Seer: a lightweight online failure prediction approach

Online failure prediction aims to predict the manifestation of failures at runtime before the failures actually occur. Existing online failure prediction approaches typically operate on data which is either directly reported by the system under test or directly observable from outside system executions. These approaches generally refrain themselves from collecting internal execution data that can further improve the prediction quality. One reason behind this general trend is due to the runtime overhead cost incurred by the measurement instruments that are required to collect the data. In this work we conjecture that large cost reductions in collecting internal execution data for online failure prediction can derive from reducing the cost of the measurement instruments, while still supporting acceptable levels of prediction quality. To evaluate this conjecture, we present a lightweight online failure prediction approach, called Seer. Seer uses fast hardware performance counters to perform most of the data collection work. The data is augmented with further data collected by a minimal amount of software instrumentation that is added to the systems software. We refer to the data collected in this manner as hybrid spectra. We applied the proposed approach to three widely used open source subject applications and evaluated it by comparing and contrasting three types of hybrid spectra and two types of traditional software spectra. At the lowest level of runtime overheads attained in the experiments, the hybrid spectra predicted the failures about half way through the executions with an F-measure of 0.77 and a runtime overhead of 1.98%, on average. Comparing hybrid spectra to software spectra, we observed that, for comparable runtime overhead levels, the hybrid spectra provided significantly better prediction accuracies and earlier warnings for failures than the software spectra. Alternatively, for comparable accuracy levels, the hybrid spectra incurred significantly less runtime overheads and provided earlier warnings

Factors affecting the outcome of surgically treated non-iatrogenic traumatic cervical esophageal perforation: 28 years experience at a single center

<p>Abstract</p> <p>Background</p> <p>We reviewed our experience with non-iatrogenic traumatic cervical esophageal perforations, paying particular attention to factors affecting the outcome of such cases.</p> <p>Methods</p> <p>In total, 30 patients treated surgically between 1980 and 2008 for non-iatrogenic traumatic cervical esophageal perforation in our clinic were reviewed.</p> <p>Results</p> <p>There were 25 male and 5 female patients with a median age of 27.5 years. The type of injury was external trauma in 21 (70%) patients and endoluminal injury in the remaining 9 (30%) patients. The mechanism of injury was gunshot in 16 patients, stabbing in 4, falling in 1 (extraluminal injury), and foreign body in 9 (endoluminal injuries). The overall mortality rate was 16.6% (5/30). The mortality rate for extraluminal injuries was 19%, and for endoluminal injuries was 11.1%. Mortality in patients treated within 24 h of sustaining injury was substantially less than in those for whom diagnosis and treatment were delayed (12.5 and 21.4%, respectively). The mortality rate was 33.3% (3/9) for patients with tracheal injuries and 9.5% (2/21) for those without tracheal injuries.</p> <p>Conclusions</p> <p>A treatment delay greater than 24 h, the presence of tracheal injury, or extraluminal perforation significantly affected the outcome of surgically treated non iatrogenic traumatic cervical esophageal perforation.</p

The Role of Sublobar Resections in the Treatment of Small Cell Lung

WOS: 000446224000008Lobectomy is the standard treatment in the early stages of non-small cell lung cancer. Today, however, it is questioned whether lobectomy should be performed in all early diagnosed patients. Sublobar resection remains a treatment option in elderly patients with low cardiopulmonary reserve who cannot tolerate sublobar resection lobectomy. In small tumors measuring 2 cm in diameter, sublobar resections can provide local recurrence rates and long survival rates equivalent to lobectomy when performed with the appropriate techniques in eligible patients. The addition of brachytherapy can further improve the results

An Approach for Classifying Program Failures

Abstract—In this work, we leverage hardware performance counters-collected data to automatically group program failures that stem from closely related causes into clusters, which can in turn help developers prioritize failures as well as diagnose their causes. Hardware counters have been used for performance analysis of software systems in the past. By contrast, in this paper they are used as abstraction mechanisms for program executions. The results of our feasibility studies conducted on two widely-used applications suggest that hardware counters-collected data can be used to reliably classify failures. Keywords-failure classification; debugging aids; hardware performance counters. I

Wi-Fi (2.45 GHz)- and Mobile Phone (900 and 1800 MHz)-Induced Risks on Oxidative Stress and Elements in Kidney and Testis of Rats During Pregnancy and the Development of Offspring

The present study was designed to determine the effects of both Wi-Fi (2.45 GHz)- and mobile phone (900 and 1800 MHz)-induced electromagnetic radiation (EMR) on oxidative stress and trace element levels in the kidney and testis of growing rats from pregnancy to 6 weeks of age. Thirty-two rats and their 96 newborn offspring were equally divided into four different groups, namely, control, 2.45 GHz, 900 MHz, and 1800 MHz groups. The 2.45 GHz, 900 MHz, and 1,800 MHz groups were exposed to EMR for 60 min/day during pregnancy and growth. During the fourth, fifth, and sixth weeks of the experiment, kidney and testis samples were taken from decapitated rats. Results from the fourth week showed that the level of lipid peroxidation in the kidney and testis and the copper, zinc, reduced glutathione (GSH), glutathione peroxidase (GSH-Px), and total antioxidant status (TAS) values in the kidney decreased in the EMR groups, while iron concentrations in the kidney as well as vitamin A and vitamin E concentrations in the testis increased in the EMR groups. Results for fifth-week samples showed that iron, vitamin A, and beta-carotene concentrations in the kidney increased in the EMR groups, while the GSH and TAS levels decreased. The sixth week results showed that iron concentrations in the kidney and the extent of lipid peroxidation in the kidney and testis increased in the EMR groups, while copper, TAS, and GSH concentrations decreased. There were no statistically significant differences in kidney chromium, magnesium, and manganese concentrations among the four groups. In conclusion, Wi-Fi- and mobile phone-induced EMR caused oxidative damage by increasing the extent of lipid peroxidation and the iron level, while decreasing total antioxidant status, copper, and GSH values. Wi-Fi- and mobile phone-induced EMR may cause precocious puberty and oxidative kidney and testis injury in growing rats

The effects of ventilation with high density oxygen on the strength of gastrointestinal anastomosis

Purpose: The aim of our study is to evaluate the effects of administration of perioperative supplemental oxygen on anastomoses. Methods: Forty male Wistar albino rats were used in the study and randomized into 4 groups. Ischemia-reperfusion models were built in groups 3 and 4. Jejunojejunostomy was performed in all rats and assigned to an oxygen/nitrous oxide mixture with a fraction of inspired oxygen of 30\% in groups 1 and 3 and 80\% in groups 2 and 4. The measurements of perianastomotic tissue oxygen pressure, bursting pressure, level of hydroxyproline were evaluated and compared in all groups. Results: The perianastomotic tissue oxygen pressures, bursting pressures and levels of hydroxyproline were identified as significantly high in groups 2 and 4, administered a fraction of inspired oxygen of 80\%, compared to groups 1 and 3, administered a fraction of inspired oxygen of 30\%. Conclusion: Perioperative supplemental oxygen contributes positively to the anastomotic healing

Is pin configuration the only factor causing loss of reduction in the management of pediatric type III supracondylar fractures?

Objective: Closed reduction with percutaneous pinning is the treatment of choice for displaced supracondylar humerus fractures in children. In addition to configuration of pin fixation, many factors have been attributed to loss of reduction (LOR). The aim of the present study was to review potential factors that contribute to loss of reduction in the closed management of type III pediatric supracondylar fractures. Methods: Treatment of 87 patients with type III supracondylar fractures was reviewed to determine factors associated with loss of reduction; 48 patients were treated with lateral pinning and 39 with crossed-pinning after closed reduction. Outcome parameters included radiographic maintenance of postoperative reduction. Results: Lateral or crossed-pin configuration, pin spread at fracture site, pin-spread ratio (PSR), and direction of coronal displacement of the fracture were not associated with LOR. A significant difference (p = 0.01) was found between LOR rates of patients with medial wall communication and LOR. Conclusion: Medial wall communication is a contributing factor to LOR in the management of type III supracondylar fractures. Cross-pinning should be preferred when medial wall communication is present, to provide more stable fixation. Level of evidence: Level IV, Therapeutic study. Keywords: Fracture, Loss of reduction, Supracondylar humerus, Pin configuratio