Nuclear bars and blue nuclei within barred spiral galaxies

Multicolour near IR photometry for a sample of 32 large barred spiral galaxies is presented. By applying ellipse fitting techniques, we identify significant isophote twists with respect to the primary bar axis in the nuclear regions of $\sim$70 \%\ of the sample. These twists are identified in galaxies as late as SBbc and are clearly distinguishable from spiral arm morphology. At most seven of the galaxies with isophote twists are inferred to possess secondary (nuclear) bars, the axis ratios of which appear to correlate with morphological type. The remainder may result from triaxial bulges, or from oblate bulges misaligned with the primary bar. The near IR colour distributions in these data show evidence for (red) circumnuclear star forming rings in 4 galaxies. The majority of the sample (19) also possess striking blue nuclear regions, bluer than typical old stellar populations by $\sim$0.3 mag. in (J--H) and $\sim$0.23 mag. in (H--K). Such blue colours do not appear to correlate with the presence of nuclear rings or pseudo--rings, nor with the activity of the host galaxy (as determined from emission--line spectroscopic characteristics). Several mechanisms to explain this blue colour are considered.Comment: 24 pages plain LaTex( including table captions), 5 tables and 18 figures. Accepted for publication in MNRAS. Paper and tables available via anonymous ftp://143.167.4.101/pub/papers as sqiid-paper.tex and table1,2,3.tex, table4.ps, table5.ps. Figures available as postcript upon request to first Autho

A probabilistic analysis framework for malicious insider threats

Malicious insider threats are difficult to detect and to mitigate. Many approaches for explaining behaviour exist, but there is little work to relate them to formal approaches to insider threat detection. In this work we present a general formal framework to perform analysis for malicious insider threats, based on probabilistic modelling, verification, and synthesis techniques. The framework first identifies insiders' intention to perform an inside attack, using Bayesian networks, and in a second phase computes the probability of success for an inside attack by this actor, using probabilistic model checking

Design of an Energy Management System for Secure Integration of Renewable Energy Sources into Microgrids

This chapter presents the design and development of an energy management system (EMS), which guarantees a secure operation of an islanded microgrid under possible imbalances between generation capacity and loads demand. The EMS performs an optimal calculation of low priority loads to be shed, as well as charging and discharging cycles of batteries within the microgrid. A nonlinear model‐predictive control (NMPC) algorithm is selected for implementing the EMS, which processes a data set composed of loads measurements, generation capacity, batteries state of charge (SOC), and a set of operation constraints. The EMS is designed under the assumption of having an advanced metering infrastructure (AMI) installed in the microgrid. The EMS is tested in a simulation platform that integrates models of the microgrid components, as well as their distributed controllers (DCs). Simulation results show the effectiveness of the proposed approach, since critical variables as the microgrid’s frequency and voltage magnitude operate within a secured interval even under the presence of faults in one of the DCs

Model based analysis of insider threats

In order to detect malicious insider attacks it is important to model and analyse infrastructures and policies of organisations and the insiders acting within them. We extend formal approaches that allow modelling such scenarios by quantitative aspects to enable a precise analysis of security designs. Our framework enables evaluating the risks of an insider attack to happen quantitatively. The framework first identifies an insider's intention to perform an inside attack, using Bayesian networks, and in a second phase computes the probability of success for an inside attack by this actor, using probabilistic model checking. We provide prototype tool support using Matlab for Bayesian networks and PRISM for the analysis of Markov decision processes, and validate the framework with case studies

Sainfoin – New Data on Anthelmintic Effects and Production in Sheep and Goats

Gastrointestinal nematodes (GIN) are one of the most important problems affecting health and therefore performance and welfare in small ruminant husbandry. The control of these parasites in the past strongly relied on the repeated use of anthelmintic drugs. This has led to nematode populations which are resistant to most of the currently available anthelmintics. Furthermore customer’s demands for organic and residue free animal products are increasing. The aforementioned problems have given a strong impetus for the development of new non-chemical strategies to control GIN. Previous research has pointed out the anthelmintic potential of sainfoin (Onobrychis viciifolia) and other tanniferous (CT) feed sources in goats and lambs infected with GIN. A recent Swiss experiment focussed on the use of sainfoin and field bean (Vicia faba, cv. Scirocco) as single CT sources as well as in combination for additional synergic effects, to reduce periparturient GIN egg rise of ewes in late gestation and early lactation. Another experiment with Alpine goats concentrated on the influence of sainfoin on milk performance and cheese quality. The results of these experiments will be presented and discussed in connection with previous knowledge on (i) anthelmintic effects of sainfoin and (ii) the influence of sainfoin administration on performance

Superconductivity at 17 K in Yttrium Metal under Nearly Hydrostatic Pressures to 89 GPa

In an experiment in a diamond anvil cell utilizing helium pressure medium, yttrium metal displays a superconducting transition temperature which increases monotonically from Tc ? 3.5 K at 30 GPa to 17 K at 89.3 GPa, one of the highest transition temperatures for any elemental superconductor. The pressure dependence of Tc differs substantially from that observed in previous studies under quasihydrostatic pressure to 30 GPa. Remarkably, the dependence of Tc on relative volume V/Vo is linear over the entire pressure range above 33 GPa, implying that higher values of Tc are likely at higher pressures. For the trivalent metals Sc, Y, La, Lu there appears to be some correlation between Tc and the ratio of the Wigner-Seitz radius to the ion core radius.Comment: submitted for publicatio

Searching for the Annual Modulation of Dark Matter signal with the GENIUS-TF experiment

The annual modulation of the recoil spectrum observed in an underground detector is well known as the main signature of a possible WIMP signal. The GENIUS-TF experiment, under construction in the Gran Sasso National Laboratory, can search for the annual modulation of the Dark Matter signal using 40 kg of naked-Ge detectors in liquid nitrogen. Starting from a set of data simulated under the hypothesis of modulation and using different methods, we show the potential of GENIUS-TF for extracting the modulated signal and the expected WIMP mass and WIMP cross section.Comment: In press, Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment (2003) and in Proc. of IDM2002, York Minster, England, 2-6 September, 2002, World Scientific 200

Implementation of maternity protection legislation: Gynecologists' perceptions and practices in French-speaking Switzerland.

In several countries, maternity protection legislations (MPL) confer an essential role to gynecologist-obstetricians (OBGYNs) for the protection of pregnant workers and their future children from occupational exposures. This study explores OBGYNs' practices and difficulties in implementing MPL in the French-speaking part of Switzerland. An online survey was sent to 333 OBGYNs. Data analysis included: 1) descriptive and correlational statistics and 2) hierarchical cluster analysis to identify patterns of practices. OBGYNs evoked several problems in MPL implementation: absence of risk analysis in the companies, difficult collaboration with employers, lack of competencies in the field of occupational health. Preventive leave was underused, with sick leave being prescribed instead. Training had a positive effect on OBGYNs' knowledge and implementation of MPL. Hierarchical cluster analysis highlighted three main types of practices: 1) practice in line with legislation; 2) practice on a case-by-case basis; 3) limited practice. OBGYNs with good knowledge of MPL more consistently applied its provisions. The implementation of MPL appears challenging for OBGYNs. Collaboration with occupational physicians and training might help OBGYNs to better take on their role in maternity protection. MPL in itself could be improved

Midwives and protection of pregnant workers in Western Switzerland: Practices, difficulties and contributions.

Switzerland's maternity protection legislation aims to protect the health of pregnant employees and their unborn children by regulating their potential occupational exposure to hazards and strenuous activities. This legislation provides a role for obstetricians, but not for midwives. Identify the practices of Switzerland's French-speaking midwives that favour the implementation of maternity protection legislation and reflect on the profession's role in supporting pregnant employees. 356 midwives answered an online questionnaire. The analysis focuses on the 205 midwives who perform pregnancy consultations in their practice. Data were analysed in two stages using STATA software: 1) simple descriptive and correlational statistics and 2) hierarchical cluster analysis to identify typologies of practices by grouping similar responses. Despite having no officially defined role in Switzerland's maternity protection legislation, its midwives actively participate in protecting pregnant employees , especially those with more knowledge of the legislation, those with more years of experience and those practicing independently. The barriers that midwives face when trying to provide greater support for pregnant employees are linked significantly to their lack of knowledge about the legislation, a lack of recognition for their role in the current legislation and a lack of continuing education about the occupational health risks associated with pregnancy at work. Their profession and specific practices give midwives privileged access to pregnant employees. Midwives' knowledge of the legislation, their awareness of the occupational risks and hazards facing pregnant employees and the conviction that their profession has the potential to make a difference could all be improved. The role of midwives should be-and deserves to be-formally and legally recognised and integrated into Switzerland's maternity protection legislation