Symmetric mixed states of nn qubits: local unitary stabilizers and entanglement classes

We classify, up to local unitary equivalence, local unitary stabilizer Lie algebras for symmetric mixed states into six classes. These include the stabilizer types of the Werner states, the GHZ state and its generalizations, and Dicke states. For all but the zero algebra, we classify entanglement types (local unitary equivalence classes) of symmetric mixed states that have those stabilizers. We make use of the identification of symmetric density matrices with polynomials in three variables with real coefficients and apply the representation theory of SO(3) on this space of polynomials.Comment: 10 pages, 1 table, title change and minor clarifications for published versio

Climatização de banana 'prata anã'.

bitstream/item/76024/1/ct49-2002.pd

Mitigating bias in estimating epidemic severity due to heterogeneity of epidemic onset and data aggregation

Outbreaks of infectious diseases, such as influenza, are a major societal burden. Mitigation policies during an outbreak or pandemic are guided by the analysis of data of ongoing or preceding epidemics. The reproduction number, , defined as the expected number of secondary infections arising from a single individual in a population of susceptibles is critical to epidemiology. For typical compartmental models such as the Susceptible-Infected-Recovered (SIR) represents the severity of an epidemic. It is an estimate of the early-stage growth rate of an epidemic and is an important threshold parameter used to gain insights into the spread or decay of an outbreak. Models typically use incidence counts as indicators of cases within a single large population; however, epidemic data are the result of a hierarchical aggregation, where incidence counts from spatially separated monitoring sites (or sub-regions) are pooled and used to infer . Is this aggregation approach valid when the epidemic has different dynamics across the regions monitored? We characterize bias in the estimation of from a merged data set when the epidemics of the sub-regions, used in the merger, exhibit delays in onset. We propose a method to mitigate this bias, and study its efficacy on synthetic data as well as real-world influenza and COVID-19 data

Organizational system thinking as a cognitive framework to meet climate targets

System thinking is a crucial cognitive framework to enable individual pro-environmental behavioral changes. Indeed, a large body of literature has shown a significant and positive association between individuals' system thinking capacities and perceptions of the threat posed by climate change. However, individual behavioral changes play a limited role in addressing climate change compared to large organizations involved in a significantly larger share of economic activities. Do organizations exhibit system thinking capacities? Here, we conjecture that system thinking is a cognitive framework observable at an aggregated group level and, therefore, organizations, not just individuals, can exhibit characteristic levels of system thinking. We conceptualize a definition of organizational system thinking and develop an empirical method to estimate it using a large body of textual data from business organizations. Then, we show that system thinking organizations are more likely to lower emissions and align them with the pathways required to meet the climate targets set by the Paris Agreement. Finally, we discussed the theoretical and policy implication of our study. Overall, our results suggest that system thinking is a relevant organization-level cognitive framework that can help organizations align their emissions with global climate targets

Considerações sobre o ponto de colheita de manga para exportação.

bitstream/item/75991/1/ct54-2002.pd

A large-scale analysis of the heterogeneity of markets' reactions to the disclosure of nonfinancial information

To allocate capital to its most sustainable use, market participants need information on companies' sustainability plans and initiatives. This information is disclosed in sustainability reports, but the disclosure process is largely unregulated and voluntary. When do sustainability reports convey relevant information? To answer this question we estimate the heterogeneous effects of nonfinancial disclosure on analysts' estimates of earnings and firms' equity values. We have found that the information content of nonfinancial disclosure is larger when firms are subject to greater information asymmetry, and when nonfinancial information is integrated within a financial context. Moreover, positive responses have a long-lasting impact while negative shocks are corrected within a short window. Overall, our work suggests that market participants' interest in standalone nonfinancial information is limited, and integrated reporting increases the value of sustainability reports

Manual de perdas pós-colheita em frutos e hortaliças.

Produção e perdas de frutos e hortaliças no Brasil. Perdas: definição, tipos e causas. Alguns aspectos envolvidos no controle das perdas: pré-colheita; colheita; pós-colheita; embalagem; transporte; armazenamento. Aspectos de mercado.bitstream/item/33932/1/1997-DOC-0027.pd

Entanglement classes of symmetric Werner states

The symmetric Werner states for $n$ qubits, important in the study of quantum nonlocality and useful for applications in quantum information, have a surprisingly simple and elegant structure in terms of tensor products of Pauli matrices. Further, each of these states forms a unique local unitary equivalence class, that is, no two of these states are interconvertible by local unitary operations.Comment: 4 pages, 1 table, additional references in version 2, revised abstract and introduction in version 3, small clarifications for published version in version

The Drosophila Citrate Lyase Is Required for Cell Division during Spermatogenesis

The Drosophila melanogaster DmATPCL gene encodes for the human ATP Citrate Lyase (ACL) ortholog, a metabolic enzyme that from citrate generates glucose-derived Acetyl-CoA, which fuels central biochemical reactions such as the synthesis of fatty acids, cholesterol and acetylcholine, and the acetylation of proteins and histones. We had previously reported that, although loss of Drosophila ATPCL reduced levels of Acetyl-CoA, unlike its human counterpart, it does not affect global histone acetylation and gene expression, suggesting that its role in histone acetylation is either partially redundant in Drosophila or compensated by alternative pathways. Here, we describe that depletion of DmATPCL affects spindle organization, cytokinesis, and fusome assembly during male meiosis, revealing an unanticipated role for DmATPCL during spermatogenesis. We also show that DmATPCL mutant meiotic phenotype is in part caused by a reduction of fatty acids, but not of triglycerides or cholesterol, indicating that DmATPCL-derived Acetyl-CoA is predominantly devoted to the biosynthesis of fatty acids during spermatogenesis. Collectively, our results unveil for the first time an involvement for DmATPCL in the regulation of meiotic cell division, which is likely conserved in human cells

A causal approach to test empirical capital structure regularities

Capital structure theories are often formulated as causal narratives to explain which factors drive financing choices. These narratives are usually examined by estimating cross–sectional relations between leverage and its determinants. However, the limitations of causal inference from observational data are often overlooked. To address this issue, we use structural causal modeling to identify how classic determinants of leverage are causally linked to capital structure and how this causal structure influences the effect-estimation process. The results provide support for the causal role of variables that measure the potential for information asymmetry concerning firms’ market values. Overall, our work provide a crucial step to connect capital structure theories with their empirical tests beyond simple correlations