Anomaly Detection and Anticipation in High Performance Computing Systems

In their quest toward Exascale, High Performance Computing (HPC) systems are rapidly becoming larger and more complex, together with the issues concerning their maintenance. Luckily, many current HPC systems are endowed with data monitoring infrastructures that characterize the system state, and whose data can be used to train Deep Learning (DL) anomaly detection models, a very popular research area. However, the lack of labels describing the state of the system is a wide-spread issue, as annotating data is a costly task, generally falling on human system administrators and thus does not scale toward exascale. In this article we investigate the possibility to extract labels from a service monitoring tool (Nagios) currently used by HPC system administrators to flag the nodes which undergo maintenance operations. This allows to automatically annotate data collected by a fine-grained monitoring infrastructure; this labelled data is then used to train and validate a DL model for anomaly detection. We conduct the experimental evaluation on a tier-0 production supercomputer hosted at CINECA, Bologna, Italy. The results reveal that the DL model can accurately detect the real failures, and, moreover, it can predict the insurgency of anomalies, by systematically anticipating the actual labels (i.e., the moment when system administrators realize when an anomalous event happened); the average advance time computed on historical traces is around 45 minutes. The proposed technology can be easily scaled toward exascale systems to easy their maintenance

An Explainable Model for Fault Detection in HPC Systems

Large supercomputers are composed of numerous components that risk to break down or behave in unwanted manners. Identifying broken components is a daunting task for system administrators. Hence an automated tool would be a boon for the systems resiliency. The wealth of data available in a supercomputer can be used for this task. In this work we propose an approach to take advantage of holistic data centre monitoring, system administrator node status labeling and an explainable model for fault detection in supercomputing nodes. The proposed model aims at classifying the different states of the computing nodes thanks to the labeled data describing the supercomputer behaviour, data which is typically collected by system administrators but not integrated in holistic monitoring infrastructure for data center automation. In comparison the other method, the one proposed here is robust and provide explainable predictions. The model has been trained and validated on data gathered from a tier-0 supercomputer in production

A Framework for Estimating Future Traffic Operation and Safety Performance of Restricted Crossing U-Turn (RCUT) Intersections

Background: Despite numerous studies demonstrating the effectiveness of Restricted Crossing U-Turn (RCUT) intersection design, its implementation remains uneven and close to zero in some large states, including California. This paper provides a comprehensive framework to estimate the operational and safety performance of future RCUT designs. The framework is demonstrated for a geometrically constrained intersection located on a highspeed rural expressway. The operational evaluation relies on microscopic simulation models of existing TWSC and alternate RCUT designs used to estimate network-wide performance measures. Methods: Two approaches are demonstrated for future safety estimation; first, an HSM-prescribed Empirical Bayes (EB) approach that uses Safety Performance Function (SPF) predictions combined with the crash history of the site. For typical applications, EB estimates may be combined with CMFs for RCUT found in the literature. This approach remains the preferred option for safety estimation. However, for geometrically constrained locations where atypical RCUT designs need to be evaluated, a surrogate measure-based approach that uses trajectory data from the simulation model is described. Results: Surrogate measure-based safety analysis revelated that the RCUT design with no-left turn from mainline would be the most appropriate design for this location. Conclusion: The framework demonstrated here may be used by agencies to estimate the future benefits of the first-time application of treatments that have been successful elsewhere

Why honey is effective as a medicine. 1. Its use in modern medicine

Honey has been used as a medicine for thousands of years and its curative properties are well documented. However, modern medicine turned its back on honey and it is only now, with the advent of multi-resistant bacteria, that the antibiotic properties of honey are being rediscovered

Prevalence of toxoplasmic retinochoroiditis in an Australian adult population: A community-based study

Purpose: Toxoplasmic retinochoroiditis is the most common clinical manifestation of an infection with the protozoan parasite, Toxoplasma gondii. Up to 50 % of the human population is estimated to be infected with T. gondii; however, the epidemiology of toxoplasmic retinochoroiditis has not been widely reported. We sought to estimate the prevalence of toxoplasmic retinochoroiditis in Australia using data that were collected as part of the Busselton Healthy Ageing Study. Design: oss-sectional, community-based, prospective cohort study. Participants: 5020 Australian adults (2264 men and 2756 women; age range, 45–69 years, and median age, 58 years). Methods : Retinal color photographs, centered on the optic disc and macula, were captured using a digital retinal camera after the dilation of the pupils. Three uveitis-subspecialized ophthalmologists assessed each pigmented retinal lesion, and complete concordance of opinion was required to assign a toxoplasmic etiology. Serum T. gondii immunoglobulin (Ig)G levels were measured for those participants with retinal lesions judged to be toxoplasmic retinochoroiditis. Main Outcome Measures : Prevalence of toxoplasmic retinochoroiditis. Results: Eight participants (0.16 %) had retinal lesions that were considered to have the characteristic appearance of toxoplasmic retinochoroiditis, plus detectable serum T. gondii IgG, consistent with the diagnosis of toxoplasmic retinochoroiditis. On the assumption that 23.81 % of retinal lesions occur at the posterior pole, as reported in a community-based survey conducted in Brazil (Sci Rep. 2021;11:3420), the prevalence of toxoplasmic retinochoroiditis was estimated to be 0.67 % or 1 per 149 persons. Conclusions: Toxoplasmic retinochoroiditis is common in Australian adults. Efforts to quantify and address risk factors for human infection with T. gondii are justified

Tiller Population Density and Sward Stability of Brachiaria brizantha Continuously Stocked by Cattle

Tiller population density is one the most important parameters of sward structure and its evaluation is normally included in studies of sward dynamics. Moreover, a greater level of understanding is achieved when the survival of successive tiller generations is monitored. (Matthew et al., 2000). This would help to explain seasonal variation in tiller populations based on tiller appearance and death rates. While Brachiaria brizantha c.v. Marandu occupies up to 70 million hectares of cultivated grassland in Brazil, little is known of its ecophysiology. The objective of this work was to calculate survival probability of B. brizantha tillers and identify seasonal variation on sward stability

Herbage Intake and Animal Performance of Cattle Grazing \u3cem\u3eBrachiaria brizantha\u3c/em\u3e cv. Marandu Under Continuous Stocking

Grazing management affects sward structure, which in turn influences plant and animal responses. With the objective of understanding causal relationship between sward structure and animal responses, the present experiment evaluated the daily herbage intake and live weight gain of growing cattle on Brachiaria brizantha cv. Marandu pasture during summer (Dec. 2001 to Mar. 2002)

The Antibacterial Activity of Honey Derived from Australian Flora

Chronic wound infections and antibiotic resistance are driving interest in antimicrobial treatments that have generally been considered complementary, including antimicrobially active honey. Australia has unique native flora and produces honey with a wide range of different physicochemical properties. In this study we surveyed 477 honey samples, derived from native and exotic plants from various regions of Australia, for their antibacterial activity using an established screening protocol. A level of activity considered potentially therapeutically useful was found in 274 (57%) of the honey samples, with exceptional activity seen in samples derived from marri (Corymbia calophylla), jarrah (Eucalyptus marginata) and jellybush (Leptospermum polygalifolium). In most cases the antibacterial activity was attributable to hydrogen peroxide produced by the bee-derived enzyme glucose oxidase. Non-hydrogen peroxide activity was detected in 80 (16.8%) samples, and was most consistently seen in honey produced from Leptospermum spp. Testing over time found the hydrogen peroxide-dependent activity in honey decreased, in some cases by 100%, and this activity was more stable at 4°C than at 25°C. In contrast, the non-hydrogen peroxide activity of Leptospermum honey samples increased, and this was greatest in samples stored at 25°C. The stability of non-peroxide activity from other honeys was more variable, suggesting this activity may have a different cause. We conclude that many Australian honeys have clinical potential, and that further studies into the composition and stability of their active constituents are warranted

Antimicrobial activity of two South African honeys produced from indigenous Leucospermum cordifolium and Erica species on selected micro-organisms

<p>Abstract</p> <p>Background</p> <p>Honey has been shown to have wound healing properties which can be ascribed to its antimicrobial activity. The antimicrobial activity can be effective against a broad spectrum of bacterial species especially those of medical importance. It has also been shown that there is considerable variation in the antimicrobial potency of different types of honey, which is impossible to predict. With this in mind we tested the antimicrobial activity of honeys produced from plants grown in South Africa for their antibacterial properties on selected standard strains of oral micro-organisms.</p> <p>Methods</p> <p>The honeys used were produced from the blossoms of <it>Eucalyptus cladocalyx </it>(Bluegum) trees, an indigenous South African plant <it>Leucospermum cordifolium </it>(Pincushion), a mixture of wild heather shrubs, mainly <it>Erica </it>species (Fynbos) and a <it>Leptospermum scoparium </it>(Manuka) honey. Only pure honey which had not been heated was used. The honeys were tested for their antimicrobial properties with a broth dilution method.</p> <p>Results</p> <p>Although the honeys produced some inhibitory effect on the growth of the micro-organisms, no exceptionally high activity occurred in the South African honeys. The carbohydrate concentration plays a key role in the antimicrobial activity of the honeys above 25%. However, these honeys do contain other antimicrobial properties that are effective against certain bacterial species at concentrations well below the hypertonic sugar concentration. The yeast <it>C. albicans </it>was more resistant to the honeys than the bacteria. The species <it>S. anginosus </it>and <it>S. oralis </it>were more sensitive to the honeys than the other test bacteria.</p> <p>Conclusion</p> <p>The honeys produced from indigenous wild flowers from South Africa had no exceptionally high activity that could afford medical grade status.</p

The antibacterial properties of Malaysian tualang honey against wound and enteric microorganisms in comparison to manuka honey

<p>Abstract</p> <p>Background</p> <p>Antibiotic resistance of bacteria is on the rise, thus the discovery of alternative therapeutic agents is urgently needed. Honey possesses therapeutic potential, including wound healing properties and antimicrobial activity. Although the antimicrobial activity of honey has been effectively established against an extensive spectrum of microorganisms, it differs depending on the type of honey. To date, no extensive studies of the antibacterial properties of tualang (<it>Koompassia excelsa</it>) honey on wound and enteric microorganisms have been conducted. The objectives of this study were to conduct such studies and to compare the antibacterial activity of tualang honey with that of manuka honey.</p> <p>Methods</p> <p>Using a broth dilution method, the antibacterial activity of tualang honey against 13 wound and enteric microorganisms was determined; manuka honey was used as the control. Different concentrations of honey [6.25-25% (w/v)] were tested against each type of microorganism. Briefly, two-fold dilutions of honey solutions were tested to determine the minimum inhibitory concentration (MIC) against each type of microorganism, followed by more assays within a narrower dilution range to obtain more precise MIC values. MICs were determined by both visual inspection and spectrophotometric assay at 620 nm. Minimum bactericidal concentration (MBC) also was determined by culturing on blood agar plates.</p> <p>Results</p> <p>By visual inspection, the MICs of tualang honey ranged from 8.75% to 25% compared to manuka honey (8.75-20%). Spectrophotometric readings of at least 95% inhibition yielded MIC values ranging between 10% and 25% for both types of honey. The lowest MBC for tualang honey was 20%, whereas that for manuka honey was 11.25% for the microorganisms tested. The lowest MIC value (8.75%) for both types of honey was against <it>Stenotrophomonas maltophilia</it>. Tualang honey had a lower MIC (11.25%) against <it>Acinetobacter baumannii </it>compared to manuka honey (12.5%).</p> <p>Conclusion</p> <p>Tualang honey exhibited variable activities against different microorganisms, but they were within the same range as those for manuka honey. This result suggests that tualang honey could potentially be used as an alternative therapeutic agent against certain microorganisms, particularly <it>A. baumannii </it>and <it>S. maltophilia</it>.</p