Quantum Discord and entropic measures of quantum correlations: Optimization and behavior in finite XYXY spin chains

We discuss a generalization of the conditional entropy and one-way information deficit in quantum systems, based on general entropic forms. The formalism allows to consider simple entropic forms for which a closed evaluation of the associated optimization problem in qudit-qubit systems is shown to become feasible, allowing to approximate that of the quantum discord. As application, we examine quantum correlations of spin pairs in the exact ground state of finite $XY$ spin chains in a magnetic field through the quantum discord and information deficit. While these quantities show a similar behavior, their optimizing measurements exhibit significant differences, which can be understood and predicted through the previous approximations. The remarkable behavior of these quantities in the vicinity of transverse and non-transverse factorizing fields is also discussed.Comment: 10 pages, 3 figure

Financial expert CEOs: Evidence from purchase price allocation

Drawing from the Upper Echelons Theory (UET), this study assesses how firms' accounting outcomes at the transaction level are influenced by the Chief Executive Officer (CEO)'s individual characteristic of financial expertise and managerial status from structural and relational power. We use Purchase Price Allocation (PPA) as a key empirical context, given its technical nature. Utilizing a proprietary dataset that includes information on business combination and key officers' characteristics, we employ multivariate analysis to explore the relationship between the CEO financial expertise and reporting transparency, and the moderating role of the CEO's power. Our findings indicate that firms led by financial expert CEOs are more likely to allocate the purchase price to specific assets. Furthermore, CEOs' structural power enhances the impact of financial expertise on PPA decisions, whereas relational power does not support a similar effect. Robustness checks confirm the validity of our results. This research contributes to the accounting literature by extending UET predictions, highlighting that accounting outcomes are systematically influenced by CEO financial expertise and illustrating how different managerial status within corporate governance affect financial reporting transparency

Characterizing entanglement with global and marginal entropic measures

We qualify the entanglement of arbitrary mixed states of bipartite quantum systems by comparing global and marginal mixednesses quantified by different entropic measures. For systems of two qubits we discriminate the class of maximally entangled states with fixed marginal mixednesses, and determine an analytical upper bound relating the entanglement of formation to the marginal linear entropies. This result partially generalizes to mixed states the quantification of entaglement with marginal mixednesses holding for pure states. We identify a class of entangled states that, for fixed marginals, are globally more mixed than product states when measured by the linear entropy. Such states cannot be discriminated by the majorization criterion.Comment: 6 pages, 5 color figures in low resolution due to oversizing problems; to get the original high-resolution figures please contact the authors. Minor changes, final versio

Variability in public procurement prices for Group 1A drugs in the specialized pharmaceutical component: an observational study, 2013-2022

Objective: To assess the difference in acquisition prices of Group 1A drugs in the Specialized Pharmaceutical Component between purchases made by the Brazilian Ministry of Health and those made by the Paran & aacute; State Health Department. Methods: This was a retrospective observational study comparing prices of medications acquired centrally by the Brazilian Ministry of Health and those acquired by the State of Paran & aacute; to meet court orders or to supply supplementary lists, from 2013 to 2022. The weighted average acquisition price was calculated for each procurement source, per year, based on data from the Paran & aacute; Health Department management information system. The ratio between Paran & aacute;'s and the Brazilian Ministry of Health's weighted average prices was calculated, as well as the hypothetical cost of Paran & aacute;'s purchases had they been made at the Ministry's prices. Total overpricing in Paran & aacute;'s acquisitions was also calculated. Results: A total of 500 price comparisons were conducted, covering 116 different drug presentations. In 84.6% of the comparisons, Paran & aacute;'s prices exceeded those of the Ministry of Health. For seven pharmaceutical presentations, the state price was more than 10 times higher than the federal price, reaching as high as 47.32 times in the most extreme case. Overall, Paran & aacute;'s expenditures exceeded by more than BRL 200 million the amount that would have been paid at the Ministry's prices, resulting in 55.7% overpricing. Conclusion: There was considerable variation between prices of drugs acquired centrally by the Brazilian Ministry of Health and those acquired by the state of Paran & aacute;. To enhance cost-effectiveness within the Brazilian National Health System, mechanisms for centralized price negotiation or procurement should be further explored

Variabilidade de preços de aquisição de medicamentos do grupo 1B do Componente Especializado da Assistência Farmacêutica

Resumo No Sistema Único de Saúde os medicamentos do grupo 1 do Componente Especializado da Assistência Farmacêutica (CEAF) são financiados pela União e adquiridos de forma centralizada (grupo 1A) ou por cada Unidade Federativa (UF) (grupo 1B). Diferentemente de outros países onde se negocia um preço fixo a ser praticado no sistema público, no Brasil as aquisições são realizadas por licitação, o que pode levar a diferentes preços. Para permitir a comparação de preços, foi pactuada a obrigatoriedade de registro das aquisições públicas no Banco de Preços em Saúde (BPS). O estudo teve como objetivo analisar a variabilidade dos preços de medicamentos do grupo 1B adquiridos pelas UF do Brasil em 2021. Foram obtidas as aquisições de medicamentos do grupo 1B realizadas pelas Secretarias de Estado das 27 UF por consulta ao BPS excluindo-se os medicamentos sem preço de ressarcimento estabelecido em dezembro/2021. Foi obtido do Sistema de Informações Ambulatoriais o ressarcimento para cada UF. Verificou-se grande variabilidade dos preços de aquisição para cada medicamento entre as UF e dentro da mesma UF. O estudo demonstrou potencial iniquidade de acesso ao CEAF, privilegiando com menores preços UF mais favorecidas (maior população e riqueza).</jats:p

Transparency, Openness and Knowledge Sharing for Rebuilding and Strengthening Government Institutions

The developing of the Open Government Model is allowing an organizational revolution for public administrations, providing to citizens and entrepreneurs a better access to information and public services. It also can allow the increasing of transparency in public agencies and citizen participation, indirectly enhancing collaboration and facilitating democratic processes. Transparency and open data can be powerful tools to stimulate and support public services’ improvements, faster innovation and empower citizens’ rights. So actually many governmental organizations are reviewing and rearranging their processes, information and data to improve policies, enhance legitimacy and openness toward outside parties and citizens. An “open” public knowledge may contribute to establish a collaboration and participation culture among the main stakeholders. In this paper authors focus on a new organizational model to deliver transparent services and to improve an effective collaboration between the public administrations. The research methodology adopted is based on a theoreticaldeductive approach. The study describes general principles to come, through the case strategy, to the empirical analysis of an innovative national government portal called “Transparency Compass Portal”. It tries also to identify the distinctive aspects of some administrative services offered by several public organizations

History states of one-dimensional quantum walks

We analyze the application of the history state formalism to quantum walks. The formalism allows one to describe the whole walk through a pure quantum history state, which can be derived from a timeless eigenvalue equation. It naturally leads to the notion of system-time entanglement of the walk, which can be considered as a measure of the number of orthogonal states visited in the walk. We then focus on one-dimensional discrete quantum walks, where it is shown that such entanglement is independent of the initial spin orientation for real Hadamard-type quantum coins and real initial states (in the standard basis) with definite site-parity. Moreover, in the case of an initially localized particle it can be identified with the entanglement of the unitary global operator that generates the whole history state, which is related to its entangling power and can be analytically evaluated. Besides, it is shown that the evolution of the spin subsystem can also be described through a spin history state with an extended clock. A connection between its average entanglement (over all initial states) and that of the operator generating this state is also derived. A quantum circuit for generating the quantum walk history state is as well provided.Comment: 12 pages, 7 figure

Knowledge sharing in family SMEs: the role of communities of practice

PurposeThe aim of this paper is to analyse the role of communities of practice (CoP) as knowledge-sharing tools in family small and medium-sized enterprises (SMEs). In this context, CoPs that jointly involve family and non-family members are expected to act as knowledge-sharing tools.Design/methodology/approachThis paper employs a multiple case study methodology, analysing the cases of six small companies in different sectors and countries over a period of 8 years. Both primary and secondary data are used.FindingsThe results show the role CoPs play in involving family and non-family members in empowering knowledge-sharing initiatives. A CoP's role in knowledge sharing depends on the presence (or lack) of a family leader, the leadership approach, the degree of cohesion around shared approaches and values within the CoP, and the presence of multiple generations at work.Originality/valueThis paper contributes to the literature on knowledge sharing in family businesses, by exploring for the first time the role of the CoP as a knowledge-sharing tool, depending on families' involvement in the CoP

The Institute for Religious works: key features of financial intermediation

Corresponding author: F. Arnaboldi, email: [email protected]. While the paper is the result of intense collaboration between the two authors, sections 3 is attributable to F. Arnaboldi and section 1 and 2 to B. Rossignoli. Section 4 is a joint effort. The authors wish to thank P. Mottura and two anonymous referees for their valuable comments. All errors are ours.  Article peer reviewed. SUMMARY: 1. Introduction – 2. Background to anti-money laundering – 3. Financial intermediation, 2011–2014 – 4. Conclusion

Bipartite representations and many-body entanglement of pure states of NN indistinguishable particles

We analyze a general bipartite-like representation of arbitrary pure states of $N$-indistinguishable particles, valid for both bosons and fermions, based on $M$- and $(N-M)$-particle states. It leads to exact $(M,N-M)$ Schmidt-like expansions of the state for any $M<N$ and is directly related to the isospectral reduced $M$- and $(N-M)$-body density matrices $\rho^{(M)}$ and $\rho^{(N-M)}$. The formalism also allows for reduced yet still exact Schmidt-like decompositions associated with blocks of these densities, in systems having a fixed fraction of the particles in some single particle subspace. Monotonicity of the ensuing $M$-body entanglement under a certain set of quantum operations is also discussed. Illustrative examples in fermionic and bosonic systems with pairing correlations are provided, which show that in the presence of dominant eigenvalues in $\rho^{(M)}$, approximations based on a few terms of the pertinent Schmidt expansion can provide a reliable description of the state. The associated one- and two-body entanglement spectrum and entropies are also analyzed.Comment: 17 pages, 5 figure