Universidade Federal da Grande Dourados

Covering schemes were recently introduced as a generalization of both difference matrices and difference schemes, providing an efficient method for building covering arrays with a certain degree of symmetry. On the other hand, Tang and Woo (1983) showed that sets of constant-weight tuples yield several upper bounds on covering arrays. However, these sets usually do not have enough symmetry to induce good covering schemes. In this work, we derive a classification of invariant sets of constant-weight tuples under the action of the diagonal group of ℤ_q^k . This classification enables us to obtain new upper bounds on covering scheme numbers, including the exact class for binary covering scheme numbers with k columns and strength k-2.

Quantum thermometry provides a key capability for nanoscale devices and quantum technologies, but most existing strategies rely on probes initialized near equilibrium. This equilibrium paradigm imposes intrinsic limitations: sensitivity is tied to long-time thermalization and often cannot be improved in fast, noisy, or nonstationary settings. In contrast, the Mpemba effect, the counterintuitive phenomenon where hotter states relax faster than colder ones, has mostly been viewed as a thermodynamic anomaly. Here, we bridge this gap by proving that Mpemba-type inversions generically yield a finite-time enhancement of the quantum Fisher information (QFI) for temperature estimation, thereby converting an anomalous relaxation effect into a concrete metrological resource. Through explicit analyses of two-level and Λ-level probes coupled to bosonic baths, we show that nonequilibrium initializations can transiently outperform both equilibrium strategies and colder states, realizing a metrological Mpemba effect. Our results establish anomalous relaxation as a general design principle for nonequilibrium quantum thermometry, enabling ultrafast and nanoscale sensing protocols that exploit, rather than avoid, transient dynamics.

Leveraging the unique quantum properties of non-Gaussian states is crucial for advancing continuous variable quantum technologies. Recent experimental advancements in generating non-Gaussian states, coupled with theoretical findings of their superior performance in quantum information protocols compared to Gaussian states, motivate this investigation. This work investigates the role of the non-Gaussianity on the frequency estimation problem. The analysis focuses on a single bosonic mode and its non-Gaussian excited states as probe states, while the frequency estimation is investigated by explicitly computing the quantum Fisher information. Firstly, we consider a stationary regime, where the study of single Fock states yields a deeper understanding of the behavior of the non-Gaussianity as well as its comparison with other relevant candidates to probes, such as the coherent and squeezed vacuum states. Here, the connection with the non-Gaussianity is also discussed, as well as the Heisenberg limit and the comparison with other relevant superposition states for the same task. The results indicate that the advantage in using Fock states as probes for frequency estimation is directly associated with the degree of non-Gaussianity of the probe.

Background: Vulvovaginal candidiasis (VVC) is a significant public health concern characterized by increasing incidence and challenges in treatment. However, most studies investigating Candida spp. virulence factors and antifungal susceptibility predominantly rely on in vitro assays. While these assays are highly reproducible, they do not accurately replicate the complex vaginal microenvironment. To address this limitation, we developed an ex vivo model using porcine vaginal mucosa and a physiologically relevant volume of simulated vaginal fluid (SFV) to better mimic human vaginal conditions. Methods: Biofilm formation and fluconazole activity were assessed using the reference strain Candida albicans ATCC 90028 and two clinical isolates associated with VVC. Results were expressed as colony-forming units (CFU) and directly compared with in vitro assays conducted in Sabouraud dextrose broth (SDB) and SVF. Results: CFU analysis revealed that the ex vivo vaginal mucosa model supported more robust biofilm development, with counts ranging from 6.67 & times; 10(7) to 7.20 & times; 10(7) CFU/mL, compared to the in vitro SDB assay (3.58 & times; 10(7) to 4.5 & times; 10(7) CFU/mL). This suggests enhanced fungal growth under tissue-based conditions. Moreover, fluconazole achieved greater biofilm eradication in the ex vivo model (>70%) compared to the in vitro SDB assay (<= 34.50%), which may indicate increased antifungal activity within a physiologically relevant environment. Conclusions: The ex vivo vaginal mucosa model offers a physiologically relevant platform for supporting C. albicans biofilm development and serves as a valuable alternative for preclinical screening of antifungal agents.

We study the scaled transverse momentum spectra over a wide parameter space of state-of-the-art hydrodynamic simulation models in order to learn what information can be obtained from the shape of identified-particle spectra – previously observed to be surprisingly universal across centrality and collision systems in both experimental data and hydrodynamic simulations. We study its sensitivity to each of 17 model parameters in the context of 4 different models for particlization when switching from the hydro description to the kinetic theory afterburner. We find that the strongest sensitivity is to parameters relating to bulk viscosity, free-streaming time, and the nucleon width parameter w. However, we find that the model generally has surprisingly little flexibility in describing the scaled spectrum observable, despite the large number of parameters. Within this small range of parameter dependence, we further find significant tension in a simultaneous description of momentum-integrated observables. In particular, while the mean transverse momentum prefers a large value of the nucleon width parameter w, a small value is required to obtain scaled spectra that are consistent with experimental measurements. We speculate on the origin of these model tensions and possible missing physics in the commonly-used +free streaming+hydro+afterburner simulation model.