The NIST compilation of ionization potentials revisited (I): From He-like to Xe-like ions

The National Institute of Standards and Technology (NIST) database on ionization potentials for neutral atoms and ions is examined. For each isoelectronic sequence, we construct a regularized perturbative series that exactly matches the large-$Z$ and $Z\approx N-1$ regions. Comparison of the NIST data with this series allows the identification of problematic values in the reported data.Comment: 19 pages, 43 figure

Application of botanicals in poultry production to improve microbiological quality

Foodborne illness and outbreaks associated with poultry products are commonly caused by Campylobacter jejuni or Salmonella enterica. These pathogens colonize the bird intestines during rearing, and if processing, handling or cooking is not done properly, contamination and human illness can occur. Probiotics, prebiotics and botanicals are being evaluated as novel feed additives to reduce pathogen colonization and serve as growth promoter additives in poultry production. Some botanicals are of industrial interest because they are natural antimicrobials or possess beneficial effects on human health. In this research, the application of a botanical (yerba mate) and a probiotic were evaluated as feed additives for broiler chickens to reduce Salmonella colonization. First, the antimicrobial activity of yerba mate extract was evaluated in vitro against Salmonella Enteritidis (SE) and lactic acid bacteria (LAB). Then, in vivo evaluations were conducted. Day-of-hatch chicks were treated with of the following 1) no treatment (control); 2) ground yerba mate in feed; 3) probiotic treatment (Lactobacillus acidophilus and Pediococcus; 9:1 administered once on day-of-hatch by gavage) or 4) both yerba mate and probiotic treatments. At day 3, all chicks were challenged with SE and at day 10, all birds were euthanized and cecal contents enumerated for Salmonella. For the in vitro evaluation, antimicrobial activity was observed against Salmonella, while the same treatment enhanced growth of LAB. For in vivo evaluations, the probiotic treatment significantly reduced Salmonella colonization in the horizontal transmission experiment while none of the yerba mate treatments significantly reduced SE colonization. Yerba mate decreased chicken body weight and decreased the performance of the probiotic treatment when used in combination. It is important to evaluate the use of novel probiotics, prebiotics or botanicals for poultry production. Bird health, growth promoter effects or antinutritional factors of botanicals should be considered before designing diets

Optical photometry of the UCM Lists I and II

We present Johnson B CCD photometry for the whole sample of galaxies of the Universidad Complutense de Madrid (UCM) Survey Lists I and II. They constitute a well-defined and complete sample of galaxies in the Local Universe with active star formation. The data refer to 191 S0 to Irr galaxies at an averaged redshift of 0.027, and complement the already published Gunn r, J and K photometries. In this paper the observational and reduction features are discussed in detail, and the new colour information is combined to search for clues on the properties of the galaxies, mainly by comparing our sample with other surveys.Comment: 14 pages, 7 PostScript figures, accepted for publication in A&AS, also available vi ftp at ftp://cutrex.fis.ucm.es/pub/OUT/pag/PAPERS

Performances of multi-gap timing RPCs for relativistic ions in the range Z=1-6

We present the performance of Multi-gap timing RPCs under irradiation by fully stripped relativistic ions (gamma*beta=2.7, Z=1-6). A time resolution of 80 ps at high efficiency has been obtained by just using standard `off the shelf' 4-gap timing RPCs from the new HADES ToF wall. The resolution worsened to 100 ps for ~ 1 kHz/cm2 proton flux and for ~ 100 Hz/cm2 Carbon flux. The chambers were operated at a standard field of E=100 kV/cm and showed a high stability during the experiment, supporting the fact that RPCs are a convenient choice when accommodating a very broad range of ionizing particles is needed. The data provides insight in the region of very highly ionizing particles (up to x 36 mips) and can be used to constrain the existing avalanche and Space-Charge models far from the usual `mip valley'. The implications of these results for the general case of detection based on secondary processes (n, gamma) resulting in highly ionizing particles with characteristic energy distributions will be discussed, together with the nature of the time-charge correlation curve.Comment: 31 pages, 19 figures, submitted to JINS

PBC design for voltage regulation in buck converters with parametric uncertainties

This paper addresses the problem of voltage output regulation in DC Buck converters from the passivity-based control (PBC) point of view. The PBC takes advantage of the natural port-Hamiltonian representation of dynamic equations of the buck converter, to design a feedback controller with proportionalintegral gains, that allows to guarantee stability conditions in the sense of Lyapunov for closed-loop operation. The design of the controller is based on the incremental dynamic model of the buck converter. The PBC approach considers unknown resistive loads in the controller design without degrading the dynamic performance of the controller. In addition, the proposed approach allows to design a controller regardless the buck parameters (capacitance and inductance) which makes it robust to parametric uncertainties. Sliding planes and classical PI control methods are used for comparing the proposed PBC method. All simulations have been performed in MATLAB software by using SymPowerSystems library

Mitigating fluctuations of wind power generation using superconducting magnetic energy storage: A passivity-based approach

Abstract This paper presents the control of the active and reactive power of a superconducting magnetic energy storage (SMES) system for compensating fluctuations of a power system with high penetration of wind energy during extreme scenarios of wind gusts. The wind energy conversion system (WECS) is a Type-A turbine with squirrel cage induction generator (SCIG) and a capacitor bank. A passivity-based proportional-integral control (PI-PBC) is used that controls the power transfer of the SMES system to the power grid. The proposed controller is designed with two main objectives: First, to deliver (or absorb) a suitable active power to (or from) the power system, and second, to regulate the voltage of the WECS. The proposed PI-PBC guarantees asymptotically stability in closed-loop and exploits the advantages of the proportional-integral (PI) actions. Also, it presents a superior performance when it is compared to a conventional PI controller and a proportional feedback linearization controller. Simulation results carried-out in MATLAB/SIMULINK demonstrate the advantages of the proposed methodology. © 2019 IEEE

Testing linearity for a regression model with imprecise elements: a power analysis

A linearity test for a simple regression model with imprecise random elements is analyzed. The concept of LR fuzzy random variable is used to formalize imprecise random elements. The proposed linearity test is based on the comparison of the simple linear regression model and the nonparametric regression. In details, based on the variability explained by the above two models, the test statistic is constructed. The asymptotic significance level and the power under local alternatives are established. Since large samples are required to obtain suitable asymptotic results a bootstrap approach is investigated. Furthermore, in order to illustrate how the proposed test works in practice, some simulation and real-life examples are given