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For high precision measurements of K decays, the presence of radiated photons cannot be neglected. The Monte Carlo simulations must include the radiative corrections in order to compute the correct event counting and for efficiency calculations. In this paper, a method for simulating such decays is briefly described.

Background:Reduced availability of tetrahydrobiopterin (BH4), an essential cofactor of nitric oxide (NO) synthase (NOS), decreases NO production and increases reactive oxygen species. Both mechanisms contribute to atherosclerotic vascular disease. Although acute supplementation of BH4 improves endothelial dysfunction, the effect of chronic BH4 in humans is unknown.Objective:To investigate the effect of chronic BH4 supplementation on endothelial function and oxidative stress in hypercholesterolaemia.Design:Randomised double-blind, placebo-controlled trial.Setting:University Hospital.Patients:22 hypercholesterolaemic patients (low-density lipoprotein (LDL) >4.5 mmol/l) were randomised to 4 weeks of oral BH4 (400 mg twice daily) or placebo. Age-matched healthy volunteers served as controls.Main outcome measures:Endothelium-dependent and -independent vasodilatation was assessed by venous occlusion plethysmography. To elucidate the mechanisms of BH4 effect, NO release and superoxide anion (O2−) production were measured in human aortic endothelial cells exposed to native LDL (2.6 mmol cholesterol/l).Results:BH4 plasma levels were significantly increased by oral supplementation. NO-mediated vasodilatation to acetylcholine was reduced in patients compared with controls and restored by BH4. No effect of BH4 on endothelium-independent vasodilatation was seen. Furthermore, 8-F2 isoprostane plasma levels, a marker of vascular oxidative stress, were reduced by BH4. In LDL-treated endothelial cells, BH4 levels and NO release were reduced and O2− production increased compared with control cells. Exogenous BH4 normalised NO and O2− production.Conclusions:In hypercholesterolaemia, endothelial dysfunction and oxidative stress can be reversed by chronic oral treatment with BH4. Thus, BH4 availability is essential for maintaining NO synthesis and low O2− production by endothelial NOS in vivo, and may provide a rational therapeutic approach to prevent cardiovascular disease.

Backgroundγ9δ2 T cells hold great promise as cancer therapeutics because of their unique capability of reacting to metabolic changes with tumor cells. However, it has proven very difficult to translate this promise into clinical success.MethodsIn order to better utilize the tumor reactivity of γ9δ2T cells and combine this with the great potential of T cell engager molecules, we developed a novel bispecific molecule by linking the extracellular domains of tumor-reactive γ9δ2TCRs to a CD3-binding moiety, creating gamma delta TCR anti-CD3 bispecific molecules (GABs). GABs were tested in vitro and in vivo for ability to redirect T lymphocytes to a variety of tumor cell lines and primary patient material.ResultsGABs utilizing naturally occurring high affinity γ9δ2TCRs efficiently induced αβT cell mediated phosphoantigen-dependent recognition of tumor cells. Reactivity was substantially modulated by variations in the Vδ2 CDR3-region and the BTN2A1-binding HV4-region between CDR2 and CDR3 of the γ-chain was crucial for functionality. GABs redirected αβT cells against a broad range of hematopoietic and solid tumor cell lines and primary acute myeloid leukemia. Furthermore, they enhanced infiltration of immune cells in a 3D bone marrow niche and left healthy tissues intact, while eradicating primary multiple myeloma cells. Lastly, GABs constructed from natural high affinity γ9δ2TCR sequences significantly reduced tumor growth in vivo in a subcutaneous myeloma xenograft model.ConclusionsWe conclude that GABs allow for the introduction of metabolic targeting of cancer cells to the field of T cell engagers.

Reducing noise to the quantum limit over a large bandwidth is a fundamental requirement for future applications operating at millikelvin temperatures, such as the neutrino mass measurement, the next-generation X-ray observatory, the CMB measurement, the dark matter and axion detection, and the rapid high-fidelity readout of superconducting qubits. The read out sensitivity of arrays of microcalorimeter detectors, resonant axion-detectors, and qubits, is currently limited by the noise temperature and bandwidth of the cryogenic amplifiers. The Detector Array Readout with Traveling Wave Amplifiers project has the goal of developing high-performing innovative traveling wave parametric amplifiers with a high gain, a high saturation power, and a quantum-limited or nearly quantum-limited noise. The practical development follows two different promising approaches, one based on the Josephson junctions and the other one based on the kinetic inductance of a high-resistivity superconductor. In this contribution, we present the aims of the project, the adopted design solutions and preliminary results from simulations and measurements.

Superconducting parametric amplifiers offer the capability to amplify feeble signals with extremely low levels of added noise, potentially reaching quantum-limited amplification. This characteristic makes them essential components in the realm of high-fidelity quantum computing and serves to propel advancements in the field of quantum sensing. In particular, Traveling-Wave Parametric Amplifiers (TWPAs) may be especially suitable for practical applications due to their multi-Gigahertz amplification bandwidth, a feature lacking in Josephson Parametric Amplifiers (JPAs), despite the latter being a more established technology. This paper presents recent developments of the DARTWARS (Detector Array Readout with Traveling Wave AmplifieRS) project, focusing on the latest prototypes of Kinetic Inductance TWPAs (KITWPAs). The project aims to develop a KITWPA capable of achieving 20 dB of amplification. To enhance the production yield, the first prototypes were fabricated with half the length and expected gain of the final device. In this paper, we present the results of the characterization of one of the half-length prototypes. The measurements revealed an average amplification of approximately 9 dB across a 2 GHz bandwidth for a KITWPA spanning 17 mm in length.

The Italian institute for nuclear physics (INFN) has financed the SIMP project (2019–2021) in order to strengthen its skills and technologies in the field of meV detectors with the ultimate aim of developing a single microwave photon detector. This goal will be pursued by improving the sensitivity and the dark-count rate of two types of photodetectors: current-biased Josephson junction (CBJJ) for the frequency range 10–50 GHz and transition-edge sensor (TES) for the frequency range 30–100 GHz. Preliminary results on materials and devices characterization are presented.

This work presents a study of the impact of the linearity assumption of the mechanical model in the overall performance of an energy harvesting piezoelectric beam. Also, a brief assessment of geometrical optimization solutions using different objective functions is presented. The mechanical model of the harvester is based on both linear and nonlinear variants of the electrical and mechanical constitutive equations for the piezoelectric material. The nonlinear elastic, damping and electromechanical coupling parameters are obtained via least squares identification using physical experimentation; the experimental tests are performed at different ground excitation accelerations. The computational optimization of the harvester is done using the genetic algorithm implemented in Matlab. Different objective functions are tested, i.e. broadband maximum peak power, maximum power at a particular frequency and broadband mean power; the influence of the selection of each of them in the total recovery of the power of the device is analyzed. The most suitable function to recover the vibratory energy from conventional transport vehicles is found.

This paper presents the influence of nonlinear terms of a previously proposed constitutive piezoelectric equation on the dynamics of a cantilever aluminium beam with a piezoelectric unimorph PZT (MIDE QP16N) attached to it. The system is subjected to different levels of base acceleration with the intention to evidence the limits of the linear model. To carry out the analysis, a one-dimensional model is applied and solved employing a single-term solution of the harmonic balance method to compare with the experiments. A model identification of linear and nonlinear parameters such as dissipation, stiffness, and electromechanical coupling were then performed. From the results, it is possible to observe the departure of the linear model even for very low acceleration levels (0.1G). It can be concluded that the nonlinearity plays an unavoidable roll in predicting electric generation for the considered systems.