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Durability tests of thermal protection system (TPS) materials for space vehicles is of paramount importance in developing TPS materials. The limits of the presently used techniques and the need for higher accuracy and precision demand new reliable and more sensitive measurement methods. In this paper we present the validation of a new on-line and non intrusive technique to estimate the TPS material recession rate which exploits the surface layer implantation of radioactive 7Be ions and the measurement of its characteristic γ-rays during the recession test. [ABSTRACT FROM AUTHOR]

Italy built and commissioned 4 nuclear power plants between 1958-1978, which delivered a total of 1500 MW. All four were closed down after the Chernobyl accident following a referendum in 1987. One of the plants was Garigliano, commissioned in 1959. This plant used a 160 MW BWR1 (SEU of 2.3 %) and was operational from 1964 to 1979, when it was switched off for maintenance. It was definitively stopped in 1982, and is presently being decommissioned. We report here details on the chemistry procedure and on the measurements for soil samples, collected up to 4.5 km from the Nuclear Plant. A comparison between uranium (238U) concentration as determined by means of AMS (Accelerator Mass Spectrometry) and by ICP-MS (Inductively Coupled Plasma-Mass Spectrometry) techniques respectively at the ANU (Australian National University) and at the Ecowise company in Canberra, Australia, is reported, as well as 236U and 239;240Pu concentration results detected by AMS. 236U/238U and 240Pu/239Pu isotopic ratios by means of AMS are also provided. A contamination from Chernobyl is visible in the 137Cs/239+240Pu activity ratio measurements.

Accelerator Mass Spectrometry (AMS) is presently the most sensitive technique for the measurement of long-lived actinides, e.g. 236U and xPu isotopes. A new actinide AMS system, based on a 3-MV pelletron tandem accelerator, is operated at the Center for Isotopic Research on Cultural and Environmental Heritage (CIRCE) in Caserta, Italy. In this paper we report on the procedure adopted to increase the 236U abundance sensitivity as low as possible. The energy and position determinations of the 236U ions, using a 16-strip silicon detector have been obtained. A 236U/238U isotopic ratio background level of about 2.9×10−11 was obtained, summing over all the strips, using a Time of Flight-Energy (TOF-E) system with a 16-strip silicon detector (4.9×10−12 just with one strip).

Tandem electrostatic accelerators often require the flexibility to operate at variety of terminal voltages to cater for various user needs. However beam transmission will only be optimal for a limited range of terminal voltages. This paper describes a focussing system that greatly expands the range of terminal voltages for optimal transmission. This is achieved by controlling the gradient of the entrance of the low-energy tube providing an additional controllable focusing element. Up to 150 kV is applied to the fifth electrode of the first unit of the accelerator tube giving control of the tube entrance lens strength. Beam tests to confirm the efficacy of the lens have been performed. These tests demonstrate that the entrance lens control eliminates the need to short out sections of the tube for low terminal voltage operation.

Retraction Note: Direct measurements of the 12C + 12C reactions cross-sections towards astrophysical energies After publication, we discovered a mistake in the script used to calculate beam energy losses from tabulated stopping powers. We deeply regret any inconvenience that this retraction may cause, and we apologize to the scientific community and to the readers of EPJA for any harm that may have been caused by the publication of this paper. [Extracted from the article]

The assessment of the radiological impact of a decommissioned nuclear power plant is presented here through the results of an environmental monitoring survey carried out in the area surrounding the Garigliano Power Plant. The levels of radioactivity in soil, water, air and other environmental matrices are shown, in which α, β and γ activity and the γ equivalent dose rate are measured. Radioactivity levels of the samples from the Garigliano area are analyzed and then compared with those from a control zone situated more than 100 km away. Moreover, a comparison is made with a previous survey carried out in 2001. The analyses and comparisons show no significant alteration in the radiological characteristics of the area surrounding the plant, with the overall radioactivity depending mainly on the global fallout and natural sources. [ABSTRACT FROM AUTHOR]

Abstract: Accelerator mass spectrometry (AMS) is presently the most sensitive technique for the measurement of long-lived actinides, e.g. 236U and 239Pu. A new actinide line is in operation at the Center for Isotopic Research on Cultural and Environmental heritage (CIRCE) in Caserta, Italy. Using the actinide line a uranium mass sensitivity of around 4μg has been reached measuring with a 16-strip silicon detector, and a 239Pu background level of below 0.1fg has been obtained. In this work we also discuss preliminary results for environmental and structural samples from in and around the Garigliano nuclear power plant (GNPP), presently in the decommissioning phase. Measurements on environmental samples from the vicinity of the plant allow the assessment of contamination, if any, over the years. Measurements of structural samples from the plant are relevant to the optimization of the decommissioning program for the GNPP. [Copyright &y& Elsevier]

The basement membrane (BM) is a layer of specialized extracellular matrix that surrounds normal prostate glands and preserves tissue integrity. Lack or discontinuity of the BM is a prerequisite for tumor cell invasion into interstitial spaces, thus favoring metastasis. Therefore, BM maintenance represents a barrier against cancer development and progression. In the study, we show that miR-205 participates in a network involving ΔNp63α, which is essential for maintenance of the BM in prostate epithelium. At the molecular level, ΔNp63α is able to enhance miR-205 transcription by binding to its promoter, whereas the microRNA can post-transcriptionally limit the amount of ΔNp63α protein, mostly by affecting ΔNp63α proteasomal degradation rather than through a canonical miRNA/target interaction. Functionally, miR-205 is able to control the deposition of laminin-332 and its receptor integrin-β4. Hence, pathological loss of miR-205, as widely observed in prostate cancer, may favor tumorigenesis by creating discontinuities in the BM. Here we demonstrate that therapeutic replacement of miR-205 in prostate cancer (PCa) cells can restore BM deposition and 3D organization into normal-like acinar structures, thus hampering cancer progression. [ABSTRACT FROM AUTHOR]

Abstract: The reaction plays a key role for the understanding of the production of 7Li in Big Bang nucleosynthesis as well as for the high energy component of the solar neutrino spectrum. The uncertainty in its absolute cross-section arises from systematic differences of the available data sets. In various experiments the cross-section was measured by the detection of the prompt -rays or by the off-line observation of the -rays following the 7Be electron capture; in a few cases both observations were carried out. We report on a new approach based on the use of the recoil separator ERNA (European Recoil separator for Nuclear Astrophysics) to detect directly the 7Be recoils as well as the prompt -rays in coincidence with the recoils. We present technical details of the experimental setup, such as a recirculating 3He gas target, a TOF-E end detector, and a NaI detector array. In addition, the measurement of the separator acceptance is discussed and compared to the expected recoil emittance. The feasibility of the approach is demonstrated by sample spectra, indicating cross-section determinations of in the energy range with high precision and accuracy. [Copyright &y& Elsevier]

Basecalling is an essential step in nanopore sequencing analysis where the raw signals of nanopore sequencers are converted into nucleotide sequences, that is, reads. State-of-the-art basecallers use complex deep learning models to achieve high basecalling accuracy. This makes basecalling computationally inefficient and memory-hungry, bottlenecking the entire genome analysis pipeline. However, for many applications, most reads do not match the reference genome of interest (i.e., target reference) and thus are discarded in later steps in the genomics pipeline, wasting the basecalling computation. To overcome this issue, we propose TargetCall, the first pre-basecalling filter to eliminate the wasted computation in basecalling. TargetCall's key idea is to discard reads that will not match the target reference (i.e., off-target reads) prior to basecalling. TargetCall consists of two main components: (1) LightCall, a lightweight neural network basecaller that produces noisy reads, and (2) Similarity Check, which labels each of these noisy reads as on-target or off-target by matching them to the target reference. Our thorough experimental evaluations show that TargetCall 1) improves the end-to-end basecalling runtime performance of the state-of-the-art basecaller by 3.31 × while maintaining high (98.88 %) recall in keeping on-target reads, 2) maintains high accuracy in downstream analysis, and 3) achieves better runtime performance, throughput, recall, precision, and generality than prior works. TargetCall is available at https://github.com/CMU-SAFARI/TargetCall. [ABSTRACT FROM AUTHOR]

Accurate measurement of bedload is challenging, considering its spatial and temporal variability. Various indirect acoustic techniques are often used for estimating the bedload rate and total bedload mass. Estimating the grain size distribution for a bedload event of relatively short duration, taking the smaller bedload particles into account, is difficult. In the current study, an impact plate with two sensors, namely, an accelerometer and a geophone, is tested in a laboratory flume. Available bedload grains are sorted into different grain size classes, and two sets of experiments are conducted. Single-grain/multigrain particles and mixed-grain particles are considered in the single-class and multiclass experiments, respectively. Three different grain mixtures with variable fineness are fed to the plate in the mixed-grain experiment. The present setup can detect bedload grains from 2.36 to about 150 mm, which is an improvement over other indirect methods. A hybrid analysis methodology to predict the grain size distribution using signals from both sensors is developed. The grain size distributions (GSDs) are estimated with a maximum deviation of 22%, which is expected to improve further with data from longer bedload events. [ABSTRACT FROM AUTHOR]

Simple Summary: Feline infectious peritonitis (FIP) is a severe and even fatal inflammatory disease of cats, caused by feline coronavirus (FCoV), and remains an important diagnostic challenge. This study validates the flow cytometry-based delta total nucleated cells (∆TNC) on the Sysmex XN-1000V® in effusion samples and introduces the FIP Effusion Index, a novel diagnostic method that integrates cellular and inflammatory markers of FIP in effusions. The FIP Effusion Index demonstrated improved diagnostic accuracy, achieving 96.3% sensitivity and 95.7% specificity for values of 5.06 or higher, and perfect specificity (100%) with 96.3% sensitivity at values of 7.54 or above. This combined approach outperforms traditional methods, providing a superior, rapid, and cost-effective tool for the accurate and timely FIP diagnosis. It offers considerable potential for enhancing the management of suspected FIP cases in clinical practice, with potential applications in both veterinary and human medicine for related coronavirus diseases. The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led the medical and scientific community to explore the pathogenesis and clinical manifestations of coronaviruses. In felines, a widespread coronavirus known as feline coronavirus (FCoV) can lead to feline infectious peritonitis (FIP), a highly fatal disease characterised by severe systemic inflammation. Diagnosing FCoV remains challenging due to the limited accuracy of the available methods. The present study introduces the FIP Effusion Index, a novel diagnostic method that combines the albumin-to-globulin (ALB/GLOB) ratio with the delta total nucleated cell (∆TNC) count obtained via flow cytometry using the Sysmex XN-1000V® analyser in effusions. Samples from cats (n = 50) with suspected FIP were analysed for ∆TNC, with findings showing that a ∆TNC ≥ 2.1 is highly indicative of FIP and a ∆TNC ≥ 4.9 can be considered diagnostic. The FIP Effusion Index enhanced diagnostic precision in our group of samples, achieving 96.3% sensitivity and 95.7% specificity for values ≥ 5.06, and reaching perfect specificity (100%) with 96.3% sensitivity for values ≥ 7.54. This combined approach surpasses the accuracy of individual parameters, establishing the FIP Effusion Index as a superior diagnostic tool for FIP, with potential applications in both veterinary and human medicine for related coronavirus diseases. [ABSTRACT FROM AUTHOR]