Magnetic Field Geometry in "Red" and "Blue" BL Lacs

We compare the systematics of the magnetic field geometry in the "red" low-energy peaked BL Lacs (LBLs) and "blue" high-energy peaked BL Lacs (HBLs) using VLBI polarimetric images. The LBLs are primarily "radio--selected" BL Lacs and the HBLs are primarily "X-ray selected". In contrast to the LBLs, which show predominantly transverse jet magnetic fields, the HBLs show predominantly longitudinal fields. Thus, while the SED peaks of core-dominated quasars, LBLs and HBLs form a sequence of increasing frequency, the magnetic field geometry does not follow an analogous sequence. We briefly investigate possible connections between the observed parsec-scale magnetic field structures and circular polarization measurements in the literature on various spatial scales.Comment: 12 pages, 5 figures, Proceedings of the Amsterdam workshop on "Circular polarisation from relativistic jet sources", to be published in Astrophysics and Space Science, eds. Rob Fender & J-P Macquar

Modelling Governance Indicators and Managing e-Business Information Systems

Information Systems are in growing demand in various business and government organizations. Despite increased competition, business growth and technology innovation, at times, we overlook the governance, transparency, integrity and business ethics, with the result, the quality of deliverable products and services is compromised. Several external factors such as corruption, ineffective governance, political instability, flawed regulations and violation of rules of law, unaccountability affect the connectivity between outside influences and technology implementations. To summarize, weak governance practices and unjustified business ethics are impediments to business IS implementations. Appropriate technological innovations and remedial measures are needed that can substantiate our adaptation and implementation measures. The challenges are examined in the form of a three-tiered technology development motivation, which consists of mitigation, adaptation and implementation actions. We explore the relevant issues and challenges, and the need for a holistic IS research approach with follow-up technological remedies and accountability of results in the affected geographies and demography. The purpose of the research is to build IS artefacts to link governance attributes with the lapses existing between information management, organization strategies and e-business needs. An integrated IS architecture is proposed to explore the congruence between governance indicators and e-business IS requirements. The study further explores the wide-ranging of governance indicators that affected the business IS development and implementation. Cognizance of governance facts and their modelling in e-business contexts are pathways to instigate business IS artefacts and manage their needs in industry scenarios. Based on empirical research done on attribute modelling for 200 governments worldwide, we articulate our research findings with a claim that the e-business objectives are accomplishable through successful implementation of IS architectures in industrial environments through improved governance and transparency. Various IS strategies emerge to rescue the business and organization openness and transparency. Mitigation and critical interrogation of governance indicators facilitate us understand the research phenomena and adaptation of IS artefacts that accustomed to e-business change management. Models describing affected governments, documentation in the form of multidimensional repositories, with sustainability-manifested management and accounting are the outcomes of the research. Implementation of articulated IS architecture, and its adaptations by business and government organizations ensure us smart and sustainable e-business solutions in place, operationalizing governance policies, as adhered by various stakeholders. The research offers sustainable IS artefacts and online services to multiple government organizations and businesses. The benefits of the research are multifold, and they are improved internal operations and delivery of quality public services through established electronic services. Reduced waiting times, raising transparency, reinforcing equalities, and smoothening of the overall functioning of the organizations are added benefits of the study. Cost savings, improved communications, and increased government accountability are other gains of the study

Low-frequency radio observations of Seyfert galaxies: A test to the unification scheme

Aims. We present low-frequency radio imaging and spectral properties of a well defined sample of Seyfert galaxies using GMRT 240/610 MHz dual frequency observations. Radio spectra of Seyfert galaxies over 240 MHz to 5.0 GHz are investigated using 240 MHz, 610 MHz flux densities derived from GMRT, and 1.4 GHz and 5.0 GHz flux densities mainly from published VLA data. We test the predictions of Seyfert unification scheme by comparing the radio properties of Seyfert type 1s and type 2s. Methods. We choose a sample such that the two Seyfert subtypes have matched distributions in parameters that are independent to the orientation of AGN, obscuring torus and the host galaxy. Our sample selection criteria allow us to assume that the two Seyfert subtypes are intrinsically similar within the framework of the unification scheme. Results. The new observations at 240/610 MHz, together with archival observations at 1.4 GHz, 5.0 GHz show that type 1s and type 2s have statistically similar radio luminosity distributions at 240 MHz, 610 MHz, 1.4 GHz and 5.0 GHz. The spectral indices at selected frequency intervals as well as index measured over 240 MHz to 5.0 GHz for the two Seyfert subtypes have similar distributions with median spectral index $/sim$ -0.7, consistent with the synchrotron emission from optically thin plasma. In our snap-shot 240/610 MHz GMRT observations, most of the Seyfert galaxies show primarily an unresolved central radio component, except a few sources in which faint kpc-scale extended emission is apparent at 610 MHz. Our results on the statistical comparison of the multifrequency radio properties of our sample Seyfert galaxies are in agreement with the predictions of the Seyfert unification scheme.Comment: 21 pages, 5 figures, Accepted for publication in Astronomy & Astrophysic

Information System Guided Supply Chains and their Visual Analytics in Integrated Project Management

From a digital ecosystem perspective, sustainability is a manifestation of a composite entity with multiple data attribute dimensions. The data relationships may emerge between geographically distributed supply chain management ecosystems and their linked human, economic and environment ecologies. The ecosystems may exhibit inherent connections and interactions. For making connections more resilient, we characterize models that serve multiple industries through numerous data associations, even in Big Data scales. In the context of Integrated Project Management (IPM), the knowledge of boundaries between systems is mysterious, analysing diverse ecosystems through a sustainable framework can uncover new insights of inherent connections. The purpose of this research is to develop a holistic information system approach, in which multidimensional data and their connectivity are analysed, recognizing the ontological cogency, uniqueness of ecosystems and their data sources. The research outcome has facilitated the tactical development of strategies for ameliorating the sustainability challenges in the IPM contexts

Characterisation of Schiff base and chromophore in green proteorhodopsin by solid-state NMR

The proteorhodopsin family consists of hundreds of homologous retinal containing membrane proteins found in bacteria in the photic zone of the oceans. They are colour tuned to their environment and act as light-driven proton pumps with a potential energetic and regulatory function. Precise structural details are still unknown. Here, the green proteorhodopsin variant has been selected for a chemical shift analysis of retinal and Schiff base by solid-state NMR. Our data show that the chromophore exists in mainly all-trans configuration in the proteorhodopsin ground state. The optical absorption maximum together with retinal and Schiff base chemical shifts indicate a strong interaction network between chromophore and opsin. © Springer Science+Business Media B.V. 2007

The Nuclear Reddening Curve for Active Galactic Nuclei and the Shape of the Infra-Red to X-Ray Spectral Energy Distribution

We present extinction curves derived from the broad emission lines and continua of large samples of both radio-loud and radio-quiet AGNs. The curves are significantly flatter in the UV than are curves for the local ISM. The reddening curves for the radio-quiet LBQS quasars are slightly steeper than those of the radio-loud quasars in the UV, probably because of additional reddening by dust further out in the host galaxies of the former. The UV extinction curves for the radio-loud AGNs are very flat. This is explicable with slight modifications to standard MRN dust models: there is a relative lack of small grains in the nuclear dust. Our continuum and broad-emission line reddening curves agree in both shape and amplitude, confirming that the continuum shape is indeed profoundly affected by reddening for all but the bluest AGNs. With correction by our generic extinction curve, all of the radio-loud AGNs have continuous optical-UV spectra consistent with a single shape. We show that radio-quiet AGNs have very similar intrinsic UV to optical shape over orders of magnitude in luminosity. We also argue that radio-loud and radio-quiet AGNs probably share the same underlying continuum shape and that most of the systematic differences between their observed continuum shapes are due to higher nuclear reddening in radio-selected AGNs, and additional reddening from dust further out in the host galaxies in radio-quiet AGNs. Our conclusions have important implications for the modelling of quasar continua and the analysis of quasar demographics.Comment: 41 pages, including 6 figures and 3 tables. To appear in ApJ vol. 614, October 20 issue. Some slight wording changes. Some additional references added. Small changes in the model fit in section 6.2, to the analytical fit in the Appendix, and to the tabulated reddening curve in the Appendi

Electrochemical heavy metal detection, photocatalytic, photoluminescence, biodiesel production and antibacterial activities of Ag�ZnO nanomaterial

Zinc oxide nanoparticles (ZnO Nps) and silver doped zinc oxide nanoparticles (Ag�ZnO Nps) were prepared using nitrates of zinc and silver as oxidizers and succinic acid as a fuel through solution combustion synthesis (SCS) at 400 °C. The synthesized materials were characterized by various analytical techniques such as XRD, FTIR, Raman UV�vis, PL, SEM, EDX and TEM. The synthesized nanomaterials were tested for the photocatalytic degradation of methylene blue and the result reveal that Ag�ZnO Nps shows the better photocatalytic activity compared to undoped ZnO Nps. Biodiesel production from Simarouba oil shows that Ag�ZnO Nps acts as good catalyst compare to ZnO Nps, we have also developed sensor which showed a linearity in the concentration range 50�350 nM and limit of detection was found to be 3.5 and 3.8 nM (3�) for lead and cadmium respectively. Further we have examined the antibacterial activity against Escherichia coli and Staphylococcus aureus bacteria. © 2017 Elsevier Lt