Spectrum shape measurements in nuclear \(\beta\) decay can be used to test physics beyond the Standard Model with results being complementary to high-energy collider experiments. In particular, ...Beyond Standard Model sensitivity of the weak interaction is expressed through the so-called Fierz interference term. Additionally, the \(\beta\) spectrum shape is a useful tool to probe Standard Model effects, among which the most prominent is \textit{weak magnetism}, a higher-order recoil correction induced by nuclear pion exchange. To study effects in the \(\beta\) spectrum shape at a precision level competitive with the LHC, a new spectrometer was designed and built. It consists of a 3D low-pressure gas electron tracker and a plastic scintillator used for triggering the data acquisition and recording the \(\beta\) particle energy. In this Letter, the results from \(\beta\) spectrum shape measurements on the allowed Gamow-Teller transition \(^{114}\text{In} \rightarrow ^{114}\text{Sn}\) are presented, including a first extraction of the weak magnetism form factor in the high nuclear mass range and a new estimate of the \(90\%\) confidence interval for the Fierz interference term.
Searches of new physics beyond the Standard Model (SM) performed at low energy frontiers are complementary to experiments carried out at high energy colliders. Among the methods for testing the SM ...and beyond at low energies are the precision spectrum shape and correlation coefficient measurements in nuclear and neutron beta decay. In order to study tiny effects in beta spectrum shape, a special spectrometer was built. It consists of a 3D low pressure gas tracker (drift chamber with hexagonal cells, signal readout at both wire ends) and plastic scintillators for triggering data acquisition and registration of the beta particle energy. The results of the characterization process indicate the possibility of using such a gas tracker in a range of experiments with low energy electrons where beta particle tracking with minimal kinematics deterioration is beneficial. Application of this technique is also planned for neutron decay correlation experiments. In the paper, the first application of this tracker in a high-precision beta spectrum shape study is discussed. The measurement technique, commissioning results, and the future outlook are presented.
Purpose
Herpes simplex virus (HSV) and varicella-zoster virus (VZV) are neurotropic human alphaherpesviruses endemic worldwide. Upon primary infection, both viruses establish lifelong latency in ...neurons and reactivate intermittently to cause a variety of mild to severe diseases. Acute retinal necrosis (ARN) is a rare, sight-threatening eye disease induced by ocular VZV or HSV infection. The virus and host factors involved in ARN pathogenesis remain incompletely described. We hypothesize an underlying genetic defect in at least part of ARN cases.
Methods
We collected blood from 17 patients with HSV-or VZV-induced ARN, isolated DNA and performed Whole Exome Sequencing by Illumina followed by analysis in Varseq with criteria of CADD score > 15 and frequency in GnomAD < 0.1% combined with biological filters. Gene modifications relative to healthy control genomes were filtered according to high quality and read-depth, low frequency, high deleteriousness predictions and biological relevance.
Results
We identified a total of 50 potentially disease-causing genetic variants, including missense, frameshift and splice site variants and on in-frame deletion in 16 of the 17 patients. The vast majority of these genes are involved in innate immunity, followed by adaptive immunity, autophagy, and apoptosis; in several instances variants within a given gene or pathway was identified in several patients.
Discussion
We propose that the identified variants may contribute to insufficient viral control and increased necrosis ocular disease presentation in the patients and serve as a knowledge base and starting point for the development of improved diagnostic, prophylactic, and therapeutic applications.
In the frame of the 1EA-AMF project "Real Impact of New Technologies for Heavy Duty Vehicles", three state-of-the-art city bus technologies were evaluated for fuel consumption and emissions in real ...city traffic and in a number of test cycles, both on engine and on vehicle level. The three buses were a diesel bus, a natural gas bus with stoichiometric fuel control and three-way catalyst, and a natural gas bus with lean burn fuel control. The paper will compare fuel consumption and emissions of the three buses measured in real-city traffic using Vito's VOEM measurement system. The measurements showed that the natural gas buses had clearly higher fuel consumption (in diesel equivalents) than the diesel bus, caused by the lower average engine efficiency.
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