Why the traditional concept of local hardness does not work

Finding a proper local measure of chemical hardness has been a long-standing aim of density functional theory. The traditional approach to defining a local hardness index, by the derivative of the chemical potential with respect to the electron density subject to the constraint of a fixed external potential, has raised several questions, and its chemical applicability has proved to be limited. Here, we point out that the only actual possibility to obtain a local hardness measure in the traditional approach emerges if the external potential constraint is dropped; consequently, utilizing the ambiguity of a restricted chemical potential derivative is not an option to gain alternative definitions of local hardness. At the same time, however, the arising local hardness concept turns out to be fatally undermined by its inherent connection with the asymptotic value of the second derivative of the universal density functional. The only other local hardness concept one may deduce from the traditional definition is the one that gives a constant value, the global hardness itself, throughout an electron system in its ground state. Consequently, the traditional approach is in principle incapable of delivering a local hardness indicator. The parallel case of defining a local version of the chemical potential itself is also outlined, arriving at a similar conclusion. Namely, the only local chemical potential concept that can be gained from a definition dE[n]/dn(r)|v is the one that gives a constant, mu itself, for electron systems in their ground state.Comment: 29 pages, to appear in Theor. Chem. Ac

A data recipient centered de-identification method to retain statistical attributes

AbstractPrivacy has always been a great concern of patients and medical service providers. As a result of the recent advances in information technology and the government’s push for the use of Electronic Health Record (EHR) systems, a large amount of medical data is collected and stored electronically. This data needs to be made available for analysis but at the same time patient privacy has to be protected through de-identification. Although biomedical researchers often describe their research plans when they request anonymized data, most existing anonymization methods do not use this information when de-identifying the data. As a result, the anonymized data may not be useful for the planned research project. This paper proposes a data recipient centered approach to tailor the de-identification method based on input from the recipient of the data. We demonstrate our approach through an anonymization project for biomedical researchers with specific goals to improve the utility of the anonymized data for statistical models used for their research project. The selected algorithm improves a privacy protection method called Condensation by Aggarwal et al. Our methods were tested and validated on real cancer surveillance data provided by the Kentucky Cancer Registry

Supplementary data for the article: Meszaros, J. P.; Poljarević, J.; Gal, T. G.; May, N. V.; Spengler, G.; Enyedy, E. A. Comparative Solution and Structural Studies of Half-Sandwich Rhodium and Ruthenium Complexes Bearing Curcumin and Acetylacetone. Journal of Inorganic Biochemistry 2019, 195, 91–100. https://doi.org/10.1016/j.jinorgbio.2019.02.015

Supplementary material for: [https://doi.org/10.1016/j.jinorgbio.2019.02.015]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/2873

Comparative solution and structural studies of half-sandwich rhodium and ruthenium complexes bearing curcumin and acetylacetone

Half-sandwich organometallic complexes of curcumin are extensively investigated as anticancer compounds.Speciation studies were performed to explore the solution stability of curcumin complexes formed with [Rh(η5- C5Me5)(H2O)3]2+. Acetylacetone (Hacac), as the simplest β-diketone ligand bearing (O,O) donor set, was involved for comparison and its Ru(η6‑p‑cymene), Ru(η6‑toluene) complexes were also studied. 1H NMR, UV–visible and pH-potentiometric titrations revealed a clear trend of stability constants of the acac complexes: Ru(η6‑p‑cymene) > Ru(η6‑toluene) > Rh(η5-C5Me5). Despite this order, the highest extent of complex formation is seen for the Rh(η5-C5Me5) complexes at pH 7.4. Formation constant of [Rh(η5-C5Me5)(H2curcumin) (H2O)]+ reveals similar solution stability to that of the acac complex. Additionally, structures of two complexes were determined by X-ray crystallography. The in vitro cytotoxicity of curcumin was not improved by the complexation with these organometallic cations.Supplementary material: [http://cherry.chem.bg.ac.rs/handle/123456789/2875]This is the peer-reviewed version of the following article: Meszaros, J. P.; Poljarević, J.; Gal, T. G.; May, N. V.; Spengler, G.; Enyedy, E. A. Comparative Solution and Structural Studies of Half-Sandwich Rhodium and Ruthenium Complexes Bearing Curcumin and Acetylacetone. Journal of Inorganic Biochemistry 2019, 195, 91–100. [https://doi.org/10.1016/j.jinorgbio.2019.02.015