Efficient Neutron Production from a Novel Configuration of Deuterium Gas-Puff Z-Pinch

A novel configuration of a deuterium z pinch has been used to generate fusion neutrons. Injecting an outer hollow cylindrical plasma shell around an inner deuterium gas puff, neutron yields from DD reactions reached Y-n = (2.9 +/- 0.3) x 10(12) at 700 ns implosion time and 2.7 MA current. Such a neutron yield means a tenfold increase in comparison with previous deuterium gas puff experiments at the same current generator. The increase of beam-target yields was obtained by a larger amount of current assembled on the z-pinch axis, and subsequently by higher induced voltage and higher energies of deuterons. A stack of CR-39 track detectors on the z-pinch axis showed hydrogen ions up to 38 MeV. Maximum neutron energies of 15 and 22 MeV were observed by radial and axial time-of-flight detectors, respectively. The number of DD neutrons per one joule of stored plasma energy approached 5 x 10(7). This implies that deuterium gas puff z pinches belong to the most efficient plasma-based sources of DD neutrons

Exploring the effects of topoisomerase II inhibitor XK469 on anthracycline cardiotoxicity and DNA damage

Anthracyclines, such as doxorubicin (adriamycin), daunorubicin, or epirubicin, rank among the most effective agents in classical anticancer chemotherapy. However, cardiotoxicity remains the main limitation of their clinical use. Topoisomerase IIβ has recently been identified as a plausible target of anthracyclines in cardiomyocytes. We examined the putative topoisomerase IIβ selective agent XK469 as a potential cardioprotective and designed several new analogues. In our experiments, XK469 inhibited both topoisomerase isoforms (α and β) and did not induce topoisomerase II covalent complexes in isolated cardiomyocytes and HL-60, but induced proteasomal degradation of topoisomerase II in these cell types. The cardioprotective potential of XK469 was studied on rat neonatal cardiomyocytes, where dexrazoxane (ICRF-187), the only clinically approved cardioprotective, was effective. Initially, XK469 prevented daunorubicin-induced toxicity and p53 phosphorylation in cardiomyocytes. However, it only partially prevented the phosphorylation of H2AX and did not affect DNA damage measured by Comet Assay. It also did not compromise the daunorubicin antiproliferative effect in HL-60 leukemic cells. When administered to rabbits to evaluate its cardioprotective potential in vivo, XK469 failed to prevent the daunorubicin induced cardiac toxicity in either acute or chronic settings. In the following in vitro analysis, we found that prolonged and continuous exposure of rat neonatal cardiomyocytes to XK469 led to significant toxicity. In conclusion, this study provides important evidence on the effects of XK469 and its combination with daunorubicin in clinically relevant doses in cardiomyocytes. Despite its promising characteristics, long-term treatments and in vivo experiments have not confirmed its cardioprotective potential

New fluorescent auxin probes visualise tissue‐specific and subcellular distributions of auxin in Arabidopsis

In a world that will rely increasingly on efficient plant growth for sufficient food, it is important to learn about natural mechanisms of phytohormone action. In this work, the introduction of a fluorophore to an auxin molecule represents a sensitive and non‐invasive method to directly visualise auxin localisation with high spatiotemporal resolution. The state‐of‐the‐art multidisciplinary approaches of genetic and chemical biology analysis together with live cell imaging, liquid chromatography–mass spectrometry (LC‐MS) and surface plasmon resonance (SPR) methods were employed for the characterisation of auxin‐related biological activity, distribution and stability of the presented compounds in Arabidopsis thaliana. Despite partial metabolisation in vivo, these fluorescent auxins display an uneven and dynamic distribution leading to the formation of fluorescence maxima in tissues known to concentrate natural auxin, such as the concave side of the apical hook. Importantly, their distribution is altered in response to different exogenous stimuli in both roots and shoots. Moreover, we characterised the subcellular localisation of the fluorescent auxin analogues as being present in the endoplasmic reticulum and endosomes. Our work provides powerful tools to visualise auxin distribution within different plant tissues at cellular or subcellular levels and in response to internal and environmental stimuli during plant development

New magnetic anomalies of the Outer Carpathians in NE Slovakia and their relationship to the Carpathian Conductivity Zone

A hitherto unknown magnetic anomaly has been detected in the framework of assembling magnetic picture of the Slovakian territory. The impressive magnetic object was recognized in the northeasternmost part of Slovakia within the area which is created by sediments of the Flysch belt. This is certain rarity because the Flysch sequence is practically without magnetic rocks. Due to this was obvious that anomaly is caused by an exotic rocks complex, intruded into Flysch sediments. The shape and the character of anomalous body indicated that source of anomaly is located in the shallow depth under surface relatively. The anomaly has been modelled in the 2D. Source of magnetic anomaly was interpreted as the product of Neogene volcanism – neck of intermediate rocks. Besides of this there were found out other minor anomalies within this area which might be caused also by smaller subvolcanic bodies. The Carpathian Conductivity Anomaly is located in the proximity of new observed magnetic anomalies. Due to this fact it is possible to open new view on the importance of this zone. In the case of justification of such interpretation the area might be interesting for its potential prognosis of hydrocarbons occurrence, metallogenetic prominence, as well as possibilities for underground storage of carbon dioxide

Progress in MJ plasma focus research at IPPLM

The results of studies of the plasma dynamics and neutron emission on a PF-1000 facility in the stage of pinch formation are presented. The measurements were performed using various modifications of the calibrated magnetic probes, 16 frame interferometry, silver activation counters and photomultiplier tube (PMT) neutron probes. The current measurements at a distance of 40 mm from the axis of the electrodes was measured. This dependence agrees well with the known scaling, Yn similar to I4. The evolution plasma density during pinch formation and a neutron emission were study