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This paper describes technical details and new scientific opportunities offered by the new High Power Laser Facility at the ESRF, opened to users since 2022. This facility enables laser-induced dynamic compression experiments probed by ultra-fast X-ray Absorption Spectroscopy at beamline ID24-ED. This capability allows to reach and probe more extreme pressure and temperature states and higher strain rates with respect to static compression, addressing open questions in fundamental, planetary and material science. [ABSTRACT FROM AUTHOR]

Studying the properties and phase diagram of iron at high-pressure and high-temperature conditions has relevant implications for Earth's inner structure and dynamics and the temperature of the inner core boundary (ICB) at 330 GPa. Also, a hexagonal-closed packed to body-centered cubic (bcc) phase transition has been predicted by many theoretical works but observed only in a few experiments. The recent coupling of high-power laser with advanced x-ray sources from synchrotrons allows for novel approaches to address these issues. Here, we present a study on shock compressed iron up to 270 GPa and 5800 K probed by single-pulse (100 ps FWHM) x-ray absorption spectroscopy (XAS). Based on the analysis of the XAS spectra, we provide structural identification and bulk temperature measurements along the Hugoniot up to the melting. These results rule out the predicted transition to a high-temperature bcc phase and allow one to discriminate among existing equations of state models and melting curves. In particular, we report the first bulk temperature measurement in shock compressed iron on the melting plateau at 240(20) GPa and 5345(600) K. The melting curve resulting from our work extrapolates to a temperature of 6202(514) K at 330 GPa and represents a refined upper bound for the ICB temperature.

Anti-HLA class I monoclonal antibody (mAb) 01.65 inhibited phytohaemagglutinin (PHA)-induced human lymphocyte proliferation. The inhibitory effect was inversely correlated to the strength of the proliferative response. It was increased when lymphocytes were stimulated with suboptimal doses of PHA but it disappeared with supraoptimal doses. Proliferation inhibition was achieved by prolonging the cell cycle time and by slowing down its recruitment rate. The former effect was not restricted to the G1-phase but also included the S phase. These results support the idea that HLA class I molecules are important in the PHA-induced proliferation of human T-lymphocytes.

HLA class I antigens seem to be involved in the proliferative response of PHA-activated human T-lymphocytes. We have previously reported that the treatment of PHA-activated peripheral blood mononuclear cells (PBMC) with an anti-HLA class I monoclonal antibody, 01.65, (i) inhibits the tritiated thymidine incorporation, (ii) inactivates cytosolic protein kinase C (PKC) and (iii) causes an increase in the duration of the cell cycle. Northern Blot kinetic analysis of c-fos, c-myc, cdc2, IL-2R, c-myb, ODC, TK and H3, from 10 minutes to 120 hours, was performed in MAb 01.65 treated cultures. We found that the expression of four genes (c-myc, IL-2R, cdc2 and TK) was depressed 24 hours after PHA stimulation.

N-N-Staurosporine (STAR) inhibits in a dose dependent manner Tritiated-Thymidine (3H-TdR) incorporation in phytohemagglutinin (PHA) activated Peripheral Blood Mononuclear Cells (PBMC) treated with anti-HLA class I monoclonal antibody (MAb) 01.65 and its effect results competitive with MAb 01.65. Cytosolic and particulate Protein Kinase C (PKC) have been studied. Only when PKC particulate activity is no more detectable, the effect of STAR on 3H-TdR incorporation is evident.