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Conventional classical confidence intervals in specific cases are unphysical. A solution to this problem has recently been published by Feldman and Cousins. We show that there are cases where the new approach is not applicable and that it does not remove the basic deficiencies of classical confidence limits.

Inclusive differential cross sections $d\\sigma_{pA}/dx_F$ and $d\\sigma_{pA}/dp_t^2$ for the production of \\kzeros, \\lambdazero, and \\antilambda particles are measured at HERA in proton-induced reactions on C, Al, Ti, and W targets. The incident beam energy is 920 GeV, corresponding to $\\sqrt {s} = 41.6$ GeV in the proton-nucleon system. The ratios of differential cross sections \\rklpa and \\rllpa are measured to be $6.2\\pm 0.5$ and $0.66\\pm 0.07$, respectively, for \\xf $\\approx-0.06$. No significant dependence upon the target material is observed. Within errors, the slopes of the transverse momentum distributions $d\\sigma_{pA}/dp_t^2$ also show no significant dependence upon the target material. The dependence of the extrapolated total cross sections $\\sigma_{pA}$ on the atomic mass $A$ of the target material is discussed, and the deduced cross sections per nucleon $\\sigma_{pN}$ are compared with results obtained at other energies.

SARS-CoV-2 is a respiratory pathogen and primarily infects the airway epithelium. As our knowledge about innate immune factors of the respiratory tract against SARS-CoV-2 is limited, we generated and screened a peptide/protein library derived from bronchoalveolar lavage for inhibitors of SARS-CoV-2 spike-driven entry. Analysis of antiviral fractions revealed the presence of α 1 -antitrypsin (α 1 AT), a highly abundant circulating serine protease inhibitor. Here, we report that α 1 AT inhibits SARS-CoV-2 entry at physiological concentrations and suppresses viral replication in cell lines and primary cells including human airway epithelial cultures. We further demonstrate that α 1 AT binds and inactivates the serine protease TMPRSS2, which enzymatically primes the SARS-CoV-2 spike protein for membrane fusion. Thus, the acute phase protein α 1 AT is an inhibitor of TMPRSS2 and SARS-CoV-2 entry, and may play an important role in the innate immune defense against the novel coronavirus. Our findings suggest that repurposing of α 1 AT-containing drugs has prospects for the therapy of COVID-19. Here, via screening of a polypeptide library from bronchoalveolar lavage, the authors identify and characterize α 1 -antitrypsin (α 1 AT) as SARS-CoV-2 inhibitor and show that α 1 AT binds and inactivates the serine protease TMPRSS2, which enzymatically primes the SARS-CoV-2 spike protein for membrane fusion.

In general we are interested in dynamical systems coupled to complex hysteresis. Therefore as a first step we investigated recently the dynamics of a periodically driven damped harmonic oscillator coupled to independent Ising spins in a random field. Although such a system does not produce hysteresis, we showed how to characterize the dynamics of such a piecewise-smooth system, especially in the case of a large number of spins [P. Zech, A. Otto, and G. Radons, Phys. Rev. E 101, 042217 (2020)]. In this paper we extend our model to spin dimers, thus pairwise interacting spins. We show in which cases two interacting spins can show elementary hysteresis and we give a connection to the Preisach model, which allows us to consider an infinite number of spin-pairs. This thermodynamic limit leads us to a dynamical system with an additional hysteretic force in the form of a generalized play operator. By using methods from general chaos theory, piecewise-smooth system theory and statistics we investigate the chaotic behavior of the dynamical system for a few spins and also in case of a larger number of spins by calculating bifurcation diagrams, Lyapunov exponents, fractal dimensions and self-averaging properties. We find that the fractal dimensions and the magnetization are in general not self-averaging quantities. We show, how the dynamical properties of the piecewise-smooth system for a large number of spins differs from the system in its thermodynamic limit.

We aim at an understanding of the dynamical properties of a periodically driven damped harmonic oscillator coupled to a Random Field Ising Model (RFIM) at zero temperature, which is capable to show complex hysteresis. The system is a combination of a continuous (harmonic oscillator) and a discrete (RFIM) subsystem, which classifies it as a hybrid system. In this paper we focus on the hybrid nature of the system and consider only independent spins in quenched random local fields, which can already lead to complex dynamics such as chaos and multistability. We study the dynamic behavior of this system by using the theory of piecewise-smooth dynamical systems and discontinuity mappings. Specifically, we present bifurcation diagrams, Lyapunov exponents as well as results for the shape and the dimensions of the attractors and the self-averaging behavior of the attractor dimensions and the magnetization. Furthermore we investigate the dynamical behavior of the system for an increasing number of spins and the transition to the thermodynamic limit, where the system behaves like a driven harmonic oscillator with an additional nonlinear smooth external force.

For the effective use of mulch materials in tropical agriculture and agroforestry knowledge of the speed of decomposition and nutrient release is of primary importance. The transfer of these informations from one site to another requires comparability of the processes of decomposition and their intensity at the two sites. In a litterbag experiment the decomposition and release of main nutrients from leaves and branches of Cajanus cajan (L.) Millsp. were investigated with regard to the underlying physical and biological processes during an 81 days period. To test the influence of perennial plants on the decomposition process, the study was conducted on an agricultural field in 1.1m, 6.9 m and 14.9 m distance from a tree and hedge band. During the first 11 days leaching was high, especially for N and P (about 50% lost) and K (75-80% lost). After the 11th day consumption of the mulch material by the soil fauna was the dominating process of decomposition. During this phase the perennial plants significantly retarded the decomposition of Cajanus branches, but not leaves, probably by their influence on termite activity. Ca release was also retarded in leaves. After about 6-7 weeks, more than 90% of all main nutrients except Ca had been released from the samples. To minimize nutrient losses from nutrient-rich mulch materials, they should be applied repeatedly in small quantities according to the nutrient demand of the crop.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) causes coronavirus disease 2019 (COVID-19). To identify factors of the respiratory tract that suppress SARS-CoV-2, we screened a peptide/protein library derived from bronchoalveolar lavage, and identified α1-antitrypsin (α1-AT) as specific inhibitor of SARS-CoV-2. α1-AT targets the viral spike protein and blocks SARS-CoV-2 infection of human airway epithelium at physiological concentrations. Our findings show that endogenous α1-AT restricts SARS-CoV-2 and repurposes α1-AT-based drugs for COVID-19 therapy.