Electron Glass Phase with Resilient Zhang-Rice Singlets in LiCu_{3}O_{3}.

LiCu_{3}O_{3} is an antiferromagnetic mixed valence cuprate where trilayers of edge-sharing Cu(II)O (3d^{9}) are sandwiched in between planes of Cu(I) (3d^{10}) ions, with Li stochastically substituting Cu(II). Angle-resolved photoemission spectroscopy (ARPES) and density functional theory reveal two insulating electronic subsystems that are segregated in spite of sharing common oxygen atoms: a Cu d_{z^{2}}/O p_{z} derived valence band (VB) dispersing on the Cu(I) plane, and a Cu 3d_{x^{2}-y^{2}}/O 2p_{x,y} derived Zhang-Rice singlet (ZRS) band dispersing on the Cu(II)O planes. First-principle analysis shows the Li substitution to stabilize the insulating ground state, but only if antiferromagnetic correlations are present.

Hyperbolic matter in electrical circuits with tunable complex phases.

Curved spaces play a fundamental role in many areas of modern physics, from cosmological length scales to subatomic structures related to quantum information and quantum gravity. In tabletop experiments, negatively curved spaces can be simulated with hyperbolic lattices. Here we introduce and experimentally realize hyperbolic matter as a paradigm for topological states through topolectrical circuit networks relying on a complex-phase circuit element.

Topological Defect Engineering and PT Symmetry in Non-Hermitian Electrical Circuits.

We employ electric circuit networks to study topological states of matter in non-Hermitian systems enriched by parity-time symmetry PT and chiral symmetry anti-PT (APT). The topological structure manifests itself in the complex admittance bands which yields excellent measurability and signal to noise ratio. We analyze the impact of PT-symmetric gain and loss on localized edge and defect states in a non-Hermitian Su-Schrieffer-Heeger (SSH) circuit.

Association between antimicrobial treatment of subclinical pneumonia in foals and selection of macrolide- and rifampicin-resistant strains at horse-breeding farms in central Kentucky.

Objective: To compare soil concentrations of macrolide- and rifampicin-resistant strains (MRRE) on horse-breeding farms that used thoracic ultrasonographic screening (TUS) to identify foals with subclinical pneumonia combined with subsequent administration of macrolides and rifampin to affected foals (TUS farms) versus soil concentrations on farms that did not (non-TUS farms), determine whether the combined use of TUS and antimicrobial treatment of subclinically affected foals was associated with soil concentration of MRRE, and assess whether there were temporal effects on soil concentrations of MRRE during the foaling season.

Samples: 720 soil samples and 20 completed questionnaires from 20 horse-breeding farms (10 TUS farms and 10 non-TUS farms) in central Kentucky.

Procedures: A questionnaire was used to gather information from participating farms about their 2019 foaling season.

Staff dose evaluation by application of radiation protection during endoscopic retrograde cholangiopancreatography (ERCP) procedures performed with a mobile C-arm.

Background: The radiation dose to staff performing endoscopic retrograde cholangiopancreatography (ERCP) is not negligible.

Purpose: To evaluate the shielding effect of a table-suspended lower-body radiation shield for the positions in the room occupied by the operator, assisting nurse, and anesthesiologist, used during ERCP procedures with a mobile C-arm.

Material And Methods: Eye lens dose, whole body dose, and extremity dose were measured with and without a table-suspended lower-body radiation shield in a phantom model and in clinical routine work.

Imaging nodal knots in momentum space through topolectrical circuits.

Knots are intricate structures that cannot be unambiguously distinguished with any single topological invariant. Momentum space knots, in particular, have been elusive due to their requisite finely tuned long-ranged hoppings. Even if constructed, probing their intricate linkages and topological "drumhead" surface states will be challenging due to the high precision needed.

Turbulent hydrodynamics in strongly correlated Kagome metals.

A current challenge in condensed matter physics is the realization of strongly correlated, viscous electron fluids. These fluids can be described by holography, that is, by mapping them onto a weakly curved gravitational theory via gauge/gravity duality. The canonical system considered for realizations has been graphene.

The novel and transferable erm(51) gene confers macrolides, lincosamides and streptogramins B (MLS ) resistance to clonal Rhodococcus equi in the environment.

The use of mass antimicrobial treatment has been linked to the emergence of antimicrobial resistance in human and animal pathogens. Using whole-genome single-molecule real-time (SMRT) sequencing, we characterized genomic variability of multidrug-resistant Rhodococcus equi isolated from soil samples from 100 farms endemic for R. equi infections in Kentucky.

Topological funneling of light.

Dissipation is a general feature of non-Hermitian systems. But rather than being an unavoidable nuisance, non-Hermiticity can be precisely controlled and hence used for sophisticated applications, such as optical sensors with enhanced sensitivity. In our work, we implement a non-Hermitian photonic mesh lattice by tailoring the anisotropy of the nearest-neighbor coupling.

ISO 4037:2019 VALIDATION OF RADIATION QUALITIES BY MEANS OF HALF-VALUE LAYER AND HP(10) DOSIMETRY.

Radiation qualities were characterised and validated at the fully automated X-ray calibration facility of the Individual Monitoring Service at Helmholtz Zentrum München by using half-value layer and Hp(10) dosimetry approaches specified in the updated ISO 4037:2019 standard. As the ISO 4037 contains a somewhat vague description of the half-value layer procedure, we extended it to be more constrained and thus less subjective in its implementation. We specify both the measurement and data analysis steps performed in order to provide reproducible half-value layer results and compare the results with the Hp(10) dosimetry-based validation approach specified in the ISO 4037 as an alternative for field validation.

Chiral Voltage Propagation and Calibration in a Topolectrical Chern Circuit.

We propose an electric circuit array with topologically protected unidirectional voltage modes at its boundary. Instead of external bias fields or Floquet engineering, we employ negative impedance converters with current inversion (INICs) to accomplish a nonreciprocal, time-reversal symmetry-broken electronic network we call a topolectrical Chern circuit (TCC). The TCC features an admittance bulk gap fully tunable via the resistors used in the INICs, along with a chiral voltage boundary mode reminiscent of the Berry flux monopole present in the admittance band structure.

Identification of macrolide- and rifampicin-resistant Rhodococcus equi in environmental samples from equine breeding farms in central Kentucky during 2018.

Rhodococcus equi causes severe pneumonia in foals and is most often recognized in people as an opportunistic pathogen. Longitudinal studies examining antimicrobial-resistant R. equi from environmental samples are lacking.

SIMULATION OF OSL AND TLD DOSEMETER RESPONSE FOR THE DEVELOPMENT OF NEW EXTREMITY DOSEMETERS.

The individual monitoring service at the Helmholtz Zentrum München is currently developing a new eye lens dosemeter to be integrated in radiation protection glasses and a new ring dosemeter using a new BeOSL detector element for extremity dosimetry developed by Dosimetrics. In the design process for the new eye lens dosemeter, MCNP6 Monte Carlo simulations were used to model the energy and angular response of new dosemeters before ordering the expensive tools for injection molding. This study describes the simulation of the dosemeter and detector, and the involved calculations do obtain the response in terms of the radiation protection quantity Hp(3).

A FULLY AUTOMATED SECONDARY STANDARD X-RAY CALIBRATION FACILITY FOR PERSONAL DOSEMETERS.

The individual monitoring service at the Helmholtz Zentrum München has extended the calibration facilities provided at the Munich IAEA/WHO secondary standard dosimetry laboratory with a new fully automated X-ray calibration facility for the calibration of personal dosemeters according to the ISO 4037 standard series. This work describes the X-ray irradiation system and the automated dosemeter transport system as well as the measurements performed to characterize the photon fields and to ascertain conformity to the ISO standard. Standard uncertainties of the radiation quantities provided by the system are given together with a discussion of some of the problems that are encountered in fulfilling the requirements of a matched field according to the latest drafts of the ISO 4037-1 standard.

Lifetime study in mice after acute low-dose ionizing radiation: a multifactorial study with special focus on cataract risk.

Because of the increasing application of ionizing radiation in medicine, quantitative data on effects of low-dose radiation are needed to optimize radiation protection, particularly with respect to cataract development. Using mice as mammalian animal model, we applied a single dose of 0, 0.063, 0.

Anthropomorphic dual-lattice voxel models for optimizing image quality and dose.

Using numerical simulations, the influence of various imaging parameters on the resulting image can be determined for various imaging technologies. To achieve this, visualization of fine tissue structures needed to evaluate the image quality with different radiation quality and dose is essential. The present work examines a method that employs simulations of the imaging process using Monte Carlo methods and a combination of a standard and higher resolution voxel models.

Robust spin-polarized midgap states at step edges of topological crystalline insulators.

Topological crystalline insulators are materials in which the crystalline symmetry leads to topologically protected surface states with a chiral spin texture, rendering them potential candidates for spintronics applications. Using scanning tunneling spectroscopy, we uncover the existence of one-dimensional (1D) midgap states at odd-atomic surface step edges of the three-dimensional topological crystalline insulator (Pb,Sn)Se. A minimal toy model and realistic tight-binding calculations identify them as spin-polarized flat bands connecting two Dirac points.

SECONDARY STANDARD CALIBRATION, MEASUREMENT AND IRRADIATION CAPABILITIES OF THE INDIVIDUAL MONITORING SERVICE AT THE HELMHOLTZ ZENTRUM MÜNCHEN: ASPECTS OF UNCERTAINTY AND AUTOMATION.

The individual monitoring service at the Helmholtz Zentrum München has adopted the recommendations of the ISO 4037 and 6980 standards series as base of its dosimetric systems for X-ray, gamma and beta dosimetry. These standards define technical requirements for radiation spectra and measurement processes, but leave flexibility in the implementation of irradiations as well as in the resulting uncertainty in dose or dose rate. This article provides an example for their practical implementation in the Munich IAEA/WHO secondary standard dosimetry laboratory.

Interacting Surface States of Three-Dimensional Topological Insulators.

We numerically investigate the surface states of a strong topological insulator in the presence of strong electron-electron interactions. We choose a spherical topological insulator geometry to make the surface amenable to a finite size analysis. The single-particle problem maps to that of Landau orbitals on the sphere with a magnetic monopole at the center that has unit strength and opposite sign for electrons with opposite spin.

Momentum-space entanglement spectrum of bosons and fermions with interactions.

We study the momentum space entanglement spectra of bosonic and fermionic formulations of the spin-1/2 XXZ chain with analytical methods and exact diagonalization. We investigate the behavior of the entanglement gaps, present in both formulations, across quantum phase transitions in the XXZ chain. In both cases, finite size scaling suggests that the entanglement gap closure does not occur at the physical transition points.