Karyotype of a Bagrid catfish, Mystus vittatus, from the freshwater system of Chidambaram, Tamil Nadu, India

Karyological characters of Mystus vittatus (Bagridae) in the freshwater system of Chidambaram were studied by examining metaphase chromosome spreads from the gill tissues. The examination of 149 metaphase spreads prepared from 25 fingerling specimens indicated that the chromosome number of this species was 2n=54 and the arm number was 12 for metacentric, 36 for submetacentric, and 30 for acrocentric type. The prepared karyotypes of this species consisted, of 3 pairs of metacentric (m), 9 pairs of submetacentric (sm) and 15 pairs of acrocentric (a) chromosomes. The chromosome formula can be represented as 2n = 3m + 9sm + 15a. This karyotype is significantly different from same species reported by others. Karyological parameters showed that centrometric index, arm ratio, relative length, and length variation range of chromosome of this fish species are between 14.97-50.00, 1.00-5.68, 3.12-18.48, and 0.60-3.56, respectively. The largest chromosome in this species is a pair of submetacentric chromosomes. Considering the number of chromosomes, it seems likely that M. vittatus, is a diploid origin fish

Corporate governance and information technology : findings from an exploratory survey of Australian organizations

An exploratory survey (n = 57) of the Melbourne Chapter of the Information Systems Audit and Control Association was conducted to ascertain the attitudes and practices relating to corporate governance and the corporate governance of Information Technology (CGIT) in Australia. The survey found the respondents had clear views on corporate governance but most were not engaged with it, the organizational approach to corporate governance and its expected benefits was largely conformance oriented, awareness of CGIT management frameworks and associated standards was high but implementation was not widespread, and although the CGIT standard ISOIIEC 38500 was not widely implemented IT practitioners agreed with its principles. We conclude that the value of the CGIT standard has yet to be recognised by executives in Australia.<br /

LCDG4 and DigiSim - Simulation activities at NICADD/NIU

We present two software packages developed to support detector R&D studies for the International Linear Collider. LCDG4 is a full-detector simulator that provides energy deposits from particles traversing the sensitive volumes of the detector. It has been extensively used within the American ILC community, providing data for algorithm development and detector optimization studies. DigiSim models real-life digitization effects, converting the idealized response into simulated detector readout. It has many useful features to improve the realism in modeling detector response. The main characteristics of these two complementary packages are discussed.Comment: 8 pages, 7 figures, submitted to LCWS05 conference proceedings. Uses slac_one.rt

Systems Theoretic Process Analysis of a Run Time Assured Neural Network Control System

This research considers the problem of identifying safety constraints and developing Run Time Assurance (RTA) for Deep Reinforcement Learning (RL) Tactical Autopilots that use neural network control systems (NNCS). This research studies a specific use case of an NNCS performing autonomous formation flight while an RTA system provides collision avoidance and geofence assurances. First, Systems Theoretic Accident Models and Processes (STAMP) is applied to identify accidents, hazards, and safety constraints as well as define a functional control system block diagram of the ground station, manned flight lead, and surrogate unmanned wingman. Then, Systems Theoretic Process Analysis (STPA) is applied to the interactions of the the ground station, manned flight lead, surrogate unmanned wingman, and internal elements of the wingman aircraft to identify unsafe control actions, scenarios leading to each, and safety requirements to mitigate risks. This research is the first application of STAMP and STPA to an NNCS bounded by RTA

Improvement of Hamstring Flexibility: A Comparison between Two PNF Stretching Techniques

Objective: To determine the effectiveness of two PNF stretching techniques for improving hamstring flexibility and to compare the effectiveness of two PNF stretching techniques (Hold Relax and Contract Relax-Antagonist Contract) for improving hamstring flexibility. Subjects: 45 normal healthy male subjects. Design: A randomised pre-test post-test control group design. Method: The subjects were randomly assigned into three groups each consisting of 15 subjects. Hamstring flexibility for each group was measured using the active knee extension (AKE) test. Subjects of group A were treated with PNF hold relax stretching, whereas the subjects of group B were treated with PNF CRAC technique. The subjects of group C served as control group and were not subjected to any type of stretching. For each experimental group, stretch was performed three times a week for a total training period of three weeks. Results: A repeated-measures analysis of variance (ANOVA) and a Post HOC analysis using Bonferroni comparisons was used to determine and compare the effectiveness of two PNF stretching techniques at the end of 3 weeks of training protocol. The results demonstrated significant improvement in hamstring flexibility for subjects of group B when compared with those of group A (P = 0.03) at the end of three weeks, with improvement ranging from 0.50 to 15.66 degrees of active knee extension ROM at 95 % confidence interval. Conclusion: Both the techniques viz. PNF Hold Relax and PNF-CRAC are almost equal in their clinical effectiveness for improving hamstring flexibility and that either of the techniques may be used in clinical practice for improving hamstring flexibility