S rRNA gene. Genetic divergence to the morphologically most similar Central African species, A. diadematus,was 11.9%. We briefly discuss the phylogenetic position of West African Astylosternus, hint on the possibility that thegenus might be paraphyletic and discuss the biogeography of West African Astylosternus, in particular with respect to forest cover fluctuations in the past.