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Context: In the realm of quantum chemistry, the accurate prediction of electronic structure and properties of nanostructures remains a formidable challenge. Density functional theory (DFT) and density matrix renormalization group (DMRG) have emerged as two powerful computational methods for addressing electronic correlation effects in diverse molecular systems. We compare ground-state energies ( e 0 ), density profiles ( n ), and average entanglement entropies ( S ¯ ) in metals, insulators and at the transition from metal to insulator, in homogeneous, superlattices, and harmonically confined chains described by the fermionic one-dimensional Hubbard model. While for the homogeneous systems, there is a clear hierarchy between the deviations, D % ( S ¯ ) < D % ( e 0 ) < D ¯ % ( n ) , and all the deviations decrease with the chain size; for superlattices and harmonic confinement, the relation among the deviations is less trivial and strongly dependent on the superlattice structure and the confinement strength considered. For the superlattices, in general, increasing the number of impurities in the unit cell represents lower precision in the DFT calculations. For the confined chains, DFT performs better for metallic phases, while the highest deviations appear for the Mott and band-insulator phases. This work provides a comprehensive comparative analysis of these methodologies, shedding light on their respective strengths, limitations, and applications., Methods: The DFT calculations were performed using the standard Kohn-Sham scheme within the BALDA approach. It integrated the numerical Bethe-Ansatz (BA) solution of the Hubbard model as the homogeneous density functional within a local-density approximation (LDA) for the exchange-correlation energy. The DMRG algorithms were implemented using the ITensor library, which is based on the matrix product states (MPS) ansatz. The calculations were performed until the energy reaches convergence of at least 10 - 8 ., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Objectives: To determine the prevalence of the medial depression of mandibular ramus (MDMR) in dry human mandibles and in clinical panoramic radiographs and to compare the prevalence in dentoskeletal deformities with Angle Class I occlusion., Methods: Two hundred and fifty-one dry skulls and three groups of patients were used for this study: Group 1 consisted of 1358 panoramic radiographs from a general population, Group 2, 426 radiographs from individuals with Angle class I occlusion and Group 3283 individuals with dentoskeletal deformities. The prevalence of MDMR was determined in the skulls and each group and the shape from the radiographs alone., Results: The prevalence of MDMR in dry mandibles was 33.9% (bilateral in 13.1% and unilateral in 20.8%). MDMR was found in 276 radiographs (20.3% - Group 1 - bilateral in 40% and unilateral in 59.5%). MDMR was more common in Group 3 compared with Group 2 (chi(2)=35.98 P<0.01). A triangular MDMR was the most frequent (39.7%)., Conclusion: MDMR is a relatively common finding in panoramic radiographs. Patients with dentoskeletal deformities have a higher prevalence of MDMR and this should be taken into consideration if orthognathic surgery is proposed.

Three Paracoccidioides brasiliensis antigens, namely a culture filtrate preparation, a somatic antigen and a mixture of equal parts of the two, were tested by two serological techniques against sera from patients with paracoccidioidomycosis, and in an in vivo delayed hypersensitivity model in mice. The antigen mixture was more sensitive than the two individual antigens for the evaluation of the humoral and cellular immune response to P. brasiliensis, both in man and in experimental animals.