A Case of Hyperkalemia Versus Pseudohyperkalemia in Chronic Lymphocytic Leukemia

Introduction: Both hyperkalemia and pseudohyperkalemia occur in the emergency department. True hyperkalemia necessitates emergent treatment while pseudohyperkalemia requires recognition to prevent inappropriate treatment. It is imperative that the emergency physician (EP) have an understanding of the causes and clinical presentations of both phenomena.Case Report: We present a case of an 88-year-old male with chronic lymphocytic leukemia (CLL) and suspected blast crisis who was found to have elevated serum potassium levels without other manifestations of hyperkalemia and eventually was determined to have pseudohyperkalemia due to white cell fragility.Discussion: Differentiation of hyperkalemia and pseudohyperkalemia is a critical skill for the EP. We discuss multiple causes of hyperkalemia and pseudohyperkalemia in an effort to broaden the knowledge base.Conclusion: We present a case of CLL as an unusual cause of pseudohyperkalemia and review common causes of pseudohyperkalemia

Topological Insulators and Mott Physics from the Hubbard Interaction

We investigate the Hubbard model on the honeycomb lattice with intrinsic spin orbit interactions as a paradigm for two-dimensional topological band insulators in the presence of interactions. Applying a combination of Hartree-Fock theory, slave-rotor techniques, and topological arguments, we show that the topological band insulating phase persists up to quite strong interactions. Then we apply the slave-rotor mean-field theory and find a Mott transition at which the charge degrees of freedom become localized on the lattice sites. The spin degrees of freedom, however, are still described by the original Kane-Mele band structure. Gauge field effects in this region play an important role. When the honeycomb layer is isolated then the spin sector becomes already unstable toward an easy plane Neel order. In contrast, if the honeycomb lattice is surrounded by extra "screening" layers with gapless spinons, then the system will support a fractionalized topological insulator phase with gapless spinons at the edges. For large interactions, we derive an effective spin Hamiltonian.Comment: 20 pages, 12 figures; final published versio

IMPACT OF STRUCTURAL FUNDS ON REGIONAL GROWTH: HOW TO RECONSIDER A 9 YEAR-OLD BLACK BOX

Econometric estimations of the impact of structural funds on the growth process of the European regions started 9 years ago. However, it is striking to realize that all previous estimations in this field are based on some form of the neoclassical growth model. This model is still widely used despite the numerous critics it has raised and its lack of consideration for increasing returns to scale, which are at the heart of agglomeration and growth processes according to endogenous growth theories and new economic geography models. In addition, few estimations have paid attention to the nature of the cohesion objectives under study. For example, the expected impact of objec-tive 1 funds, devoted to public infrastructures, is indeed theoretically and empirically very different from the one of objective 3 funds devoted to long-term unemployed. As a result, the aim of this paper is to propose a careful assessment of the impact of structural funds on the manufacturing sector of 145 European regions in the context of a Verdoorn’s law for the period 1989-2004. First, the results are presented with total structural funds and funds differen-tiated by objective. Second, interregional linkages are included by means of spatial econometric techniques. Third, potential endogeneity of the explanatory variables is taken into account.GROWTH, REGIONAL POLICY, INCREASING RETURNS, EUROPE, SPATIAL ECONOMETRICS

Quantum Spin Hall Insulators with Interactions and Lattice Anisotropy

We investigate the interplay between spin-orbit coupling and electron-electron interactions on the honeycomb lattice combining the cellular dynamical mean-field theory and its real space extension with analytical approaches. We provide a thorough analysis of the phase diagram and temperature effects at weak spin-orbit coupling. We systematically discuss the stability of the quantum spin Hall phase toward interactions and lattice anisotropy resulting in the plaquette-honeycomb model. We also show the evolution of the helical edge states characteristic of quantum spin Hall insulators as a function of Hubbard interaction and anisotropy. At very weak spin-orbit coupling and intermediate electron-electron interactions, we substantiate the existence of a quantum spin liquid phase.Comment: 7 pages, 9 figures, final versio

The evolution of the spatial and sectoral patterns in Ile-de-France over 1978-1997

The aim of this paper is to analyze the intra-urban spatial distribution of employment in the agglomeration of Ile-de-France in 1978 and 1997. In that purpose, exploratory spatial data analysis is used in order to identify employment centers and a sectoral analysis of the CBD and the subcenters is performed. Our results highlight a suburbanization process of employment between 1978 and 1997 in Ile-de-France. A more polarized space emerges in 1997 compared to 1978 with several employment centers specialized in different activities. Moreover, even if the spatial influence of the CBD is diminishing during the study period, the CBD preserves its economic leadership by concentrating a large variety of high-order producer services. Keywords: exploratory spatial data analysis; employment centers; spatial autocorrelation; suburbanization JEL Classification: C12, R12, R14

CSR firm profiles and innovation: An empirical exploration with survey data

This paper explores the relationship between different Corporate Social Responsibility (CSR) strategies and innovation. Using a survey carried out on CSR behavior of Luxembourg firms, we found two types of firms as far as CSR practices are concerned. Cluster 1 firms adopted CSR practices to achieve economic goals without resorting to the formalization of these practices. In contrast, cluster 2 firms "learn CSR by doing" and by establishing CSR procedures and tools. Then  we match Community Innovation Survey (CIS) data and specific data collected on CSR clusters. We estimate Logit models to explain the different types of innovation (product, process, organizational). In comparison with the firms which don't adopt CSR, firms in Cluster 1 are more innovative in  terms of product and process once we control for firm characteristics and innovation drivers while firms in cluster 2 tend to reject innovation in process and adopt organizational innovation. These results, which show the link between the various CSR practices and innovation types, have important consequences in terms of managerial recommendations and public policy support for innovation.Corporate Social Responsibility; Innovation; Organizational; Practices; Product; Process

Detecting Quantum Critical Points using Bipartite Fluctuations

We show that the concept of bipartite fluctuations F provides a very efficient tool to detect quantum phase transitions in strongly correlated systems. Using state of the art numerical techniques complemented with analytical arguments, we investigate paradigmatic examples for both quantum spins and bosons. As compared to the von Neumann entanglement entropy, we observe that F allows to find quantum critical points with a much better accuracy in one dimension. We further demonstrate that F can be successfully applied to the detection of quantum criticality in higher dimensions with no prior knowledge of the universality class of the transition. Promising approaches to experimentally access fluctuations are discussed for quantum antiferromagnets and cold gases.Comment: 5 pages, 6 figures + suppl. material; final version, Phys. Rev. Lett. (in press

Influence of microalgal N and P composition on wastewater nutrient remediation

Microalgae have demonstrated the ability to remediate wastewater nutrients efficiently, with methods to further enhance performance through species selection and biomass concentration. This work evaluates a freshwater species remediation characteristics through analysis of internal biomass N:P (nitrogen:phosphorus) and presents a relationship between composition and nutrient uptake ability to assist in species selection. Findings are then translated to an optimal biomass concentration, achieved through immobilisation enabling biomass intensification by modifying bead concentration, for wastewaters of differing nutrient concentrations at hydraulic retention times (HRT) from 3 h to 10 d. A HRT <20 h was found suitable for the remediation of secondary effluent by immobilised Scenedesmus obliquus and Chlorella vulgaris at bead concentrations as low as 3.2 and 4.4 bead·mL−1. Increasing bead concentrations were required for shorter HRTs with 3 h possible at influent concentrations <5 mgP L−1

General Relation between Entanglement and Fluctuations in One Dimension

In one dimension very general results from conformal field theory and exact calculations for certain quantum spin systems have established universal scaling properties of the entanglement entropy between two parts of a critical system. Using both analytical and numerical methods, we show that if particle number or spin is conserved, fluctuations in a subsystem obey identical scaling as a function of subsystem size, suggesting that fluctuations are a useful quantity for determining the scaling of entanglement, especially in higher dimensions. We investigate the effects of boundaries and subleading corrections for critical spin and bosonic chains.Comment: 4 pages, 2 figures. Minor changes, references added