1,356 research outputs found

    anomalyDetection: Implementation of Augmented Network Log Anomaly Detection Procedures

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    As the number of cyber-attacks continues to grow on a daily basis, so does the delay in threat detection. For instance, in 2015, the Office of Personnel Management discovered that approximately 21.5 million individual records of Federal employees and contractors had been stolen. On average, the time between an attack and its discovery is more than 200 days. In the case of the OPM breach, the attack had been going on for almost a year. Currently, cyber analysts inspect numerous potential incidents on a daily basis, but have neither the time nor the resources available to perform such a task. anomalyDetection aims to curtail the time frame in which anomalous cyber activities go unnoticed and to aid in the efficient discovery of these anomalous transactions among the millions of daily logged events by i) providing an efficient means for pre-processing and aggregating cyber data for analysis by employing a tabular vector transformation and handling multicollinearity concerns; ii) offering numerous built-in multivariate statistical functions such as Mahalanobis distance, factor analysis, principal components analysis to identify anomalous activity, iii) incorporating the pipe operator (%\u3e%) to allow it to work well in the tidyverse workflow. Combined, anomalyDetection offers cyber analysts an efficient and simplified approach to break up network events into time-segment blocks and identify periods associated with suspected anomalies for further evaluation

    Cyber Anomaly Detection: Using Tabulated Vectors and Embedded Analytics for Efficient Data Mining

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    Firewalls, especially at large organizations, process high velocity internet traffic and flag suspicious events and activities. Flagged events can be benign, such as misconfigured routers, or malignant, such as a hacker trying to gain access to a specific computer. Confounding this is that flagged events are not always obvious in their danger and the high velocity nature of the problem. Current work in firewall log analysis is manual intensive and involves manpower hours to find events to investigate. This is predominantly achieved by manually sorting firewall and intrusion detection/prevention system log data. This work aims to improve the ability of analysts to find events for cyber forensics analysis. A tabulated vector approach is proposed to create meaningful state vectors from time-oriented blocks. Multivariate and graphical analysis is then used to analyze state vectors in human–machine collaborative interface. Statistical tools, such as the Mahalanobis distance, factor analysis, and histogram matrices, are employed for outlier detection. This research also introduces the breakdown distance heuristic as a decomposition of the Mahalanobis distance, by indicating which variables contributed most to its value. This work further explores the application of the tabulated vector approach methodology on collected firewall logs. Lastly, the analytic methodologies employed are integrated into embedded analytic tools so that cyber analysts on the front-line can efficiently deploy the anomaly detection capabilities

    Bimatoprost/timolol fixed combination versus latanoprost in treatment-naĂŻve glaucoma patients at high risk of progression: a pilot study.

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    Objective To compare a fixed combination of 0.03% bimatoprost and 0.5% timolol (BTFC) with latanoprost monotherapy (LM) in treatment-naïve patients with open-angle glaucoma (OAG) and risk factors for glaucomatous progression. Methods Patients were enrolled at 15 sites in Spain and Portugal, and were randomized 1:1 to BTFC or LM. Patients instilled one drop of medication once per day at 8 pm for 12 weeks. The primary outcome was change in intraocular pressure (IOP) at 12 weeks. Results Of 81 patients enrolled, 43 were randomized to BTFC and 38 to LM. Mean (SD) change in IOP from baseline to 12 weeks was significantly greater for BTFC than for LM: −13.5 mmHg (4.48) versus −11.4 mmHg (3.19), respectively (P=0.003). Similarly, at 12 weeks, significantly more BTFC patients than LM patients had IOP reductions of ≥40% (74.4% versus 47.4%, P=0.015) or ≥50% (46.5% versus 15.8%, P=0.003). Adverse events were more frequent with BTFC than with LM (33 versus 13 events), but most were mild in severity. The only serious adverse event (colon cancer) was adjudged unrelated to the study medication. Conclusion BTFC was effective and well tolerated in treatment-naïve patients with OAG at high risk of progressio

    Silicon bulk micromachined, symmetric, degenerate vibratorygyroscope, accelerometer and sensor and method for using the same

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    When embodied in a microgyroscope, the invention is comprised of a silicon, four-leaf clover structure with a post attached to the center. The whole structure is suspended by four silicon cantilevers or springs. The device is electrostatically actuated and capacitively detects Coriolis induced motions of the leaves of the leaf clover structure. In the case where the post is not symmetric with the plane of the clover leaves, the device can is usable as an accelerometer. If the post is provided in the shape of a dumb bell or an asymmetric post, the center of gravity is moved out of the plane of clover leaf structure and a hybrid device is provided. When the clover leaf structure is used without a center mass, it performs as a high Q resonator usable as a sensor of any physical phenomena which can be coupled to the resonant performance

    A VSA search for the extended Sunyaev-Zel'dovich Effect in the Corona Borealis Supercluster

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    We present interferometric imaging at 33 GHz of the Corona Borealis supercluster, using the extended configuration of the Very Small Array. A total area of 24 deg^2 has been imaged, with an angular resolution of 11 arcmin and a sensitivity of 12 mJy/beam. The aim of these observations is to search for Sunyaev-Zel'dovich (SZ) detections from known clusters of galaxies in this supercluster and for a possible extended SZ decrement due to diffuse warm/hot gas in the intercluster medium. We measure negative flux values in the positions of the ten richest clusters in the region. Collectively, this implies a 3.0-sigma detection of the SZ effect. In the clusters A2061 and A2065 we find decrements of approximately 2-sigma. Our main result is the detection of two strong and resolved negative features at -70+-12 mJy/beam (-157+-27 microK) and -103+-10 mJy/beam (-230+-23 microK), respectively, located in a region with no known clusters, near the centre of the supercluster. We discuss their possible origins in terms of primordial CMB anisotropies and/or SZ signals related to either unknown clusters or to a diffuse extended warm/hot gas distribution. Our analyses have revealed that a primordial CMB fluctuation is a plausible explanation for the weaker feature (probability of 37.82%). For the stronger one, neither primordial CMB (probability of 0.33%) nor SZ can account alone for its size and total intensity. The most reasonable explanation, then, is a combination of both primordial CMB and SZ signal. Finally, we explore what characteristics would be required for a filamentary structure consisting of warm/hot diffuse gas in order to produce a significant contribution to such a spot taking into account the constraints set by X-ray data.Comment: 16 pages, 10 figures. Accepted in MNRA

    Femoral Neck External Size but not aBMD Predicts Structural and Mass Changes for Women Transitioning Through Menopause

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    The impact of adult bone traits on changes in bone structure and mass during aging is not well understood. Having shown that intracortical remodeling correlates with external size of adult long bones led us to hypothesize that ageâ related changes in bone traits also depend on external bone size. We analyzed hip dualâ energy Xâ ray absorptiometry images acquired longitudinally over 14 years for 198 midlife women transitioning through menopause. The 14â year change in bone mineral content (BMC, R2â =â 0.03, pâ =â 0.015) and bone area (R2â =â 0.13, pâ =â 0.001), but not areal bone mineral density (aBMD, R2â =â 0.00, pâ =â 0.931) correlated negatively with baseline femoral neck external size, adjusted for body size using the residuals from a linear regression between baseline bone area and height. The dependence of the 14â year changes in BMC and bone area on baseline bone area remained significant after adjusting for race/ethnicity, postmenopausal hormone use, the 14â year change in weight, and baseline aBMD, weight, height, and age. Women were sorted into tertiles using the baseline bone areaâ height residuals. The 14â year change in BMC (pâ =â 0.009) and bone area (pâ =â 0.001) but not aBMD (pâ =â 0.788) differed across the tertiles. This suggested that women showed similar changes in aBMD for different structural and biological reasons: women with narrow femoral necks showed smaller changes in BMC but greater increases in bone area compared to women with wide femoral necks who showed greater losses in BMC but without large compensatory increases in bone area. This finding is opposite to expectations that periosteal expansion acts to mechanically offset bone loss. Thus, changes in femoral neck structure and mass during menopause vary widely among women and are predicted by baseline external bone size but not aBMD. How these different structural and mass changes affect individual strengthâ decline trajectories remains to be determined. © 2017 American Society for Bone and Mineral Research.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/137625/1/jbmr3082.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/137625/2/jbmr3082_am.pd

    First results from the Very Small Array -- I. Observational methods

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    The Very Small Array (VSA) is a synthesis telescope designed to image faint structures in the cosmic microwave background on degree and sub-degree angular scales. The VSA has key differences from other CMB interferometers with the result that different systematic errors are expected. We have tested the operation of the VSA with a variety of blank-field and calibrator observations and cross-checked its calibration scale against independent measurements. We find that systematic effects can be suppressed below the thermal noise level in long observations; the overall calibration accuracy of the flux density scale is 3.5 percent and is limited by the external absolute calibration scale.Comment: 9 pages, 10 figures, MNRAS in press (Minor revisions

    Beyond the Planar Limit in ABJM

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    In this article we consider gauge theories with a U(N)X U(N) gauge group. We provide, for the first time, a complete set of operators built from scalar fields that are in the bi fundamental of the two groups. Our operators diagonalize the two point function of the free field theory at all orders in 1/N. We then use this basis to investigate non-planar anomalous dimensions in the ABJM theory. We show that the dilatation operator reduces to a set of decoupled harmonic oscillators, signaling integrability in a nonplanar large N limit.Comment: v2: minor revisison

    A Java Program for LRE-Based Real-Time qPCR that Enables Large-Scale Absolute Quantification

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    Background: Linear regression of efficiency (LRE) introduced a new paradigm for real-time qPCR that enables large-scale absolute quantification by eliminating the need for standard curves. Developed through the application of sigmoidal mathematics to SYBR Green I-based assays, target quantity is derived directly from fluorescence readings within the central region of an amplification profile. However, a major challenge of implementing LRE quantification is the labor intensive nature of the analysis. Findings: Utilizing the extensive resources that are available for developing Java-based software, the LRE Analyzer was written using the NetBeans IDE, and is built on top of the modular architecture and windowing system provided by the NetBeans Platform. This fully featured desktop application determines the number of target molecules within a sample with little or no intervention by the user, in addition to providing extensive database capabilities. MS Excel is used to import data, allowing LRE quantification to be conducted with any real-time PCR instrument that provides access to the raw fluorescence readings. An extensive help set also provides an in-depth introduction to LRE, in addition to guidelines on how to implement LRE quantification. Conclusions: The LRE Analyzer provides the automated analysis and data storage capabilities required by large-scale qPCR projects wanting to exploit the many advantages of absolute quantification. Foremost is the universal perspective afforded by absolute quantification, which among other attributes, provides the ability to directly compare quantitative data produced by different assays and/or instruments. Furthermore, absolute quantification has important implications for gene expression profiling in that it provides the foundation for comparing transcript quantities produced by any gene with any other gene, within and between samples

    Cerebral protection in homozygous null ICAM-1 mice after middle cerebral artery occlusion. Role of neutrophil adhesion in the pathogenesis of stroke.

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    This is the published version. Copyright 1996 American Society for Clinical Research.Acute neutrophil (PMN) recruitment to postischemic cardiac or pulmonary tissue has deleterious effects in the early reperfusion period, but the mechanisms and effects of neutrophil influx in the pathogenesis of evolving stroke remain controversial. To investigate whether PMNs contribute to adverse neurologic sequelae and mortality after stroke, and to study the potential role of the leukocyte adhesion molecule intercellular adhesion molecule-1 (ICAM-1) in the pathogenesis of stroke, we used a murine model of transient focal cerebral ischemia consisting of intraluminal middle cerebral artery occlusion for 45 min followed by 22 h of reperfusion. PMN accumulation, monitored by deposition of 111In-labeled PMNs in postischemic cerebral tissue, was increased 2.5-fold in the ipsilateral (infarcted) hemisphere compared with the contralateral (noninfarcted) hemisphere (P < 0.01). Mice immunodepleted of neutrophils before surgery demonstrated a 3.0-fold reduction in infarct volumes (P < 0.001), based on triphenyltetrazolium chloride staining of serial cerebral sections, improved ipsilateral cortical cerebral blood flow (measured by laser Doppler), and reduced neurological deficit compared with controls. In wild-type mice subjected to 45 min of ischemia followed by 22 h of reperfusion, ICAM-1 mRNA was increased in the ipsilateral hemisphere, with immunohistochemistry localizing increased ICAM-1 expression on cerebral microvascular endothelium. The role of ICAM-1 expression in stroke was investigated in homozygous null ICAM-1 mice (ICAM-1 -/-) in comparison with wild-type controls (ICAM-1 +/+). ICAM-1 -/- mice demonstrated a 3.7-fold reduction in infarct volume (P < 0.005), a 35% increase in survival (P < 0.05), and reduced neurologic deficit compared with ICAM-1 +/+ controls. Cerebral blood flow to the infarcted hemisphere was 3.1-fold greater in ICAM-1 -/- mice compared with ICAM-1 +/+ controls (P < 0.01), suggesting an important role for ICAM-1 in the genesis of postischemic cerebral no-reflow. Because PMN-depleted and ICAM-1-deficient mice are relatively resistant to cerebral ischemia-reperfusion injury, these studies suggest an important role for ICAM-1-mediated PMN adhesion in the pathophysiology of evolving stroke
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