Mechanism of charge transfer/disproportionation in LnCu3Fe4O12 (Ln: Lanthanides)

The Fe-Cu intersite charge transfer and Fe charge disproportionation are interesting phenomena observed in some LnCu3Fe4O12 (Ln: Lanthanides) compounds containing light and heavy Ln atoms, respectively. We show that a change in the spin state is responsible for the intersite charge transfer in the light Ln compounds. At the high spin state, such systems prefer an unusual Cu-d^8 configuration, whereas at the low spin state they retreat to the normal Cu-d^9 configuration through a charge transfer from Fe to Cu-3d_{xy} orbital. We find that the strength of the crystal field splitting and the relative energy ordering between Cu-3d_{xy} and Fe-3d states are the key parameters, determining the intersite charge transfer (charge disproportionation) in light (heavy) Ln compounds. It is further proposed that the size of Ln affects the onsite interaction strength of Cu-3d states, leading to a strong modification of the Cu-L_3 edge spectrum, as observed by the X-ray absorption spectroscopy.Comment: 6 pages, 5 figures, 1 table. To appear in PR

Information Content in Data Sets for a Nucleated-Polymerization Model

We illustrate the use of tools (asymptotic theories of standard error quantification using appropriate statistical models, bootstrapping, model comparison techniques) in addition to sensitivity that may be employed to determine the information content in data sets. We do this in the context of recent models [23] for nucleated polymerization in proteins, about which very little is known regarding the underlying mechanisms; thus the methodology we develop here may be of great help to experimentalists

Inferring the three-dimensional distribution of dust in the Galaxy with a non-parametric method: Preparing for Gaia

We present a non-parametric model for inferring the three-dimensional (3D) distribution of dust density in the Milky Way. Our approach uses the extinction measured towards stars at different locations in the Galaxy at approximately known distances. Each extinction measurement is proportional to the integrated dust density along its line-of-sight. Making simple assumptions about the spatial correlation of the dust density, we can infer the most probable 3D distribution of dust across the entire observed region, including along sight lines which were not observed. This is possible because our model employs a Gaussian Process to connect all lines-of-sight. We demonstrate the capability of our model to capture detailed dust density variations using mock data as well as simulated data from the Gaia Universe Model Snapshot. We then apply our method to a sample of giant stars observed by APOGEE and Kepler to construct a 3D dust map over a small region of the Galaxy. Due to our smoothness constraint and its isotropy, we provide one of the first maps which does not show the "fingers of god" effect.Comment: Minor changes applied. Final version accepted for publication in A&A. 15 pages, 17 figure

Defining CSFs for information systems strategic planning in holding companies: a case study of an Iranian managerial holding company (system group)

Holding companies (HCs) differ in their nature and behavior from other types of companies. Their role is to support, control and budget their subsidiaries. In general, HCs do not compete directly with one another, as it is difficult to find two HCs with the same product and service portfolios. Competition occurs instead at the subsidiary level against companies, which may or may not be part of other HCs, in overlapping markets with similar products and services. This concept of competition, which differs from that of typical commercial companies, is central to the development of HC strategies for supporting and controlling their subsidiaries. Information Systems Strategic Planning (ISSP) attempts to align information systems strategy with business strategy by directing the investment in information systems so as to satisfy strategic goals. Traditionally, ISSP methodologies have addressed the definition of information systems for Strategic Business Units (SBU). This research demonstrates, using a case study of an Iranian Managerial Holding Company, how ISSP can be applied instead to Strategic Business Processes (SBP). It illustrates how to define Critical Success Factors (CSFs) and Information System Needs (ISN) on Strategic Processes instead of Strategic Units. Moreover, this study combines the Balanced Scorecard (BSC) with a statistical questionnaire survey to define strategic processes

Socioeconomic inequality in tobacco expenditure in Iran: a cross-sectional analysis at national and subnational levels.

BACKGROUND:Tobacco expenditure has adverse impacts on expenditure on basic needs and resource allocation of the households. Using data from a nationally representative survey, we measured socioeconomic inequality in tobacco expenditure as the share of household budget (TEHB) and explained its main determinants among Iranian households at the national and sub-national levels. METHODS:This cross-sectional study used data from the Iranian Household Income and Expenditure Survey (IHIES), 2018. We included a total of 7649 households with tobacco expenditure more than zero in the analysis. Province-level data on the Human Development Index (HDI) was obtained from the Institute for Management Research at Radbound University. The concentration curve (CC) and the concentration index (C) were used to measure socioeconomic inequality in TEHB at national and sub-national levels. The C was decomposed to identify the factors explaining the observed socioeconomic inequality in TEHB. RESULTS:At the national level, households with at least one smoker spent more than 5% of their budget for tobacco consumption in the last month. Households from the urban areas allocated less of their budgets on tobacco products compared to rural households (4.6% vs. 5.8%). Overall, TEHB was more concentrated among the poorer households (C = 0.1423, 95% CI: - 0.1552 to - 0.1301). In other words, the distribution of TEHB was pro-poor in Iran. Pro-poor inequality in TEHB was also found in urban (C = - 0.1707, 95% CI: - 0.1998 to - 0.1516) and rural (C = - 0.1314, 95% CI: - 0.1474 to - 0.1152) areas. We also found that pro-poor inequalities were higher in Iranian provinces with low HDI. The decomposition results indicate that wealth and education were the main factors contributing to the concentration of TEHB among the poorer households. CONCLUSION:This study found that TEHB was disproportionality concentrated among poorer households in Iran. The extent of inequality in TEHB was higher in urban areas and less developed provinces. Designing and implementing tobacco control interventions to decrease the smoking prevalence and increase smoking cessation could protect worse-off households against the financial burden of tobacco spending

Generation of circular polarization of the CMB

According to the standard cosmology, near the last scattering surface, the photons scattered via Compton scattering are just linearly polarized and then the primordial circular polarization of the CMB photons is zero. In this work we show that CMB polarization acquires a small degree of circular polarization when a background magnetic field is considered or the quantum electrodynamic sector of standard model is extended by Lorentz-noninvariant operators as well as noncommutativity. The existence of circular polarization for the CMB radiation may be verified during future observation programs and it represents a possible new channel for investigating new physics effects.Comment: 28 pages, v3, Phys. Rev. D 81, 084035 (2010

Brand Value Co-Creation in the Social Commerce Era: Empirical Evidence From Iran

Brand value co-creation occurs when customers provide informational input to brand owners, which can be used to develop, refine or extend brands. Brand co-creation is an attractive and inexpensive marketing strategy for firms entering new markets and developing new brand meanings. The upward trend in social media use has transformed e-commerce by adding social support and information sharing features, resulting in social commerce. This research tests a framework that examines the e-commerce opportunities for firms from a branding perspective. Using a survey of Iranian consumers, SEM- PLS was used to analyse the data. Results provide new insights for a strategic approach to social media use in relation to the firm’s value co-creation objective. The results confirm the research model and emphasise the importance of social commerce constructs, social support, and relationship quality in brand value co-creation. The theoretical and practical implications are provided

Halotolerant Ability and α-Amylase Activity of Some Saltwater Fungal Isolates

Four halotolerant fungal isolates originating from the saltwater Lake Urmia in Iran were selected during a screening program for salt resistance and α-amylase activity. The isolates were identified based on sequencing the ITS region and a part of the β-tubulin gene, as Penicillium chrysogenum (isolate U1; CBS 132820), Fusarium incarnatum (isolate U2; CBS 132821), and Penicillium polonicum (isolate U3; CBS 132822, and isolate U4; CBS 132823). The growth of these isolates was determined by measuring the colony diameter and mycelia dry weight in Sabouraud dextrose agar and yeast nitrogen base medium supplemented with NaCl, KCl, and LiCl. Isolate U4 showed a growth up in 15% NaCl and U1 was the only isolate that could grow in 20% KCl. None of the strains grew in a media containing LiCl. The salt supplemented medium did not increase the size of colony diameter in all isolates (p > 0.05). The ability of the selected isolates for amylase production was quantitatively tested and showed that P. polonicum isolate U4 was the most potent producer of amylase with a yield of 260.9 U/L after 60 h, whereas P. polonicum isolate U3 was the lowest one with a production level of 97.9 U/L after 48 h. P. polonicum isolate U4 could be a suitable candidate for production of amylase on an industrial scale after optimization. © 2013 by School of Pharmacy