Muography is a novel imaging technology based on particle physics instrumentation to reveal density structure of hill-sized objects. The cosmic muon flux is attenuated while penetrating into the ...ground, thus the differential local flux correlates with the overburden density-length. Underground muography exploits the close-to-zenith flux, while main challenges became portability, low power consumption, and robustness against the out-of-the-laboratory environment. Various fields could benefit from this non-invasive imaging, eg. speleology, mining, archeology, or industry. Portable gaseous tracking detector systems have been designed, built, and successfully used in several underground locations. This paper presents the designed portable muography systems, the main requirements, and measurement campaigns for calibration, natural caves, and cultural heritage.
The transition zone between Eastern Alps and Pannonian Basin is a key area for the investigation of the interplay between regional uplift, local tectonic subsidence and depositional environment. Our ...study area, the western margin of the Little Hungarian Plain, is characterized by gentle hills, plateaus and depressions, of which several are filled by lakes—including one of Austria’s largest and shallowest lakes, Lake Neusiedl. Geological investigation is hampered by the scarcity of outcrops, and thus direct observation of sedimentological or structural features is difficult. Despite a long research history in the area, a consistent landscape evolution model considering all relevant constraints is lacking so far. In this study, we apply multidisciplinary methods to decipher the complex tectonic and fluvial depositional evolution of the region. Local data from shallow-lake drilling and seismic investigation are combined with regional data from industrial seismics and core data to gain new insights into the latest Pannonian (Late Miocene) and Quaternary evolution. Shallow-lake seismic data show the erosionally truncated Pannonian sediments dipping and thickening toward southeast, toward the modern depocenter of the Little Hungarian Plain. Overlying Quaternary fluvial sediments show a very similar thickening trend except for the area on the plateau north of the lake indicating ongoing subsidence in major parts of the basin. Drill cores from locations along the lake seismic lines were analyzed concerning their age, mineralogy and heavy minerals and compared with outcrop samples from the surrounding plains and the plateau to derive indications on sediment provenance. A key observation is the apparent lack of a significant gravel layer on top of the tilted Pannonian sediments beneath Lake Neusiedl. Small-scale faults can be observed in the lake seismic sections along with key sedimentary features. Significant differences of the current elevation of the top Pannonian between the surrounding plains and the plateau indicate post-Pannonian normal faulting, which is a key process in shaping the present-day morphology of the region. Luminescence ages of samples from the Quaternary fluvial gravels on top of the Pannonian sediments are a significantly higher (>300 ka) compared to the gravels in the plain (102 ± 11 and 76 ± 8 ka), suggesting ongoing tectonic subsidence.
A portable cosmic muon detector has been developed for geophysical applications: searching for large scale underground rock/soil inhomogeneities and underground cavities. The designed muon telescope ...called a muon tomograph is based on the recently developed closed cathode chamber (CCC) technology, which provides a cheap, easy handling, portable, and power efficient detector system able to work even in extreme conditions (e.g. high humidity, low/high temperature). The muon telescope has a detection surface of approximately 0.1 m2 with a 10 mrad angular resolution. Tests have been performed in natural caves and artificial tunnel systems as well. In this paper a summary of the first results on tomographic cavities are presented and the geophysical and possible industrial use of the cosmic muon tomographic technology is indicated.
A portable cosmic particle tracking detector has been developed by the REGARD group with angular resolution of 10 mrad. The Close Cathode Chamber-based tracking system is optimized for environmental ...and geophysical applications with its weight of 15 kg and size of 51 cm × 43 cm × 32 cm. Our aim was to determine the cosmic background at the site of the proposed accelerator and experimental facilities at an approximate 50 meter depth in Felsenkeller, Dresden, Germany. Here, we present our high-precision muon flux measurements, which have been performed during 44 days in one of the tunnels. Angular acceptance of our mapping covered full 2π solid angle of the upper hemisphere. The maximum flux value is found to be below 2.5 m-2sr-1s-1.
The muon intensity and angular distribution in the shallow-underground laboratory Felsenkeller in Dresden, Germany have been studied using a portable muon detector based on the close cathode chamber ...design. Data has been taken at four positions in Felsenkeller tunnels VIII and IX, where a new 5 MV underground ion accelerator is being installed, and in addition at four positions in Felsenkeller tunnel IV, which hosts a low-radioactivity counting facility. At each of the eight positions studied, seven different orientations of the detector were used to compile a map of the upper hemisphere with 0.85∘ angular resolution. The muon intensity is found to be suppressed by a factor of 40 due to the 45 m thick rock overburden, corresponding to 140 m water equivalent. The angular data are matched by two different simulations taking into account the known geodetic features of the terrain: First, simply by determining the cutoff energy using the projected slant depth in rock and the known muon energy spectrum, and second, in a Geant4 simulation propagating the muons through a column of rock equal to the known slant depth. The present data are instrumental for studying muon-induced effects at these depths and also in the planning of an active veto for accelerator-based underground nuclear astrophysics experiments.
ABSTRACT
A flowstone from the central European Abaliget Cave (Mecsek Mts, Hungary) provides a record of uninterrupted calcite deposition between ∼160 and ∼124 ka, covering most of Marine Isotope ...Stage (MIS) 6 and part of 5e. δ18O values of three lateral drill cores show synchronous high‐frequency (millennial‐scale) variability during MIS 6, interpreted as stadials and interstadials, and a 3.4‰ rise at the MIS 6/5e boundary. The interstadials are mostly symmetrical in shape and show consistently lower δ18O values than calcite formed during MIS 5e. The rises (decreases) in δ18O are followed by drops (increases) in δ13C with a delay of 1–2 ka, implying enhanced (reduced) soil bioproductivity. This period of highly variable climate is bracketed by two broad δ18O minima. The first minimum between ∼160 and ∼148 ka coincided with a maximum in ice‐rafted detritus in the eastern North Atlantic. The second one from ∼134 to ∼129 ka occurred during Heinrich 11, before the rapid and large δ18O increase at ∼128 ka.
The balANZ trial recently reported that neutral pH, low glucose degradation product (biocompatible) peritoneal dialysis (PD) solutions significantly delayed anuria and reduced peritonitis rates ...compared with conventional solutions. This article reports a secondary outcome analysis of the balANZ trial with respect to peritoneal membrane function.
Adult, incident PD patients with residual renal function were randomized to receive either biocompatible or conventional (control) PD solutions for 2 years. Peritoneal equilibration tests were performed at 1, 6, 12, 18 and 24 months. Peritoneal small solute clearances and ultra-filtration (UF) were measured at 3, 6, 9, 12, 18 and 24 months.
Of the 185 patients recruited into the trial, 85 patients in the Balance group and 82 patients in the control group had peritoneal membrane function evaluated. Mean 4-h dialysate:plasma creatinine ratios (D:P Cr 4h) at 1 month were significantly higher in the Balance group compared with controls (0.67 ± 0.10 versus 0.62 ± 0.10, P = 0.002). Over the 2-year study period, mean D:P Cr 4 h measurements remained stable in the Balance group but increased significantly in controls difference -0.004 per month, 95% confidence interval (95% CI) -0.005 to -0.002, P < 0.001. Similar results were obtained for dialysate glucose ratios (D/D0 glucose). Peritoneal UF was significantly lower in the Balance group than in controls at 3 and 6 months. Over the 2-year study period, peritoneal UF increased significantly in the Balance group but remained stable in controls (difference 24 mL/day/month, 95% CI 9-39, P = 0.002). No differences in peritoneal small solute clearances, prescribed dialysate fill volumes or peritoneal glucose exposure were observed between the two groups.
Biocompatible and conventional PD solutions exert differential effects on peritoneal small solute transport rate and UF over time. Adequately powered trials assessing the impact of these differential membrane effects on PD technique and patient survival rates are warranted.
Summary of the long term data taking, related to one of the proposed next generation ground-based gravitational detector’s location is presented here. Results of seismic and infrasound noise, ...electromagnetic attenuation and cosmic muon radiation measurements are reported in the underground Matra Gravitational and Geophysical Laboratory near Gyöngyösoroszi, Hungary. The collected seismic data of more than two years is evaluated from the point of view of the Einstein Telescope, a proposed third generation underground gravitational wave observatory. Applying our results for the site selection will significantly improve the signal to noise ratio of the multi-messenger astrophysics era, especially at the low frequency regime.
A simple and cost-effective method for isolating and assaying microcystins, cyanobacterial toxins, by C-18 cartridges, DEAE-cellulose (DE-52) chromatography, and a mustard (
Sinapis alba L.) plant ...seedling test is described. The procedure results in a purity of up to 95-97% microcystin without the need for an HPLC system and justifies the use of the
S. alba L. seedling test in the quantitative assessment of the toxin with an IC
50 of 3 μg ml
−1 instead of the mouse intraperitoneal test.
A rapid and simple sample preparation method for plutonium determination in environmental samples by inductively coupled plasma sector field mass spectrometry (ICP-SFMS) and alpha-spectrometry is ...described. The developed procedure involves a selective CaF2 co-precipitation for preconcentration followed by extraction chromatographic separation. The proposed method effectively eliminates the possible interferences in mass spectrometric analysis and also removes interfering radionuclides that may disturb alpha-spectrometric measurement. For Pu, Pu and Pu limits of detection of 9.0 fg*g (0.021 mBq), 1.7 fg*g (0.014 mBq) and 3.1 fg*g (11.9 mBq) were achieved by ICP-SFMS, respectively, and 0.02 mBq by alpha-spectrometry. Results of certified reference materials agreed well with the recommended values.
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