Sample records for attack perform trial

  1. Interpersonal coordination tendencies shape 1-vs-1 sub-phase performance outcomes in youth soccer.

    PubMed

    Duarte, Ricardo; Araújo, Duarte; Davids, Keith; Travassos, Bruno; Gazimba, Vítor; Sampaio, Jaime

    2012-05-01

    This study investigated the influence of interpersonal coordination tendencies on performance outcomes of 1-vs-1 sub-phases in youth soccer. Eight male developing soccer players (age: 11.8 ± 0.4 years; training experience: 3.6 ± 1.1 years) performed an in situ simulation of a 1-vs-1 sub-phase of soccer. Data from 82 trials were obtained with motion-analysis techniques, and relative phase used to measure the space-time coordination tendencies of attacker-defender dyads. Approximate entropy (ApEn) was then used to quantify the unpredictability of interpersonal interactions over trials. Results revealed how different modes of interpersonal coordination emerging from attacker-defender dyads influenced the 1-vs-1 performance outcomes. High levels of space-time synchronisation (47%) and unpredictability in interpersonal coordination processes (ApEn: 0.91 ± 0.34) were identified as key features of an attacking player's success. A lead-lag relation attributed to a defending player (34% around -30° values) and a more predictable coordination mode (ApEn: 0.65 ± 0.27, P < 0.001), demonstrated the coordination tendencies underlying the success of defending players in 1-vs-1 sub-phases. These findings revealed how the mutual influence of each player on the behaviour of dyadic systems shaped emergent performance outcomes. More specifically, the findings showed that attacking players should be constrained to exploit the space-time synchrony with defenders in an unpredictable and creative way, while defenders should be encouraged to adopt postures and behaviours that actively constrain the attacker's actions.

  2. A selected controlled trial of supplementary vitamin E for treatment of muscle cramps in hemodialysis patients.

    PubMed

    El-Hennawy, Adel S; Zaib, Salwat

    2010-01-01

    Muscle cramps are not uncommon complications of hemodialysis (HD) treatments and lead to early termination of HD sessions and are therefore a significant cause of under-dialysis. The etiology of cramps in dialysis patients remains a matter of debate. Many reports suggested that vitamin E (vit. E) may be effective for the prevention of HD-associated cramps. We decided to perform a selected controlled trial of supplementary vit. E for treatment of patients on HD who experience frequent attacks during and between HD sessions. The goal was to compare the number of attacks of muscle cramps with the patient's baseline over a specific period of time. In this study, 19 HD patients were randomly selected of different age groups and ethnicity. Patient must have had at least 60 attacks of muscle cramps during and between HD sessions over a 12-week period. All selected patients received vit. E at a dose of 400 international units daily for 12 weeks, and the number of attacks of muscle cramps was recorded. The frequency of muscle cramps decreased significantly during vit. E therapy, and, at the end of the trial, vit. E led to cramp reductions of 68.3%. The reduction in number of attacks of muscle cramps had no significant correlation with age, sex, etiology of end-stage renal disease, serum electrolytes, or HD duration, and it showed a statistically positive correlation (P = 0.0001) with vit. E therapy. No vit. E-related adverse effects were encountered during the trial. Short-term treatment with vit. E is safe and effective in reducing number of attacks of muscle cramps in HD patients, as shown in our study.

  3. Aircrew Training Devices: Fidelity Features.

    DTIC Science & Technology

    1981-01-01

    providing artificial cues for glideslope and lineup . He found that an adaptive strategy for using augmenting cues, where the presence or absence of the...with continuously available sources of augmented information for lineup and glideslope in the simulatot, they performed more poorly on test trials...flown: fighting wing, barrel roll attack, sequential attack, free engagement, aileron roll and loop. Results indicated higher ratings of realism for

  4. Angular relationships regulate coordination tendencies of performers in attacker-defender dyads in team sports.

    PubMed

    Esteves, Pedro T; Araújo, Duarte; Vilar, Luís; Travassos, Bruno; Davids, Keith; Esteves, Carlos

    2015-04-01

    This study examined the continuous interpersonal interactions of performers in dyadic systems in team sports, as a function of changing information constraints. As a task vehicle, we investigated how attackers attained success in 1v1 sub-phases of basketball by exploring angular relations with immediate opponents and the basket. We hypothesized that angular relations would convey information for the attackers to dribble past defenders. Four basketball players performed as an attacker and defender in 1v1 sub-phases of basketball, in which the co-positioning and orientation of participants relative to the basket was manipulated. After video recording performance behaviors, we digitized participant movement displacement trajectories and categorized trials as successful or unsuccessful (from the attackers' viewpoint). Results revealed that, to successfully dribble past a defender, attackers tended to explore the left hand side of the space by defenders by increasing their angular velocity and decreasing their angular variability, especially in the center of the court. Interpersonal interactions and goal-achievement in attacker-defender dyads appear to have been constrained by the angular relations sustained between participants relative to the scoring target. Results revealed the functionality of exploratory behaviors of participants attempting re-align spatial relations with an opponent in 1v1 sub-phases of team games. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Analysis of characteristics associated with reinjection of icatibant: Results from the icatibant outcome survey.

    PubMed

    Longhurst, Hilary J; Aberer, Werner; Bouillet, Laurence; Caballero, Teresa; Fabien, Vincent; Zanichelli, Andrea; Maurer, Marcus

    2015-01-01

    Phase 3 icatibant trials showed that most hereditary angioedema (HAE) (C1 inhibitor deficiency) acute attacks were treated successfully with one injection of icatibant, a selective bradykinin B2 receptor antagonist. We conducted a post hoc analysis of icatibant reinjection for HAE type I and II attacks in a real-world setting by using data from the Icatibant Outcome Survey, an ongoing observational study that monitors the safety and effectiveness of icatibant treatment. Descriptive retrospective analyses of icatibant reinjection were performed on Icatibant Outcome Survey data (February 2008 to December 2012). New attacks were defined as the onset of new symptoms after full resolution of the previous attack. Potential associations between the patient and attack characteristics and reinjection were explored by using logistic regression analysis. Icatibant was administered for 652 attacks in 170 patients with HAE type I or II. Most attacks (89.1%) were treated with a single icatibant injection. For attacks that required two or three injections, the second injection was given a median of 11.0 hours after the first injection, with 90.4% of second injections administered ≥6 hours after the first injection. Time to resolution and attack duration were significantly longer for two or three injections versus one icatibant injection (p < 0.0001 and p < 0.05, respectively). Multivariate logistic regression analysis identified sex, attack severity, and laryngeal attacks as significantly correlated with reinjection (all p ≤ 0.05). These factors did not remain predictors for reinjection when two outlier patients with distinct patterns of icatibant use were excluded. In this real-world setting, most HAE attacks resolved with one icatibant injection. There was no distinct profile for patients or attacks that required reinjection when outliers with substantially different patterns of use were excluded. Because new attacks were not distinguished from the recurrence of symptoms, reinjection rates may be slightly higher than shown here. Clinical trial identifier: NCT01034969.

  6. Problem solving ability of Octopus vulgaris Lamarck (Mollusca, Cephalopoda).

    PubMed

    Fiorito, G; von Planta, C; Scotto, P

    1990-03-01

    Experiments presented in this study show that Octopus vulgaris Lamarck is able to open transparent glass jars closed with a plastic plug and containing a live crab (Carcinus mediterraneus). The animals remove the plus (Operandum: O) and seize the crab (Predation :P) in one single attack. The number of unsuccessful attacks appears to decrease over a series of trials (p less than .01); during the same period exploration time remains unchanged. There is a statistically significant increase in performance over trials for O (p less than .01) and P (p less than .05) mean times analyzed by single factor ANOVA, suggesting that the learning process is accomplished either by stimulus-response association or by trial and error. We propose that Octopus vulgaris is capable of learning the solutions of both problems, Operandum and Predation, thus showing a highly developed ability of "integration" of the behavioral program.

  7. Privacy in Pharmacogenetics: An End-to-End Case Study of Personalized Warfarin Dosing.

    PubMed

    Fredrikson, Matthew; Lantz, Eric; Jha, Somesh; Lin, Simon; Page, David; Ristenpart, Thomas

    2014-08-01

    We initiate the study of privacy in pharmacogenetics, wherein machine learning models are used to guide medical treatments based on a patient's genotype and background. Performing an in-depth case study on privacy in personalized warfarin dosing, we show that suggested models carry privacy risks, in particular because attackers can perform what we call model inversion : an attacker, given the model and some demographic information about a patient, can predict the patient's genetic markers. As differential privacy (DP) is an oft-proposed solution for medical settings such as this, we evaluate its effectiveness for building private versions of pharmacogenetic models. We show that DP mechanisms prevent our model inversion attacks when the privacy budget is carefully selected . We go on to analyze the impact on utility by performing simulated clinical trials with DP dosing models. We find that for privacy budgets effective at preventing attacks, patients would be exposed to increased risk of stroke, bleeding events, and mortality . We conclude that current DP mechanisms do not simultaneously improve genomic privacy while retaining desirable clinical efficacy, highlighting the need for new mechanisms that should be evaluated in situ using the general methodology introduced by our work.

  8. Privacy in Pharmacogenetics: An End-to-End Case Study of Personalized Warfarin Dosing

    PubMed Central

    Fredrikson, Matthew; Lantz, Eric; Jha, Somesh; Lin, Simon; Page, David; Ristenpart, Thomas

    2014-01-01

    We initiate the study of privacy in pharmacogenetics, wherein machine learning models are used to guide medical treatments based on a patient’s genotype and background. Performing an in-depth case study on privacy in personalized warfarin dosing, we show that suggested models carry privacy risks, in particular because attackers can perform what we call model inversion: an attacker, given the model and some demographic information about a patient, can predict the patient’s genetic markers. As differential privacy (DP) is an oft-proposed solution for medical settings such as this, we evaluate its effectiveness for building private versions of pharmacogenetic models. We show that DP mechanisms prevent our model inversion attacks when the privacy budget is carefully selected. We go on to analyze the impact on utility by performing simulated clinical trials with DP dosing models. We find that for privacy budgets effective at preventing attacks, patients would be exposed to increased risk of stroke, bleeding events, and mortality. We conclude that current DP mechanisms do not simultaneously improve genomic privacy while retaining desirable clinical efficacy, highlighting the need for new mechanisms that should be evaluated in situ using the general methodology introduced by our work. PMID:27077138

  9. Thermal acclimation of interactions: differential responses to temperature change alter predator-prey relationship.

    PubMed

    Grigaltchik, Veronica S; Ward, Ashley J W; Seebacher, Frank

    2012-10-07

    Different species respond differently to environmental change so that species interactions cannot be predicted from single-species performance curves. We tested the hypothesis that interspecific difference in the capacity for thermal acclimation modulates predator-prey interactions. Acclimation of locomotor performance in a predator (Australian bass, Macquaria novemaculeata) was qualitatively different to that of its prey (eastern mosquitofish, Gambusia holbrooki). Warm (25°C) acclimated bass made more attacks than cold (15°C) acclimated fish regardless of acute test temperatures (10-30°C), and greater frequency of attacks was associated with increased prey capture success. However, the number of attacks declined at the highest test temperature (30°C). Interestingly, escape speeds of mosquitofish during predation trials were greater than burst speeds measured in a swimming arena, whereas attack speeds of bass were lower than burst speeds. As a result, escape speeds of mosquitofish were greater at warm temperatures (25°C and 30°C) than attack speeds of bass. The decline in the number of attacks and the increase in escape speed of prey means that predation pressure decreases at high temperatures. We show that differential thermal responses affect species interactions even at temperatures that are within thermal tolerance ranges. This thermal sensitivity of predator-prey interactions can be a mechanism by which global warming affects ecological communities.

  10. Thermal acclimation of interactions: differential responses to temperature change alter predator–prey relationship

    PubMed Central

    Grigaltchik, Veronica S.; Ward, Ashley J. W.; Seebacher, Frank

    2012-01-01

    Different species respond differently to environmental change so that species interactions cannot be predicted from single-species performance curves. We tested the hypothesis that interspecific difference in the capacity for thermal acclimation modulates predator–prey interactions. Acclimation of locomotor performance in a predator (Australian bass, Macquaria novemaculeata) was qualitatively different to that of its prey (eastern mosquitofish, Gambusia holbrooki). Warm (25°C) acclimated bass made more attacks than cold (15°C) acclimated fish regardless of acute test temperatures (10–30°C), and greater frequency of attacks was associated with increased prey capture success. However, the number of attacks declined at the highest test temperature (30°C). Interestingly, escape speeds of mosquitofish during predation trials were greater than burst speeds measured in a swimming arena, whereas attack speeds of bass were lower than burst speeds. As a result, escape speeds of mosquitofish were greater at warm temperatures (25°C and 30°C) than attack speeds of bass. The decline in the number of attacks and the increase in escape speed of prey means that predation pressure decreases at high temperatures. We show that differential thermal responses affect species interactions even at temperatures that are within thermal tolerance ranges. This thermal sensitivity of predator–prey interactions can be a mechanism by which global warming affects ecological communities. PMID:22859598

  11. Patent foramen ovale and migraine attacks: a systematic review.

    PubMed

    Lip, Philomena Z Y; Lip, Gregory Y H

    2014-05-01

    Migraine headache and the presence of a patent foramen ovale have been associated with each other, although the precise pathophysiological mechanism(s) are uncertain. The purpose of this systematic review was to identify the extent of patent foramen ovale prevalence in migraineurs and to determine whether closure of a patent foramen ovale would improve migraine headache. An electronic literature search was performed to select studies between January 1980 and February 2013 that were relevant to the prevalence of patent foramen ovale and migraine, and the effects of intervention(s) on migraine attacks. Of the initial 368 articles presented by the initial search, 20 satisfied the inclusion criteria assessing patent foramen ovale prevalence in migraineurs and 21 presented data on patent foramen ovale closure. In case series and cohort studies, patent foramen ovale prevalence in migraineurs ranged from 14.6% to 66.5%. Case-control studies reported a prevalence ranging from 16.0% to 25.7% in controls, compared with 26.8% to 96.0% for migraine with aura. The extent of improvement or resolution of migraine headache attack symptoms was variable. In case series, intervention ameliorated migraine headache attack in 13.6% to 92.3% of cases. One single randomized trial did not show any benefit from patent foramen ovale closure. The data overall do not exclude the possibility of a placebo effect for resolving migraine following patent foramen ovale closure. This systematic review demonstrates firstly that migraine headache attack is associated with a higher prevalence of patent foramen ovale than among the general population. Observational data suggest that some improvement of migraine would be observed if the patent foramen ovale were to be closed. A proper assessment of any interventions for patent foramen ovale closure would require further large randomized trials to be conducted given uncertainties from existing trial data. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Specialised use of working memory by Portia africana, a spider-eating salticid.

    PubMed

    Cross, Fiona R; Jackson, Robert R

    2014-03-01

    Using expectancy-violation methods, we investigated the role of working memory in the predatory strategy of Portia africana, a salticid spider from Kenya that preys by preference on other spiders. One of this predator's tactics is to launch opportunistic leaping attacks on to other spiders in their webs. Focussing on this particular tactic, our experiments began with a test spider on a ramp facing a lure (dead prey spider mounted on a cork disc) that could be reached by leaping. After the test spider faced the lure for 30 s, we blocked the test spider's view of the lure by lowering an opaque shutter before the spider leapt. When the shutter was raised 90 s later, either the same lure came into view again (control) or a different lure came into view (experimental: different prey type in same orientation or same prey type in different orientation). We recorded attack frequency (number of test spiders that leapt at the lure) and attack latency (time elapsing between shutter being raised and spiders initiating a leap). Attack latencies in control trials were not significantly different from attack latencies in experimental trials, regardless of whether it was prey type or prey orientation that changed in the experimental trials. However, compared with test spiders in the no-change control trials, significantly fewer test spiders leapt when prey type changed. There was no significant effect on attack frequency when prey orientation changed. These findings suggest that this predator represents prey type independently of prey orientation.

  13. The use of verbenone to protect whitebark pine from mountain pine beetle

    Treesearch

    Sandra Kegley; Ken Gibson

    2011-01-01

    Verbenone is a known anti-aggregation pheromone of mountain pine beetle (MPB), Dendroctonus ponderosae Hopkins, and has been tested in protecting susceptible host trees from attack since 1988. Inconsistent performance of verbenone during field trials caused formulations and release devices to change through time, resulting in three products currently registered with...

  14. Nitrates for stable angina: a systematic review and meta-analysis of randomized clinical trials.

    PubMed

    Wei, Jiafu; Wu, Taixiang; Yang, Qing; Chen, Mao; Ni, Juan; Huang, Dejia

    2011-01-07

    To assess the effect (harms and benefits) of nitrates for stable angina. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and EMBASE. Randomized controlled trials with both parallel and crossover design were included. The following outcome measures were evaluated: number of angina attacks weekly and nitroglycerin consumption, quality of life, total exercise duration, time to onset of angina and time to 1 mm ST depression. Fifty-one trials with 3595 patients meeting inclusion criteria were analyzed. Both intermittent and continuous regimens of nitrates lengthened exercise duration significantly by 31 and 53 s respectively. The number of angina attacks was significantly reduced by 2.89 episodes weekly for continuous administration and 1.5 episodes weekly for intermittent administration. With intermittent administration, increased dose provided with 21 s more length of exercise duration. With continuous administration, exercise duration was pronged more in low-dose group. Quality of life was not improved by continuous application of GTN patches and was similar between continuous and intermittent groups. In addition, 51.6% patients receiving nitrates complained with headache. Long-term administration of nitrates was beneficial for angina prophylaxis and improved exercise performance but might be ineffective for improving quality of life. With continuous regimen, low-dose nitrates were more effective than high-dose ones for improving exercise performance. By contrast, with intermittent regimen, high-dose nitrates were more effective. In addition, intermittent administration could bring zero-hour effect. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  15. Using Bayesian Adaptive Trial Designs for Comparative Effectiveness Research: A Virtual Trial Execution.

    PubMed

    Luce, Bryan R; Connor, Jason T; Broglio, Kristine R; Mullins, C Daniel; Ishak, K Jack; Saunders, Elijah; Davis, Barry R

    2016-09-20

    Bayesian and adaptive clinical trial designs offer the potential for more efficient processes that result in lower sample sizes and shorter trial durations than traditional designs. To explore the use and potential benefits of Bayesian adaptive clinical trial designs in comparative effectiveness research. Virtual execution of ALLHAT (Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial) as if it had been done according to a Bayesian adaptive trial design. Comparative effectiveness trial of antihypertensive medications. Patient data sampled from the more than 42 000 patients enrolled in ALLHAT with publicly available data. Number of patients randomly assigned between groups, trial duration, observed numbers of events, and overall trial results and conclusions. The Bayesian adaptive approach and original design yielded similar overall trial conclusions. The Bayesian adaptive trial randomly assigned more patients to the better-performing group and would probably have ended slightly earlier. This virtual trial execution required limited resampling of ALLHAT patients for inclusion in RE-ADAPT (REsearch in ADAptive methods for Pragmatic Trials). Involvement of a data monitoring committee and other trial logistics were not considered. In a comparative effectiveness research trial, Bayesian adaptive trial designs are a feasible approach and potentially generate earlier results and allocate more patients to better-performing groups. National Heart, Lung, and Blood Institute.

  16. Detection of Ammonium Nitrate Variants by Canine: A Study of Generalization between Like Substances

    DTIC Science & Technology

    2018-04-30

    PERFORMING ORGANIZATION REPORT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 10. SPONSOR / MONITOR’S ACRONYM(S)9. SPONSORING / MONITORING...16 Figure 9. Alert rates for Group A, trained to prill fertilizer AN, and Group B, trained to ground fertilizer AN for Trial 2...thirds of all American deaths in combat were by IED attacks, according to the Joint IED Defeat Organization (JIEDDO, now the Joint Improvised- Threat

  17. A randomized double-blind, placebo-controlled, cross-over trial (Vestparoxy) of the treatment of vestibular paroxysmia with oxcarbazepine.

    PubMed

    Bayer, Otmar; Brémová, Tatiana; Strupp, Michael; Hüfner, Katharina

    2018-02-01

    Vestibular paroxysmia (VP) is characterized by short, often oligosymptomatic attacks of vertigo which occur spontaneously or are sometimes provoked by turning the head. Despite the description of the disease almost 40 years ago (first termed "disabling positional vertigo"), no controlled treatment trial has been published to date. The Vestparoxy trial was designed as a randomized, placebo-controlled, double-blind cross-over trial to examine the therapeutic effect of oxcarbazepine (OXA) in patients with definite or probable VP. Patients were recruited from August 2005 to December 2011 in the outpatient Dizziness Unit of the Department of Neurology of the Munich University Hospital, and randomized to receive OXA (first week: 300 mg once per day, second week: 300 mg b.i.d., third week: 300 mg t.i.d. until the end of the third month), followed by placebo or vice versa with a 1-month wash-out period in between. The primary endpoint was the number of days with one or more attacks. Secondary endpoints were the number of attacks during the observed days, and the median (for each day) duration of attacks. All these endpoints were assessed using standardized diaries collected at the end of each treatment phase. Forty-three patients were randomized, 18 patients provided usable data (2525 patient days) for at least one treatment phase and were included in the main (intention-to-treat) analysis. The most common reasons for discontinuation documented were adverse events. The risk of experiencing a day with at least one attack was 0.41 under OXA, and 0.62 under placebo treatment, yielding a relative risk of 0.67 (95% CI 0.47-0.95, p = 0.025). The number of attacks during the observed days ratio was 0.53 (95% CI 0.42-0.68, p < 0.001) under OXA compared to placebo. Median attack duration was 4 s (Q25: 2 s, Q75: 120 s) under OXA, and 3 s (Q25: 2 s, Q75: 60 s) under placebo treatment. When days with no attacks, i.e., duration = 0, were included in the analysis, these figures changed to 0 (Q25: 0, Q75: 3 s), and 2 (Q25: 0, Q75: 6 s). No serious adverse events or new safety findings were identified during the trial. The Vestparoxy trial showed a significant reduction of VP attacks under OXA compared to placebo treatment, confirming the known and revealing no new side effects.

  18. Complexing agents and pH influence on chemical durability of type I moulded glass containers.

    PubMed

    Biavati, Alberto; Poncini, Michele; Ferrarini, Arianna; Favaro, Nicola; Scarpa, Martina; Vallotto, Marta

    2017-06-16

    Among the factors that affect the glass surface chemical durability, pH and complexing agents presence in aqueous solution have the main role (1). Glass surface attack can be also related to the delamination issue with glass particles appearance in the pharmaceutical preparation. A few methods to check for glass containers delamination propensity and some control guidelines have been proposed (2,3). The present study emphasizes the possible synergy between a few complexing agents with pH on the borosilicate glass chemical durability. Hydrolytic attack was performed in small volume 23 ml type I glass containers autoclaved according to EP or USP for 1 hour at 121°C, in order to enhance the chemical attack due to time, temperature and the unfavourable surface/volume ratio. 0,048 M or 0.024 M (moles/liter) solutions of the acids citric, glutaric, acetic, EDTA (ethylenediaminetetraacetic acid) and sodium phosphate with water for comparison, were used for the trials. The pH was adjusted ± 0,05 units at fixed values 5,5-6,6-7-7,4-8-9 by LiOH diluted solution. Since silicon is the main glass network former, silicon release into the attack solutions was chosen as the main index of the glass surface attack and analysed by ICPAES. The work was completed by the analysis of the silicon release in the worst attack conditions, of moulded glass, soda lime type II and tubing borosilicate glass vials to compare different glass compositions and forming technologies. Surface analysis by SEM was finally performed to check for the surface status after the worst chemical attack condition by citric acid. Copyright © 2017, Parenteral Drug Association.

  19. Efficacy and safety of betahistine treatment in patients with Meniere’s disease: primary results of a long term, multicentre, double blind, randomised, placebo controlled, dose defining trial (BEMED trial)

    PubMed Central

    Adrion, Christine; Fischer, Carolin Simone; Wagner, Judith; Gürkov, Robert; Mansmann, Ulrich

    2016-01-01

    Study question What is the long term efficacy of betahistine dihydrochloride on the incidence of vertigo attacks in patients with Meniere’s disease, compared with placebo? Methods The BEMED trial is a multicentre, double blind, randomised, placebo controlled, three arm, parallel group, phase III, dose defining superiority trial conducted in 14 German tertiary referral centres (for neurology or ear, nose, and throat). Adults aged 21-80 years (mean age 56 years) with definite unilateral or bilateral Meniere’s disease were recruited from March 2008 to November 2012. Participants received placebo (n=74), low dose betahistine (2×24 mg daily, (n=73)), or high dose betahistine (3×48 mg daily, (n=74)) over nine months. The primary outcome was the number of attacks per 30 days, based on patients’ diaries during a three month assessment period at months seven to nine. An internet based randomisation schedule performed a concealed 1:1:1 allocation, stratified by study site. Secondary outcomes included the duration and severity of attacks, change in quality of life scores, and several observer-reported parameters to assess changes in audiological and vestibular function. Study answer and limitations Incidence of attacks related to Meniere’s disease did not differ between the three treatment groups (P=0.759). Compared with placebo, attack rate ratios were 1.036 (95% confidence interval 0.942 to 1.140) and 1.012 (0.919 to 1.114) for low dose and high dose betahistine, respectively. The overall monthly attack rate fell significantly by the factor 0.758 (0.705 to 0.816; P<0.001). The population based, mean monthly incidence averaged over the assessment period was 2.722 (1.304 to 6.309), 3.204 (1.345 to 7.929), and 3.258 (1.685 to 7.266) for the placebo, low dose betahistine, and high dose betahistine groups, respectively. Results were consistent for all secondary outcomes. Treatment was well tolerated with no unexpected safety findings. Without a control group of patients who did not receive any intervention to follow the natural course of the disease, the placebo effect could not be accurately assessed and differentiated from spontaneous remission and fluctuation of symptoms. What this study adds Current evidence is limited as to whether betahistine prevents vertigo attacks caused by Meniere’s disease, compared with placebo. The trial provides information on symptom relief on placebo intervention which is relevant for the design of future studies on potential disease modifying treatments in patients with Meniere’s disease. Funding, competing interests, data sharing Support from the German Federal Ministry of Education and Research (BMBF support code 01KG0708). Potential competing interests have been reported in full at the end of the paper on thebmj.com. Data are available from the corresponding author (Michael.Strupp@med.uni-muenchen.de) or biostatistician (mansmann@ibe.med.uni-muenchen.de). Study registration EudraCT no 2005-000752-32; ISRCTN no ISRCTN44359668. PMID:26797774

  20. Patent Foramen Ovale Closure for Secondary Prevention of Cryptogenic Stroke: Updated Meta-Analysis of Randomized Clinical Trials.

    PubMed

    Vaduganathan, Muthiah; Qamar, Arman; Gupta, Ankur; Bajaj, Navkaranbir; Golwala, Harsh B; Pandey, Ambarish; Bhatt, Deepak L

    2018-05-01

    Patent foramen ovale closure represents a potential secondary prevention strategy for cryptogenic stroke, but available trials have varied by size, device studied, and follow-up. We conducted a systematic search of published randomized clinical trials evaluating patent foramen ovale closure versus medical therapy in patients with recent stroke or transient ischemic attack using PubMED, EMBASE, and Cochrane through September 2017. Weighting was by random effects models. Of 480 studies screened, we included 5 randomized clinical trials in the meta-analysis in which 3440 patients were randomized to patent foramen ovale closure (n = 1829) or medical therapy (n = 1611) and followed for an average of 2.0 to 5.9 years. Index stroke/transient ischemic attack occurred within 6 to 9 months of randomization. The primary end point was composite stroke/transient ischemic attack and death (in 3 trials) or stroke alone (in 2 trials). Patent foramen ovale closure reduced the primary end point (0.70 vs 1.48 events per 100 patient-years; risk ratio [RR], 0.52 [0.29-0.91]; I 2  = 55.0%) and stroke/transient ischemic attack (1.04 vs 2.00 events per 100 patient-years; RR, 0.55 [0.37-0.82]; I 2  = 42.2%) with modest heterogeneity compared with medical therapy. Procedural bleeding was not different between study arms (1.8% vs 1.8%; RR, 0.94 [0.49-1.83]; I 2  = 29.2%), but new-onset atrial fibrillation/flutter was increased with patent foramen ovale closure (6.6% vs 0.7%; RR, 4.69 [2.17-10.12]; I 2  = 29.3%). In patients with recent cryptogenic stroke, patent foramen ovale closure reduces recurrent stroke/transient ischemic attack compared with medical therapy, but is associated with a higher risk of new-onset atrial fibrillation/flutter. Copyright © 2018 Elsevier Inc. All rights reserved.

  1. An avatar based education application to improve patients' knowledge of and response to heart attack symptoms: a pragmatic randomized controlled trial protocol.

    PubMed

    Tongpeth, Jintana; Du, Huiyun; Clark, Robyn

    2018-06-19

    To evaluate the effectiveness of an interactive, avatar based education application to improve knowledge of and response to heart attack symptoms in people who are at risk of a heart attack. Poor knowledge of heart attack symptoms is recognised as a significant barrier to timely medical treatment. Numerous studies have demonstrated that technology can assist in patient education to improve knowledge and self-care. A single-center, non-blinded, two parallel groups, pragmatic randomized controlled trial. Seventy patients will be recruited from the coronary care unit of a public hospital. Eligible participants will be randomised to either the usual care or the intervention group (usual care plus avatar-based heart attack education app). The primary outcome of this study is knowledge. Secondary outcomes include response to heart attack symptoms, health service use and satisfaction. Study participants will be followed-up for six months. This study will evaluate the avatar based education app as a method to deliver vital information to patients. Participants' knowledge of and response to heart attack symptoms, as well as their health service use, will be assessed to evaluate the intervention effectiveness. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  2. Decline in physical performance among women with a recent transient ischemic attack or ischemic stroke: opportunities for functional preservation a report of the Women's Estrogen Stroke Trial.

    PubMed

    Kernan, Walter N; Viscoli, Catherine M; Brass, Lawrence M; Gill, Thomas M; Sarrel, Philip M; Horwitz, Ralph I

    2005-03-01

    Physical performance for walking, reaching, turning, and other common tasks is a major determinant of functional independence after stroke. Current strategies to preserve physical performance focus on prevention of recurrent stroke. Loss of physical performance, however, may occur in the absence of recurrence. To examine this possibility, we measured change in physical performance, independent of subsequent stroke, among women with a recent ischemic stroke or transient ischemic attack (TIA). Among 664 postmenopausal women who participated in a clinical trial of estrogen therapy after stroke or TIA, we administered the Physical Performance Test (PPT) at baseline (mean 58 days from the cerebrovascular event) and annually. Women who died or had a stroke during follow-up were censored. Decline or improvement in physical performance was defined as a change in the PPT score from baseline of at least 3 points. Sustained decline or improvement was defined as 2 consecutive years during which the score had declined or improved, respectively, relative to the baseline score. With each year of follow-up, a smaller proportion of the cohort demonstrated improvement (16% in year 1, 6% in year 5) and a larger proportion demonstrated decline (15% in year 1, 35% in year 5). In an analysis restricted to 259 women with 3 years of follow-up, 46 (18%) experienced a nonsustained decline in physical performance, and 39 (15%) experienced a sustained decline. Decline in physical performance is common after an ischemic stroke or TIA even in the absence of a recurrent neurological event. Our findings suggest that specific interventions to maintain and improve physical performance may be important for reducing long-term disability.

  3. Relationship between clinical variables and cognitive performances in migraineurs with and without aura.

    PubMed

    Le Pira, Francesco; Lanaia, Filippo; Zappalà, Giuseppe; Morana, Rosanna; Panetta, Maria Rosa; Reggio, Ester; Reggio, Arturo

    2004-01-01

    Conflicting data on cognitive defects in migraine could be explained by differences in the clinical variables of the populations studied. We investigated 21 patients with migraine with aura and 24 with migraine without aura, diagnosed according to the International Headache Society criteria. The patients were submitted to a comprehensive battery of neuropsychological tests and grouped according to attack frequency and side of pain. Attack frequency was not associated with significant differences in any of the tasks, while location of pain was found to be significantly related to poorer performance on both the immediate and delayed recall of Rey Complex Figure in migraineurs both with and without aura, and a significant relationship between side of pain and number of clusters in the second trial of California Verbal Learning Test was found only in migraine with aura patients. The finding of worse performances in patients with right-sided pain seems to support a right hemisphere dysfunction hypothesis.

  4. Prevention of Hereditary Angioedema Attacks with a Subcutaneous C1 Inhibitor.

    PubMed

    Longhurst, Hilary; Cicardi, Marco; Craig, Timothy; Bork, Konrad; Grattan, Clive; Baker, James; Li, Huamin H; Reshef, Avner; Bonner, James; Bernstein, Jonathan A; Anderson, John; Lumry, William R; Farkas, Henriette; Katelaris, Constance H; Sussman, Gordon L; Jacobs, Joshua; Riedl, Marc; Manning, Michael E; Hebert, Jacques; Keith, Paul K; Kivity, Shmuel; Neri, Sergio; Levy, Donald S; Baeza, Maria L; Nathan, Robert; Schwartz, Lawrence B; Caballero, Teresa; Yang, William; Crisan, Ioana; Hernandez, María D; Hussain, Iftikhar; Tarzi, Michael; Ritchie, Bruce; Králíčková, Pavlina; Guilarte, Mar; Rehman, Syed M; Banerji, Aleena; Gower, Richard G; Bensen-Kennedy, Debra; Edelman, Jonathan; Feuersenger, Henrike; Lawo, John-Philip; Machnig, Thomas; Pawaskar, Dipti; Pragst, Ingo; Zuraw, Bruce L

    2017-03-23

    Hereditary angioedema is a disabling, potentially fatal condition caused by deficiency (type I) or dysfunction (type II) of the C1 inhibitor protein. In a phase 2 trial, the use of CSL830, a nanofiltered C1 inhibitor preparation that is suitable for subcutaneous injection, resulted in functional levels of C1 inhibitor activity that would be expected to provide effective prophylaxis of attacks. We conducted an international, prospective, multicenter, randomized, double-blind, placebo-controlled, dose-ranging, phase 3 trial to evaluate the efficacy and safety of self-administered subcutaneous CSL830 in patients with type I or type II hereditary angioedema who had had four or more attacks in a consecutive 2-month period within 3 months before screening. We randomly assigned the patients to one of four treatment sequences in a crossover design, each involving two 16-week treatment periods: either 40 IU or 60 IU of CSL830 per kilogram of body weight twice weekly followed by placebo, or vice versa. The primary efficacy end point was the number of attacks of angioedema. Secondary efficacy end points were the proportion of patients who had a response (≥50% reduction in the number of attacks with CSL830 as compared with placebo) and the number of times that rescue medication was used. Of the 90 patients who underwent randomization, 79 completed the trial. Both doses of CSL830, as compared with placebo, reduced the rate of attacks of hereditary angioedema (mean difference with 40 IU, -2.42 attacks per month; 95% confidence interval [CI], -3.38 to -1.46; and mean difference with 60 IU, -3.51 attacks per month; 95% CI, -4.21 to -2.81; P<0.001 for both comparisons). Response rates were 76% (95% CI, 62 to 87) in the 40-IU group and 90% (95% CI, 77 to 96) in the 60-IU group. The need for rescue medication was reduced from 5.55 uses per month in the placebo group to 1.13 uses per month in the 40-IU group and from 3.89 uses in the placebo group to 0.32 uses per month in the 60-IU group. Adverse events (most commonly mild and transient local site reactions) occurred in similar proportions of patients who received CSL830 and those who received placebo. In patients with hereditary angioedema, the prophylactic use of a subcutaneous C1 inhibitor twice weekly significantly reduced the frequency of acute attacks. (Funded by CSL Behring; COMPACT EudraCT number, 2013-000916-10 , and ClinicalTrials.gov number, NCT01912456 .).

  5. Experimental Lung Cancer Drug Shows Early Promise | Poster

    Cancer.gov

    By Frank Blanchard, Staff Writer A first-of-its-kind drug is showing early promise in attacking certain lung cancers that are hard to treat because they build up resistance to conventional chemotherapy. The drug, CO-1686, performed well in a preclinical study involving xenograft and transgenic mice, as reported in the journal Cancer Discovery. It is now being evaluated for safety and efficacy in Phase I and II clinical trials.

  6. Interaction of Insecticide and Media Moisture on Ambrosia Beetle (Coleoptera: Curculionidae) Attacks on Selected Ornamental Trees.

    PubMed

    Frank, Steven D; Anderson, Amanda L; Ranger, Christopher M

    2017-12-08

    Exotic ambrosia beetles, particularly Xylosandrus crassiusculus (Motschulsky) (Coleoptera: Curculionidae: Scolytinae) and Xylosandrus germanus (Blandford) (Coleoptera: Curculionidae: Scolytinae), are among the most damaging pests of ornamental trees in nurseries. Growers have had few tactics besides insecticide applications to reduce ambrosia beetle attacks but recent research has shown that attacks may be reduced by maintaining media moisture below a 50% threshold thereby reducing flood stress. We compared the efficacy of managing media moisture and insecticide applications for reducing ambrosia beetle attacks on three ornamental tree species in North Carolina. During trials in spring 2013 and 2015, flooded Cornus florida and Cornus kousa were heavily attacked despite sprays with permethrin, but nonflooded C. kousa or C. florida were not attacked. In spring 2015 trials, both nonflooded and flooded Styrax japonicus were heavily attacked regardless of permethrin applications. Although ethanol emissions were not measured, the apparently healthy nonflooded S. japonicus trees may have been exposed to an unknown physiological stress, such as low temperature injury, the previous winter, which predisposed them to beetle attack. However, ethanol levels within host tissues were not measured as part of the current study. X. crassiusculus (75%), Xyloborinus saxesenii Ratzburg (13%), and X. germanus (9%) were the most abundant species collected in ethanol baited traps deployed in 2015, while X. crassiusculus (63%) and X. germanus (36%) were the predominant species reared from attacked trees. Results indicate that managing media moisture levels at or below 50%, and maximizing tree health overall, may provide significant protection against Xylosandrus spp. attacks in flood intolerant tree species. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  7. A Novel Mobile Testing Equipment for Rock Cuttability Assessment: Vertical Rock Cutting Rig (VRCR)

    NASA Astrophysics Data System (ADS)

    Yasar, Serdar; Yilmaz, Ali Osman

    2017-04-01

    In this study, a new mobile rock cutting testing apparatus was designed and produced for rock cuttability assessment called vertical rock cutting rig (VRCR) which was designed specially to fit into hydraulic press testing equipment which are available in almost every rock mechanics laboratory. Rock cutting trials were initiated just after the production of VRCR along with calibration of the measuring load cell with an external load cell to validate the recorded force data. Then, controlled rock cutting tests with both relieved and unrelieved cutting modes were implemented on five different volcanic rock samples with a standard simple-shaped wedge tool. Additionally, core cutting test which is an important approach for roadheader performance prediction was simulated with VRCR. Mini disc cutters and point attack tools were used for execution of experimental trials. Results clearly showed that rock cutting tests were successfully realized and measuring system is delicate to rock strength, cutting depth and other variables. Core cutting test was successfully simulated, and it was also shown that rock cutting tests with mini disc cutters and point attack tools are also successful with VRCR.

  8. The efficacy and safety of alprazolam versus other benzodiazepines in the treatment of panic disorder.

    PubMed

    Moylan, Steven; Staples, John; Ward, Stephanie Alison; Rogerson, Jan; Stein, Dan J; Berk, Michael

    2011-10-01

    We performed a meta-analysis of all single- or double-blind, randomized controlled trials comparing alprazolam to another benzodiazepine in the treatment of adult patients meeting the Diagnostic and Statistical Manual of Mental Disorders, Third or Fourth Edition, criteria for panic disorder or agoraphobia with panic attacks. Eight studies met inclusion criteria, describing a total of at least 631 randomized patients. In the pooled results, there were no significant differences in efficacy between alprazolam and the comparator benzodiazepines on any of the prespecified outcomes: improvement in mean panic attack frequency (between-arm weighted mean difference of 0.6 panic attacks per week; 95% confidence interval [CI], -0.3 to 1.6), improvement in Hamilton Anxiety Rating Scale score (weighted mean difference of 0.8 points; 95% CI, -0.5 to 2.1), and proportion of patients free of panic attacks at the final evaluation (pooled relative risk, 1.1; 95% CI, 0.9-1.4). Statistical heterogeneity on prespecified outcomes was not eliminated by stratification on baseline anxiety level. The available evidence fails to demonstrate alprazolam as superior to other benzodiazepines for the treatment of panic disorder.

  9. Treating and preventing influenza in aged care facilities: a cluster randomised controlled trial.

    PubMed

    Booy, Robert; Lindley, Richard I; Dwyer, Dominic E; Yin, Jiehui K; Heron, Leon G; Moffatt, Cameron R M; Chiu, Clayton K; Rosewell, Alexander E; Dean, Anna S; Dobbins, Timothy; Philp, David J; Gao, Zhanhai; MacIntyre, C Raina

    2012-01-01

    Influenza is an important cause of morbidity and mortality for frail older people. Whilst the antiviral drug oseltamivir (a neuraminidase inhibitor) is approved for treatment and prophylaxis of influenza during outbreaks, there have been no trials comparing treatment only (T) versus treatment and prophylaxis (T&P) in Aged Care Facilities (ACFs). Our objective was to compare a policy of T versus T&P for influenza outbreaks in ACFs. We performed a cluster randomised controlled trial in 16 ACFs, that followed a policy of either "T"-oseltamivir treatment (75 mg twice a day for 5 days)-or "T&P"-treatment and prophylaxis (75 mg once a day for 10 days) for influenza outbreaks over three years, in addition to enhanced surveillance. The primary outcome measure was the attack rate of influenza. Secondary outcomes measures were deaths, hospitalisation, pneumonia and adverse events. Laboratory testing was performed to identify the viral cause of influenza-like illness (ILI) outbreaks. The study period 30 June 2006 to 23 December 2008 included three southern hemisphere winters. During that time, influenza was confirmed as the cause of nine of the 23 ILI outbreaks that occurred amongst the 16 ACFs. The policy of T&P resulted in a significant reduction in the influenza attack rate amongst residents: 93/255 (36%) in residents in T facilities versus 91/397 (23%) in T&P facilities (p=0.002). We observed a non-significant reduction in staff: 46/216 (21%) in T facilities versus 47/350 (13%) in T&P facilities (p=0.5). There was a significant reduction in mean duration of outbreaks (T=24 days, T&P=11 days, p=0.04). Deaths, hospitalisations and pneumonia were non-significantly reduced in the T&P allocated facilities. Drug adverse events were common but tolerated. Our trial lacked power but these results provide some support for a policy of "treatment and prophylaxis" with oseltamivir in controlling influenza outbreaks in ACFs. [corrected] Australian Clinical Trials Registry ACTRN12606000278538.

  10. Comparing Asian American Women's Knowledge, Self-Efficacy, and Perceived Risk of Heart Attack to Other Racial and Ethnic Groups: The mPED Trial.

    PubMed

    Fukuoka, Yoshimi; Lisha, Nadra E; Vittinghoff, Eric

    2017-09-01

    The aim of the study was to compare knowledge and awareness of heart attacks/heart disease and perceived risk for future heart attack in Asian/Pacific Islander women, compared to other racial and ethnic groups. In this cross-sectional study, 318 women enrolled in a mobile phone-based physical activity education trial were analyzed. Heart attack knowledge, self-efficacy for recognizing and responding to heart attack symptoms, and perceived risk for a future heart attack were measured. Analyses were conducted using logistic, proportional odds, and linear regression models, depending on the outcome and adjusting for age. Pairwise differences between Asian/Pacific Islanders and the other four groups were assessed using a Bonferroni correction (p < 0.0125). Asian/Pacific Islander women had significantly lower total scores for knowledge of heart attack and self-efficacy for heart attack recognition and care seeking behavior compared to the Caucasian women (p = 0.001 and p = 0.002, respectively). However, perceived risk did not differ among the groups. Forty-six percent of the Asian American women, compared to 25% of Caucasian women, falsely believed "breast cancer is the number one cause of death for women (p = 0.002)." In addition, Asian/Pacific Islander women were less likely to report "arm pain, numbness, tingling, or radiating" as one of the heart attack symptoms compared to the Caucasian and the multiracial group (34%, 63% [p < 0.001], and 66% [p = 0.004], respectively). These findings highlight the urgent need to develop effective, tailored campaigns to close the knowledge gap between Asian/Pacific Islander women and Caucasian women.

  11. Interpersonal dynamics and relative positioning to scoring target of performers in 1 vs. 1 sub-phases of team sports.

    PubMed

    Esteves, Pedro T; Araújo, Duarte; Davids, Keith; Vilar, Luís; Travassos, Bruno; Esteves, Carlos

    2012-01-01

    In this study, we examined the effects of relative positioning of attacker-defender dyads to the basket on interpersonal coordination tendencies in basketball. To achieve this aim, four right-hand dominant basketball players performed in a 1 vs. 1 sub-phase, at nine different playing locations relative to the basket (from 0° to 180°, in 20° increments). Performers' movement displacement trajectories were video-recorded and digitized in 162 trials. Results showed that interpersonal coordination tendencies changed according to the scaling of the relative position of performers to the basket. Stable in-phase modes of coordination were observed between performers' longitudinal and lateral displacements (50.47% and 43.02%) on the left side of the court. On the right side of the court, a shift in the dominant mode of coordination was observed to a defender lead-lag of -30°, both for longitudinal and lateral displacements (30.51% and 32.65%). These results suggest how information about dribbler hand dominance and relative position to the basket may have constrained attacker-defender coordination tendencies in 1 vs. 1 sub-phases of basketball.

  12. Comparative efficacy trial of cupping and serkangabin versus conventional therapy of migraine headaches: A randomized, open-label, comparative efficacy trial.

    PubMed

    Firoozabadi, Mohammad Dehghani; Navabzadeh, Maryam; Roudsari, Mohammad Khodashenas; Zahmatkash, Mohsen

    2014-12-01

    Migraine headaches are the most common acute and recurrent headaches. Current treatment of a migraine headache consists of multiple medications for control and prevention of recurrent attacks. Global emergence of alternative medicine led us to examine the efficacy of cupping therapy plus serkangabin syrup in the treatment of migraine headaches. This study was a randomized, controlled, open-label, comparative efficacy trial. We randomly assigned patients with migraine into cupping therapy plus serkangabin group (30 patients) and conventional treatment group (30 patients). An investigator assessed the severity of headache, frequency of attacks in a week and duration of attacks per hour in 5 visits (at the end of 2 weeks, 1, 3 and 6 months). Generalized estimating equations approach was used to analyze repeated measures data to compare outcomes in both groups. Average age for cupping therapy group and conventional treatment group were 31.7 (±7.6) and 32.6 (±12.7) years, respectively (P = 0.45). After treatment for 2 weeks; and 1, 3 and 6 months, severity of headache (P = 0.80), frequency of migraine attacks (P = 0.63) and duration of attacks per hours (P = 0.48) were similar in conventional and cupping groups but these symptoms were decreased in each group during the study (P < 0.001). There was no significant difference between cupping plus serkangabin therapy and conventional treatment in the treatment and prophylaxis of migraine. The alternative therapy may be used in cases of drug intolerance, no medication response, and in primary care.

  13. Comparative efficacy trial of cupping and serkangabin versus conventional therapy of migraine headaches: A randomized, open-label, comparative efficacy trial

    PubMed Central

    Firoozabadi, Mohammad Dehghani; Navabzadeh, Maryam; Roudsari, Mohammad Khodashenas; Zahmatkash, Mohsen

    2014-01-01

    Background: Migraine headaches are the most common acute and recurrent headaches. Current treatment of a migraine headache consists of multiple medications for control and prevention of recurrent attacks. Global emergence of alternative medicine led us to examine the efficacy of cupping therapy plus serkangabin syrup in the treatment of migraine headaches. Materials and Methods: This study was a randomized, controlled, open-label, comparative efficacy trial. We randomly assigned patients with migraine into cupping therapy plus serkangabin group (30 patients) and conventional treatment group (30 patients). An investigator assessed the severity of headache, frequency of attacks in a week and duration of attacks per hour in 5 visits (at the end of 2 weeks, 1, 3 and 6 months). Generalized estimating equations approach was used to analyze repeated measures data to compare outcomes in both groups. Results: Average age for cupping therapy group and conventional treatment group were 31.7 (±7.6) and 32.6 (±12.7) years, respectively (P = 0.45). After treatment for 2 weeks; and 1, 3 and 6 months, severity of headache (P = 0.80), frequency of migraine attacks (P = 0.63) and duration of attacks per hours (P = 0.48) were similar in conventional and cupping groups but these symptoms were decreased in each group during the study (P < 0.001). Conclusion: There was no significant difference between cupping plus serkangabin therapy and conventional treatment in the treatment and prophylaxis of migraine. The alternative therapy may be used in cases of drug intolerance, no medication response, and in primary care. PMID:25709653

  14. Exposure‐Response Model of Subcutaneous C1‐Inhibitor Concentrate to Estimate the Risk of Attacks in Patients With Hereditary Angioedema

    PubMed Central

    Tortorici, Michael A.; Pawaskar, Dipti; Pragst, Ingo; Machnig, Thomas; Hutmacher, Matthew; Zuraw, Bruce; Cicardi, Marco; Craig, Timothy; Longhurst, Hilary; Sidhu, Jagdev

    2018-01-01

    Subcutaneous C1‐inhibitor (HAEGARDA, CSL Behring), is a US Food and Drug Administration (FDA)‐approved, highly concentrated formulation of a plasma‐derived C1‐esterase inhibitor (C1‐INH), which, in the phase III Clinical Studies for Optimal Management in Preventing Angioedema with Low‐Volume Subcutaneous C1‐inhibitor Replacement Therapy (COMPACT) trial, reduced the incidence of hereditary angioedema (HAE) attacks when given prophylactically. Data from the COMPACT trial were used to develop a repeated time‐to‐event model to characterize the timing and frequency of HAE attacks as a function of C1‐INH activity, and then develop an exposure–response model to assess the relationship between C1‐INH functional activity levels (C1‐INH(f)) and the risk of an attack. The C1‐INH(f) values of 33.1%, 40.3%, and 63.1% were predicted to correspond with 50%, 70%, and 90% reductions in the HAE attack risk, respectively, relative to no therapy. Based on trough C1‐INH(f) values for the 40 IU/kg (40.2%) and 60 IU/kg (48.0%) C1‐INH (SC) doses, the model predicted that 50% and 67% of the population, respectively, would see at least a 70% decrease in the risk of an attack. PMID:29316335

  15. Physical Fitness as It Pertains to Sustained Military Operations

    DTIC Science & Technology

    1986-05-01

    Vogel and his colleagues (Vogel et al., 1983, Murphy et al., 1985) measured initial V02 max, and 2-mile run time, anaerobic power of the arms and...trial, and troop performance was evaluated by observers. Vogel and his co-workers found arm strength and arm anaerobic p,4er to decrease following...defense from infantry ground attack. Measurements of isometric, handgrip strength and upper and lower body anaerobic power (using the Wingate test) were

  16. Changes in practice task constraints shape decision-making behaviours of team games players.

    PubMed

    Correia, Vanda; Araújo, Duarte; Duarte, Ricardo; Travassos, Bruno; Passos, Pedro; Davids, Keith

    2012-05-01

    This study examined the effects of manipulating relative positioning between defenders (initial distance apart) on emergent decision-making and actions in a 1 vs. 2 rugby union performance sub-phase. Twelve experienced youth players performed 80 trials of a 1 (attacker) vs. 2 (defenders) practice task in which the starting distance between defenders was systematically decreased. Movement displacement trajectories of participants were video recorded to obtain 2D positional data. The independent variable was the starting distance between defenders and dependent variables were: (i) performance outcome (try or tackle), (ii) mean speed of all players during performance, and (iii), time between the first crossover and the end of the trial. Repeated measures ANOVA was used to compare the effects of different starting distances on performance. Shorter starting distances between defenders were associated with a higher frequency of effective tackle outcomes, lower mean speeds of all participants, and a greater time period between the first crossover and the end of the trial. Decision-making behaviours emerged as a function of changes in participants' spatial location during performance. This observation supports the importance of manipulating key spatial-temporal variables in designing representative practice task constraints that induce functional player-environment interactions in team sports training. Copyright © 2011 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.

  17. Role of neonicotinyl insecticides in Washington apple integrated pest management. Part I. Control of lepidopteran pests

    PubMed Central

    Brunner, J. F.; Beers, E. H.; Dunley, J. E.; Doerr, M.; Granger, K.

    2005-01-01

    Three neonicotinyl insecticides, acetamiprid, thiacloprid and clothianidin, were evaluated for their impact on four species of lepidopteran pests of apple in Washington, the codling moth, Cydia pomonella (L.), the Pandemis leafroller, Pandemis pyrusana Kearfott, and the obliquebanded leafroller, Choristoneura rosaceana (Harris), and Lacanobia subjuncta (Grote & Robinson). None of the neonicotinyl insecticides demonstrated sufficient activity against P. pyrusana, C. rosaceana, or L. subjuncta to warrant field trials. Conversely, all had some activity against one or more stages of C. pomonella. Acetamiprid was highly toxic to larvae in laboratory bioassays, and had relatively long activity of field-aged residues (21 days). It also showed some toxicity to C. pomonella eggs (via topical exposure) and adults. Acetamiprid provided the highest level of fruit protection from C. pomonella attack in field trials conducted over five years in experimental orchards with extremely high codling moth pressure. Thiacloprid performed similarly in bioassays, but fruit protection in field trials was slightly lower than acetamiprid. Clothianidin showed moderate to high toxicity in bioassays, depending on the C. pomonella stage tested, but poor fruit protection from attack in field trials. None of the neonicotinyl insecticides were as toxic to larvae or effective in protecting fruit as the current standard organophosphate insecticide used for C. pomonella control, azinphosmethyl. However, both acetamiprid and thiacloprid should provide acceptable levels of C. pomonella control in commercial orchards where densities are much lower than in the experimental orchards used for our trials. The advantages and disadvantages of the neonicotinyl insecticides as replacements for the organophosphate insecticides and their role in a pest management system for Washington apple orchards are discussed. Abbreviation: MFR Maximum field rate PMID:16341246

  18. Pharmacologic Prevention of Incident Atrial Fibrillation: Long-Term Results From the ALLHAT (Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial).

    PubMed

    Dewland, Thomas A; Soliman, Elsayed Z; Yamal, Jose-Miguel; Davis, Barry R; Alonso, Alvaro; Albert, Christine M; Simpson, Lara M; Haywood, L Julian; Marcus, Gregory M

    2017-12-01

    Although atrial fibrillation (AF) guidelines indicate that pharmacological blockade of the renin-angiotensin system may be considered for primary AF prevention in hypertensive patients, previous studies have yielded conflicting results. We sought to determine whether randomization to lisinopril reduces incident AF or atrial flutter (AFL) compared with chlorthalidone in a large clinical trial cohort with extended post-trial surveillance. We performed a secondary analysis of the ALLHAT (Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial), a randomized, double-blind, active-controlled clinical trial that enrolled hypertensive individuals ≥55 years of age with at least one other cardiovascular risk factor. Participants were randomly assigned to receive amlodipine, lisinopril, or chlorthalidone. Individuals with elevated fasting low-density lipoprotein cholesterol levels were also randomized to pravastatin versus usual care. The primary outcome was the development of either AF or AFL as diagnosed by serial study ECGs or by Medicare claims data. Among 14 837 participants without prevalent AF or AFL, 2514 developed AF/AFL during a mean 7.5±3.2 years of follow-up. Compared with chlorthalidone, randomization to either lisinopril (hazard ratio, 1.04; 95% confidence interval, 0.94-1.15; P =0.46) or amlodipine (hazard ratio, 0.93; 95% confidence interval, 0.84-1.03; P =0.16) was not associated with a significant reduction in incident AF/AFL. Compared with chlorthalidone, treatment with lisinopril is not associated with a meaningful reduction in incident AF or AFL among older adults with a history of hypertension. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00000542. © 2017 American Heart Association, Inc.

  19. The calcium scare--what would Austin Bradford Hill have thought?

    PubMed

    Nordin, B E C; Lewis, J R; Daly, R M; Horowitz, J; Metcalfe, A; Lange, K; Prince, R L

    2011-12-01

    Detailed consideration of the suggested association between calcium supplementation and heart attacks has revealed weakness in the evidence which make the hypothesis highly implausible. The aim of this study was to evaluate the strength of the evidence that calcium supplementation increases the risk of myocardial infarction. This study used critical examination of a meta-analysis of the effects of calcium supplements on heart attacks in five prospective trials on 8,016 men and women, and consideration of related publications by the same author. The meta-analysis was found to be subject to several limitations including non-adherence to the clinical protocol, multiple endpoint testing and failure to correctly adjust for endpoint ascertainment. The main risk factors for myocardial infarction were not available for 65% of the participants, and none of the trials had cardiovascular disease as its primary endpoint. There were more overweight participants, more subjects on thyroxine and more men on calcium than on placebo. In particular, over 65% of all the heart attacks were self-reported. When the evidence was considered in the light of Austin Bradford Hill's six main criteria for disease causation, it was found not to be biologically plausible or strong or to reflect a dose-response relationship or to be consistent or to reflect the relationship between the trends in calcium supplementation and heart attacks in the community or to have been confirmed by experiment. The addition of a more recent trial on 1,460 women over 5 years reduced the relative risk to 1.23 (P = 0.0695). Present evidence that calcium supplementation increases heart attacks is too weak to justify a change in prescribing habits.

  20. Preliminary Findings of a Randomized Trial of Non-Pharmaceutical Interventions to Prevent Influenza Transmission in Households

    PubMed Central

    Cowling, Benjamin J.; Fung, Rita O. P.; Cheng, Calvin K. Y.; Fang, Vicky J.; Chan, Kwok Hung; Seto, Wing Hong; Yung, Raymond; Chiu, Billy; Lee, Paco; Uyeki, Timothy M.; Houck, Peter M.; Peiris, J. S. Malik; Leung, Gabriel M.

    2008-01-01

    Background There are sparse data on whether non-pharmaceutical interventions can reduce the spread of influenza. We implemented a study of the feasibility and efficacy of face masks and hand hygiene to reduce influenza transmission among Hong Kong household members. Methodology/Principal Findings We conducted a cluster randomized controlled trial of households (composed of at least 3 members) where an index subject presented with influenza-like-illness of <48 hours duration. After influenza was confirmed in an index case by the QuickVue Influenza A+B rapid test, the household of the index subject was randomized to 1) control or 2) surgical face masks or 3) hand hygiene. Households were visited within 36 hours, and 3, 6 and 9 days later. Nose and throat swabs were collected from index subjects and all household contacts at each home visit and tested by viral culture. The primary outcome measure was laboratory culture confirmed influenza in a household contact; the secondary outcome was clinically diagnosed influenza (by self-reported symptoms). We randomized 198 households and completed follow up home visits in 128; the index cases in 122 of those households had laboratory-confirmed influenza. There were 21 household contacts with laboratory confirmed influenza corresponding to a secondary attack ratio of 6%. Clinical secondary attack ratios varied from 5% to 18% depending on case definitions. The laboratory-based or clinical secondary attack ratios did not significantly differ across the intervention arms. Adherence to interventions was variable. Conclusions/Significance The secondary attack ratios were lower than anticipated, and lower than reported in other countries, perhaps due to differing patterns of susceptibility, lack of significant antigenic drift in circulating influenza virus strains recently, and/or issues related to the symptomatic recruitment design. Lessons learnt from this pilot have informed changes for the main study in 2008. Trial Registration ClinicalTrials.gov NCT00425893 HKClinicalTrials.com HKCTR-365 PMID:18461182

  1. Exposure-Response Model of Subcutaneous C1-Inhibitor Concentrate to Estimate the Risk of Attacks in Patients With Hereditary Angioedema.

    PubMed

    Zhang, Ying; Tortorici, Michael A; Pawaskar, Dipti; Pragst, Ingo; Machnig, Thomas; Hutmacher, Matthew; Zuraw, Bruce; Cicardi, Marco; Craig, Timothy; Longhurst, Hilary; Sidhu, Jagdev

    2018-03-01

    Subcutaneous C1-inhibitor (HAEGARDA, CSL Behring), is a US Food and Drug Administration (FDA)-approved, highly concentrated formulation of a plasma-derived C1-esterase inhibitor (C1-INH), which, in the phase III Clinical Studies for Optimal Management in Preventing Angioedema with Low-Volume Subcutaneous C1-inhibitor Replacement Therapy (COMPACT) trial, reduced the incidence of hereditary angioedema (HAE) attacks when given prophylactically. Data from the COMPACT trial were used to develop a repeated time-to-event model to characterize the timing and frequency of HAE attacks as a function of C1-INH activity, and then develop an exposure-response model to assess the relationship between C1-INH functional activity levels (C1-INH(f)) and the risk of an attack. The C1-INH(f) values of 33.1%, 40.3%, and 63.1% were predicted to correspond with 50%, 70%, and 90% reductions in the HAE attack risk, respectively, relative to no therapy. Based on trough C1-INH(f) values for the 40 IU/kg (40.2%) and 60 IU/kg (48.0%) C1-INH (SC) doses, the model predicted that 50% and 67% of the population, respectively, would see at least a 70% decrease in the risk of an attack. © 2018 The Authors CPT: Pharmacometrics & Systems Pharmacology published by Wiley Periodicals, Inc. on behalf of American Society for Clinical Pharmacology and Therapeutics.

  2. Genetic and phenotypic resistance in lodgepole pine to attack by mountain pine beetle

    Treesearch

    Alvin Yanchuk; Kimberly Wallin

    2007-01-01

    The recent outbreak of mountain pine beetle (MPB) (Dendroctonus ponderosae) in British Columbia provided an opportunity to examine genetic variation of differential attack and resistance in a 20-year old lodgepole pine open-pollinated (OP) family trial. Approximately 2,500 individuals from 180 OP parent-tree collections (~14 trees per parent), from...

  3. Treating and Preventing Influenza in Aged Care Facilities: A Cluster Randomised Controlled Trial

    PubMed Central

    Booy, Robert; Lindley, Richard I.; Dwyer, Dominic E.; Yin, Jiehui K.; Heron, Leon G.; Moffatt, Cameron R. M.; Chiu, Clayton K.; Rosewell, Alexander E.; Dean, Anna S.; Dobbins, Timothy; Philp, David J.; Gao, Zhanhai; MacIntyre, C. Raina

    2012-01-01

    Background Influenza is an important cause of morbidity and mortality for frail older people. Whilst the antiviral drug oseltamivir (a neuraminidase inhibitor) is approved for treatment and prophylaxis of influenza during outbreaks, there have been no trials comparing treatment only (T) versus treatment and prophylaxis (T&P) in Aged Care Facilities (ACFs). Our objective was to compare a policy of T versus T&P for influenza outbreaks in ACFs. Methods and Findings We performed a cluster randomised controlled trial in 16 ACFs, that followed a policy of either “T”—oseltamivir treatment (75 mg twice a day for 5 days)—or “T&P”—treatment and prophylaxis (75 mg once a day for 10 days) for influenza outbreaks over three years, in addition to enhanced surveillance. The primary outcome measure was the attack rate of influenza. Secondary outcomes measures were deaths, hospitalisation, pneumonia and adverse events. Laboratory testing was performed to identify the viral cause of influenza-like illness (ILI) outbreaks. The study period 30 June 2006 to 23 December 2008 included three southern hemisphere winters. During that time, influenza was confirmed as the cause of nine of the 23 ILI outbreaks that occurred amongst the 16 ACFs. The policy of T&P resulted in a significant reduction in the influenza attack rate amongst residents: 93/255 (36%) in residents in T facilities versus 91/397 (23%) in T&P facilities (p = 0.002). We observed a non-significant reduction in staff: 46/216 (21%) in T facilities versus 47/350 (13%) in T&P facilities (p = 0.5). There was a significant reduction in mean duration of outbreaks (T = 24 days, T&P = 11 days, p = 0.04). Deaths, hospitalisations and pneumonia were non-significantly reduced in the T&P allocated facilities. Drug adverse events were common but tolerated. Conclusion Our trial lacked power but these results provide some support for a policy of “treatment and prophylaxis” with oseltamivir in controlling influenza outbreaks in ACFs. Trail Registration Australian Clinical Trials Registry ACTRN12606000278538 PMID:23082123

  4. Effects of tonabersat on migraine with aura: a randomised, double-blind, placebo-controlled crossover study.

    PubMed

    Hauge, Anne W; Asghar, Mohammed S; Schytz, Henrik W; Christensen, Karl; Olesen, Jes

    2009-08-01

    Migraine with aura is thought likely to be caused by cortical spreading depression (CSD). Tonabersat inhibits CSD, and we therefore investigated whether tonabersat has a preventive effect in migraine with aura. In this randomised, double-blind, placebo-controlled crossover trial, 40 mg tonabersat once daily was compared with matched placebo in patients who had at least one aura attack per month during the past 3 months. Randomisation was by computer-generated list. Patients kept a detailed diary to enable objective diagnosis of each attack as migraine with aura, migraine without aura, or other type of headache. Primary endpoints were a reduction in aura attacks with or without headache and a reduction in migraine headache days with or without an aura. Analysis was per protocol. This trial is registered, number NCT00332007. 39 patients were included in the study, of whom 31 were included in the statistical analysis of efficacy. Median (IQR) attacks of aura were reduced from 3.2 (1.0-5.0) per 12 weeks on placebo to 1.0 (0-3.0) on tonabersat (p=0.01), whereas the other primary outcome measure, median migraine headache days with or without aura, was not significantly different between placebo and tonabersat groups (3.0 days in each group; p=0.09). Tonabersat was well tolerated but overall had more side-effects than placebo. Tonabersat showed a preventive effect on attacks of migraine aura but no efficacy on non-aura attacks, in keeping with its known inhibitory effect on CSD. The results support the theory that auras are caused by CSD and that this phenomenon is not involved in attacks without aura. Minster Pharmaceuticals; Lundbeck Foundation.

  5. Breakthrough attacks in patients with hereditary angioedema receiving long-term prophylaxis are responsive to icatibant: findings from the Icatibant Outcome Survey.

    PubMed

    Aberer, Werner; Maurer, Marcus; Bouillet, Laurence; Zanichelli, Andrea; Caballero, Teresa; Longhurst, Hilary J; Perrin, Amandine; Andresen, Irmgard

    2017-01-01

    Patients with hereditary angioedema (HAE) due to C1-inhibitor deficiency (C1-INH-HAE) experience recurrent attacks of cutaneous or submucosal edema that may be frequent and severe; prophylactic treatments can be prescribed to prevent attacks. However, despite the use of long-term prophylaxis (LTP), breakthrough attacks are known to occur. We used data from the Icatibant Outcome Survey (IOS) to evaluate the characteristics of breakthrough attacks and the effectiveness of icatibant as a treatment option. Data on LTP use, attacks, and treatments were recorded. Attack characteristics, treatment characteristics, and outcomes (time to treatment, time to resolution, and duration of attack) were compared for attacks that occurred with versus without LTP. Data on 3228 icatibant-treated attacks from 448 patients with C1-INH-HAE were analyzed; 30.1% of attacks occurred while patients were using LTP. Attack rate, attack severity, and the distribution of attack sites were similar across all types of LTP used, and were comparable to the results found in patients who did not receive LTP. Attacks were successfully treated with icatibant; 82.5% of all breakthrough attacks were treated with a single icatibant injection without C1-INH rescue medication. Treatment outcomes were comparable for breakthrough attacks across all LTP types, and for attacks without LTP. Patients who use LTP should be aware that breakthrough attacks can occur, and such attacks can be severe. Thus, patients with C1-INH-HAE using LTP should have emergency treatment readily available. Data from IOS show that icatibant is effective for the treatment of breakthrough attacks. Trial Registration NCT01034969.

  6. Official 1996 Mock Trial Materials for the Twenty-Fourth Annual District of Columbia Public Schools Mock Trial Program. Kyle Wilkins, Plaintiff, v. New Columbia County School District, Defendant.

    ERIC Educational Resources Information Center

    Ashbrook, Alexandra M.

    This guide contains the 1996 mock trial materials for the District of Columbia mock trial program. The trial focuses on a high school student who died of a heart attack attributed to the use of steroids. The plaintiff, the student's father, alleges that the school, its principal, and track coach were negligent in the death because they failed to…

  7. The effects of folic acid and pyridoxine supplementation on characteristics of migraine attacks in migraine patients with aura: A double-blind, randomized placebo-controlled, clinical trial.

    PubMed

    Askari, Gholamreza; Nasiri, Morteza; Mozaffari-Khosravi, Hassan; Rezaie, Masod; Bagheri-Bidakhavidi, Mahdieh; Sadeghi, Omid

    2017-06-01

    The aim of this study was to assess the effects of folic acid alone and in combination with pyridoxine on characteristics of migraine attacks in adult migraine patients with aura. This double-blind, randomized placebo-controlled, clinical trial was conducted on 95 migraine patients with aura (age range 18-65 y) in Isfahan, Islamic Republic of Iran, in 2014. Patients were randomly allocated to receive folic acid (5 mg/d) plus pyridoxine (80 mg/d) or folic acid alone (5 mg/d) or placebo (lactose) for 3 mo. Characteristics of migraine attacks including headache severity, attacks frequency, duration, and headache diary results (HDRs) were obtained for each patient at baseline and at the end of the study. Folic acid plus pyridoxine intake resulted in a significant decrease compared with placebo in headache severity (-2.71 ± 0.08 versus -2.19 ± 0.05; P < 0.001), attack frequency (-3.35 ± 0.09 versus -2.73 ± 0.05; P < 0.001), duration (-7.25 ± 0.17 versus -6.5 ± 0.07; P < 0.001), and HDR (-74.15 ± 0.2 versus -72.73 ± 0.1; P < 0.001). Additionally, the reduction in these characteristics of migraine attacks in the folic acid plus pyridoxine group was significant compared with the group given folic acid alone (P < 0.001). However, these beneficial effects of the combined supplement became nonsignificant for attack duration compared with the folic acid-only and placebo groups after controlling for confounders. Folic acid intake without pyridoxine did not lead to a significant decrease in characteristics of migraine attacks compared with placebo group. Supplementation of folic acid with pyridoxine could decrease the characteristics of migraine attacks including headache severity, attack frequency, and HDR; however, further studies are needed to shed light on the findings of the present study. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Traditional Chinese patent medicine for prophylactic treatment of migraine: a meta-analysis of randomized, double-blind, placebo-controlled trials.

    PubMed

    Xiao, Y; Yuan, L; Liu, Y; Sun, X; Cheng, J; Wang, T; Li, F; Luo, R; Zhao, X

    2015-02-01

    A large number of traditional Chinese patent medicines (TCPMs) are widely used to treat migraine in China. However, it is uncertain whether there is robust evidence on the effects of TCPMs for migraine. A meta-analysis of randomized, double-blind, placebo-controlled trials was performed to evaluate the efficacy and safety of TCPMs in patients with migraine. Comprehensive searches were conducted on the Medline database, Cochrane Library, the China National Knowledge Infrastructure database, the Chinese Biomedical Literature database and the Wanfang database up to December 2013. Summary estimates, including 95% confidence intervals (CIs), were calculated for frequency of migraine attacks, response rate and headache intensity. A total of seven trials including 582 participants with migraine met the selection criteria. TCPM was significantly more likely to reduce the frequency of migraine attacks compared with placebo (standardized mean difference -0.54; 95% CI -0.72, -0.36; P < 0.001). TCPM was associated with an improvement of response rate compared with placebo (summary relative risk 4.63, 95% CI 2.74, 7.80, P < 0.001; therapeutic gain 24.1%; number needed to treat 4.1). Headache intensity was attenuated by TCPM compared with placebo (standardized mean difference -1.33; 95% CI -1.79, -0.87; P < 0.001). The adverse events of TCPM were no different from those of placebo. TCPMs are effective and well tolerated in the prophylactic treatment of migraine. © 2014 EAN.

  9. Nonvitamin-K-antagonist oral anticoagulants versus warfarin in patients with atrial fibrillation and previous stroke or transient ischemic attack: An updated systematic review and meta-analysis of randomized controlled trials.

    PubMed

    Ntaios, George; Papavasileiou, Vasileios; Diener, Hans-Chris; Makaritsis, Konstantinos; Michel, Patrik

    2017-08-01

    Background In a previous systematic review and meta-analysis, we assessed the efficacy and safety of nonvitamin-K antagonist oral anticoagulants versus warfarin in patients with atrial fibrillation and stroke or transient ischemic attack. Since then, new information became available. Aim The aim of the present work was to update the results of the previous systematic review and meta-analysis. Methods We searched PubMed until 24 August 2016 for randomized controlled trials using the following search items: "atrial fibrillation" and "anticoagulation" and "warfarin" and "previous stroke or transient ischemic attack." Eligible studies had to be phase III trials in patients with atrial fibrillation comparing warfarin with nonvitamin-K antagonist oral anticoagulants currently on the market or with the intention to be brought to the market in North America or Europe. The outcomes assessed in the efficacy analysis included stroke or systemic embolism, stroke, ischemic or unknown stroke, disabling or fatal stroke, hemorrhagic stroke, cardiovascular death, death from any cause, and myocardial infarction. The outcomes assessed in the safety analysis included major bleeding, intracranial bleeding, and major gastrointestinal bleeding. We performed fixed effects analyses on intention-to-treat basis. Results Among 183 potentially eligible articles, four were included in the meta-analysis. In 20,500 patients, compared to warfarin, nonvitamin-K antagonist oral anticoagulants were associated with a significant reduction of stroke/systemic embolism (relative risk reduction: 13.7%, absolute risk reduction: 0.78%, number needed to treat to prevent one event: 127), hemorrhagic stroke (relative risk reduction: 50.0%, absolute risk reduction: 0.63%, number needed to treat: 157), any stroke (relative risk reduction: 13.1%, absolute risk reduction: 0.7%, number needed to treat: 142), and intracranial hemorrhage (relative risk reduction: 46.1%, absolute risk reduction: 0.88%, number needed to treat: 113) over 1.8-2.8 years. Conclusions This updated meta-analysis in 20,500 atrial fibrillation patients with previous stroke or transient ischemic attack shows that compared to warfarin non-vitamin-K antagonist oral anticoagulants are associated with a significant reduction of stroke, stroke or systemic embolism, hemorrhagic stroke, and intracranial bleeding.

  10. Performance Improvement of Power Analysis Attacks on AES with Encryption-Related Signals

    NASA Astrophysics Data System (ADS)

    Lee, You-Seok; Lee, Young-Jun; Han, Dong-Guk; Kim, Ho-Won; Kim, Hyoung-Nam

    A power analysis attack is a well-known side-channel attack but the efficiency of the attack is frequently degraded by the existence of power components, irrelative to the encryption included in signals used for the attack. To enhance the performance of the power analysis attack, we propose a preprocessing method based on extracting encryption-related parts from the measured power signals. Experimental results show that the attacks with the preprocessed signals detect correct keys with much fewer signals, compared to the conventional power analysis attacks.

  11. Management of acute attacks of hereditary angioedema: potential role of icatibant.

    PubMed

    Longhurst, Hilary J

    2010-09-07

    Icatibant (Firazyr(®)) is a novel subcutaneous treatment recently licensed in the European Union for acute hereditary angioedema. Hereditary angioedema, resulting from inherited partial C1 inhibitor deficiency, is a disabling condition characterized by intermittent episodes of bradykinin-mediated angioedema. Icatibant blocks bradykinin B2 receptors, attenutating the episode. Randomized double-blind, placebo-controlled trials of icatibant, showed significant superiority over oral tranexamic acid in 74 European patients and a trend to improvement in a similar US trial comparing icatibant with placebo in 55 patients. Outcomes for several endpoints did not reach significance in the US trial, perhaps because of low participant numbers and confounding factors: a further trial is planned. Open label studies have shown benefit in multiple treatments for attacks at all sites. Approximately 10% of patients require a second dose for re-emergent symptoms, usually 10 to 27 hours after the initial treatment. Its subcutaneous route of administration, good tolerability and novel mode of action make icatibant a promising addition to the limited repertoire of treatments for hereditary angioedema.

  12. Numerical simulation of the optimal two-mode attacks for two-way continuous-variable quantum cryptography in reverse reconciliation

    NASA Astrophysics Data System (ADS)

    Zhang, Yichen; Li, Zhengyu; Zhao, Yijia; Yu, Song; Guo, Hong

    2017-02-01

    We analyze the security of the two-way continuous-variable quantum key distribution protocol in reverse reconciliation against general two-mode attacks, which represent all accessible attacks at fixed channel parameters. Rather than against one specific attack model, the expression of secret key rates of the two-way protocol are derived against all accessible attack models. It is found that there is an optimal two-mode attack to minimize the performance of the protocol in terms of both secret key rates and maximal transmission distances. We identify the optimal two-mode attack, give the specific attack model of the optimal two-mode attack and show the performance of the two-way protocol against the optimal two-mode attack. Even under the optimal two-mode attack, the performances of two-way protocol are still better than the corresponding one-way protocol, which shows the advantage of making double use of the quantum channel and the potential of long-distance secure communication using a two-way protocol.

  13. Development and Validation of a Model to Predict Absolute Vascular Risk Reduction by Moderate-Intensity Statin Therapy in Individual Patients With Type 2 Diabetes Mellitus: The Anglo Scandinavian Cardiac Outcomes Trial, Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial, and Collaborative Atorvastatin Diabetes Study.

    PubMed

    Kaasenbrood, Lotte; Poulter, Neil R; Sever, Peter S; Colhoun, Helen M; Livingstone, Shona J; Boekholdt, S Matthijs; Pressel, Sara L; Davis, Barry R; van der Graaf, Yolanda; Visseren, Frank L J

    2016-05-01

    In this study, we aimed to translate the average relative effect of statin therapy from trial data to the individual patient with type 2 diabetes mellitus by developing and validating a model to predict individualized absolute risk reductions (ARR) of cardiovascular events. Data of 2725 patients with type 2 diabetes mellitus from the Lipid Lowering Arm of the Anglo Scandinavian Cardiac Outcomes Trial (ASCOT-LLA) study (atorvastatin 10 mg versus placebo) were used for model derivation. The model was based on 8 clinical predictors including treatment allocation (statin/placebo). Ten-year individualized ARR on major cardiovascular events by statin therapy were calculated for each patient by subtracting the estimated on-treatment risk from the estimated off-treatment risk. Predicted 10-year ARR by statin therapy was <2% for 13% of the patients. About 30% had an ARR of >4% (median ARR, 3.2%; interquartile range, 2.5%-4.3%; 95% confidence interval for 3.2% ARR, -1.4% to 6.8%). Addition of treatment interactions did not improve model performance. Therefore, the wide distribution in ARR was a consequence of the underlying distribution in cardiovascular risk enrolled in these trials. External validation of the model was performed in data from the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT-LLT; pravastatin 40 mg versus usual care) and Collaborative Atorvastatin Diabetes Study (CARDS; atorvastatin 10 mg versus placebo) of 3878 and 2838 patients with type 2 diabetes mellitus, respectively. Model calibration was adequate in both external data sets, discrimination was moderate (ALLHAT-LLT: c-statistics, 0.64 [95% confidence interval, 0.61-0.67] and CARDS: 0.68 [95% confidence interval, 0.64-0.72]). ARRs of major cardiovascular events by statin therapy can be accurately estimated for individual patients with type 2 diabetes mellitus using a model based on routinely available patient characteristics. There is a wide distribution in ARR that may complement informed decision making. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00327418 (CARDS) and NCT00000542 (ALLHAT). © 2016 American Heart Association, Inc.

  14. Conestat alfa for the treatment of angioedema attacks

    PubMed Central

    Davis, Benjamin; Bernstein, Jonathan A

    2011-01-01

    Recently, multiple C1 inhibitor (C1-INH) replacement products have been approved for the treatment of hereditary angioedema (HAE). This review summarizes HAE and its current treatment modalities and focuses on findings from bench to bedside trials of a new C1-INH replacement, conestat alfa. Conestat alfa is unique among the other C1-INH replacement products because it is produced from transgenic rabbits rather than derived from human plasma donors, which can potentially allow an unlimited source of drug without any concern of infectious transmission. The clinical trial data generated to date indicate that conestat alfa is safe and effective for the treatment of acute HAE attacks. PMID:21753889

  15. Effect of ticagrelor with clopidogrel on high on-treatment platelet reactivity in acute stroke or transient ischemic attack (PRINCE) trial: Rationale and design.

    PubMed

    Wang, Yilong; Lin, Yi; Meng, Xia; Chen, Weiqi; Chen, Guohua; Wang, Zhimin; Wu, Jialing; Wang, Dali; Li, Jianhua; Cao, Yibin; Xu, Yuming; Zhang, Guohua; Li, Xiaobo; Pan, Yuesong; Li, Hao; Liu, Liping; Zhao, Xingquan; Wang, Yongjun

    2017-04-01

    Rationale and aim Little is known about the safety and efficacy of the combination of ticagrelor and aspirin in acute ischemic stroke. This study aimed to evaluate whether the combination of ticagrelor and aspirin was superior to that of clopidogrel and aspirin in reducing the 90-day high on-treatment platelet reactivity for acute minor stroke or transient ischemic attack, especially for carriers of cytochrome P450 2C19 loss-of-function allele. Sample size and design This study was designed as a prospective, multicenter, randomized, open-label, active-controlled, and blind-endpoint, phase II b trial. The required sample size was 952 patients. It was registered with ClinicalTrials.gov (NCT02506140). Study outcomes The primary outcome was the proportion of patients with high on-treatment platelet reactivity at 90 days. High on-treatment platelet reactivity is defined as the P2Y12 reaction unit >208 measured using the VerifyNow P2Y12 assay. Conclusion The Platelet Reactivity in Acute Non-disabling Cerebrovascular Events study explored whether ticagrelor combined with aspirin could reduce further the proportion of patients with high on-treatment platelet reactivity at 90 days after acute minor stroke or transient ischemic attack compared with clopidogrel and aspirin.

  16. Efficacy of a Community-Based Physical Activity Program KM2H2 for Stroke and Heart Attack Prevention among Senior Hypertensive Patients: A Cluster Randomized Controlled Phase-II Trial

    PubMed Central

    Gong, Jie; Chen, Xinguang; Li, Sijian

    2015-01-01

    Objective To evaluate the efficacy of the program Keep Moving toward Healthy Heart and Healthy Brain (KM2H2) in encouraging physical activities for the prevention of heart attack and stroke among hypertensive patients enrolled in the Community-Based Hypertension Control Program (CBHCP). Design Cluster randomized controlled trial with three waves of longitudinal assessments at baseline, 3 and 6 months post intervention. Setting Community-based and patient-centered self-care for behavioral intervention in urban settings of China. Participants A total of 450 participants diagnosed with hypertension from 12 community health centers in Wuhan, China were recruited, and were randomly assigned by center to receive either KM2H2 plus standard CBHCP care (6 centers and 232 patients) or the standard care only (6 centers and 218 patients). Intervention KM2H2 is a behavioral intervention guided by the Transtheoretical Model, the Model of Personalized Medicine and Social Capital Theory. It consists of six intervention sessions and two booster sessions engineered in a progressive manner. The purpose is to motivate and maintain physical activities for the prevention of heart attack and stroke. Outcome Measures Heart attack and stroke (clinically diagnosed, primary outcome), blood pressure (measured, secondary outcome), and physical activity (self-report, tertiary outcome) were assessed at the individual level during the baseline, 3- and 6-month post-intervention. Results Relative to the standard care, receiving KM2H2 was associated with significant reductions in the incidence of heart attack (3.60% vs. 7.03%, p < .05) and stroke (5.11% vs. 9.90%, p<0.05), and moderate reduction in blood pressure (-3.72mmHg in DBP and -2.92 mmHg in DBP) at 6-month post-intervention; and significant increases in physical activity at 3- (d = 0.53, 95% CI: 0.21, 0.85) and 6-month (d = 0.45, 95% CI: 0.04, 0.85) post-intervention, respectively. Conclusion The program KM2H2 is efficacious to reduce the risk of heart attack and stroke among senior patients who are on anti-hypertensive medication. Findings of this study provide solid data supporting a formal phase-III trial to establish the effectiveness of KM2H2 for use in community settings for prevention. Trial Registration ISRCTN Register ISRCTN12608966 PMID:26426421

  17. Thrombus Aspiration in ST-Segment-Elevation Myocardial Infarction: An Individual Patient Meta-Analysis: Thrombectomy Trialists Collaboration.

    PubMed

    Jolly, Sanjit S; James, Stefan; Džavík, Vladimír; Cairns, John A; Mahmoud, Karim D; Zijlstra, Felix; Yusuf, Salim; Olivecrona, Goran K; Renlund, Henrik; Gao, Peggy; Lagerqvist, Bo; Alazzoni, Ashraf; Kedev, Sasko; Stankovic, Goran; Meeks, Brandi; Frøbert, Ole

    2017-01-10

    Thrombus aspiration during percutaneous coronary intervention (PCI) for the treatment of ST-segment-elevation myocardial infarction (STEMI) has been widely used; however, recent trials have questioned its value and safety. In this meta-analysis, we, the trial investigators, aimed to pool the individual patient data from these trials to determine the benefits and risks of thrombus aspiration during PCI in patients with ST-segment-elevation myocardial infarction. Included were large (n≥1000), randomized, controlled trials comparing manual thrombectomy and PCI alone in patients with ST-segment-elevation myocardial infarction. Individual patient data were provided by the leadership of each trial. The prespecified primary efficacy outcome was cardiovascular mortality within 30 days, and the primary safety outcome was stroke or transient ischemic attack within 30 days. The 3 eligible randomized trials (TAPAS [Thrombus Aspiration During Percutaneous Coronary Intervention in Acute Myocardial Infarction], TASTE [Thrombus Aspiration in ST-Elevation Myocardial Infarction in Scandinavia], and TOTAL [Trial of Routine Aspiration Thrombectomy With PCI Versus PCI Alone in Patients With STEMI]) enrolled 19 047 patients, of whom 18 306 underwent PCI and were included in the primary analysis. Cardiovascular death at 30 days occurred in 221 of 9155 patients (2.4%) randomized to thrombus aspiration and 262 of 9151 (2.9%) randomized to PCI alone (hazard ratio, 0.84; 95% confidence interval, 0.70-1.01; P=0.06). Stroke or transient ischemic attack occurred in 66 (0.8%) randomized to thrombus aspiration and 46 (0.5%) randomized to PCI alone (odds ratio, 1.43; 95% confidence interval, 0.98-2.10; P=0.06). There were no significant differences in recurrent myocardial infarction, stent thrombosis, heart failure, or target vessel revascularization. In the subgroup with high thrombus burden (TIMI [Thrombolysis in Myocardial Infarction] thrombus grade ≥3), thrombus aspiration was associated with fewer cardiovascular deaths (170 [2.5%] versus 205 [3.1%]; hazard ratio, 0.80; 95% confidence interval, 0.65-0.98; P=0.03) and with more strokes or transient ischemic attacks (55 [0.9%] versus 34 [0.5%]; odds ratio, 1.56; 95% confidence interval, 1.02-2.42, P=0.04). However, the interaction P values were 0.32 and 0.34, respectively. Routine thrombus aspiration during PCI for ST-segment-elevation myocardial infarction did not improve clinical outcomes. In the high thrombus burden group, the trends toward reduced cardiovascular death and increased stroke or transient ischemic attack provide a rationale for future trials of improved thrombus aspiration technologies in this high-risk subgroup. URLs: http://www.ClinicalTrials.gov http://www.crd.york.ac.uk/prospero/. Unique identifiers: NCT02552407 and CRD42015025936. © 2016 American Heart Association, Inc.

  18. B vitamins in patients with recent transient ischaemic attack or stroke in the VITAmins TO Prevent Stroke (VITATOPS) trial: a randomised, double-blind, parallel, placebo-controlled trial.

    PubMed

    2010-09-01

    Epidemiological studies suggest that raised plasma concentrations of total homocysteine might be a risk factor for major vascular events. Whether lowering total homocysteine with B vitamins prevents major vascular events in patients with previous stroke or transient ischaemic attack is unknown. We aimed to assess whether the addition of once-daily supplements of B vitamins to usual medical care would lower total homocysteine and reduce the combined incidence of non-fatal stroke, non-fatal myocardial infarction, and death attributable to vascular causes in patients with recent stroke or transient ischaemic attack of the brain or eye. In this randomised, double-blind, parallel, placebo-controlled trial, we assigned patients with recent stroke or transient ischaemic attack (within the past 7 months) from 123 medical centres in 20 countries to receive one tablet daily of placebo or B vitamins (2 mg folic acid, 25 mg vitamin B6, and 0.5 mg vitamin B12). Patients were randomly allocated by means of a central 24-h telephone service or an interactive website, and allocation was by use of random permuted blocks stratified by hospital. Participants, clinicians, carers, and investigators who assessed outcomes were masked to the assigned intervention. The primary endpoint was the composite of stroke, myocardial infarction, or vascular death. All patients randomly allocated to a group were included in the analysis of the primary endpoint. This trial is registered with ClinicalTrials.gov, NCT00097669, and Current Controlled Trials, ISRCTN74743444. Between Nov 19, 1998, and Dec 31, 2008, 8164 patients were randomly assigned to receive B vitamins (n=4089) or placebo (n=4075). Patients were followed up for a median duration of 3.4 years (IQR 2.0-5.5). 616 (15%) patients assigned to B vitamins and 678 (17%) assigned to placebo reached the primary endpoint (risk ratio [RR] 0.91, 95% CI 0.82 to 1.00, p=0.05; absolute risk reduction 1.56%, -0.01 to 3.16). There were no unexpected serious adverse reactions and no significant differences in common adverse effects between the treatment groups. Daily administration of folic acid, vitamin B6, and vitamin B12 to patients with recent stroke or transient ischaemic attack was safe but did not seem to be more effective than placebo in reducing the incidence of major vascular events. These results do not support the use of B vitamins to prevent recurrent stroke. The results of ongoing trials and an individual patient data meta-analysis will add statistical power and precision to present estimates of the effect of B vitamins. Australia National Health and Medical Research Council, UK Medical Research Council, Singapore Biomedical Research Council, Singapore National Medical Research Council, Australia National Heart Foundation, Royal Perth Hospital Medical Research Foundation, and Health Department of Western Australia. Copyright 2010 Elsevier Ltd. All rights reserved.

  19. Coronary heart disease risk in patients with stroke or transient ischemic attack and no known coronary heart disease: findings from the Stroke Prevention by Aggressive Reduction in Cholesterol Levels (SPARCL) trial.

    PubMed

    Amarenco, Pierre; Goldstein, Larry B; Sillesen, Henrik; Benavente, Oscar; Zweifler, Richard M; Callahan, Alfred; Hennerici, Michael G; Zivin, Justin A; Welch, K Michael A

    2010-03-01

    Noncoronary forms of atherosclerosis (including transient ischemic attacks or stroke of carotid origin or >50% stenosis of the carotid artery) are associated with a 10-year vascular risk of >20% and are considered as a coronary heart disease (CHD) -risk equivalent from the standpoint of lipid management. The Stroke Prevention by Aggressive Reduction in Cholesterol Levels (SPARCL) trial included patients with stroke or transient ischemic attack and no known CHD regardless of the presence of carotid atherosclerosis. We evaluated the risk of developing clinically recognized CHD in SPARCL patients. A total of 4731 patients (mean age, 63 years) was randomized to 80 mg/day atorvastatin placebo. The rates of major coronary event, any CHD event, and any revascularization procedure were evaluated. After 4.9 years of follow-up, the risks of a major coronary event and of any CHD end point in the placebo group were 5.1% and 8.6%, respectively. The rate of outcome of stroke decreased over time, whereas the major coronary event rate was stable. Relative to those having a large vessel-related stroke at baseline, those having a transient ischemic attack, hemorrhagic stroke, small vessel stroke, or a stroke of unknown cause had similar absolute rates for a first major coronary event and for any CHD event; transient ischemic attack, small vessel, and unknown cause groups had lower absolute revascularization procedure rates. Major coronary event, any CHD event, and any revascularization procedure rates were similarly reduced in all baseline stroke subtypes in the atorvastatin arm compared with placebo with no heterogeneity between groups. CHD risk can be substantially reduced by atorvastatin therapy in patients with recent stroke or transient ischemic attack regardless of stroke subtype.

  20. Five-year operational trial of verbenone to deter mountain pine beetle (Dendroctonus ponderosae); Coleoptera: Scolytidae) attack of lodgepole pine (Pinus contorta).

    Treesearch

    R.A. Progar

    2005-01-01

    The antiaggregation pheromone verbenone was operationally tested for 5 yr to deter mass attack by the mountain pine beetle on lodgepole pine in campgrounds and administrative areas surrounding Redfish and Little Redfish Lakes at the Sawtooth National Recreation Area in central Idaho. Each year, five-gram verbenone pouches were evenly distributed (-10 m apart) within...

  1. Histamine Antagonists for Treatment of Peripheral Vertigo: A Meta-Analysis.

    PubMed

    Amini, Afshin; Heidari, Kamran; Kariman, Hamid; Taghizadeh, Mehrdad; Hatamabadi, Hamidreza; Shahrami, Ali; Derakhshanfar, Hojat; Asadollahi, Shadi

    2015-08-01

    Vertigo, the hallucination of movement of oneself or one's surroundings, can have substantial adverse effects on the quality of life of affected patients. It is essential to decrease the frequency, severity, and duration of vertigo attacks using effective medications with minimal debilitating adverse effects. We performed a meta-analysis of available clinical trials to evaluate the efficacy of histamine antagonists in the treatment of vertigo compared to the rate of resolution in untreated control groups. A systematic search of articles in any language from January 1970 to March 2015 was performed through the following databases: the Cochrane Central Register of Controlled Trials, Medical Literature Analysis and Retrieval System Online, the Excerpta Medica Database, Cumulative Index to Nursing and Allied Health Literature, Latin American and Caribbean Health Sciences Literature, Allied and Complementary Medicine Database, Web of Science, ClinicalTrials.gov, and Google. Randomized controlled trials comparing each kind of antihistamine to untreated control participants in the treatment of vertigo (blinded/unblinded) were screened for inclusion. Three reviewers separately performed data extraction from the included trials using a standard data abstraction form. Three other researchers read the final list of all articles retained. Discrepancies were settled by mutual consensus between the authors. Random effects models were applied to estimate the pooled odds ratio (OR) and 95% confidence interval (CI) using the Review Manager software. The evaluation of publication bias was performed by Egger's test and Begg's funnel plot. We identified 13 eligible citations. The pooled OR was 5.370, 95% CI (3.263-8.839), and I2=56.0%, with no obvious evidence of publication bias. Our results provide clarification of the effectiveness of several categories of histamine antagonists compared with placebos in controlling peripheral vertigo.

  2. Employment Standards for Australian Urban Firefighters: Part 4: Physical Aptitude Tests and Standards.

    PubMed

    Fullagar, Hugh H K; Sampson, John A; Mott, Brendan J; Burdon, Catriona A; Taylor, Nigel A S; Groeller, Herbert

    2015-10-01

    Firefighter physical aptitude tests were administered to unskilled subjects and operational firefighters to evaluate the impact that testing bias associated with gender, age, activity-specific skills, or task familiarity may have upon establishing performance thresholds. These tests were administered in sequence, simulating hazmat incidents, ventilation fan carriage (stairs), motor-vehicle rescues, bushfire incidents, fire attacks, and a firefighter rescue. Participants included two unskilled samples (N = 14 and 22) and 143 firefighters. Firefighter performance was not significantly different from the unskilled subjects. Participants from both genders passed the test, with scores unrelated to performance skill or age; however, familiarization significantly improved performance when the test was repeated. These outcomes confirmed this test to be gender-, age-, and skill-neutral. Familiarization effects could be removed through performing a single, pre-selection trial of the test battery.

  3. Antiplatelet Agents for the Secondary Prevention of Ischemic Stroke or Transient Ischemic Attack: A Network Meta-Analysis.

    PubMed

    Wang, Wen; Zhang, Lu; Liu, Weiming; Zhu, Qin; Lan, Qing; Zhao, Jizong

    2016-05-01

    Stroke can cause high morbidity and mortality, and ischemic stroke (IS) and transient ischemic attack (TIA) patients have a high stroke recurrence rate. Antiplatelet agents are the standard therapy for these patients, but it is often difficult for clinicians to select the best therapy from among the multiple treatment options. We therefore performed a network meta-analysis to estimate the efficacy of antiplatelet agents for secondary prevention of recurrent stroke. We systematically searched 3 databases (PubMed, Embase, and Cochrane) for relevant studies published through August 2015. The primary end points of this meta-analysis were overall stroke, hemorrhagic stroke, and fatal stroke. A total of 30 trials were included in our network meta-analysis and abstracted data. Among the therapies evaluated in the included trials, the estimates for overall stroke and hemorrhagic stroke for cilostazol (Cilo) were significantly better than those for aspirin (odds ratio [OR] = .64, 95% credibility interval [CrI], .45-.91; OR = .23, 95% CrI, .08-.58). The estimate for fatal stroke was highest for Cilo plus aspirin combination therapy, followed by Cilo therapy. The results of our meta-analysis indicate that Cilo significantly improves overall stroke and hemorrhagic stroke in IS or TIA patients and reduces fatal stroke, but with low statistical significance. Our results also show that Cilo was significantly more efficient than other therapies in Asian patients; therefore, future trials should focus on Cilo treatment for secondary prevention of recurrent stroke in non-Asian patients. Copyright © 2016 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  4. External Validation of Risk Scores for Major Bleeding in a Population-Based Cohort of Transient Ischemic Attack and Ischemic Stroke Patients.

    PubMed

    Hilkens, Nina A; Li, Linxin; Rothwell, Peter M; Algra, Ale; Greving, Jacoba P

    2018-03-01

    The S 2 TOP-BLEED score may help to identify patients at high risk of bleeding on antiplatelet drugs after a transient ischemic attack or ischemic stroke. The score was derived on trial populations, and its performance in a real-world setting is unknown. We aimed to externally validate the S 2 TOP-BLEED score for major bleeding in a population-based cohort and to compare its performance with other risk scores for bleeding. We studied risk of bleeding in 2072 patients with a transient ischemic attack or ischemic stroke on antiplatelet agents in the population-based OXVASC (Oxford Vascular Study) according to 3 scores: S 2 TOP-BLEED, REACH, and Intracranial-B 2 LEED 3 S. Performance was assessed with C statistics and calibration plots. During 8302 patient-years of follow-up, 117 patients had a major bleed. The S 2 TOP-BLEED score showed a C statistic of 0.69 (95% confidence interval [CI], 0.64-0.73) and accurate calibration for 3-year risk of major bleeding. The S 2 TOP-BLEED score was much more predictive of fatal bleeding than nonmajor bleeding (C statistics 0.77; 95% CI, 0.69-0.85 and 0.50; 95% CI, 0.44-0.58). The REACH score had a C statistic of 0.63 (95% CI, 0.58-0.69) for major bleeding and the Intracranial-B 2 LEED 3 S score a C statistic of 0.60 (95% CI, 0.51-0.70) for intracranial bleeding. The ratio of ischemic events versus bleeds decreased across risk groups of bleeding from 6.6:1 in the low-risk group to 1.8:1 in the high-risk group. The S 2 TOP-BLEED score shows modest performance in a population-based cohort of patients with a transient ischemic attack or ischemic stroke. Although bleeding risks were associated with risks of ischemic events, risk stratification may still be useful to identify a subgroup of patients at particularly high risk of bleeding, in whom preventive measures are indicated. © 2018 The Authors.

  5. Lead exposure potentiates predatory attack behavior in the cat.

    PubMed

    Li, Wenjie; Han, Shenggao; Gregg, Thomas R; Kemp, Francis W; Davidow, Amy L; Louria, Donald B; Siegel, Allan; Bogden, John D

    2003-07-01

    Epidemiologic studies have demonstrated that environmental lead exposure is associated with aggressive behavior in children; however, numerous confounding variables limit the ability of these studies to establish a causal relationship. The study of aggressive behavior using a validated animal model was used to test the hypothesis that there is a causal relationship between lead exposure and aggression in the absence of confounding variables. We studied the effects of lead exposure on a feline model of aggression: predatory (quiet biting) attack of an anesthetized rat. Five cats were stimulated with a precisely controlled electrical current via electrodes inserted into the lateral hypothalamus. The response measure was the predatory attack threshold current (i.e., the current required to elicit an attack response on 50% of the trials). Blocks of trials were administered in which predatory attack threshold currents were measured three times a week for a total of 6-10 weeks, including before, during, and after lead exposure. Lead was incorporated into cat food "treats" at doses of 50-150 mg/kg/day. Two of the five cats received a second period of lead exposure. Blood lead concentrations were measured twice a week and were <1, 21-77, and <20 micro g/dL prior to, during, and after lead exposure, respectively. The predatory attack threshold decreased significantly during initial lead exposure in three of five cats and increased after the cessation of lead exposure in four of the five cats (P<0.01). The predatory attack thresholds and blood lead concentrations for each cat were inversely correlated (r=-0.35 to -0.74). A random-effects mixed model demonstrated a significant (P=0.0019) negative association between threshold current and blood lead concentration. The data of this study demonstrate that lead exposure enhances predatory aggression in the cat and provide experimental support for a causal relationship between lead exposure and aggressive behavior in humans.

  6. Management of acute attacks of hereditary angioedema: potential role of icatibant

    PubMed Central

    Longhurst, Hilary J

    2010-01-01

    Icatibant (Firazyr®) is a novel subcutaneous treatment recently licensed in the European Union for acute hereditary angioedema. Hereditary angioedema, resulting from inherited partial C1 inhibitor deficiency, is a disabling condition characterized by intermittent episodes of bradykinin-mediated angioedema. Icatibant blocks bradykinin B2 receptors, attenutating the episode. Randomized double-blind, placebo-controlled trials of icatibant, showed significant superiority over oral tranexamic acid in 74 European patients and a trend to improvement in a similar US trial comparing icatibant with placebo in 55 patients. Outcomes for several endpoints did not reach significance in the US trial, perhaps because of low participant numbers and confounding factors: a further trial is planned. Open label studies have shown benefit in multiple treatments for attacks at all sites. Approximately 10% of patients require a second dose for re-emergent symptoms, usually 10 to 27 hours after the initial treatment. Its subcutaneous route of administration, good tolerability and novel mode of action make icatibant a promising addition to the limited repertoire of treatments for hereditary angioedema. PMID:20859548

  7. A retrospective analysis of the protective efficacy of tafenoquine and mefloquine as prophylactic anti-malarials in non-immune individuals during deployment to a malaria-endemic area.

    PubMed

    Dow, Geoffrey S; McCarthy, William F; Reid, Mark; Smith, Bryan; Tang, Douglas; Shanks, G Dennis

    2014-02-06

    In 2000/2001, the Australian Defense Forces (ADF), in collaboration with SmithKline Beecham and the United States Army, conducted a field trial to evaluate the safety, tolerability and efficacy of tafenoquine and mefloquine/primaquine for the prophylaxis of malaria amongst non-immune Australian soldiers deployed to East Timor (now called Timor Leste) for peacekeeping operations. The lack of a concurrent placebo control arm prevented an internal estimate of the malaria attack rate and so the protective efficacy of the study regimens was not determined at the time. In a retrospective analysis of the trial results, the all species malaria attack rate was estimated for the prophylactic phase of the study which was defined as the period between administration of the first prophylactic dose and the first dose of post-deployment medication. First, the Plasmodium vivax attack rate was estimated during the prophylactic phase of the deployment by adjusting the observed P. vivax relapse rate during post-deployment to account for the known anti-relapse efficacies (or effectiveness) of the study medications (determined from prior studies). The all species malaria attack rate (P. vivax and Plasmodium falciparum) was then determined by adjusting the P. vivax attack rate based on the ratio of P. falciparum to P. vivax observed during prior ADF deployments to Timor Leste. This estimated all species malaria attack rate was then used as the 'constant estimated attack rate' in the calculation of the protective efficacy of tafenoquine and mefloquine during the prophylactic phase of the deployment. The estimated attack rate during the prophylactic phase of the study was determined to be 7.88%. The protective efficacies of tafenoquine and mefloquine, with corresponding 95% confidence intervals (95% CI), were determined to be 100% (93%-100%) and 100% (79%-100%) respectively. The protective efficacy of tafenoquine (200 mg per day for three days, followed by weekly 200 mg maintenance doses) is similar to that of the weekly standard of care (mefloquine, 250 mg).

  8. A retrospective analysis of the protective efficacy of tafenoquine and mefloquine as prophylactic anti-malarials in non-immune individuals during deployment to a malaria-endemic area

    PubMed Central

    2014-01-01

    Background In 2000/2001, the Australian Defense Forces (ADF), in collaboration with SmithKline Beecham and the United States Army, conducted a field trial to evaluate the safety, tolerability and efficacy of tafenoquine and mefloquine/primaquine for the prophylaxis of malaria amongst non-immune Australian soldiers deployed to East Timor (now called Timor Leste) for peacekeeping operations. The lack of a concurrent placebo control arm prevented an internal estimate of the malaria attack rate and so the protective efficacy of the study regimens was not determined at the time. Methods In a retrospective analysis of the trial results, the all species malaria attack rate was estimated for the prophylactic phase of the study which was defined as the period between administration of the first prophylactic dose and the first dose of post-deployment medication. First, the Plasmodium vivax attack rate was estimated during the prophylactic phase of the deployment by adjusting the observed P. vivax relapse rate during post-deployment to account for the known anti-relapse efficacies (or effectiveness) of the study medications (determined from prior studies). The all species malaria attack rate (P. vivax and Plasmodium falciparum) was then determined by adjusting the P. vivax attack rate based on the ratio of P. falciparum to P. vivax observed during prior ADF deployments to Timor Leste. This estimated all species malaria attack rate was then used as the ‘constant estimated attack rate’ in the calculation of the protective efficacy of tafenoquine and mefloquine during the prophylactic phase of the deployment. Results The estimated attack rate during the prophylactic phase of the study was determined to be 7.88%. The protective efficacies of tafenoquine and mefloquine, with corresponding 95% confidence intervals (95% CI), were determined to be 100% (93%-100%) and 100% (79%-100%) respectively. Conclusions The protective efficacy of tafenoquine (200 mg per day for three days, followed by weekly 200 mg maintenance doses) is similar to that of the weekly standard of care (mefloquine, 250 mg). PMID:24502679

  9. Comparative tolerability of treatments for acute migraine: A network meta-analysis.

    PubMed

    Thorlund, Kristian; Toor, Kabirraaj; Wu, Ping; Chan, Keith; Druyts, Eric; Ramos, Elodie; Bhambri, Rahul; Donnet, Anne; Stark, Richard; Goadsby, Peter J

    2017-09-01

    Introduction Migraine headache is a neurological disorder whose attacks are associated with nausea, vomiting, photophobia and phonophobia. Treatments for migraine aim to either prevent attacks before they have started or relieve attacks (abort) after onset of symptoms and range from complementary therapies to pharmacological interventions. A number of treatment-related adverse events such as somnolence, fatigue, and chest discomfort have previously been reported in association with triptans. The comparative tolerability of available agents for the abortive treatment of migraine attacks has not yet been systematically reviewed and quantified. Methods We performed a systematic literature review and Bayesian network meta-analysis for comparative tolerability of treatments for migraine. The literature search targeted all randomized controlled trials evaluating oral abortive treatments for acute migraine over a range of available doses in adults. The primary outcomes of interest were any adverse event, treatment-related adverse events, and serious adverse events. Secondary outcomes were fatigue, dizziness, chest discomfort, somnolence, nausea, and vomiting. Results Our search yielded 141 trials covering 15 distinct treatments. Of the triptans, sumatriptan, eletriptan, rizatriptan, zolmitriptan, and the combination treatment of sumatriptan and naproxen were associated with a statistically significant increase in odds of any adverse event or a treatment-related adverse event occurring compared with placebo. Of the non-triptans, only acetaminophen was associated with a statistically significant increase in odds of an adverse event occurring when compared with placebo. Overall, triptans were not associated with increased odds of serious adverse events occurring and the same was the case for non-triptans. For the secondary outcomes, with the exception of vomiting, all triptans except for almotriptan and frovatriptan were significantly associated with increased risk for all outcomes. Almotriptan was significantly associated with an increased risk of vomiting, whereas all other triptans yielded non-significant lower odds compared with placebo. Generally, the non-triptans were not associated with decreased tolerability for the secondary outcomes. Discussion In summary, triptans were associated with higher odds of any adverse event or a treatment-related adverse event occurring when compared to placebo and non-triptans. Non-significant results for non-triptans indicate that these treatments are comparable with one another and placebo regarding tolerability outcomes.

  10. Efficacy of a Community-Based Physical Activity Program KM2H2 for Stroke and Heart Attack Prevention among Senior Hypertensive Patients: A Cluster Randomized Controlled Phase-II Trial.

    PubMed

    Gong, Jie; Chen, Xinguang; Li, Sijian

    2015-01-01

    To evaluate the efficacy of the program Keep Moving toward Healthy Heart and Healthy Brain (KM2H2) in encouraging physical activities for the prevention of heart attack and stroke among hypertensive patients enrolled in the Community-Based Hypertension Control Program (CBHCP). Cluster randomized controlled trial with three waves of longitudinal assessments at baseline, 3 and 6 months post intervention. Community-based and patient-centered self-care for behavioral intervention in urban settings of China. A total of 450 participants diagnosed with hypertension from 12 community health centers in Wuhan, China were recruited, and were randomly assigned by center to receive either KM2H2 plus standard CBHCP care (6 centers and 232 patients) or the standard care only (6 centers and 218 patients). KM2H2 is a behavioral intervention guided by the Transtheoretical Model, the Model of Personalized Medicine and Social Capital Theory. It consists of six intervention sessions and two booster sessions engineered in a progressive manner. The purpose is to motivate and maintain physical activities for the prevention of heart attack and stroke. Heart attack and stroke (clinically diagnosed, primary outcome), blood pressure (measured, secondary outcome), and physical activity (self-report, tertiary outcome) were assessed at the individual level during the baseline, 3- and 6-month post-intervention. Relative to the standard care, receiving KM2H2 was associated with significant reductions in the incidence of heart attack (3.60% vs. 7.03%, p < .05) and stroke (5.11% vs. 9.90%, p<0.05), and moderate reduction in blood pressure (-3.72 mmHg in DBP and -2.92 mmHg in DBP) at 6-month post-intervention; and significant increases in physical activity at 3- (d = 0.53, 95% CI: 0.21, 0.85) and 6-month (d = 0.45, 95% CI: 0.04, 0.85) post-intervention, respectively. The program KM2H2 is efficacious to reduce the risk of heart attack and stroke among senior patients who are on anti-hypertensive medication. Findings of this study provide solid data supporting a formal phase-III trial to establish the effectiveness of KM2H2 for use in community settings for prevention. ISRCTN Register ISRCTN12608966.

  11. Tanacetum parthenium and Salix alba (Mig-RL) combination in migraine prophylaxis: a prospective, open-label study.

    PubMed

    Shrivastava, R; Pechadre, J C; John, G W

    2006-01-01

    Tanacetum parthenium (feverfew) has been used traditionally to treat migraine, and although its mechanism of action is not fully understood, serotonin 5-HT receptor blocking effects have been suggested. T. parthenium and Salix alba (white willow) either alone or in combination (Mig-RL) were recently shown to inhibit binding to 5-HT(2A/2C) receptors; T. parthenium failed to recognise 5-HT(1D) receptors, whereas S. alba or the combination did. It was hypothesised that S. alba in combination with T. parthenium may provide superior migraine prophylactic activity compared with T. parthenium alone. A prospective, open-label study was performed in 12 patients diagnosed with migraine without aura. Twelve weeks' treatment with T. parthenium 300 mg plus S. alba 300 mg (Mig-RL) twice daily was administered to determine the effects of therapy on migraine attack frequency (primary efficacy criterion), intensity and duration (secondary efficacy criteria), and quality of life, together with tolerability for patients. Attack frequency was reduced by 57.2% at 6 weeks (p < 0.029) and by 61.7% at 12 weeks (p < 0.025) in nine of ten patients, with 70% patients having a reduction of at least 50%. Attack intensity was reduced by 38.7% at 6 weeks (p < 0.005) and by 62.6% at 12 weeks (p < 0.004) in ten of ten patients, with 70% of patients having a reduction of at least 50%. Attack duration decreased by 67.2% at 6 weeks (p < 0.001) and by 76.2% at 12 weeks (p < 0.001) in ten of ten patients. Two patients were excluded for reasons unrelated to treatment. Self-assessed general health, physical performance, memory and anxiety also improved by the end of the study. Mig-RL treatment was well tolerated and no adverse events occurred. The remarkable efficacy of Mig-RL in not only reducing the frequency of migraine attacks but also their pain intensity and duration in this trial warrants further investigation of this therapy in a double-blind, randomised, placebo-controlled investigation involving a larger patient population.

  12. What is Metabolic Syndrome?

    MedlinePlus

    ... 22, 2012 | News Release NIH launches trial to evaluate anti-inflammatory treatment for preventing heart attacks, strokes, ... and Usage No FEAR Act Grants and Funding Customer Service/Center for Health Information Email Alerts Jobs ...

  13. Efficacy and safety of 400 and 800 mg etodolac vs. 1,000 mg paracetamol in acute treatment of migraine: a randomized, double-blind, crossover, multicenter, phase III clinical trial.

    PubMed

    Öztürk, Vesile; Ertaş, Mustafa; Baykan, Betül; Sirin, Hadiye; Özge, Aynur

    2013-03-01

    We aimed to determine the efficacy and safety of etodolac, in acute migraine attacks in comparison with paracetamol (acetaminophen). We designed a randomized, double-blind, crossover phase III clinical trial for patients diagnosed with migraine for at least 1 year, according to ICHD-II criteria. Two hundred and twenty-nine adult patients having 2 to 8 attacks monthly from 17 centers were included. The patients were instructed to use 3 attack treatment packages consisting of 1,000 mg paracetamol, 400 mg etodolac, and 800 mg etodolac on 3 migraine attacks of moderate-severe intensity each in a 3-month treatment period, interchangeably. Any pain medication was used in 1,570 migraine attacks while study treatments were used in 1,047 attacks. The results for 1,000 mg paracetamol, 400 mg etodolac, and 800 mg etodolac were as follows: response of headache at 2 hours 44.9%, 48.3% and 46.1%; pain-free at 2 hours 19.2%, 19.3% and 24.1%; sustained pain-free from 2 to 24 hours 34.3%, 38.3% and 41.1%; relapse rates in 2 to 24 hours 7.3%, 14.3% and 9.7%. There were no statistically significant differences between the groups regarding the headache response, pain-free, sustained pain-free, and relapse rates. Nausea, vomiting, phonophobia, or photophobia decreased similarly in all groups within 24 hours of treatment administration. Drug-related adverse events were noted in 8 patients with 1,000 mg paracetamol, in 9 patients with 400 mg etodolac and in 9 patients for 800 mg etodolac during the study. Our study showed that etodolac is a safe and effective alternative in acute migraine treatment and showed comparable efficacy to paracetamol 1,000 mg. Etodolac may be considered as an alternative option for acute treatment of migraine. © 2012 The Authors. Pain Practice © 2012 World Institute of Pain.

  14. Rationale and design of a randomized, double-blind, parallel-group study of terutroban 30 mg/day versus aspirin 100 mg/day in stroke patients: the prevention of cerebrovascular and cardiovascular events of ischemic origin with terutroban in patients with a history of ischemic stroke or transient ischemic attack (PERFORM) study.

    PubMed

    Bousser, M G; Amarenco, P; Chamorro, A; Fisher, M; Ford, I; Fox, K; Hennerici, M G; Mattle, H P; Rothwell, P M

    2009-01-01

    Ischemic stroke is the leading cause of mortality worldwide and a major contributor to neurological disability and dementia. Terutroban is a specific TP receptor antagonist with antithrombotic, antivasoconstrictive, and antiatherosclerotic properties, which may be of interest for the secondary prevention of ischemic stroke. This article describes the rationale and design of the Prevention of cerebrovascular and cardiovascular Events of ischemic origin with teRutroban in patients with a history oF ischemic strOke or tRansient ischeMic Attack (PERFORM) Study, which aims to demonstrate the superiority of the efficacy of terutroban versus aspirin in secondary prevention of cerebrovascular and cardiovascular events. The PERFORM Study is a multicenter, randomized, double-blind, parallel-group study being carried out in 802 centers in 46 countries. The study population includes patients aged > or =55 years, having suffered an ischemic stroke (< or =3 months) or a transient ischemic attack (< or =8 days). Participants are randomly allocated to terutroban (30 mg/day) or aspirin (100 mg/day). The primary efficacy endpoint is a composite of ischemic stroke (fatal or nonfatal), myocardial infarction (fatal or nonfatal), or other vascular death (excluding hemorrhagic death of any origin). Safety is being evaluated by assessing hemorrhagic events. Follow-up is expected to last for 2-4 years. Assuming a relative risk reduction of 13%, the expected number of primary events is 2,340. To obtain statistical power of 90%, this requires inclusion of at least 18,000 patients in this event-driven trial. The first patient was randomized in February 2006. The PERFORM Study will explore the benefits and safety of terutroban in secondary cardiovascular prevention after a cerebral ischemic event. Copyright 2009 S. Karger AG, Basel.

  15. Operational Test and Evaluation Handbook for Aircrew Training Devices. Volume II. Operational Effectiveness Evaluation

    DTIC Science & Technology

    1982-02-01

    should also convey an understanding of the differ- ences in learning behavior between initial learning activity and later skill maintenance and...refinement might then be, ATTACK MANEUVERS * Pop-up attack # Loft/ LADO type attack * Level/laydown attack Figure 5-4 showe diagrammatically the...sensitive to differ- ences in performance. Severai criteria should be used to guide the selection/development of performance measures, i.e., measure validity

  16. Passive Fingerprinting Of Computer Network Reconnaissance Tools

    DTIC Science & Technology

    2009-09-01

    v6 for version 6 MITM : Man-In-The-Middle Attack MSS: Maximum Segment Size NOP: No Operation Performed NPS: Naval Postgraduate School OS...specific, or man-in-the- middle ( MITM ) attacks. Depending on the attacker’s position to access the targeted network, the attacker may be able to...identification numbers. Both are ordinarily supposed to be initialized as a random number to make it difficult for an attacker to perform an injection MITM

  17. Quantum key distribution with hacking countermeasures and long term field trial.

    PubMed

    Dixon, A R; Dynes, J F; Lucamarini, M; Fröhlich, B; Sharpe, A W; Plews, A; Tam, W; Yuan, Z L; Tanizawa, Y; Sato, H; Kawamura, S; Fujiwara, M; Sasaki, M; Shields, A J

    2017-05-16

    Quantum key distribution's (QKD's) central and unique claim is information theoretic security. However there is an increasing understanding that the security of a QKD system relies not only on theoretical security proofs, but also on how closely the physical system matches the theoretical models and prevents attacks due to discrepancies. These side channel or hacking attacks exploit physical devices which do not necessarily behave precisely as the theory expects. As such there is a need for QKD systems to be demonstrated to provide security both in the theoretical and physical implementation. We report here a QKD system designed with this goal in mind, providing a more resilient target against possible hacking attacks including Trojan horse, detector blinding, phase randomisation and photon number splitting attacks. The QKD system was installed into a 45 km link of a metropolitan telecom network for a 2.5 month period, during which time the system operated continuously and distributed 1.33 Tbits of secure key data with a stable secure key rate over 200 kbit/s. In addition security is demonstrated against coherent attacks that are more general than the collective class of attacks usually considered.

  18. Effect of a traditional syrup from Citrus medica L. fruit juice on migraine headache: A randomized double blind placebo controlled clinical trial.

    PubMed

    Jafarpour, Mehrnaz; Yousefi, Gholamhossein; Hamedi, Azadeh; Shariat, Abdolhamid; Salehi, Alireza; Heydari, Mojtaba

    2016-02-17

    In Persian ethnomedicine several herbal remedies and functional foods have been used to treat migraine headache which are mostly summarized in Qarabadin-e-kabir (Aghili-Shirazi MH, 1773). One of them is Citron syrup (Sharbat-e-Balang) containing edible Citrus medica L. fruit juice and sugar. The present study was designed to assess the efficacy and safety of Citron syrup on patients with migraine headache. Citron syrup was prepared as described in Qarabadin-e-kabir. In this double blind randomized placebo-controlled clinical trial, ninety patients with migraine headache were allocated to three parallel groups (Citron syrup, propranolol or placebo). Patients received 15ml of Citron syrup, placebo syrup or 20mg of propranolol tablet three times daily after a meal for 4 weeks. Primary outcomes were obtained from three measures: the frequency (per month), mean duration (hour) and mean intensity (visual analogue scale "VAS" 0-10 score) of headache attacks evaluated prior to and following 4 weeks of the intervention. Citron syrup was superior to placebo in reduction of headache attacks intensity (P<0.01) and duration (p<0.0001) and as effective as propranolol in patients with migraine headache (P>0.05). However, unlike propranolol, Citron syrup could not significantly reduce the frequency of attacks compared to placebo. No indication of any serious side effects from Citron syrup was observed. According to obtained results, Citron syrup as a traditional Persian remedy can be suggested as an effective treatment for decreasing pain intensity and duration of attacks in migraine headache and the effectiveness is comparable to propranolol. However, the syrup did not show significant effect on frequency of attacks. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  19. Robust ECC-based authenticated key agreement scheme with privacy protection for Telecare medicine information systems.

    PubMed

    Zhang, Liping; Zhu, Shaohui

    2015-05-01

    To protect the transmission of the sensitive medical data, a secure and efficient authenticated key agreement scheme should be deployed when the healthcare delivery session is established via Telecare Medicine Information Systems (TMIS) over the unsecure public network. Recently, Islam and Khan proposed an authenticated key agreement scheme using elliptic curve cryptography for TMIS. They claimed that their proposed scheme is provably secure against various attacks in random oracle model and enjoys some good properties such as user anonymity. In this paper, however, we point out that any legal but malicious patient can reveal other user's identity. Consequently, their scheme suffers from server spoofing attack and off-line password guessing attack. Moreover, if the malicious patient performs the same time of the registration as other users, she can further launch the impersonation attack, man-in-the-middle attack, modification attack, replay attack, and strong replay attack successfully. To eliminate these weaknesses, we propose an improved ECC-based authenticated key agreement scheme. Security analysis demonstrates that the proposed scheme can resist various attacks and enables the patient to enjoy the remote healthcare services with privacy protection. Through the performance evaluation, we show that the proposed scheme achieves a desired balance between security and performance in comparisons with other related schemes.

  20. The effect of antihypertensive treatment on the incidence of stroke and cognitive decline in the elderly: a meta-analysis.

    PubMed

    Parsons, Christine; Murad, Mohammad Hassan; Andersen, Stuart; Mookadam, Farouk; Labonte, Helene

    2016-03-01

    To evaluate the effectiveness of antihypertensives in reducing neurocognitive outcomes in elderly patients. We conducted a systematic literature search of randomized trials in which hypertensive patients with a mean age ≥65 years received antihypertensive or control treatment. Outcomes were stroke, transient ischemic attack, cognitive decline and dementia. We included 14 trials for meta-analysis. Compared to placebo, antihypertensive treatment reduced the risk of stroke (RR: 0.67 [95% CI: 0.57-0.79]). Reduced risk was significant for transient ischemic attack, fatal stroke, nonfatal stroke and total stroke. There were insufficient data to compare individual agents. Antihypertensive treatment is associated with a significant reduction in stroke in elderly individuals. Reductions in dementia and cognitive decline were not significant; however, there was short follow-up. Comparative effectiveness evidence is limited.

  1. Effectiveness of icatibant for treatment of hereditary angioedema attacks is not affected by body weight: findings from the Icatibant Outcome Survey, a cohort observational study.

    PubMed

    Caballero, Teresa; Zanichelli, Andrea; Aberer, Werner; Maurer, Marcus; Longhurst, Hilary J; Bouillet, Laurence; Andresen, Irmgard

    2018-01-01

    Icatibant is a bradykinin B2-receptor antagonist used for the treatment of hereditary angioedema attacks resulting from C1-inhibitor deficiency. Treatment is not adjusted by body weight however the impact of body mass index (BMI) on the effectiveness of icatibant is not documented in the literature. We examined disease characteristics and icatibant treatment effectiveness in patients stratified by BMI in the Icatibant Outcome Survey, an ongoing, international, observational study monitoring the real-world safety and effectiveness of icatibant. Attack and treatment characteristics as well as outcomes following treatment with icatibant were compared among patients with underweight, normal, overweight, and obese BMI. Data from 2697 icatibant-treated attacks in 342 patients (3.5, 44.7, 34.8, and 17.0% patients of underweight, normal, overweight, and obese BMI, respectively) were analyzed. There was no significant difference in the frequency and severity of attacks across BMI groups, although obese patients tended to have more attacks of high severity. There was no impact of BMI on the frequency of laryngeal attacks, but patients with normal BMI had fewer cutaneous attacks and more abdominal attacks. Most attacks (71.9-83.8%) were treated with a single icatibant injection without the need for rescue with plasma-derived C1-inhibitor (pdC1-INH), regardless of BMI. Patients with obese BMI used pdC1-INH as rescue treatment more often (P < 0.0001; P = 0.0232 excluding 2 outliers) and treated attacks earlier than patients with normal BMI (P = 0.007). Furthermore, time to resolution and duration of attack were shorter for patients with high BMI (P < 0.001 for overweight and P < 0.05 for obese versus normal). Overall, icatibant was comparatively effective in treating attacks in patients across all BMI groups. Trial registration NCT01034969.

  2. Use of cannabis among 139 cluster headache sufferers.

    PubMed

    Leroux, Elizabeth; Taifas, Irina; Valade, Dominique; Donnet, Anne; Chagnon, Miguel; Ducros, Anne

    2013-02-01

    A case report suggested the efficacy of cannabis to treat cluster headache (CH) attacks. Our aims were to study the frequency of cannabis use in CH patients, and the reported effects on attacks. A total of 139 patients with CH attending two French headache centers filled out questionnaires. Sixty-three of the 139 patients (45.3%) had a history of cannabis use. As compared to nonusers, cannabis users were more likely to be younger (p < 0.001), male (p = 0.002) and tobacco smokers (p < 0.001). Among the 27 patients (19.4% of the total cohort) who had tried cannabis to treat CH attacks, 25.9% reported some efficacy, 51.8% variable or uncertain effects, and 22.3% negative effects. Cannabis use is very frequent in CH patients, but its efficacy for the treatment of the attacks is limited. Less than one third of self-reported users mention a relief of their attacks following inhalation. Cannabis should not be recommended for CH unless controlled trials with synthetic selective cannabinoids show a more convincing therapeutic benefit.

  3. SFTP: A Secure and Fault-Tolerant Paradigm against Blackhole Attack in MANET

    NASA Astrophysics Data System (ADS)

    KumarRout, Jitendra; Kumar Bhoi, Sourav; Kumar Panda, Sanjaya

    2013-02-01

    Security issues in MANET are a challenging task nowadays. MANETs are vulnerable to passive attacks and active attacks because of a limited number of resources and lack of centralized authority. Blackhole attack is an attack in network layer which degrade the network performance by dropping the packets. In this paper, we have proposed a Secure Fault-Tolerant Paradigm (SFTP) which checks the Blackhole attack in the network. The three phases used in SFTP algorithm are designing of coverage area to find the area of coverage, Network Connection algorithm to design a fault-tolerant model and Route Discovery algorithm to discover the route and data delivery from source to destination. SFTP gives better network performance by making the network fault free.

  4. Long-term prophylaxis in hereditary angio-oedema: a systematic review

    PubMed Central

    Casazza, Giovanni; Bossi, Ilaria; Duca, Piergiorgio; Cicardi, Marco

    2012-01-01

    Objective To systematically review the evidence regarding long-term prophylaxis in the prevention or reduction of attacks in hereditary angio-oedema (HAE). Design Systematic review and meta-analysis. Data sources Electronic databases were searched up to April 2011. Two reviewers selected the studies and extracted the study data, patient characteristics and outcomes of interest. Eligibility criteria for selected studies Controlled trials for HAE prophylaxis. Results 7 studies were included, for a total of 73 patients and 587 HAE attacks. Due to the paucity of studies, a meta-analysis was not possible. Since two studies did not report the number of HAE attacks, five studies (52 patients) were finally included in the summary analysis. Four classes of drugs with at least one controlled trial have been proposed for HAE prophylaxis. All those drugs, except heparin, were found to be more effective than placebo. In the absence of direct comparisons, the relative efficacies of these drugs were determined by calculating a RR of attacks (drug vs placebo). The results were as follows: danazol (RR=0.023, 95% CI 0.003 to 0.162), methyltestosterone (RR=0.054, 95% CI 0.013 to 0.163), ɛ-aminocaproic acid (RR=0.095, 95% CI 0.025 to 0.356), tranexamic acid (RR=0.308, 95% CI 0.195 to 0.479) and C1-INH 0.491 (95% CI 0.395 to 0.607). Conclusions Few trials have evaluated the benefits of HAE prophylaxis, and all drugs but heparin seem to be effective in this setting. Since there are no direct comparisons of HAE drugs, it was not possible to draw definitive conclusions on the most effective one. Thus, to accumulate evidence for HAE prophylaxis, further studies are needed that consider the dose–efficacy relationship and include a head-to-head comparison between drugs, with the active group, rather than placebo, as the control. PMID:22786946

  5. Diverticular Disease: Reconsidering Conventional Wisdom

    PubMed Central

    Peery, Anne F.; Sandler, Robert S.

    2013-01-01

    Colonic diverticula are common in developed countries and complications of colonic diverticulosis are responsible for a significant burden of disease. Several recent publications have called into question long held beliefs about diverticular disease. Contrary to conventional wisdom, studies have not shown that a high fiber diet protects against asymptomatic diverticulosis. The risk of developing diverticulitis among individuals with diverticulosis is lower than the 10–25% commonly quoted, and may be as low as 1% over 11 years. Nuts and seeds do not increase the risk of diverticulitis or diverticular bleeding. It is unclear whether diverticulosis, absent diverticulitis or overt colitis, is responsible for chronic gastrointestinal symptoms or worse quality of life. The role of antibiotics in acute diverticulitis has been challenged by a large randomized trial that showed no benefit in selected patients. The decision to perform elective surgery should be made on a case-by-case basis and not routinely after a second episode of diverticulitis, when there has been a complication, or in young people. A colonoscopy should be performed to exclude colon cancer after an attack of acute diverticulitis but may not alter outcomes among individuals who have had a colonoscopy prior to the attack. Given these surprising findings, it is time to reconsider conventional wisdom about diverticular disease. PMID:23669306

  6. Coherent attacking continuous-variable quantum key distribution with entanglement in the middle

    NASA Astrophysics Data System (ADS)

    Zhang, Zhaoyuan; Shi, Ronghua; Zeng, Guihua; Guo, Ying

    2018-06-01

    We suggest an approach on the coherent attack of continuous-variable quantum key distribution (CVQKD) with an untrusted entangled source in the middle. The coherent attack strategy can be performed on the double links of quantum system, enabling the eavesdropper to steal more information from the proposed scheme using the entanglement correlation. Numeric simulation results show the improved performance of the attacked CVQKD system in terms of the derived secret key rate with the controllable parameters maximizing the stolen information.

  7. Panic Attack History and Smoking Topography

    PubMed Central

    Farris, Samantha G.; Brown, Lily A.; Goodwin, Renee D.; Zvolensky, Michael J.

    2016-01-01

    Background Little is known about panic attacks and puffing topography, a behavioral index of the value of smoking reinforcement. This study examined smoking style during the course of smoking of a single cigarette among adult daily smokers with and without a history of panic attacks. Method Participants (n = 124, Mage = 43.9, SD = 9.7; 44.4% female) were non-treatment seeking daily smokers. Lifetime panic attack history was assessed via diagnostic assessment; 28.2% (n = 35) of the sample had a panic attack history. Participants smoked one cigarette during an ad libitum smoking trial. Puff volume, duration, and inter-puff interval were measured using the Clinical Research Support System (CReSS) pocket device. Results Regression analyses revealed that panic attack status was not associated with significant differences in average puff volume, duration, or inter-puff interval. Multi-level modeling was used to examine puffing trajectories. Puff-level data revealed that there was a significant quadratic time x panic effect for puff volume and duration. Those with a panic attack history demonstrated relatively sustained levels of both puff volume and duration over time, whereas those without a history of panic attacks demonstrated an increase followed by a decrease in volume and duration over time. These effects were not accounted for by the presence of general psychopathology. Discussion Smokers with a panic attack history demonstrate more persistent efforts to self-regulate the delivery of nicotine, and thus may be at risk for continued smoking and dependence. Tailored treatment may be needed to address unique vulnerabilities among this group. PMID:28033542

  8. Panic attack history and smoking topography.

    PubMed

    Farris, Samantha G; Brown, Lily A; Goodwin, Renee D; Zvolensky, Michael J

    2017-02-01

    Little is known about panic attacks and puffing topography, a behavioral index of the value of smoking reinforcement. This study examined smoking style during the course of smoking of a single cigarette among adult daily smokers with and without a history of panic attacks. Participants (n=124, M age =43.9, SD=9.7; 44.4% female) were non-treatment seeking daily smokers. Lifetime panic attack history was assessed via diagnostic assessment; 28.2% (n=35) of the sample had a panic attack history. Participants smoked one cigarette during an ad libitum smoking trial. Puff volume, duration, and inter-puff interval were measured using the Clinical Research Support System (CReSS) pocket device. Regression analyses revealed that panic attack status was not associated with significant differences in average puff volume, duration, or inter-puff interval. Multi-level modeling was used to examine puffing trajectories. Puff-level data revealed that there was a significant quadratic time x panic effect for puff volume and duration. Those with a panic attack history demonstrated relatively sustained levels of both puff volume and duration over time, whereas those without a history of panic attacks demonstrated an increase followed by a decrease in volume and duration over time. These effects were not accounted for by the presence of general psychopathology. Smokers with a panic attack history demonstrate more persistent efforts to self-regulate the delivery of nicotine, and thus may be at risk for continued smoking and dependence. Tailored treatment may be needed to address unique vulnerabilities among this group. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  9. Numerical investigation on the performance of fin and tube heat exchangers using rectangular vortex generators

    NASA Astrophysics Data System (ADS)

    Zeeshan, Mohd; Hazarika, Saheera Azmi; Nath, Sujit; Bhanja, Dipankar

    2017-07-01

    In the present work, a 3-D numerical investigation has been performed to explore the effect of attack angles on the thermal-hydraulic performance of fin and tube heat exchanger (FTHE) using rectangular winglet pairs (RWPs). RWPs are placed adjacent to the tubes and three attack angels are considered for the study i.e. 5°, 15° and 25°. The effect of attack angles are examined on the heat transfer characteristics as well as in pressure drop penalty with airside Reynolds number Rea ranges from 500 to 900. Two performance evaluation criteria namely PEC1 i.e. area goodness factor (j/f) and PEC2 i.e. heat transfer rate per unit fan power consumption (Q/Pf) are considered for the performance evaluation. Furthermore, MOORA method is applied to obtain the performance order of FTHE configurations by taking PEC1 and PEC2 as beneficial attributes and fan power Pf as a non-beneficial attribute, keeping equal importance to each attribute. The results show that 5° attack angle provides the better performance in terms of PEC1 as heat transfer coefficient is increased by 27.70% at Rea=500 and 32.73% at Rea=900 respectively with 13.01% increased pressure drop penalty at Rea=500 and 14.26% at Rea=900 respectively. In terms of PEC2, though the 5° attack angle provides the high values of Q/Pf factor among the 15° and 25° attack angles, but it is found insignificant to replace the baseline configuration i.e. plain fin and tube heat exchanger configuration without vortex generators. Moreover, in MOORA optimization analysis also, it is found that 5° attack angle provides the better thermal-hydraulic performance.

  10. Inflammation and neuropathic attacks in hereditary brachial plexus neuropathy

    PubMed Central

    Klein, C; Dyck, P; Friedenberg, S; Burns, T; Windebank, A; Dyck, P

    2002-01-01

    Objective: To study the role of mechanical, infectious, and inflammatory factors inducing neuropathic attacks in hereditary brachial plexus neuropathy (HBPN), an autosomal dominant disorder characterised by attacks of pain and weakness, atrophy, and sensory alterations of the shoulder girdle and upper limb muscles. Methods: Four patients from separate kindreds with HBPN were evaluated. Upper extremity nerve biopsies were obtained during attacks from a person of each kindred. In situ hybridisation for common viruses in nerve tissue and genetic testing for a hereditary tendency to pressure palsies (HNPP; tomaculous neuropathy) were undertaken. Two patients treated with intravenous methyl prednisolone had serial clinical and electrophysiological examinations. One patient was followed prospectively through pregnancy and during the development of a stereotypic attack after elective caesarean delivery. Results: Upper extremity nerve biopsies in two patients showed prominent perivascular inflammatory infiltrates with vessel wall disruption. Nerve in situ hybridisation for viruses was negative. There were no tomaculous nerve changes. In two patients intravenous methyl prednisolone ameliorated symptoms (largely pain), but with tapering of steroid dose, signs and symptoms worsened. Elective caesarean delivery did not prevent a typical postpartum attack. Conclusions: Inflammation, probably immune, appears pathogenic for some if not all attacks of HBPN. Immune modulation may be useful in preventing or reducing the neuropathic attacks, although controlled trials are needed to establish efficacy, as correction of the mutant gene is still not possible. The genes involved in immune regulation may be candidates for causing HBPN disorders. PMID:12082044

  11. Asynchronous threat awareness by observer trials using crowd simulation

    NASA Astrophysics Data System (ADS)

    Dunau, Patrick; Huber, Samuel; Stein, Karin U.; Wellig, Peter

    2016-10-01

    The last few years showed that a high risk of asynchronous threats is given in every day life. Especially in large crowds a high probability of asynchronous attacks is evident. High observational abilities to detect threats are desirable. Consequently highly trained security and observation personal is needed. This paper evaluates the effectiveness of a training methodology to enhance performance of observation personnel engaging in a specific target identification task. For this purpose a crowd simulation video is utilized. The study first provides a measurement of the base performance before the training sessions. Furthermore a training procedure will be performed. Base performance will then be compared to the after training performance in order to look for a training effect. A thorough evaluation of both the training sessions as well as the overall performance will be done in this paper. A specific hypotheses based metric is used. Results will be discussed in order to provide guidelines for the design of training for observational tasks.

  12. Simulation of Attacks for Security in Wireless Sensor Network.

    PubMed

    Diaz, Alvaro; Sanchez, Pablo

    2016-11-18

    The increasing complexity and low-power constraints of current Wireless Sensor Networks (WSN) require efficient methodologies for network simulation and embedded software performance analysis of nodes. In addition, security is also a very important feature that has to be addressed in most WSNs, since they may work with sensitive data and operate in hostile unattended environments. In this paper, a methodology for security analysis of Wireless Sensor Networks is presented. The methodology allows designing attack-aware embedded software/firmware or attack countermeasures to provide security in WSNs. The proposed methodology includes attacker modeling and attack simulation with performance analysis (node's software execution time and power consumption estimation). After an analysis of different WSN attack types, an attacker model is proposed. This model defines three different types of attackers that can emulate most WSN attacks. In addition, this paper presents a virtual platform that is able to model the node hardware, embedded software and basic wireless channel features. This virtual simulation analyzes the embedded software behavior and node power consumption while it takes into account the network deployment and topology. Additionally, this simulator integrates the previously mentioned attacker model. Thus, the impact of attacks on power consumption and software behavior/execution-time can be analyzed. This provides developers with essential information about the effects that one or multiple attacks could have on the network, helping them to develop more secure WSN systems. This WSN attack simulator is an essential element of the attack-aware embedded software development methodology that is also introduced in this work.

  13. Cougar attacks on children: injury patterns and treatment.

    PubMed

    Kadesky, K M; Manarey, C; Blair, G K; Murphy, J J; Verchere, C; Atkinson, K

    1998-06-01

    Cougar attacks on humans appear to be on the rise. A review of all attacks on children was performed to determine the method of attack and injury patterns so that a treatment regimen as well as possible preventative measures could be determined. A review of all attacks, including attacks on children, was performed, including three recent attacks treated at our institution. Situation, adult supervision, patient age, injuries recorded, survival, and mode of attack, if known, were reviewed. There were 50 documented attacks on children with a 25% fatality rate. Most children were not alone at the time of the attack (92%), and in many instances adult supervision was present or nearby. Severe head and neck lacerations along with puncture wounds were the most common injury. Examples of typical cervical injuries include a nonfatal vertebral artery injury, phrenic nerve injury, a fatal internal carotid artery injury, and a fatal cervical spine injury. The cougar was rabid in two cases. Pasteurella resulted in late infections in two patients. Based on the pattern of injuries, the authors recommend aggressive evaluation for occult cervical injuries as well as surgical debridement. Antibiotics should cover oropharyngeal flora including Pasteurella multocida. Rabies prophylaxis is indicated. Adult supervision in wilderness areas is not necessarily protective.

  14. EVALUATION OF THE CHANGES IN THE NASAL CAVITY DURING THE MIGRAINE ATTACK

    PubMed Central

    Arslan, H. Hüseyin; Tokgöz, Erkan; Yıldızoğlu, Üzeyir; Durmaz, Abdullah; Bek, Semai; Gerek, Mustafa

    2012-01-01

    Objectives There are some subjective symptoms involving the nasal cavity such as nasal congestion during a migraine attack. In this study, we aimed to evaluate the possible changes occuring in the nasal cavity, during headache in migraine patients. Material and Methods Subjects with migraine were studied. The control group was consisted with tension-type headache patients. The severity of the headache and accompanying complaints were assessed by visual analog scale, and nasal mucosa was assessed by anterior rhinoscopy and endoscopy. Resistance of the nasal cavity was evaluated with anterior rhinomanometry. The data obtained during the attack periods and attack free periods were compared. Results 25 migraine patients and 15 tension-type headache patients were enrolled. It was found that 19 subjects (%76) of migraine group and 5 of tension-type headache group were suffering from nasal congestion during the attack, and that the differences between the groups were statistically significant (p<0.05). The average of total nasal resistance in migraine patients was 0,57±0,60 kPa/L/sn during migraine attacks and 0,28±0,14 kPa/L/sn during attack free periods. The average of total nasal resistance in tension-type headache patients was 0,32±0,14 kPa/L/sn during attack periods and 0,31±0,20 kPa/L/sn during attack free periods. In the migraine group, the change of nasal resistance between during the attack and attack free periods was found statistically significant, while there was no statistically significant difference in the tension-type headache group. Conclusion According to the results of this study, complaining of nasal obstruction and nasal airway resistance increases during migraine attacks. Cause and effect relationship between nasal obstruction and pain is not clear and clinical trials are needed to determine the effect of nasal obstruction treatment (mucosal decongestion etc.) on the complaint of pain. PMID:25072974

  15. 39 CFR 501.11 - Reporting Postage Evidencing System security weaknesses.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... any repeatable deviation from normal Postage Evidencing System performance. (3) Cyber attacks that... misappropriating assets or sensitive information, corrupting data, or causing operational disruption. Cyber attacks... causing denial-of-service attacks on Web sites. Cyber attacks may be carried out by third parties or...

  16. 39 CFR 501.11 - Reporting Postage Evidencing System security weaknesses.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... any repeatable deviation from normal Postage Evidencing System performance. (3) Cyber attacks that... misappropriating assets or sensitive information, corrupting data, or causing operational disruption. Cyber attacks... causing denial-of-service attacks on Web sites. Cyber attacks may be carried out by third parties or...

  17. 39 CFR 501.11 - Reporting Postage Evidencing System security weaknesses.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... any repeatable deviation from normal Postage Evidencing System performance. (3) Cyber attacks that... misappropriating assets or sensitive information, corrupting data, or causing operational disruption. Cyber attacks... causing denial-of-service attacks on Web sites. Cyber attacks may be carried out by third parties or...

  18. Clinical trial investigates experimental drug for advanced pancreatic cancer | Center for Cancer Research

    Cancer.gov

    The pancreas, a large gland that sits behind the stomach, produces enzymes that aid digestion and hormones that regulate blood sugar. Pancreatic cancer develops when cells that make up the ducts in the pancreas start to grow out of control. Udo Rudloff, M.D., is leading a clinical trial of a combination immunotherapy regimen to optimally help the immune system attack the tumor.

  19. Health and cost benefits associated with the use of metoprolol in heart attack patients.

    PubMed

    Fernández-Jiménez, Rodrigo; Ibanez, Borja

    2014-11-01

    Heart attack (myocardial infarction) is a highly prevalent entity worldwide. Widespread implementation of reperfusion strategies has dramatically reduced the mortality associated with infarction. Paradoxically, the mortality reduction has significantly increased the incidence of chronic heart failure (HF). Treatment of HF, once present, represents a huge socioeconomic burden on individuals and healthcare systems. The possibility of preventing rather than treating post-infarction HF would be of paramount importance. Given that infarct size is the main determinant of adverse post-infarction outcomes (including chronic HF), therapies able to reduce infarct size are needed. The single administration of intravenous metoprolol before reperfusion has been recently shown to reduce infarct size and reduce the cases of chronic HF in a proof-of-concept trial. If confirmed in larger trials, this low-cost therapy is expected to have a major health and socioeconomic impact.

  20. Dolichoectasia and Small Vessel Disease in Young Patients With Transient Ischemic Attack and Stroke.

    PubMed

    Thijs, Vincent; Grittner, Ulrike; Fazekas, Franz; McCabe, Dominick J H; Giese, Anne-Katrin; Kessler, Christof; Martus, Peter; Norrving, Bo; Ringelstein, Erich Bernd; Schmidt, Reinhold; Tanislav, Christian; Putaala, Jukka; Tatlisumak, Turgut; von Sarnowski, Bettina; Rolfs, Arndt; Enzinger, Christian

    2017-09-01

    We evaluated whether basilar dolichoectasia is associated with markers of cerebral small vessel disease in younger transient ischemic attack and ischemic stroke patients. We used data from the SIFAP1 study (Stroke in Young Fabry Patients), a large prospective, hospital-based, screening study for Fabry disease in young (<55 years) transient ischemic attack/stroke patients in whom detailed clinical data and brain MRI were obtained, and stroke subtyping with TOAST classification (Trial of ORG 10172 in Acute Stroke Treatment) was performed. Dolichoectasia was found in 508 of 3850 (13.2%) of patients. Dolichoectasia was associated with older age (odds ratio per decade, 1.26; 95% confidence interval, 1.09-1.44), male sex (odds ratio, 1.96; 95% confidence interval, 1.59-2.42), and hypertension (odds ratio, 1.39; 95% confidence interval, 1.13-1.70). Dolichoectasia was more common in patients with small infarctions (33.9% versus 29.8% for acute lesions, P =0.065; 29.1% versus 16.5% for old lesions, P <0.001), infarct location in the brain stem (12.4% versus 6.9%, P <0.001), and in white matter (27.8% versus 21.1%, P =0.001). Microbleeds (16.3% versus 4.7%, P =0.001), higher grades of white matter hyperintensities ( P <0.001), and small vessel disease subtype (18.1% versus 12.4%, overall P for differences in TOAST ( P =0.018) were more often present in patients with dolichoectasia. Dolichoectasia is associated with imaging markers of small vessel disease and brain stem localization of acute and old infarcts in younger patients with transient ischemic attack and ischemic stroke. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00414583. © 2017 American Heart Association, Inc.

  1. Cluster headache: clinical features and therapeutic options.

    PubMed

    Gaul, Charly; Diener, Hans-Christoph; Müller, Oliver M

    2011-08-01

    Cluster headache is the most common type of trigemino-autonomic headache, affecting ca. 120 000 persons in Germany alone. The attacks of pain are in the periorbital area on one side, last 90 minutes on average, and are accompanied by trigemino-autonomic manifestations and restlessness. Most patients have episodic cluster headache; about 15% have chronic cluster headache, with greater impairment of their quality of life. The attacks often possess a circadian and seasonal rhythm. Selective literature review Oxygen inhalation and triptans are effective acute treatment for cluster attacks. First-line drugs for attack prophylaxis include verapamil and cortisone; alternatively, lithium and topiramate can be given. Short-term relief can be obtained by the subcutaneous infiltration of local anesthetics and steroids along the course of the greater occipital nerve, although most of the evidence in favor of this is not derived from randomized clinical trials. Patients whose pain is inadequately relieved by drug treatment can be offered newer, invasive treatments, such as deep brain stimulation in the hypothalamus (DBS) and bilateral occipital nerve stimulation (ONS). Pharmacotherapy for the treatment of acute attacks and for attack prophylaxis is effective in most patients. For the minority who do not gain adequate relief, newer invasive techniques are available in some referral centers. Definitive conclusions as to their value cannot yet be drawn from the available data.

  2. Cyber attack analysis on cyber-physical systems: Detectability, severity, and attenuation strategy

    NASA Astrophysics Data System (ADS)

    Kwon, Cheolhyeon

    Security of Cyber-Physical Systems (CPS) against malicious cyber attacks is an important yet challenging problem. Since most cyber attacks happen in erratic ways, it is usually intractable to describe and diagnose them systematically. Motivated by such difficulties, this thesis presents a set of theories and algorithms for a cyber-secure architecture of the CPS within the control theoretic perspective. Here, instead of identifying a specific cyber attack model, we are focused on analyzing the system's response during cyber attacks. Firstly, we investigate the detectability of the cyber attacks from the system's behavior under cyber attacks. Specifically, we conduct a study on the vulnerabilities in the CPS's monitoring system against the stealthy cyber attack that is carefully designed to avoid being detected by its detection scheme. After classifying three kinds of cyber attacks according to the attacker's ability to compromise the system, we derive the necessary and sufficient conditions under which such stealthy cyber attacks can be designed to cause the unbounded estimation error while not being detected. Then, the analytical design method of the optimal stealthy cyber attack that maximizes the estimation error is developed. The proposed stealthy cyber attack analysis is demonstrated with illustrative examples on Air Traffic Control (ATC) system and Unmanned Aerial Vehicle (UAV) navigation system applications. Secondly, in an attempt to study the CPSs' vulnerabilities in more detail, we further discuss a methodology to identify potential cyber threats inherent in the given CPSs and quantify the attack severity accordingly. We then develop an analytical algorithm to test the behavior of the CPS under various cyber attack combinations. Compared to a numerical approach, the analytical algorithm enables the prediction of the most effective cyber attack combinations without computing the severity of all possible attack combinations, thereby greatly reducing the computational cost. The proposed algorithm is validated through a linearized longitudinal motion of a UAV example. Finally, we propose an attack attenuation strategy via the controller design for CPSs that are robust to various types of cyber attacks. While the previous studies have investigated a secure control by assuming a specific attack strategy, in this research we propose a hybrid robust control scheme that contains multiple sub-controllers, each matched to a specific type of cyber attacks. Then the system can be adapted to various cyber attacks (including those that are not assumed for sub-controller design) by switching its sub-controllers to achieve the best performance. Then, a method for designing a secure switching logic to counter all possible cyber attacks is proposed and it verifies mathematically the system's performance and stability as well. The performance of the proposed control scheme is demonstrated by an example with the hybrid H2 - H-infinity controller applied to a UAV example.

  3. Oral clonidine for proctalgia fugax.

    PubMed

    Swain, R

    1987-08-01

    A report is made of the successful use of oral clonidine for proctalgia fugax by the author on himself. The author, a 30 year old otherwise healthy man, has been having attacks of proctalgia fugax for several years. He had hitherto left the condition untreated. Last year, in a severe attack, he tried oral clonidine 150 micrograms twice a day and found it to be dramatically effective. He was completely relieved in three days and tapered off the drug thereafter. A further attack of proctalgia fugax after a month was again treated successfully with oral clonidine. The presumed aetiology of proctalgia fugax is discussed and the possible mechanism of action of clonidine in this condition is outlined. Further trials of clonidine appear to be worthwhile for this condition which has been described as incurable.

  4. Oral clonidine for proctalgia fugax.

    PubMed Central

    Swain, R

    1987-01-01

    A report is made of the successful use of oral clonidine for proctalgia fugax by the author on himself. The author, a 30 year old otherwise healthy man, has been having attacks of proctalgia fugax for several years. He had hitherto left the condition untreated. Last year, in a severe attack, he tried oral clonidine 150 micrograms twice a day and found it to be dramatically effective. He was completely relieved in three days and tapered off the drug thereafter. A further attack of proctalgia fugax after a month was again treated successfully with oral clonidine. The presumed aetiology of proctalgia fugax is discussed and the possible mechanism of action of clonidine in this condition is outlined. Further trials of clonidine appear to be worthwhile for this condition which has been described as incurable. PMID:3666555

  5. Flowing water affects fish fast-starts: escape performance of the Hawaiian stream goby, Sicyopterus stimpsoni.

    PubMed

    Diamond, Kelly M; Schoenfuss, Heiko L; Walker, Jeffrey A; Blob, Richard W

    2016-10-01

    Experimental measurements of escape performance in fishes have typically been conducted in still water; however, many fishes inhabit environments with flow that could impact escape behavior. We examined the influences of flow and predator attack direction on the escape behavior of fish, using juveniles of the amphidromous Hawaiian goby Sicyopterus stimpsoni In nature, these fish must escape ambush predation while moving through streams with high-velocity flow. We measured the escape performance of juvenile gobies while exposing them to a range of water velocities encountered in natural streams and stimulating fish from three different directions. Frequency of response across treatments indicated strong effects of flow conditions and attack direction. Juvenile S. stimpsoni had uniformly high response rates for attacks from a caudal direction (opposite flow); however, response rates for attacks from a cranial direction (matching flow) decreased dramatically as flow speed increased. Mechanical stimuli produced by predators attacking in the same direction as flow might be masked by the flow environment, impairing the ability of prey to detect attacks. Thus, the likelihood of successful escape performance in fishes can depend critically on environmental context. © 2016. Published by The Company of Biologists Ltd.

  6. Treatment of proctalgia fugax with salbutamol inhalation.

    PubMed

    Eckardt, V F; Dodt, O; Kanzler, G; Bernhard, G

    1996-04-01

    Although no generally effective treatment for proctalgia fugax is known, inhalation of salbutamol has been reported to shorten pain attacks in isolated cases. We conducted a randomized, double-blind, placebo-controlled, crossover trial of inhaled salbutamol in 18 patients with proctalgia fugax. The clinical effect was evaluated by recording the duration of severe pain and discomfort during acute attacks. In addition, anorectal motility recordings were analyzed for possible changes in anal resting tone, sphincter relaxation during rectal distension and in rectal compliance prior to and following administration of the two test substances. Sixteen patients completed all investigations. Compared to placebo, salbutamol inhalation shortened the duration of severe pain (p = 0.019). The effect was most marked in patients having prolonged attacks. In the asymptomatic state, neither salbutamol nor placebo led to a significant change in anal resting pressure, anal relaxation during rectal distension, or rectal compliance. Salbutamol also did not alter the threshold for rectal sensation. Salbutamol inhalation shortens attacks of severe pain in patients with proctalgia fugax. The mechanism of this effect remains unexplained.

  7. Electrocardiographic measures of left ventricular hypertrophy in the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial.

    PubMed

    Ernst, Michael E; Davis, Barry R; Soliman, Elsayed Z; Prineas, Ronald J; Okin, Peter M; Ghosh, Alokananda; Cushman, William C; Einhorn, Paula T; Oparil, Suzanne; Grimm, Richard H

    2016-12-01

    Left ventricular hypertrophy (LVH) predicts cardiovascular risk in hypertensive patients. We analyzed baseline/follow-up electrocardiographies in 26,376 Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial participants randomized to amlodipine (A), lisinopril (L), or chlorthalidone (C). Prevalent/incident LVH was examined using continuous and categorical classifications of Cornell voltage. At 2 and 4 years, prevalence of LVH in the C group (5.57%; 6.14%) was not statistically different from A group (2 years: 5.47%; P = .806, 4 years: 6.54%; P = .857) or L group (2 years: 5.64%; P = .857, 4 years: 6.50%; P = .430). Incident LVH followed similarly, with no difference at 2 years for C (2.99%) compared to A (2.57%; P = .173) or L (3.16%; P = .605) and at 4 years (C = 3.52%, A = 3.29%, L = 3.71%; P = .521 C vs. A, P = .618 C vs. L). Mean Cornell voltage decreased comparably across treatment groups (Δ baseline, 2 years = +3 to -27 μV, analysis of variance P = .8612; 4 years = +10 to -17 μV, analysis of variance P = .9692). We conclude that risk reductions associated with C treatment in secondary end points of the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial cannot be attributed to differential improvements in electrocardiography LVH. Copyright © 2016 American Society of Hypertension. All rights reserved.

  8. Nonlinear dynamics of team performance and adaptability in emergency response.

    PubMed

    Guastello, Stephen J

    2010-04-01

    The impact of team size and performance feedback on adaptation levels and performance of emergency response (ER) teams was examined to introduce a metric for quantifying adaptation levels based on nonlinear dynamical systems (NDS) theory. NDS principles appear in reports surrounding Hurricane Katrina, earthquakes, floods, a disease epidemic, and the Southeast Asian tsunami. They are also intrinsic to coordination within teams, adaptation levels, and performance in dynamic decision processes. Performance was measured in a dynamic decision task in which ER teams of different sizes worked against an attacker who was trying to destroy a city (total N = 225 undergraduates). The complexity of teams' and attackers' adaptation strategies and the role of the opponents' performance were assessed by nonlinear regression analysis. An optimal group size for team performance was identified. Teams were more readily influenced by the attackers' performance than vice versa. The adaptive capabilities of attackers and teams were impaired by their opponents in some conditions. ER teams should be large enough to contribute a critical mass of ideas but not so large that coordination would be compromised. ER teams used self-organized strategies that could have been more adaptive, whereas attackers used chaotic strategies. The model and results are applicable to ER processes or training maneuvers involving dynamic decisions but could be limited to nonhierarchical groups.

  9. Simulation of Attacks for Security in Wireless Sensor Network

    PubMed Central

    Diaz, Alvaro; Sanchez, Pablo

    2016-01-01

    The increasing complexity and low-power constraints of current Wireless Sensor Networks (WSN) require efficient methodologies for network simulation and embedded software performance analysis of nodes. In addition, security is also a very important feature that has to be addressed in most WSNs, since they may work with sensitive data and operate in hostile unattended environments. In this paper, a methodology for security analysis of Wireless Sensor Networks is presented. The methodology allows designing attack-aware embedded software/firmware or attack countermeasures to provide security in WSNs. The proposed methodology includes attacker modeling and attack simulation with performance analysis (node’s software execution time and power consumption estimation). After an analysis of different WSN attack types, an attacker model is proposed. This model defines three different types of attackers that can emulate most WSN attacks. In addition, this paper presents a virtual platform that is able to model the node hardware, embedded software and basic wireless channel features. This virtual simulation analyzes the embedded software behavior and node power consumption while it takes into account the network deployment and topology. Additionally, this simulator integrates the previously mentioned attacker model. Thus, the impact of attacks on power consumption and software behavior/execution-time can be analyzed. This provides developers with essential information about the effects that one or multiple attacks could have on the network, helping them to develop more secure WSN systems. This WSN attack simulator is an essential element of the attack-aware embedded software development methodology that is also introduced in this work. PMID:27869710

  10. Invisible Trojan-horse attack.

    PubMed

    Sajeed, Shihan; Minshull, Carter; Jain, Nitin; Makarov, Vadim

    2017-08-21

    We demonstrate the experimental feasibility of a Trojan-horse attack that remains nearly invisible to the single-photon detectors employed in practical quantum key distribution (QKD) systems, such as Clavis2 from ID Quantique. We perform a detailed numerical comparison of the attack performance against Scarani-Ac´ın-Ribordy-Gisin (SARG04) QKD protocol at 1924 nm versus that at 1536 nm. The attack strategy was proposed earlier but found to be unsuccessful at the latter wavelength, as reported in N. Jain et al., New J. Phys. 16, 123030 (2014). However at 1924 nm, we show experimentally that the noise response of the detectors to bright pulses is greatly reduced, and show by modeling that the same attack will succeed. The invisible nature of the attack poses a threat to the security of practical QKD if proper countermeasures are not adopted.

  11. Distribution of attack by beech scale, Cryptococcus fagisuga, in beech progeny trials

    Treesearch

    D. Wainhouse; R.S. Howell

    1983-01-01

    Surveys of beech scale infestation among progeny of single beech trees demonstrated significant variation in susceptibility between the progenies. Relative differences in susceptibility of some progeny were maintained on three different sites in southern England.

  12. Timing of prophylactic surgery in prevention of diverticulitis recurrence: a cost-effectiveness analysis.

    PubMed

    Richards, Robert J; Hammitt, James K

    2002-09-01

    Although surgery is recommended after two or more attacks of uncomplicated diverticulitis, the optimal timing for surgery in terms of cost-effectiveness is unknown. A Markov model was used to compare the costs and outcomes of performing surgery after one, two, or three uncomplicated attacks in 60-year-old hypothetical cohorts. Transition state probabilities were assigned values using published data and expert opinion. Costs were estimated from Medicare reimbursement rates. Surgery after the third attack is cost saving, yielding more years of life and quality adjusted life years at a lower cost than the other two strategies. The results were not sensitive to many of the variables tested in the model or to changes made in the discount rate (0-5%). In conclusion, performing prophylactic resection after the third attack of diverticulitis is cost saving in comparison to resection performed after the first or second attacks and remains cost-effective during sensitivity analysis.

  13. Long-Term Follow-up of Participants with Heart Failure in the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT)

    PubMed Central

    Piller, Linda B.; Baraniuk, Sarah; Simpson, Lara M.; Cushman, William C.; Massie, Barry M.; Einhorn, Paula T.; Oparil, Suzanne; Ford, Charles E.; Graumlich, James F.; Dart, Richard A.; Parish, David C.; Retta, Tamrat M.; Cuyjet, Aloysius B.; Jafri, Syed Z.; Furberg, Curt D.; Saklayen, Mohammad G.; Thadani, Udho; Probstfield, Jeffrey L.; Davis, Barry R.

    2011-01-01

    Background In the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT), a randomized, double-blind, practice-based, active-control, comparative effectiveness trial in high-risk hypertensive participants, risk of new-onset heart failure (HF) was higher in the amlodipine (2.5-10 mg/day) and lisinopril (10-40 mg/day) arms compared with the chlorthalidone (12.5-25 mg/day) arm . Similar to other studies, mortality rates following new-onset HF were very high (≥50% at 5 years), and were similar across randomized treatment arms. After the randomized phase of the trial ended in 2002, outcomes were determined from administrative databases. Methods and Results Using national databases, post-trial follow-up mortality through 2006 was obtained on participants who developed new-onset HF during the randomized (in-trial) phase of ALLHAT. Mean follow-up for the entire period was 8.9 years. Of 1761 participants with incident HF in-trial, 1348 died. Post-HF all-cause mortality was similar across treatment groups with adjusted hazard ratios (95% confidence intervals) of 0.95 (0.81-1.12) and 1.05 (0.89-1.25), respectively, for amlodipine and lisinopril compared with chlorthalidone, and 10-year adjusted rates of 86%, 87%, and 83%, respectively. All-cause mortality rates were also similar among those with reduced ejection fractions (84%) and preserved ejection fractions (81%) with no significant differences by randomized treatment arm. Conclusions Once HF develops, risk of death is high and consistent across randomized treatment groups. Measures to prevent the development of HF, especially blood pressure control, must be a priority if mortality associated with development of HF is to be addressed. PMID:21969009

  14. Improved statistical analysis of moclobemide dose effects on panic disorder treatment.

    PubMed

    Ross, Donald C; Klein, Donald F; Uhlenhuth, E H

    2010-04-01

    Clinical trials with several measurement occasions are frequently analyzed using only the last available observation as the dependent variable [last observation carried forward (LOCF)]. This ignores intermediate observations. We reanalyze, with complete data methods, a clinical trial previously reported using LOCF, comparing placebo and five dosage levels of moclobemide in the treatment of outpatients with panic disorder to illustrate the superiority of methods using repeated observations. We initially analyzed unprovoked and situational, major and minor attacks as the four dependent variables, by repeated measures maximum likelihood methods. The model included parameters for linear and curvilinear time trends and regression of measures during treatment on baseline measures. Significance tests using this method take into account the structure of the error covariance matrix. This makes the sphericity assumption irrelevant. Missingness is assumed to be unrelated to eventual outcome and the residuals are assumed to have a multivariate normal distribution. No differential treatment effects for limited attacks were found. Since similar results were obtained for both types of major attack, data for the two types of major attack were combined. Overall downward linear and negatively accelerated downward curvilinear time trends were found. There were highly significant treatment differences in the regression slopes of scores during treatment on baseline observations. For major attacks, all treatment groups improved over time. The flatter regression slopes, obtained with higher doses, indicated that higher doses result in uniformly lower attack rates regardless of initial severity. Lower doses do not lower the attack rate of severely ill patients to those achieved in the less severely ill. The clinical implication is that more severe patients require higher doses to attain best benefit. Further, the significance levels obtained by LOCF analyses were only in the 0.05-0.01 range, while significance levels of <0.00001 were obtained by these repeated measures analyses indicating increased power. The greater sensitivity to treatment effect of this complete data method is illustrated. To increase power, it is often recommended to increase sample size. However, this is often impractical since a major proportion of the cost per subject is due to the initial evaluation. Increasing the number of repeated observations increases power economically and also allows detailed longitudinal trajectory analyses.

  15. Gamma knife treatment for refractory cluster headache: prospective open trial.

    PubMed

    Donnet, A; Valade, D; Régis, J

    2005-02-01

    Since the initial report of Ford et al in 1998 no further study has evaluated radiosurgery of the trigeminal nerve in chronic cluster headache (CCH). We carried out a prospective open trial of neurosurgery and enrolled 10 patients (nine men, one woman; mean age 49.8 years, range 32-77) presenting with severe and drug resistant CCH (mean duration 9 years, range 2-33). The cisternal segment of the nerve was targeted with a single 4 mm collimator (80-85 Gy max). The mean follow up was 13.2 months. No improvement was observed in two patients and three patients had no further attacks. Three patients showed dramatic improvement with a few attacks per month or very few attacks over the last six months. Two patients were pain free for only one and two weeks and their headaches recurred with the same severity as before. Three patients developed paraesthesia with no hypoaesthesia, one developed hypoaesthesia, and one developed deafferentation pain. The rate and severity of trigeminal nerve injury appeared to be significantly higher than in trigeminal neuralgia, and this study does not support the positive results of the study of Ford et al. We consider the morbidity to be significant for the low rate of pain cessation, making this procedure less attractive even for the more severely affected subgroup of patients.

  16. Informatic analysis for hidden pulse attack exploiting spectral characteristics of optics in plug-and-play quantum key distribution system

    NASA Astrophysics Data System (ADS)

    Ko, Heasin; Lim, Kyongchun; Oh, Junsang; Rhee, June-Koo Kevin

    2016-10-01

    Quantum channel loopholes due to imperfect implementations of practical devices expose quantum key distribution (QKD) systems to potential eavesdropping attacks. Even though QKD systems are implemented with optical devices that are highly selective on spectral characteristics, information theory-based analysis about a pertinent attack strategy built with a reasonable framework exploiting it has never been clarified. This paper proposes a new type of trojan horse attack called hidden pulse attack that can be applied in a plug-and-play QKD system, using general and optimal attack strategies that can extract quantum information from phase-disturbed quantum states of eavesdropper's hidden pulses. It exploits spectral characteristics of a photodiode used in a plug-and-play QKD system in order to probe modulation states of photon qubits. We analyze the security performance of the decoy-state BB84 QKD system under the optimal hidden pulse attack model that shows enormous performance degradation in terms of both secret key rate and transmission distance.

  17. Secure Data Aggregation in Wireless Sensor Network-Fujisaki Okamoto(FO) Authentication Scheme against Sybil Attack.

    PubMed

    Nirmal Raja, K; Maraline Beno, M

    2017-07-01

    In the wireless sensor network(WSN) security is a major issue. There are several network security schemes proposed in research. In the network, malicious nodes obstruct the performance of the network. The network can be vulnerable by Sybil attack. When a node illicitly assertions multiple identities or claims fake IDs, the WSN grieves from an attack named Sybil attack. This attack threatens wireless sensor network in data aggregation, synchronizing system, routing, fair resource allocation and misbehavior detection. Henceforth, the research is carried out to prevent the Sybil attack and increase the performance of the network. This paper presents the novel security mechanism and Fujisaki Okamoto algorithm and also application of the work. The Fujisaki-Okamoto (FO) algorithm is ID based cryptographic scheme and gives strong authentication against Sybil attack. By using Network simulator2 (NS2) the scheme is simulated. In this proposed scheme broadcasting key, time taken for different key sizes, energy consumption, Packet delivery ratio, Throughput were analyzed.

  18. Double-blind, placebo-controlled trial on the effect of piracetam on breath-holding spells.

    PubMed

    Sawires, Happy; Botrous, Osama

    2012-07-01

    Breath-holding spells (BHS) are apparently frightening events occurring in otherwise healthy children.The aim of this study was to evaluate the efficacy of piracetam in the treatment of breath-holding spells. Forty patients with BHS (who were classified into two groups)were involved in a double-blinded placebo-controlled prospective study. Piracetam was given to group A while group B received placebo. Patients were followed monthly for a total period of 4 months. The numbers of attacks/month before and monthly after treatment were documented, and the overall number of attacks/month after treatment was calculated in both groups. The median number of attacks/month before treatment in the two groups was 5.5 and 5,respectively, while after the first month of treatment, it was 2 and 5, respectively. The median overall number of attacks/month after treatment in both groups was 1 and 5, respectively.There was a significant decline of number of attacks after piracetam treatment compared to placebo (p value<0.001). There were no reported side effects of the piracetam throughout the study period. In conclusion, piracetam is a safe and effective drug for the treatment of breath-holding spells in children.

  19. Fast WEP-Key Recovery Attack Using Only Encrypted IP Packets

    NASA Astrophysics Data System (ADS)

    Teramura, Ryoichi; Asakura, Yasuo; Ohigashi, Toshihiro; Kuwakado, Hidenori; Morii, Masakatu

    Conventional efficient key recovery attacks against Wired Equivalent Privacy (WEP) require specific initialization vectors or specific packets. Since it takes much time to collect the packets sufficiently, any active attack should be performed. An Intrusion Detection System (IDS), however, will be able to prevent the attack. Since the attack logs are stored at the servers, it is possible to prevent such an attack. This paper proposes an algorithm for recovering a 104-bit WEP key from any IP packets in a realistic environment. This attack needs about 36, 500 packets with a success probability 0.5, and the complexity of our attack is equivalent to about 220 computations of the RC4 key setups. Since our attack is passive, it is difficult for both WEP users and administrators to detect our attack.

  20. Does the initiation of urate-lowering treatment during an acute gout attack prolong the current episode and precipitate recurrent attacks: a systematic literature review.

    PubMed

    Eminaga, Fatma; La-Crette, Jonathan; Jones, Adrian; Abhishek, A

    2016-12-01

    The aim of this study was to systematically review the literature on effect of initiating urate-lowering treatment (ULT) during an acute attack of gout on duration of index attack and persistence on ULT. OVID (Medline), EMBASE and AMED were searched to identify randomized controlled trials (RCTs) of ULT initiation during acute gout attack published in English language. Two reviewers appraised the study quality and extracted data independently. Standardized mean difference (SMD) and relative risk (RR) were used to pool continuous and categorical data. Meta-analysis was carried out using STATA version 14. A total of 537 studies were selected. A total of 487 titles and abstracts were reviewed after removing duplicates. Three RCTs were identified. There was evidence from two high-quality studies that early initiation of allopurinol did not increase pain severity at days 10-15 [SMD pooled (95 % CI) 0.18 (-0.58, 0.93)]. Data from three studies suggested that initiation of ULT during an acute attack of gout did not associate with dropouts [RR pooled (95 % CI) 1.16 (0.58, 2.31)]. There is moderate-quality evidence that the initiation of ULT during an acute attack of gout does not increase pain severity and risk of ULT discontinuation. Larger studies are required to confirm these findings so that patients with acute gout can be initiated on ULT with confidence.

  1. Migraine headache is present in the aura phase

    PubMed Central

    Hansen, Jakob M.; Lipton, Richard B.; Dodick, David W.; Silberstein, Stephen D.; Saper, Joel R.; Aurora, Sheena K.; Goadsby, Peter J.

    2012-01-01

    ABSTRACT Objectives: Migraine aura is commonly considered to be a distinct phase of a migraine attack that precedes headache. The objective of the study was to examine a large number of prospectively recorded attacks of migraine with aura and determine the timing of headache and other migraine symptoms relative to aura. Methods: As part of a clinical trial we collected prospective data on the time course of headache and other symptoms relative to the aura. Patients (n = 267) were enrolled from 16 centers, and asked to keep a headache diary for 1 month (phase I). They were asked to record headache symptoms as soon as possible after aura began and always within 1 hour of aura onset. A total of 456 attacks were reported during phase I by 201 patients. These patients were then randomized and included in phase II, during which a total of 405 attacks were reported in 164 patients. In total, we present data from 861 attacks of migraine with aura from 201 patients. Results: During the aura phase, the majority of attacks (73%) were associated with headache. Other migraine symptoms were also frequently reported during the aura: nausea (51%), photophobia (88%), and photophobia (73%). During the first 15 minutes within the onset of aura, 54% of patients reported headache fulfilling the criteria for migraine. Conclusion: Our results indicate that headaches as well as associated migraine symptoms are present early, during the aura phase of the migraine attack in the majority of patients. PMID:23115208

  2. Interpersonal coordination tendencies supporting the creation/prevention of goal scoring opportunities in futsal.

    PubMed

    Vilar, Luís; Araújo, Duarte; Davids, Keith; Travassos, Bruno; Duarte, Ricardo; Parreira, João

    2014-01-01

    Research on 1vs1 sub-phases in team sports has shown how one player coordinates his/her actions with his/her opponent and the location of a target/goal to attain performance objectives. In this study, we extended this approach to analysis of 5vs5 competitive performance in the team sport of futsal to provide a performance analysis framework that explains how players coordinate their actions to create/prevent opportunities to score goals. For this purpose, we recorded all 10 futsal matches of the 2009 Lusophony Games held in Lisbon. We analysed the displacement trajectories of a shooting attacker and marking defender in plays ending in a goal, a goalkeeper's save, and a defender's interception, at four specific moments during performance: (1) assisting attacker's ball reception and (2) moment of passing, (3) shooter's ball reception, and (4), shot on goal. Statistical analysis showed that when a goal was scored, the defender's angle to the goal and to the attacker tended to decrease, the attacker was able to move to the same distance to the goal alongside the defender, and the attacker was closer to the defender and moving at the same velocity (at least) as the defender. This study identified emergent patterns of coordination between attackers and defenders under key competitive task constraints, such as the location of the goal, which supported successful performance in futsal.

  3. Adaptive optimisation-offline cyber attack on remote state estimator

    NASA Astrophysics Data System (ADS)

    Huang, Xin; Dong, Jiuxiang

    2017-10-01

    Security issues of cyber-physical systems have received increasing attentions in recent years. In this paper, deception attacks on the remote state estimator equipped with the chi-squared failure detector are considered, and it is assumed that the attacker can monitor and modify all the sensor data. A novel adaptive optimisation-offline cyber attack strategy is proposed, where using the current and previous sensor data, the attack can yield the largest estimation error covariance while ensuring to be undetected by the chi-squared monitor. From the attacker's perspective, the attack is better than the existing linear deception attacks to degrade the system performance. Finally, some numerical examples are provided to demonstrate theoretical results.

  4. Rofecoxib versus ibuprofen for acute treatment of migraine: a randomised placebo controlled trial

    PubMed Central

    Misra, U; Jose, M; Kalita, J

    2004-01-01

    Background: Rofecoxib is a potent cyclo-oxygenase-2 inhibitor with a long duration of action. Its role in migraine has not been systematically evaluated. Aim: To study the efficacy of rofecoxib in migraine. Method: In a randomised placebo controlled trial rofecoxib 25 mg, ibuprofen 400 mg, and placebo were compared regarding their efficacy in relieving acute migraine attack. Migraine patients with 2–6 attacks per month were recruited. Headache severity, functional disability, and severity of associated symptoms were graded on a 0–3 scale. The primary endpoint was pain relief at two hours. Relief of associated symptoms and sustained pain relief for 24 hours were also noted. Result: One hundred and twenty four patients were randomised into rofecoxib (42), ibuprofen (40), and placebo (42) groups. One hundred and one patients were followed up: 33 on rofecoxib, 35 ibuprofen, and 33 placebo. Patients' ages ranged from 16–62 (mean 31.4) years, and 83 were females. Pain relief at two hours was noted in 45.5% on rofecoxib, 55.6% on ibuprofen, and 9.1% in the placebo group. The associated symptoms at two hours were reduced in 39.4% on rofecoxib, 50% on ibuprofen, and 9.1% in the placebo group. Sustained 24 hour pain relief was noted in 36.4% on rofecoxib, 41% on ibuprofen, and 6.1% in the placebo group. In the ibuprofen group, five patients had abdominal pain but there were no side effects in those on rofecoxib or in the control group. Both rofecoxib and ibuprofen were significantly effective in relieving pain, associated symptoms at two hours, and in sustained pain relief. There was no significant difference between rofecoxib and ibuprofen in aborting acute migraine attacks. Conclusions: Both ibuprofen and rofecoxib were superior to placebo in aborting an acute migraine attack, and there was no significant difference in their efficacy in an acute migraine attack. PMID:15579612

  5. Cost‐Effectiveness of Clopidogrel‐Aspirin Versus Aspirin Alone for Acute Transient Ischemic Attack and Minor Stroke

    PubMed Central

    Pan, Yuesong; Wang, Anxin; Liu, Gaifen; Zhao, Xingquan; Meng, Xia; Zhao, Kun; Liu, Liping; Wang, Chunxue; Johnston, S. Claiborne; Wang, Yilong; Wang, Yongjun

    2014-01-01

    Background Treatment with the combination of clopidogrel and aspirin taken soon after a transient ischemic attack (TIA) or minor stroke was shown to reduce the 90‐day risk of stroke in a large trial in China, but the cost‐effectiveness is unknown. This study sought to estimate the cost‐effectiveness of the clopidogrel‐aspirin regimen for acute TIA or minor stroke. Methods and Results A Markov model was created to determine the cost‐effectiveness of treatment of acute TIA or minor stroke patients with clopidogrel‐aspirin compared with aspirin alone. Inputs for the model were obtained from clinical trial data, claims databases, and the published literature. The main outcome measure was cost per quality‐adjusted life‐years (QALYs) gained. One‐way and multivariable probabilistic sensitivity analyses were performed to test the robustness of the findings. Compared with aspirin alone, clopidogrel‐aspirin resulted in a lifetime gain of 0.037 QALYs at an additional cost of CNY 1250 (US$ 192), yielding an incremental cost‐effectiveness ratio of CNY 33 800 (US$ 5200) per QALY gained. Probabilistic sensitivity analysis showed that clopidogrel‐aspirin therapy was more cost‐effective in 95.7% of the simulations at a willingness‐to‐pay threshold recommended by the World Health Organization of CNY 105 000 (US$ 16 200) per QALY. Conclusions Early 90‐day clopidogrel‐aspirin regimen for acute TIA or minor stroke is highly cost‐effective in China. Although clopidogrel is generic, Plavix is brand in China. If Plavix were generic, treatment with clopidogrel‐aspirin would have been cost saving. PMID:24904018

  6. All or nothing: Area-wide approach frustrates peachtree borers in Georgia

    USDA-ARS?s Scientific Manuscript database

    Mating disruption research has been done in the southeast against borers attacking peach since the sex pheromones of the peachtree borer, Synanthedon exitiosa (Lepidoptera: Sesiidae) and lesser peachtree borer, S. pictipes (Lepidoptera: Sesiidae) were identified. However, replicated trials over thr...

  7. Expanding the Playing Field: Immune-Based Therapy Shows Potential for Lung, Other Cancers

    Cancer.gov

    Results from two early-phase clinical trials presented at the 2012 American Society of Clinical Oncology annual meeting provide further evidence that priming the immune system to attack tumors has potential as a treatment for certain cancers.

  8. Situational awareness of a coordinated cyber attack

    NASA Astrophysics Data System (ADS)

    Sudit, Moises; Stotz, Adam; Holender, Michael

    2005-03-01

    As technology continues to advance, services and capabilities become computerized, and an ever increasing amount of business is conducted electronically the threat of cyber attacks gets compounded by the complexity of such attacks and the criticality of the information which must be secured. A new age of virtual warfare has dawned in which seconds can differentiate between the protection of vital information and/or services and a malicious attacker attaining their goal. In this paper we present a novel approach in the real-time detection of multistage coordinated cyber attacks and the promising initial testing results we have obtained. We introduce INFERD (INformation Fusion Engine for Real-time Decision-making), an adaptable information fusion engine which performs fusion at levels zero, one, and two to provide real-time situational assessment and its application to the cyber domain in the ECCARS (Event Correlation for Cyber Attack Recognition System) system. The advantages to our approach are fourfold: (1) The complexity of the attacks which we consider, (2) the level of abstraction in which the analyst interacts with the attack scenarios, (3) the speed at which the information fusion is presented and performed, and (4) our disregard for ad-hoc rules or a priori parameters.

  9. Countermeasure against blinding attacks on low-noise detectors with a background-noise-cancellation scheme

    NASA Astrophysics Data System (ADS)

    Lee, Min Soo; Park, Byung Kwon; Woo, Min Ki; Park, Chang Hoon; Kim, Yong-Su; Han, Sang-Wook; Moon, Sung

    2016-12-01

    We developed a countermeasure against blinding attacks on low-noise detectors with a background-noise-cancellation scheme in quantum key distribution (QKD) systems. Background-noise cancellation includes self-differencing and balanced avalanche photon diode (APD) schemes and is considered a promising solution for low-noise APDs, which are critical components in high-performance QKD systems. However, its vulnerability to blinding attacks has been recently reported. In this work, we propose a countermeasure that prevents this potential security loophole from being used in detector blinding attacks. An experimental QKD setup is implemented and various tests are conducted to verify the feasibility and performance of the proposed method. The obtained measurement results show that the proposed scheme successfully detects occurring blinding-attack-based hacking attempts.

  10. Machine Learning Methods for Attack Detection in the Smart Grid.

    PubMed

    Ozay, Mete; Esnaola, Inaki; Yarman Vural, Fatos Tunay; Kulkarni, Sanjeev R; Poor, H Vincent

    2016-08-01

    Attack detection problems in the smart grid are posed as statistical learning problems for different attack scenarios in which the measurements are observed in batch or online settings. In this approach, machine learning algorithms are used to classify measurements as being either secure or attacked. An attack detection framework is provided to exploit any available prior knowledge about the system and surmount constraints arising from the sparse structure of the problem in the proposed approach. Well-known batch and online learning algorithms (supervised and semisupervised) are employed with decision- and feature-level fusion to model the attack detection problem. The relationships between statistical and geometric properties of attack vectors employed in the attack scenarios and learning algorithms are analyzed to detect unobservable attacks using statistical learning methods. The proposed algorithms are examined on various IEEE test systems. Experimental analyses show that machine learning algorithms can detect attacks with performances higher than attack detection algorithms that employ state vector estimation methods in the proposed attack detection framework.

  11. Distinguishing attack and second-preimage attack on encrypted message authentication codes (EMAC)

    NASA Astrophysics Data System (ADS)

    Ariwibowo, Sigit; Windarta, Susila

    2016-02-01

    In this paper we show that distinguisher on CBC-MAC can be applied to Encrypted Message Authentication Code (EMAC) scheme. EMAC scheme in general is vulnerable to distinguishing attack and second preimage attack. Distinguishing attack simulation on AES-EMAC using 225 message modifications, no collision have been found. According to second preimage attack simulation on AES-EMAC no collision found between EMAC value of S1 and S2, i.e. no second preimage found for messages that have been tested. Based on distinguishing attack simulation on truncated AES-EMAC we found collision in every message therefore we cannot distinguish truncated AES-EMAC with random function. Second-preimage attack is successfully performed on truncated AES-EMAC.

  12. Effect of attack angle on flow characteristic of centrifugal fan

    NASA Astrophysics Data System (ADS)

    Wu, Y.; Dou, H. S.; Wei, Y. K.; Chen, X. P.; Chen, Y. N.; Cao, W. B.

    2016-05-01

    In this paper, numerical simulation is performed for the performance and internal flow of a centrifugal fan with different operating conditions using steady three-dimensional incompressible Navier-Stokes equations coupled with the RNG k-e turbulent model. The performance curves, the contours of static pressure, total pressure, radial velocity, relative streamlines and turbulence intensity at different attack angles are obtained. The distributions of static pressure and velocity on suction surface and pressure surface in the same impeller channel are compared for various attack angles. The research shows that the efficiency of the centrifugal fan is the highest when the attack angle is 8 degree. The main reason is that the vortex flow in the impeller is reduced, and the jet-wake pattern is weakened at the impeller outlet. The pressure difference between pressure side and suction side is smooth and the amplitude of the total pressure fluctuation is low along the circumferential direction. These phenomena may cause the loss reduced for the attack angle of about 8 degree.

  13. Ticagrelor for the treatment of atherosclerotic disease: insights from the PARTHENON clinical development program.

    PubMed

    Held, Peter; Himmelmann, Anders; Ditmarsch, Marc

    2016-07-01

    Ticagrelor (P2Y12 receptor antagonist) is presently indicated for preventing atherothrombotic events in patients with acute coronary syndrome and patients with a history of myocardial infarction. The PARTHENON clinical development program comprises five randomized, controlled, cardiovascular, indication-seeking outcome studies, aiming to evaluate ticagrelor across the spectrum of patients with atherothrombotic disease. Results of two large-scale trials support a benefit for ticagrelor in patients with acute coronary syndrome (PLATO; ClinicalTrials.gov: NCT00391872) and in patients with a history of myocardial infarction (PEGASUS-TIMI 54; ClinicalTrials.gov: NCT01225562). Ongoing trials will provide information on the efficacy and safety of ticagrelor in patients with acute ischemic stroke or transient ischemic attack (SOCRATES; ClinicalTrials.gov: NCT01994720), peripheral artery disease (EUCLID; ClinicalTrials.gov: NCT01732822) and coronary artery disease in patients with Type 2 diabetes mellitus (THEMIS: ClinicalTrials.gov: NCT01991795).

  14. Antiplatelet regimens in the long-term secondary prevention of transient ischaemic attack and ischaemic stroke: an updated network meta-analysis

    PubMed Central

    Niu, Peng-Peng; Guo, Zhen-Ni; Jin, Hang; Xing, Ying-Qi; Yang, Yi

    2016-01-01

    Objective To examine the comparative efficacy and safety of different antiplatelet regimens in patients with prior non-cardioembolic ischaemic stroke or transient ischaemic attack. Design Systematic review and network meta-analysis. Data sources As on 31 March 2015, all randomised controlled trials that investigated the effects of antiplatelet agents in the long-term (≥3 months) secondary prevention of non-cardioembolic transient ischaemic attack or ischaemic stroke were searched and identified. Outcome measures The primary outcome measure of efficacy was serious vascular events (non-fatal stroke, non-fatal myocardial infarction and vascular death). The outcome measure of safety was any bleeding. Results A total of 36 randomised controlled trials (82 144 patients) were included. Network meta-analysis showed that cilostazol was significantly more effective than clopidogrel (OR 0.77, 95% credible interval 0.60–0.98) and low-dose (75–162 mg daily) aspirin (0.69, 0.55–0.86) in the prevention of serious vascular events. Aspirin (50 mg daily) plus dipyridamole (400 mg daily) and clopidogrel reduced the risk of serious vascular events compared with low-dose aspirin; however, the difference was not statistically significant. Furthermore, low-dose aspirin was as effective as higher daily doses. Cilostazol was associated with a significantly lower bleeding risk than most of the other regimens. Moreover, aspirin plus clopidogrel was associated with significantly more haemorrhagic events than other regimens. Direct comparisons showed similar results as the network meta-analysis. Conclusions Cilostazol was significantly more effective than aspirin and clopidogrel alone in the long-term prevention of serious vascular events in patients with prior non-cardioembolic ischaemic stroke or transient ischaemic attack. Cilostazol was associated with a significantly lower bleeding risk than low-dose aspirin (75–162 mg daily) and aspirin (50 mg daily) plus dipyridamole (400 mg daily). Low-dose aspirin was as effective as higher daily doses. However, further large, randomised, controlled, head-to-head trials are needed, especially in non-Asian ethnic groups. PMID:26988347

  15. The efficacy of trimetazidine on stable angina pectoris: a meta-analysis of randomized clinical trials.

    PubMed

    Peng, Song; Zhao, Min; Wan, Jing; Fang, Qi; Fang, Dong; Li, Kaiyong

    2014-12-20

    This meta-analysis aimed to evaluate the efficacy of trimetazidine in combination with other anti-anginal drugs versus other anti-anginal drugs in the treatment of stable angina pectoris (SAP). Randomized controlled trials (RCTs) published in English and Chinese were retrieved from computerized databases: Embase, PubMed, and CNKI. Primary outcomes consist of clinical parameters (numbers of weekly angina attacks and nitroglycerin use) and ergometric parameters (time to 1mm ST-segment depression, and total work (in Mets) and exercise duration (in seconds) at peak exercise) in stable angina pectoris treated by trimetazidine or not. The quality of studies was evaluated using Jadad score. Data analysis of 13 studies was performed using Stata 12.0 software. Results showed that treatment of trimetazidine and other anti-anginal drugs was associated with a smaller weekly mean number of angina attacks (WMD=-0.95, 95%CI: -1.30 to -0.61, Z=5.39, P<0.001), fewer weekly nitroglycerin use (WMD=-0.98, 95%CI: -1.44 to -0.52, Z=4.19, P<0.001), longer time to 1mm ST-segment depression (WMD=0.30, 95%CI: 0.17 to 0.43, Z=4.46, P<0.001), higher total work (WMD=0.82, 95%CI: 0.44 to 1.20, Z=4.22, P<0.001) and longer exercise duration at peak exercise (WMD=49.81, 95%CI: 15.04 to 84.57, Z=6.38, P<0.001) than treatment of other anti-anginal drugs for stable angina pectoris. Sensitivity analysis was performed. Sub-group analysis showed that treatment duration was not a significant moderator and patients treated within 8 weeks and above 12 weeks had no difference in the outcomes addressed in this meta-analysis. No publish bias was detected. This meta-analysis confirms the efficacy of trimetazidine in the treatment of stable angina pectoris, in comparison with conventional antianginal agents, regardless of treatment duration. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  16. Clopidogrel With Aspirin in Acute Minor Stroke or Transient Ischemic Attack (CHANCE) Trial: One-Year Outcomes.

    PubMed

    Wang, Yilong; Pan, Yuesong; Zhao, Xingquan; Li, Hao; Wang, David; Johnston, S Claiborne; Liu, Liping; Meng, Xia; Wang, Anxin; Wang, Chunxue; Wang, Yongjun

    2015-07-07

    The Clopidogrel in High-risk patients with Acute Non-disabling Cerebrovascular Events (CHANCE) trial showed that the combined treatment of clopidogrel and aspirin decreases the 90-day risk of stroke without increasing hemorrhage in comparison with aspirin alone, but provided insufficient data to establish whether the benefit persisted over a longer period of time beyond the trial termination. We report the 1-year follow-up outcomes of this trial. The trial was a randomized, double-blind, placebo-controlled trial conducted at 114 centers in China. We randomly assigned 5170 patients within 24 hours after onset of minor stroke or high-risk transient ischemic attack to clopidogrel-aspirin therapy (loading dose of 300 mg of clopidogrel on day 1, followed by 75 mg of clopidogrel per day for 90 days, plus 75 mg of aspirin per day for the first 21 days) or to the aspirin-alone group (75 mg/d for 90 days). The primary outcome was stroke event (ischemic or hemorrhagic) during 1-year follow-up. Differences in outcomes between groups were assessed by using the Cox proportional hazards model. Stroke occurred in 275 (10.6%) patients in the clopidogrel-aspirin group, in comparison with 362 (14.0%) patients in the aspirin group (hazard ratio, 0.78; 95% confidence interval, 0.65-0.93; P=0.006). Moderate or severe hemorrhage occurred in 7 (0.3%) patients in the clopidogrel-aspirin group and in 9 (0.4%) patients in the aspirin group (P=0.44). The early benefit of clopidogrel-aspirin treatment in reducing the risk of subsequent stroke persisted for the duration of 1-year of follow-up. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00979589. © 2015 American Heart Association, Inc.

  17. Study design of the CLOSURE I Trial: a prospective, multicenter, randomized, controlled trial to evaluate the safety and efficacy of the STARFlex septal closure system versus best medical therapy in patients with stroke or transient ischemic attack due to presumed paradoxical embolism through a patent foramen ovale.

    PubMed

    Furlan, Anthony J; Reisman, Mark; Massaro, Joseph; Mauri, Laura; Adams, Harold; Albers, Gregory W; Felberg, Robert; Herrmann, Howard; Kar, Saibal; Landzberg, Michael; Raizner, Albert; Wechsler, Lawrence

    2010-12-01

    Some strokes of unknown etiology may be the result of a paradoxical embolism traversing through a nonfused foramen ovale (patent foramen ovale [PFO]). The utility of percutaneously placed devices for treatment of patients with cryptogenic stroke or transient ischemic attack (TIA) and PFO is unknown. In addition, there are no clear data about the utility of medical interventions or other surgical procedures in this situation. Despite limited data, many patients are being treated with PFO closure devices. Thus, there is a strong need for clinical trials that test the potential efficacy of PFO occlusive devices in this situation. To address this gap in medical knowledge, we designed the CLOSURE I trial, a randomized, clinical trial comparing the use of a percutaneously placed PFO occlusive device and best medical therapy versus best medical therapy alone for prevention of recurrent ischemic neurologic symptoms among persons with TIA or ischemic stroke. This prospective, multicenter, randomized, controlled trial has finished enrollment. Two-year follow-up for all 910 patients is required. The primary end point is the 2-year incidence of stroke or TIA, all-cause mortality for the first 30 days, and neurologic mortality from ≥ 31 days of follow-up, as adjudicated by a panel of physicians who are unaware of treatment allocation. This article describes the rationale and study design of CLOSURE I. This trial should provide information as to whether the STARFlex septal closure system is safe and more effective than best medical therapy alone in preventing recurrent stroke/TIA and mortality in patients with PFO and whether the STARFlex septal closure device can demonstrate superiority compared with best medical therapy alone. Clinical Trial Registration-URL: http://www.clinicaltrials.gov. Unique identifier: NCT00201461.

  18. Ticagrelor in Acute Stroke or Transient Ischemic Attack in Asian Patients: From the SOCRATES Trial (Acute Stroke or Transient Ischemic Attack Treated With Aspirin or Ticagrelor and Patient Outcomes).

    PubMed

    Wang, Yongjun; Minematsu, Kazuo; Wong, Ka Sing Lawrence; Amarenco, Pierre; Albers, Gregory W; Denison, Hans; Easton, J Donald; Evans, Scott R; Held, Peter; Jonasson, Jenny; Molina, Carlos A; Johnston, S Claiborne

    2017-01-01

    In the SOCRATES trial (Acute Stroke or Transient Ischemic Attack Treated With Aspirin or Ticagrelor and Patient Outcomes), ticagrelor was not superior to aspirin. Because of differences in patient demographics and stroke disease pattern in Asia, outcomes of ticagrelor versus aspirin were assessed among Asian patients in a prespecified exploratory analysis. Baseline demographics, treatment effects, and safety of ticagrelor and aspirin were assessed among Asian patients. Differences in outcomes between groups were assessed using Cox proportional hazard model. A total of 3858 (29.2%) SOCRATES participants were recruited in Asia. Among the Asian patients, the primary end point event occurred in 186 (9.6%) of the 1933 patients treated with ticagrelor, versus 224 (11.6%) of the 1925 patients treated with aspirin (hazard ratio, 0.81; 95% confidence interval, 0.67-0.99). The exploratory P value for treatment-by-region interaction was 0.27. The primary end point event rate in the Asian subgroup was numerically higher than that in the non-Asian group (10.6% versus 5.7%; nominal P<0.01). Among the Asian patients, the rate of PLATO (Platelet Inhibition and Patient Outcomes)-defined major bleeding was similar in the ticagrelor group and the aspirin group (0.6% versus 0.8%; hazard ratio, 0.76; 95% confidence interval, 0.36-1.61). The event rates were numerically higher in the Asian patients. Among the Asian patients with acute stroke or transient ischemic attacks, there was a trend toward a lower hazard ratio in reducing risk of the primary end point of stroke, myocardial infarction, or death in the ticagrelor group. URL: http://www.clinicaltrials.gov. Unique identifier: NCT01994720. © 2016 American Heart Association, Inc.

  19. Injury rates during the 1988 US Olympic Team Trials for taekwondo.

    PubMed Central

    Zemper, E D; Pieter, W

    1989-01-01

    Injury rates were recorded during the 1988 US Olympic Team Trials for taekwondo involving 48 men and 48 women. The injury rate for men (12.74/100 athlete-exposures) was about 40 per cent higher than the rate for women (9.01/100 athlete-exposures). The foot and the head were the most frequently injured body parts. Contusions were the predominant type of injury, and concussions were recorded for both men and women. A large proportion (41 per cent) of the men's injuries were the result of receiving a blow from an unblocked attack. For the women the most common injury situation (40 per cent) was while attacking with a kick. For both men and women, 15 per cent of the reported injuries were time-loss injuries. The head injuries found in this study are discussed with reference to the high impact velocities and momentum levels generated during taekwondo kicking. Recommendations are made with regard to protective equipment testing and rule changes to reduce the possibility of cerebral injury. PMID:2620229

  20. Testbed-based Performance Evaluation of Attack Resilient Control for AGC

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ashok, Aditya; Sridhar, Siddharth; McKinnon, Archibald D.

    The modern electric power grid is a complex cyber-physical system whose reliable operation is enabled by a wide-area monitoring and control infrastructure. This infrastructure, supported by an extensive communication backbone, enables several control applications functioning at multiple time scales to ensure the grid is maintained within stable operating limits. Recent events have shown that vulnerabilities in this infrastructure may be exploited to manipulate the data being exchanged. Such a scenario could cause the associated control application to mis-operate, potentially causing system-wide instabilities. There is a growing emphasis on looking beyond traditional cybersecurity solutions to mitigate such threats. In this papermore » we perform a testbed-based validation of one such solution - Attack Resilient Control (ARC) - on Iowa State University's \\textit{PowerCyber} testbed. ARC is a cyber-physical security solution that combines domain-specific anomaly detection and model-based mitigation to detect stealthy attacks on Automatic Generation Control (AGC). In this paper, we first describe the implementation architecture of the experiment on the testbed. Next, we demonstrate the capability of stealthy attack templates to cause forced under-frequency load shedding in a 3-area test system. We then validate the performance of ARC by measuring its ability to detect and mitigate these attacks. Our results reveal that ARC is efficient in detecting stealthy attacks and enables AGC to maintain system operating frequency close to its nominal value during an attack. Our studies also highlight the importance of testbed-based experimentation for evaluating the performance of cyber-physical security and control applications.« less

  1. Study protocol of Prednisone in episodic Cluster Headache (PredCH): a randomized, double-blind, placebo-controlled parallel group trial to evaluate the efficacy and safety of oral prednisone as an add-on therapy in the prophylactic treatment of episodic cluster headache with verapamil

    PubMed Central

    2013-01-01

    Background Episodic cluster headache (ECH) is a primary headache disorder that severely impairs patient’s quality of life. First-line therapy in the initiation of a prophylactic treatment is verapamil. Due to its delayed onset of efficacy and the necessary slow titration of dosage for tolerability reasons prednisone is frequently added by clinicians to the initial prophylactic treatment of a cluster episode. This treatment strategy is thought to effectively reduce the number and intensity of cluster attacks in the beginning of a cluster episode (before verapamil is effective). This study will assess the efficacy and safety of oral prednisone as an add-on therapy to verapamil and compare it to a monotherapy with verapamil in the initial prophylactic treatment of a cluster episode. Methods and design PredCH is a prospective, randomized, double-blind, placebo-controlled trial with parallel study arms. Eligible patients with episodic cluster headache will be randomized to a treatment intervention with prednisone or a placebo arm. The multi-center trial will be conducted in eight German headache clinics that specialize in the treatment of ECH. Discussion PredCH is designed to assess whether oral prednisone added to first-line agent verapamil helps reduce the number and intensity of cluster attacks in the beginning of a cluster episode as compared to monotherapy with verapamil. Trial registration German Clinical Trials Register DRKS00004716 PMID:23889923

  2. Interleukin-5 Inhibitors for Severe Asthma: Rationale and Future Outlook.

    PubMed

    Shrimanker, Rahul; Pavord, Ian D

    2017-04-01

    In this review, we outline the pathophysiology of severe asthma and discuss the role of anti-interleukin (IL)-5 inhibitors for the treatment of asthma. Anti-IL-5 treatments have shown efficacy in reducing the rate of severe asthma attacks in eosinophilic asthma. We review the history of the development of these agents, lessons learnt about severe asthma along the way and key clinical trials supporting efficacy of the three anti-IL-5 treatments that are clinically available or undergoing clinical trials in asthma.

  3. [Prophylactic drug treatment of migraine].

    PubMed

    Massiou, H; Bousser, M-G

    2005-07-01

    Prophylactic treatment is mainly intended to reduce the frequency of migraine attacks. Based on the results of published controlled trials, the main prophylactic drugs are some beta-blockers, methysergide, pizotifene, oxetorone, flunarizine, amitriptyline, NSAIDs, sodium valproate and topiramate. With these drugs, the frequency of attacks can be reduced by half in 50 percent of patients. Some less evaluated substances such as aspirin, DHE, indoramine, and angiotensin II inhibitors may be useful. The decision to treat with drugs and the choice of a prophylactic drug are made together with the patient. The superiority of one major drug over another has never been demonstrated in a comparative trial, thus the choice of the drug to start with depends on the possible side effects and contraindications, the characteristics of the migraine attacks, and the associated morbidities and possible interactions with abortive medications. Doses should be increased gradually, in order to reach the recommended daily dose, only if tolerance permits. Treatment efficacy has to be assessed after 2 or 3 months, and in case of failure or poor tolerance, another treatment should be started. If the treatment is successful, it should be continued for 6 to 12 months, and then tapered off. The moderate efficacy and the frequency of the side effects observed with prophylactic drugs explain the high rate of withdrawals. Some patients nevertheless dramatically improve, warranting trying several drugs successively in order to find the most appropriate one.

  4. A qualitative study exploring patients' experiences of standard care or cardiac rehabilitation post minor stroke and transient ischaemic attack.

    PubMed

    Hillsdon, Kaye M; Kersten, Paula; Kirk, Hayden J S

    2013-09-01

    To explore individuals' experiences of receiving either standard care or comprehensive cardiac rehabilitation post minor stroke or transient ischaemic attack. A qualitative study using semi-structured interviews, alongside a randomized controlled trial, exploring the effectiveness of comprehensive cardiac rehabilitation compared with standard care. Interviews were transcribed verbatim and subjected to thematic analysis. Individuals' homes. People who have experienced a minor stroke or transient ischaemic attack and who were partaking in a secondary prevention randomized controlled trial (6-7 months post the event, 17 males, five females; mean age 67 years). Not relevant. Not relevant. Four themes were identified: information delivery, comparing oneself with others, psychological impact, attitudes and actions regarding risk factor reduction. Participants indicated a need for improved information delivery, specific to their own risk factors and lifestyle changes. Many experienced psychological impact as a result of their minor stroke. Participants were found to make two types of social comparison; the comparison of self to another affected by stroke, and the comparison of self to cardiac patients. Comprehensive cardiac rehabilitation was reported to have positive effects on people's motivation to exercise. Following a minor stroke, many individuals do not recall information given or risk factors specific to them. Downward comparison with individuals who have had a cardiovascular event led to some underplaying the significance of their minor stroke.

  5. Defense of Cyber Infrastructures Against Cyber-Physical Attacks Using Game-Theoretic Models

    DOE PAGES

    Rao, Nageswara S. V.; Poole, Stephen W.; Ma, Chris Y. T.; ...

    2015-04-06

    The operation of cyber infrastructures relies on both cyber and physical components, which are subject to incidental and intentional degradations of different kinds. Within the context of network and computing infrastructures, we study the strategic interactions between an attacker and a defender using game-theoretic models that take into account both cyber and physical components. The attacker and defender optimize their individual utilities expressed as sums of cost and system terms. First, we consider a Boolean attack-defense model, wherein the cyber and physical sub-infrastructures may be attacked and reinforced as individual units. Second, we consider a component attack-defense model wherein theirmore » components may be attacked and defended, and the infrastructure requires minimum numbers of both to function. We show that the Nash equilibrium under uniform costs in both cases is computable in polynomial time, and it provides high-level deterministic conditions for the infrastructure survival. When probabilities of successful attack and defense, and of incidental failures are incorporated into the models, the results favor the attacker but otherwise remain qualitatively similar. This approach has been motivated and validated by our experiences with UltraScience Net infrastructure, which was built to support high-performance network experiments. In conclusion, the analytical results, however, are more general, and we apply them to simplified models of cloud and high-performance computing infrastructures.« less

  6. Defense of Cyber Infrastructures Against Cyber-Physical Attacks Using Game-Theoretic Models

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rao, Nageswara S. V.; Poole, Stephen W.; Ma, Chris Y. T.

    The operation of cyber infrastructures relies on both cyber and physical components, which are subject to incidental and intentional degradations of different kinds. Within the context of network and computing infrastructures, we study the strategic interactions between an attacker and a defender using game-theoretic models that take into account both cyber and physical components. The attacker and defender optimize their individual utilities expressed as sums of cost and system terms. First, we consider a Boolean attack-defense model, wherein the cyber and physical sub-infrastructures may be attacked and reinforced as individual units. Second, we consider a component attack-defense model wherein theirmore » components may be attacked and defended, and the infrastructure requires minimum numbers of both to function. We show that the Nash equilibrium under uniform costs in both cases is computable in polynomial time, and it provides high-level deterministic conditions for the infrastructure survival. When probabilities of successful attack and defense, and of incidental failures are incorporated into the models, the results favor the attacker but otherwise remain qualitatively similar. This approach has been motivated and validated by our experiences with UltraScience Net infrastructure, which was built to support high-performance network experiments. In conclusion, the analytical results, however, are more general, and we apply them to simplified models of cloud and high-performance computing infrastructures.« less

  7. Defense of Cyber Infrastructures Against Cyber-Physical Attacks Using Game-Theoretic Models.

    PubMed

    Rao, Nageswara S V; Poole, Stephen W; Ma, Chris Y T; He, Fei; Zhuang, Jun; Yau, David K Y

    2016-04-01

    The operation of cyber infrastructures relies on both cyber and physical components, which are subject to incidental and intentional degradations of different kinds. Within the context of network and computing infrastructures, we study the strategic interactions between an attacker and a defender using game-theoretic models that take into account both cyber and physical components. The attacker and defender optimize their individual utilities, expressed as sums of cost and system terms. First, we consider a Boolean attack-defense model, wherein the cyber and physical subinfrastructures may be attacked and reinforced as individual units. Second, we consider a component attack-defense model wherein their components may be attacked and defended, and the infrastructure requires minimum numbers of both to function. We show that the Nash equilibrium under uniform costs in both cases is computable in polynomial time, and it provides high-level deterministic conditions for the infrastructure survival. When probabilities of successful attack and defense, and of incidental failures, are incorporated into the models, the results favor the attacker but otherwise remain qualitatively similar. This approach has been motivated and validated by our experiences with UltraScience Net infrastructure, which was built to support high-performance network experiments. The analytical results, however, are more general, and we apply them to simplified models of cloud and high-performance computing infrastructures. © 2015 Society for Risk Analysis.

  8. Acupuncture as prophylaxis for menstrual-related migraine: study protocol for a multicenter randomized controlled trial

    PubMed Central

    2013-01-01

    Background Menstrual-related migraine is a common form of migraine affecting >50% of female migraineurs. Acupuncture may be a choice for menstrual-related migraine, when pharmacological prophylaxis is not suitable. However, the efficacy of acupuncture has not been confirmed. We design and perform a randomized controlled clinical trial to evaluate the efficacy of acupuncture compared with naproxen in menstrual-related migraine patients. Methods/Design This is a multicenter, single blind, randomized controlled clinical trial. A total of 184 participants will be randomly assigned to two different groups. Participants will receive verum acupuncture and placebo medicine in the treatment group, while participants in the control group will be treated with sham acupuncture and medicine (Naproxen Sustained Release Tablets). All treatments will be given for 3 months (menstrual cycles). The primary outcome measures are the change of migraine days inside the menstrual cycle and the proportion of responders (defined as the proportion of patients with at least a 50% reduction in the number of menstrual migraine days). The secondary outcome measures are the change of migraine days outside the menstrual cycle, duration of migraine attack, the Visual Analogue Scale (VAS), and intake of acute medication. The assessment will be made at baseline (before treatment), 3 months (menstrual cycles), and 4 months (menstrual cycles) after the first acupuncture session. Discussion The results of this trial will be helpful to supply the efficacy of acupuncture for menstrual-related migraine prophylaxis. Trial registration ISRCTN: ISRCTN57133712 PMID:24195839

  9. Evaluation of High-Angle-of-Attack Handling Qualities for the X-31A Using Standard Evaluation Maneuvers

    NASA Technical Reports Server (NTRS)

    Stoliker, Patrick C.; Bosworth, John T.

    1996-01-01

    The X-31A aircraft gross-acquisition and fine-tracking handling qualities have been evaluated using standard evaluation maneuvers developed by Wright Laboratory, Wright-Patterson Air Force Base. The emphasis of the testing is in the angle-of-attack range between 30 deg and 70 deg. Longitudinal gross-acquisition handling qualities results show borderline Level 1/Level 2 performance. Lateral gross-acquisition testing results in Level 1/Level 2 ratings below 45 deg angle of attack, degrading into Level 3 as angle of attack increases. The fine-tracking performance in both longitudinal and lateral axes also receives Level 1 ratings near 30 deg angle of attack, with the ratings tending towards Level 3 at angles of attack greater than 50 deg. These ratings do not match the expectations from the extensive close-in combat testing where the X-31A aircraft demonstrated fair to good handling qualities maneuvering for high angles of attack. This paper presents the results of the high-angle-of-attack handling qualities flight testing of the X-31A aircraft. Discussion of the preparation for the maneuvers, the pilot ratings, and selected pilot comments are included. Evaluation of the results is made in conjunction with existing Neal-Smith, bandwidth, Smith-Geddes, and military specifications.

  10. Evaluation of High-Angle-of-Attack Handling Qualities for the X-31A Using Standard Evaluation Maneuvers

    NASA Technical Reports Server (NTRS)

    Stoliker, Patrick C.; Bosworth, John T.

    1997-01-01

    The X-31A aircraft gross-acquisition and fine-tracking handling qualities have been evaluated using standard evaluation maneuvers developed by Wright Laboratory, Wright Patterson Air Force Base. The emphasis of the testing is in the angle-of-attack range between 30 deg. and 70 deg. Longitudinal gross-acquisition handling qualities results show borderline Level l/Level 2 performance. Lateral gross-acquisition testing results in Level l/Level 2 ratings below 45 deg. angle of attack, degrading into Level 3 as angle of attack increases. The fine tracking performance in both longitudinal and lateral axes also receives Level 1 ratings near 30 deg. angle of attack, with the ratings tending towards Level 3 at angles of attack greater than 50 deg. These ratings do not match the expectations from the extensive close-in combat testing where the X-31A aircraft demonstrated fair to good handling qualities maneuvering for high angles of attack. This paper presents the results of the high-angle-of-attack handling qualities flight testing of the X-31A aircraft. Discussion of the preparation for the maneuvers, the pilot ratings, and selected pilot comments are included. Evaluation of the results is made in conjunction with existing Neal Smith, bandwidth, Smith-Geddes, and military specifications.

  11. Enhancing Electromagnetic Side-Channel Analysis in an Operational Environment

    NASA Astrophysics Data System (ADS)

    Montminy, David P.

    Side-channel attacks exploit the unintentional emissions from cryptographic devices to determine the secret encryption key. This research identifies methods to make attacks demonstrated in an academic environment more operationally relevant. Algebraic cryptanalysis is used to reconcile redundant information extracted from side-channel attacks on the AES key schedule. A novel thresholding technique is used to select key byte guesses for a satisfiability solver resulting in a 97.5% success rate despite failing for 100% of attacks using standard methods. Two techniques are developed to compensate for differences in emissions from training and test devices dramatically improving the effectiveness of cross device template attacks. Mean and variance normalization improves same part number attack success rates from 65.1% to 100%, and increases the number of locations an attack can be performed by 226%. When normalization is combined with a novel technique to identify and filter signals in collected traces not related to the encryption operation, the number of traces required to perform a successful attack is reduced by 85.8% on average. Finally, software-defined radios are shown to be an effective low-cost method for collecting side-channel emissions in real-time, eliminating the need to modify or profile the target encryption device to gain precise timing information.

  12. Photon-number-splitting versus cloning attacks in practical implementations of the Bennett-Brassard 1984 protocol for quantum cryptography

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Niederberger, Armand; Scarani, Valerio; Gisin, Nicolas

    2005-04-01

    In practical quantum cryptography, the source sometimes produces multiphoton pulses, thus enabling the eavesdropper Eve to perform the powerful photon-number-splitting (PNS) attack. Recently, it was shown by Curty and Luetkenhaus [Phys. Rev. A 69, 042321 (2004)] that the PNS attack is not always the optimal attack when two photons are present: if errors are present in the correlations Alice-Bob and if Eve cannot modify Bob's detection efficiency, Eve gains a larger amount of information using another attack based on a 2{yields}3 cloning machine. In this work, we extend this analysis to all distances Alice-Bob. We identify a new incoherent 2{yields}3more » cloning attack which performs better than those described before. Using it, we confirm that, in the presence of errors, Eve's better strategy uses 2{yields}3 cloning attacks instead of the PNS. However, this improvement is very small for the implementations of the Bennett-Brassard 1984 (BB84) protocol. Thus, the existence of these new attacks is conceptually interesting but basically does not change the value of the security parameters of BB84. The main results are valid both for Poissonian and sub-Poissonian sources.« less

  13. Panic attack history and anxiety sensitivity in relation to cognitive-based smoking processes among treatment-seeking daily smokers.

    PubMed

    Johnson, Kirsten A; Farris, Samantha G; Schmidt, Norman B; Smits, Jasper A J; Zvolensky, Michael J

    2013-01-01

    Empirical research has found that panic attacks are related to increased risk of more severe nicotine withdrawal and poor cessation outcome. Anxiety sensitivity (AS; fear of anxiety and related sensations) has similarly been found to be related to an increased risk of acute nicotine withdrawal and poorer cessation outcome. However, research has yet to examine the relative contributions of panic attacks and AS in terms of cognitive-based smoking processes (e.g., negative reinforcement smoking expectancies, addictive and negative affect-based reduction smoking motives, barriers to cessation, problem symptoms experienced while quitting). Participants (n = 242; 57.4% male; M (age) = 38.1) were daily smokers recruited as a part of a larger randomized control trial for smoking cessation. It was hypothesized that both panic attacks and AS would uniquely and independently predict the studied cognitive-based smoking processes. As hypothesized, AS was uniquely and positively associated with all smoking processes after controlling for average number of cigarettes smoked per day, current Axis I diagnosis, and participant sex. However, panic attack history was only significantly related to problem symptoms experienced while quitting smoking. Although past research has demonstrated significant associations between panic attacks and certain aspects of cigarette smoking (e.g., severity of nicotine withdrawal; lower abstinence rates, and negative affect reduction motives), the present findings suggest that AS may be more relevant to understanding beliefs about and motives for smoking behavior as well as perceptions of cessation-related difficulties.

  14. Development, Validation, and Assessment of an Ischemic Stroke or Transient Ischemic Attack-Specific Prediction Tool for Obstructive Sleep Apnea.

    PubMed

    Sico, Jason J; Yaggi, H Klar; Ofner, Susan; Concato, John; Austin, Charles; Ferguson, Jared; Qin, Li; Tobias, Lauren; Taylor, Stanley; Vaz Fragoso, Carlos A; McLain, Vincent; Williams, Linda S; Bravata, Dawn M

    2017-08-01

    Screening instruments for obstructive sleep apnea (OSA), as used routinely to guide clinicians regarding patient referral for polysomnography (PSG), rely heavily on symptomatology. We sought to develop and validate a cerebrovascular disease-specific OSA prediction model less reliant on symptomatology, and to compare its performance with commonly used screening instruments within a population with ischemic stroke or transient ischemic attack (TIA). Using data on demographic factors, anthropometric measurements, medical history, stroke severity, sleep questionnaires, and PSG from 2 independently derived, multisite, randomized trials that enrolled patients with stroke or TIA, we developed and validated a model to predict the presence of OSA (i.e., Apnea-Hypopnea Index ≥5 events per hour). Model performance was compared with that of the Berlin Questionnaire, Epworth Sleepiness Scale (ESS), the Snoring, Tiredness, Observed apnea, high blood Pressure, Body mass index, Age, Neck circumference, and Gender instrument, and the Sleep Apnea Clinical Score. The new SLEEP Inventory (Sex, Left heart failure, ESS, Enlarged neck, weight [in Pounds], Insulin resistance/diabetes, and National Institutes of Health Stroke Scale) performed modestly better than other instruments in identifying patients with OSA, showing reasonable discrimination in the development (c-statistic .732) and validation (c-statistic .731) study populations, and having the highest negative predictive value of all in struments. Clinicians should be aware of these limitations in OSA screening instruments when making decisions about referral for PSG. The high negative predictive value of the SLEEP INventory may be useful in determining and prioritizing patients with stroke or TIA least in need of overnight PSG. Published by Elsevier Inc.

  15. Performance Evaluation of Localization Accuracy for a Log-Normal Shadow Fading Wireless Sensor Network under Physical Barrier Attacks

    PubMed Central

    Abdulqader Hussein, Ahmed; Rahman, Tharek A.; Leow, Chee Yen

    2015-01-01

    Localization is an apparent aspect of a wireless sensor network, which is the focus of much interesting research. One of the severe conditions that needs to be taken into consideration is localizing a mobile target through a dispersed sensor network in the presence of physical barrier attacks. These attacks confuse the localization process and cause location estimation errors. Range-based methods, like the received signal strength indication (RSSI), face the major influence of this kind of attack. This paper proposes a solution based on a combination of multi-frequency multi-power localization (C-MFMPL) and step function multi-frequency multi-power localization (SF-MFMPL), including the fingerprint matching technique and lateration, to provide a robust and accurate localization technique. In addition, this paper proposes a grid coloring algorithm to detect the signal hole map in the network, which refers to the attack-prone regions, in order to carry out corrective actions. The simulation results show the enhancement and robustness of RSS localization performance in the face of log normal shadow fading effects, besides the presence of physical barrier attacks, through detecting, filtering and eliminating the effect of these attacks. PMID:26690159

  16. Performance Evaluation of Localization Accuracy for a Log-Normal Shadow Fading Wireless Sensor Network under Physical Barrier Attacks.

    PubMed

    Hussein, Ahmed Abdulqader; Rahman, Tharek A; Leow, Chee Yen

    2015-12-04

    Localization is an apparent aspect of a wireless sensor network, which is the focus of much interesting research. One of the severe conditions that needs to be taken into consideration is localizing a mobile target through a dispersed sensor network in the presence of physical barrier attacks. These attacks confuse the localization process and cause location estimation errors. Range-based methods, like the received signal strength indication (RSSI), face the major influence of this kind of attack. This paper proposes a solution based on a combination of multi-frequency multi-power localization (C-MFMPL) and step function multi-frequency multi-power localization (SF-MFMPL), including the fingerprint matching technique and lateration, to provide a robust and accurate localization technique. In addition, this paper proposes a grid coloring algorithm to detect the signal hole map in the network, which refers to the attack-prone regions, in order to carry out corrective actions. The simulation results show the enhancement and robustness of RSS localization performance in the face of log normal shadow fading effects, besides the presence of physical barrier attacks, through detecting, filtering and eliminating the effect of these attacks.

  17. X-31 high angle of attack control system performance

    NASA Technical Reports Server (NTRS)

    Huber, Peter; Seamount, Patricia

    1994-01-01

    The design goals for the X-31 flight control system were: (1) level 1 handling qualities during post-stall maneuvering (30 to 70 degrees angle-of-attack); (2) thrust vectoring to enhance performance across the flight envelope; and (3) adequate pitch-down authority at high angle-of-attack. Additional performance goals are discussed. A description of the flight control system is presented, highlighting flight control system features in the pitch and roll axes and X-31 thrust vectoring characteristics. The high angle-of-attack envelope clearance approach will be described, including a brief explanation of analysis techniques and tools. Also, problems encountered during envelope expansion will be discussed. This presentation emphasizes control system solutions to problems encountered in envelope expansion. An essentially 'care free' envelope was cleared for the close-in-combat demonstrator phase. High angle-of-attack flying qualities maneuvers are currently being flown and evaluated. These results are compared with pilot opinions expressed during the close-in-combat program and with results obtained from the F-18 HARV for identical maneuvers. The status and preliminary results of these tests are discussed.

  18. 32 CFR 11.6 - Crimes and elements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Defense Department of Defense OFFICE OF THE SECRETARY OF DEFENSE MILITARY COMMISSIONS CRIMES AND ELEMENTS FOR TRIALS BY MILITARY COMMISSION § 11.6 Crimes and elements. (a) Substantive offenses—war crimes. The... object of the attack was civilian property, that is, property that was not a military objective; (C) The...

  19. 32 CFR 11.6 - Crimes and elements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Defense Department of Defense OFFICE OF THE SECRETARY OF DEFENSE MILITARY COMMISSIONS CRIMES AND ELEMENTS FOR TRIALS BY MILITARY COMMISSION § 11.6 Crimes and elements. (a) Substantive offenses—war crimes. The... object of the attack was civilian property, that is, property that was not a military objective; (C) The...

  20. 32 CFR 11.6 - Crimes and elements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Defense Department of Defense OFFICE OF THE SECRETARY OF DEFENSE MILITARY COMMISSIONS CRIMES AND ELEMENTS FOR TRIALS BY MILITARY COMMISSION § 11.6 Crimes and elements. (a) Substantive offenses—war crimes. The... object of the attack was civilian property, that is, property that was not a military objective; (C) The...

  1. Mixed methods feasibility study for a trial of blood pressure telemonitoring for people who have had stroke/transient ischaemic attack (TIA).

    PubMed

    Hanley, Janet; Fairbrother, Peter; Krishan, Ashma; McCloughan, Lucy; Padfield, Paul; Paterson, Mary; Pinnock, Hilary; Sheikh, Aziz; Sudlow, Cathie; Todd, Allison; McKinstry, Brian

    2015-03-25

    Good blood pressure (BP) control reduces the risk of recurrence of stroke/transient ischaemic attack (TIA). Although there is strong evidence that BP telemonitoring helps achieve good control, none of the major trials have considered the effectiveness in stroke/TIA survivors. We therefore conducted a feasibility study for a trial of BP telemonitoring for stroke/TIA survivors with uncontrolled BP in primary care. Phase 1 was a pilot trial involving 55 patients stratified by stroke/TIA randomised 3:1 to BP telemonitoring for 6 months or usual care. Phase 2 was a qualitative evaluation and comprised semi-structured interviews with 16 trial participants who received telemonitoring and 3 focus groups with 23 members of stroke support groups and 7 carers. Overall, 125 patients (60 stroke patients, 65 TIA patients) were approached and 55 (44%) patients were randomised including 27 stroke patients and 28 TIA patients. Fifty-two participants (95%) attended the 6-month follow-up appointment, but one declined the second daytime ambulatory blood pressure monitoring (ABPM) measurement resulting in a 93% completion rate for ABPM - the proposed primary outcome measure for a full trial. Adherence to telemonitoring was good; of the 40 participants who were telemonitoring, 38 continued to provide readings throughout the 6 months. There was a mean reduction of 10.1 mmHg in systolic ABPM in the telemonitoring group compared with 3.8 mmHg in the control group, which suggested the potential for a substantial effect from telemonitoring. Our qualitative analysis found that many stroke patients were concerned about their BP and telemonitoring increased their engagement, was easy, convenient and reassuring. A full-scale trial is feasible, likely to recruit well and have good rates of compliance and follow-up. ISRCTN61528726 15/12/2011.

  2. Effect of Resin Ducts and Sap Content on Infestation and Development of Immature Stages of Anastrepha obliqua and Anastrepha ludens (Diptera: Tephritidae) in Four Mango (Sapindales: Anacardiaceae) Cultivars.

    PubMed

    Guillén, Larissa; Adaime, Ricardo; Birke, Andrea; Velázquez, Olinda; Angeles, Guillermo; Ortega, Fernando; Ruíz, Eliel; Aluja, Martín

    2017-04-01

    We determined the influence of resin ducts, sap content, and fruit physicochemical features of four mango cultivars (Criollo, Manila, Ataulfo, and Tommy Atkins) on their susceptibility to the attack of the two most pestiferous fruit fly species infesting mangoes in Mexico: Anastrepha ludens (Loew) and Anastrepha obliqua (Macquart). We performed three studies: 1) analysis of resin ducts in mango fruit exocarp to determine the density and area occupied by resin ducts in each mango cultivar, 2) assessment of mango physicochemical features including fruit sap content, and 3) a forced infestation trial under field conditions using enclosed fruit-bearing branches to expose mangoes to gravid A. ludens or A. obliqua females. Infestation rates, development time from egg to prepupae and pupae, pupal weight, and percent of adult emergence, were assessed. 'Ataulfo' and 'Tommy Atkins' cultivars exhibited the highest resin duct density and sap content, the lowest infestation rate, and had a negative effect on immature development and pupal weight. In sharp contrast, 'Manila' and 'Criollo' cultivars, with the lowest resin duct density and sap content, were highly susceptible to A. ludens and A. obliqua attack. We conclude that sap content and the number, size, and distribution of resin ducts as well as firmness in mango fruit exocarp are all involved in the resistance of mango to A. ludens and A. obliqua attack. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Integrated approach for investigating the durability of self-consolidating concrete to sulfate attack

    NASA Astrophysics Data System (ADS)

    Bassuoni, Mohamed Tamer F.

    The growing use of self-consolidating concrete (SCC) in various infrastructure applications exposed to sulfate-rich environments necessitates conducting comprehensive research to evaluate its durability to external sulfate attack. Since the reliability and adequacy of standard sulfate immersion tests have been questioned, the current thesis introduced an integrated testing approach for assessing the durability of a wide scope of SCC mixtures to external sulfate attack. This testing approach involved progressive levels of complexity from single to multiple damage processes. A new series of sulfate attack tests involving multiple field-like parameters and combined damage mechanisms (various cations, controlled pH, wetting-drying, partial immersion, freezing-thawing, and cyclic cold-hot conditions with or without sustained flexural loading) were designed to evaluate the performance (suitability) of the SCC mixtures under various sulfate attack exposure scenarios. The main mixture design variables of SCC included the type of binder (single, binary, ternary and quaternary), air-entrainment, sand-to-aggregate mass ratio and hybrid fibre reinforcement. The comprehensive database and knowledge obtained from this research were used to develop smart models (fuzzy and neuro-fuzzy inference systems) based on artificial-intelligence to evaluate and predict the performance of the SCC mixtures under various sulfate attack exposure regimes implemented in this study. In full immersion tests involving high concentration sodium and magnesium sulfate solutions with controlled pH, the low penetrability of SCC was responsible for the high durability of specimens. Ternary and quaternary cementitious systems with or without limestone materials provided a passivating layer, with or without acid neutralization capacity, which protected SCC from severe damage in the aggressive sulfuric acid and ammonium sulfate solutions. In contrast to conclusions drawn from the sodium sulfate immersion tests, the combined sulfate attack tests captured performance risks and complex damage mechanisms associated with the SCC pore structure and constituent materials. Sodium sulfate attack with wetting-drying cycles and/or partial immersion under temperate-hot conditions synergistically caused significant damage to specimens, especially to quaternary cementitious systems having very fine pore structure, due to the build-up of salt crystals and sulfate reaction products. The deleterious effects of sulfate reaction products and salt crystallization on all cementitious systems were more severe under the combined sodium sulfate and freezing-thawing exposure, with a potential of sudden brittle failure. Laboratory experiments in the current work documented evidence for the occurrence of thaumasite sulfate attack (TSA) in cementitious systems containing limestone filler, not only under cold but also under temperate-hot conditions, which made specimens more vulnerable to damage in the combined sulfate attack tests. The field-like combined exposure of sodium sulfate, cyclic environments and flexural loading had synergistic effects on SCC specimens and caused the coexistence of multiple-complex degradation mechanisms (sulfate attack, TSA, stress-corrosion, salt crystallization, surface scaling and corrosion of surface steel fibres) depending on the mixture design variables. The current thesis demonstrates that relying only on sulfate immersion tests to evaluate the performance of cement-based materials can be risky. It also shows that linear and deterministic modeling of the performance of concrete structures under external sulfate attack is unrealistic. Fuzzy and adaptive-neuro fuzzy inference systems developed in the current thesis accurately and rationally predicted the serviceability, deterioration in engineering properties and time to failure of the SCC mixtures under the various sulfate attack exposure regimes adopted in the integrated testing approach. A durability evaluation factor from multiple performance criteria was created for the ammonium sulfate exposure. Environmental charts were developed to determine the level of aggression associated with sodium sulfate attack from temperature, RH and degree of wetting-drying expected in service. This novel modeling approach showed promising success in handling complex durability topics such as the sulfate attack of concrete, which involves non-linearity, ambiguity and interface with operator approximation. The current thesis provides needed fundamental knowledge on the durability of a wide scope of SCC mixtures to various sulfate attack exposure scenarios. It elucidates complex deterioration mechanisms and failure modes of cement-based materials under multi-mechanistic aging processes. It also proposes carefully engineered integrated sulfate attack tests that replicate various sulfate attack exposure regimes, which could be refined and standardized in the future. In addition, the current work introduced original knowledge-based smart models capable of handling uncertainty and providing reliable predictions for the behaviour of concrete under external sulfate attack. The models do not require conducting exhaustive laboratory experiments and/or making assumptions, thus facilitating the selection of optimum concrete mixtures for a specified exposure. Overall, this research should effectively contribute to the development of performance-based standards and specifications for, and improvement of durability-based design and life-cycle analysis of concrete structures subjected to external sulfate attack. Keywords. Sulfate attack, self-consolidating concrete, integrated testing, composite cements, air-entrainment, hybrid fibres, full immersion, cations, pH, wetting-drying, partial immersion, freezing-thawing, cyclic cold-hot conditions, flexural loading, thaumasite, salt crystallization, fuzzy, neuro-fuzzy, systems.

  4. An open-label study to evaluate the long-term safety and efficacy of lanadelumab for prevention of attacks in hereditary angioedema: design of the HELP study extension.

    PubMed

    Riedl, Marc A; Bernstein, Jonathan A; Craig, Timothy; Banerji, Aleena; Magerl, Markus; Cicardi, Marco; Longhurst, Hilary J; Shennak, Mustafa M; Yang, William H; Schranz, Jennifer; Baptista, Jovanna; Busse, Paula J

    2017-01-01

    Hereditary angioedema (HAE) is characterized by recurrent attacks of subcutaneous or submucosal edema. Attacks are unpredictable, debilitating, and have a significant impact on quality of life. Patients may be prescribed prophylactic therapy to prevent angioedema attacks. Current prophylactic treatments may be difficult to administer (i.e., intravenously), require frequent administrations or are not well tolerated, and breakthrough attacks may still occur frequently. Lanadelumab is a subcutaneously-administered monoclonal antibody inhibitor of plasma kallikrein in clinical development for prophylaxis of hereditary angioedema attacks. A Phase 1b study supported its efficacy in preventing attacks. A Phase 3, randomized, double-blind, placebo-controlled, parallel-arm study has been completed and an open-label extension is currently ongoing. The primary objective of the open-label extension is to evaluate the long-term safety of repeated subcutaneous administrations of lanadelumab in patients with type I/II HAE. Secondary objectives include evaluation of efficacy and time to first angioedema attack to determine outer bounds of the dosing interval. The study will also evaluate immunogenicity, pharmacokinetics/pharmacodynamics, quality of life, characteristics of breakthrough attacks, ease of self-administration, and safety/efficacy in patients who switch to lanadelumab from another prophylactic therapy. The open-label extension will enroll patients who completed the double-blind study ("rollover patients") and those who did not participate in the double-blind study ("non-rollover patients"), which includes patients who may or may not be currently using another prophylactic therapy. Rollover patients will receive a single 300 mg dose of lanadelumab on Day 0 and the second dose after the patient's first confirmed angioedema attack. Thereafter, lanadelumab will be administered every 2 weeks. Non-rollover patients will receive 300 mg lanadelumab every 2 weeks regardless of the first attack. All patients will receive their last dose on Day 350 (maximum of 26 doses), and will then undergo a 4-week follow-up. Prevention of attacks can reduce the burden of illness associated with HAE. Prophylactic therapy requires extended, repeated dosing and the results of this study will provide important data on the long-term safety and efficacy of lanadelumab, a monoclonal antibody inhibitor of plasma kallikrein for subcutaneous administration for the treatment of HAE. Trial registration NCT02741596.

  5. Aspirin Versus Aspirin Plus Clopidogrel as Antithrombotic Treatment Following Transcatheter Aortic Valve Replacement With a Balloon-Expandable Valve: The ARTE (Aspirin Versus Aspirin + Clopidogrel Following Transcatheter Aortic Valve Implantation) Randomized Clinical Trial.

    PubMed

    Rodés-Cabau, Josep; Masson, Jean-Bernard; Welsh, Robert C; Garcia Del Blanco, Bruno; Pelletier, Marc; Webb, John G; Al-Qoofi, Faisal; Généreux, Philippe; Maluenda, Gabriel; Thoenes, Martin; Paradis, Jean-Michel; Chamandi, Chekrallah; Serra, Vicenç; Dumont, Eric; Côté, Mélanie

    2017-07-10

    The aim of this study was to compare aspirin plus clopidogrel with aspirin alone as antithrombotic treatment following transcatheter aortic valve replacement (TAVR) for the prevention of ischemic events, bleeding events, and death. Few data exist on the optimal antithrombotic therapy following TAVR. This was a randomized controlled trial comparing aspirin (80 to 100 mg/day) plus clopidogrel (75 mg/day) (dual antiplatelet therapy [DAPT]) versus aspirin alone (single-antiplatelet therapy [SAPT]) in patients undergoing TAVR with a balloon-expandable valve. The primary endpoint was the occurrence of death, myocardial infarction (MI), stroke or transient ischemic attack, or major or life-threatening bleeding (according to Valve Academic Research Consortium 2 definitions) within the 3 months following the procedure. The trial was prematurely stopped after the inclusion of 74% of the planned study population. A total of 222 patients were included, 111 allocated to DAPT and 111 to SAPT. The composite of death, MI, stroke or transient ischemic attack, or major or life-threatening bleeding tended to occur more frequently in the DAPT group (15.3% vs. 7.2%, p = 0.065). There were no differences between groups in the occurrence of death (DAPT, 6.3%; SAPT, 3.6%; p = 0.37), MI (DAPT, 3.6%; SAT, 0.9%; p = 0.18), or stroke or transient ischemic attack (DAPT, 2.7%; SAPT, 0.9%; p = 0.31) at 3 months. DAPT was associated with a higher rate of major or life-threatening bleeding events (10.8% vs. 3.6% in the SAPT group, p = 0.038). There were no differences between groups in valve hemodynamic status post-TAVR. This small trial showed that SAPT (vs. DAPT) tended to reduce the occurrence of major adverse events following TAVR. SAPT reduced the risk for major or life-threatening events while not increasing the risk for MI or stroke. Larger studies are needed to confirm these results. (Aspirin Versus Aspirin + Clopidogrel Following Transcatheter Aortic Valve Implantation: The ARTE Trial [ARTE], NCT01559298; Aspirin Versus Aspirin+Clopidogrel as Antithrombotic Treatment Following TAVI [ARTE], NCT02640794). Copyright © 2017 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.

  6. Cost-effectiveness of clopidogrel-aspirin versus aspirin alone for acute transient ischemic attack and minor stroke.

    PubMed

    Pan, Yuesong; Wang, Anxin; Liu, Gaifen; Zhao, Xingquan; Meng, Xia; Zhao, Kun; Liu, Liping; Wang, Chunxue; Johnston, S Claiborne; Wang, Yilong; Wang, Yongjun

    2014-06-05

    Treatment with the combination of clopidogrel and aspirin taken soon after a transient ischemic attack (TIA) or minor stroke was shown to reduce the 90-day risk of stroke in a large trial in China, but the cost-effectiveness is unknown. This study sought to estimate the cost-effectiveness of the clopidogrel-aspirin regimen for acute TIA or minor stroke. A Markov model was created to determine the cost-effectiveness of treatment of acute TIA or minor stroke patients with clopidogrel-aspirin compared with aspirin alone. Inputs for the model were obtained from clinical trial data, claims databases, and the published literature. The main outcome measure was cost per quality-adjusted life-years (QALYs) gained. One-way and multivariable probabilistic sensitivity analyses were performed to test the robustness of the findings. Compared with aspirin alone, clopidogrel-aspirin resulted in a lifetime gain of 0.037 QALYs at an additional cost of CNY 1250 (US$ 192), yielding an incremental cost-effectiveness ratio of CNY 33 800 (US$ 5200) per QALY gained. Probabilistic sensitivity analysis showed that clopidogrel-aspirin therapy was more cost-effective in 95.7% of the simulations at a willingness-to-pay threshold recommended by the World Health Organization of CNY 105 000 (US$ 16 200) per QALY. Early 90-day clopidogrel-aspirin regimen for acute TIA or minor stroke is highly cost-effective in China. Although clopidogrel is generic, Plavix is brand in China. If Plavix were generic, treatment with clopidogrel-aspirin would have been cost saving. © 2014 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley Blackwell.

  7. Complexing Agents and pH Influence on Chemical Durability of Type I Molded Glass Containers.

    PubMed

    Biavati, Alberto; Poncini, Michele; Ferrarini, Arianna; Favaro, Nicola; Scarpa, Martina; Vallotto, Marta

    2017-01-01

    Among the factors that affect the glass surface chemical durability, pH and complexing agents present in aqueous solution have the main role. Glass surface attack can be also related to the delamination issue causing glass particles' appearance in the pharmaceutical preparation. A few methods to check for glass containers delamination propensity and some control guidelines have been proposed. The present study emphasizes the possible synergy between a few complexing agents with pH on borosilicate glass chemical durability.Hydrolytic attack was performed in small-volume 23 mL type I glass containers autoclaved according to the European Pharmacopoeia or United States Pharmacopeia for 1 h at 121 °C, in order to enhance the chemical attack due to time, temperature, and the unfavorable surface/volume ratio. Solutions of 0.048 M or 0.024 M (M/L) of the acids citric, glutaric, acetic, EDTA (ethylenediaminetetraacetic acid), together with sodium phosphate with water for comparison, were used for the trials. The pH was adjusted ±0.05 units at fixed values 5.5, 6.6, 7, 7.4, 8, and 9 by LiOH diluted solution.Because silicon is the main glass network former, silicon release into the attack solutions was chosen as the main index of the glass surface attack and analysed by inductively coupled plasma atomic emission spectrophotometry. The work was completed by the analysis of the silicon release in the worst attack conditions of molded glass, soda lime type II glass, and tubing borosilicate glass vials to compare different glass compositions and forming technologies. Surface analysis by scanning electron microscopy was finally performed to check for the surface status after the worst chemical attack condition by citric acid. LAY ABSTRACT: Glass, like every packaging material, can have some usage limits, mainly in basic pH solutions. The issue of glass surface degradation particles that appear in vials (delamination) has forced a number of drug product recalls in recent years. To prevent such situations, pharmaceutical and biopharmaceutical manufacturers need to understand the reasons for accelerate surface glass corrosion mainly in the case of injectables.Some drugs can contain active components with known ability to corrode glass silica networks. Sometimes these ingredients are dissolved in an alkaline medium that dramatically increases the glass corrosion and potentially causes the issue. As this action is strongly affected by time and temperature, flaking may become visible only after a long storage time. The purpose of this investigation is to verify the borosilicate glass chemical durability during controlled conditions of time and temperature when in contact with testing solutions containing different complexing agents by varying the pH. Si concentration in the extract solution is taken as an index of glass dissolution during constant autoclaving conditions for 1 h at 121 °C, which simulates approximately five years of contact at room temperature.Acetate, citrate, ethylenediaminetetraacetic acid (EDTA), phosphate, and glutarate 0.048 M or 0.024 M solutions were used at increasing pH from 5.5 to 9.0. The chemical durability of two borosilicate tubing glass vials of different glass compositions were compared with the molded one in the worst attack conditions by citric acid. Even if no delamination issue has been experienced by this study in type I molded and tubing containers, the conclusions developed can provide pharmaceutical manufacturers with useful information to prevent glass delamination risk in their processes. © PDA, Inc. 2017.

  8. Effect of Angle of Attack on Slope Climbing Performance

    NASA Technical Reports Server (NTRS)

    Creager, Colin M.; Jones, Lucas; Smith, Lauren M.

    2017-01-01

    Ascending steep slopes is often a very difficult challenge for off-road vehicles, whether on Earth or on extraterrestrial bodies. This challenge is even greater if the surface consists of loose granular soil that does not provide much shear strength. This study investigated how the path at which a vehicle traverses a slope, specifically the angle that it is commanded to drive relative to the base of the hill (the angle of attack), can affect its performance. A vehicle was driven in loose sand at slope angles up to 15 degrees and angles of attack ranging from 10 to 90 degrees. A novel photogrammetry technique was implemented to both track vehicle motion and create a three-dimensional profile of the terrain. This allowed for true wheel sinkage measurements. The study showed that though low angles of attack result in lower wheel slip and sinkage, the efficiency of the vehicles uphill motion increased at higher angles of attack. For slopes up to 15 degrees, a 90 degree angle of attack provided the greatest likelihood of successful ascent.

  9. Finite Energy and Bounded Actuator Attacks on Cyber-Physical Systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Djouadi, Seddik M; Melin, Alexander M; Ferragut, Erik M

    As control system networks are being connected to enterprise level networks for remote monitoring, operation, and system-wide performance optimization, these same connections are providing vulnerabilities that can be exploited by malicious actors for attack, financial gain, and theft of intellectual property. Much effort in cyber-physical system (CPS) protection has focused on protecting the borders of the system through traditional information security techniques. Less effort has been applied to the protection of cyber-physical systems from intelligent attacks launched after an attacker has defeated the information security protections to gain access to the control system. In this paper, attacks on actuator signalsmore » are analyzed from a system theoretic context. The threat surface is classified into finite energy and bounded attacks. These two broad classes encompass a large range of potential attacks. The effect of theses attacks on a linear quadratic (LQ) control are analyzed, and the optimal actuator attacks for both finite and infinite horizon LQ control are derived, therefore the worst case attack signals are obtained. The closed-loop system under the optimal attack signals is given and a numerical example illustrating the effect of an optimal bounded attack is provided.« less

  10. Web Forms and Untraceable DDoS Attacks

    NASA Astrophysics Data System (ADS)

    Jakobsson, Markus; Menczer, Filippo

    We analyze a Web vulnerability that allows an attacker to perform an email-based attack on selected victims, using standard scripts and agents. What differentiates the attack we describe from other, already known forms of distributed denial of service (DDoS) attacks is that an attacker does not need to infiltrate the network in any manner - as is normally required to launch a DDoS attack. Thus, we see this type of attack as a poor man's DDoS. Not only is the attack easy to mount, but it is also almost impossible to trace back to the perpetrator. Along with descriptions of our attack, we demonstrate its destructive potential with (limited and contained) experimental results. We illustrate the potential impact of our attack by describing how an attacker can disable an email account by flooding its inbox; block competition during on-line auctions; harm competitors with an on-line presence; disrupt phone service to a given victim; disconnect mobile corporate leaders from their networks; and disrupt electronic elections. Finally, we propose a set of countermeasures that are light-weight, do not require modifications to the infrastructure, and can be deployed in a gradual manner.

  11. Agronomic performance of Populus deltoides trees engineered for biofuel production

    DOE PAGES

    Macaya-Sanz, David; Chen, Jin?Gui; Kalluri, Udaya C.; ...

    2017-11-30

    Background: One of the major barriers to the development of lignocellulosic feedstocks is the recalcitrance of plant cell walls to deconstruction and saccharification. Recalcitrance can be reduced by targeting genes involved in cell wall biosynthesis, but this can have unintended consequences that compromise the agronomic performance of the trees under field conditions. Here we report the results of a field trial of fourteen distinct transgenic Populus deltoides lines that had previously demonstrated reduced recalcitrance without yield penalties under greenhouse conditions.Results: Survival and productivity of the trial were excellent in the first year, and there was little evidence for reduced performancemore » of the transgenic lines with modified target gene expression. Surprisingly, the most striking phenotypic effects in this trial were for two empty-vector control lines that had modified bud set and bud flush. This is most likely due to somaclonal variation or insertional mutagenesis. Traits related to yield, crown architecture, herbivory, pathogen response, and frost damage showed few significant differences between target gene transgenics and empty vector controls. However, there were a few interesting exceptions. Lines overexpressing the DUF231 gene, a putative O-acetyltransferase, showed early bud flush and marginally increased height growth. Lines overexpressing the DUF266 gene, a putative glycosyltransferase, had significantly decreased stem internode length and slightly higher volume index. Finally, lines overexpressing the PFD2 gene, a putative member of the prefoldin complex, had a slightly reduced volume index.Conclusions: This field trial demonstrates that these cell wall modifications, which decreased cell wall recalcitrance under laboratory conditions, did not seriously compromise first-year performance in the field, despite substantial challenges, including an outbreak of a stem boring insect (Gypsonoma haimbachiana), attack by a leaf rust pathogen (Melampsora spp.), and a late frost event. This bodes well for the potential utility of these lines as advanced biofuels feedstocks.« less

  12. Agronomic performance of Populus deltoides trees engineered for biofuel production

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Macaya-Sanz, David; Chen, Jin?Gui; Kalluri, Udaya C.

    Background: One of the major barriers to the development of lignocellulosic feedstocks is the recalcitrance of plant cell walls to deconstruction and saccharification. Recalcitrance can be reduced by targeting genes involved in cell wall biosynthesis, but this can have unintended consequences that compromise the agronomic performance of the trees under field conditions. Here we report the results of a field trial of fourteen distinct transgenic Populus deltoides lines that had previously demonstrated reduced recalcitrance without yield penalties under greenhouse conditions.Results: Survival and productivity of the trial were excellent in the first year, and there was little evidence for reduced performancemore » of the transgenic lines with modified target gene expression. Surprisingly, the most striking phenotypic effects in this trial were for two empty-vector control lines that had modified bud set and bud flush. This is most likely due to somaclonal variation or insertional mutagenesis. Traits related to yield, crown architecture, herbivory, pathogen response, and frost damage showed few significant differences between target gene transgenics and empty vector controls. However, there were a few interesting exceptions. Lines overexpressing the DUF231 gene, a putative O-acetyltransferase, showed early bud flush and marginally increased height growth. Lines overexpressing the DUF266 gene, a putative glycosyltransferase, had significantly decreased stem internode length and slightly higher volume index. Finally, lines overexpressing the PFD2 gene, a putative member of the prefoldin complex, had a slightly reduced volume index.Conclusions: This field trial demonstrates that these cell wall modifications, which decreased cell wall recalcitrance under laboratory conditions, did not seriously compromise first-year performance in the field, despite substantial challenges, including an outbreak of a stem boring insect (Gypsonoma haimbachiana), attack by a leaf rust pathogen (Melampsora spp.), and a late frost event. This bodes well for the potential utility of these lines as advanced biofuels feedstocks.« less

  13. The role of the emergency services in the optimisation of primary angioplasty: experience from London and the Heart Attack Team.

    PubMed

    Dalby, Miles; Whitbread, Mark

    2013-08-22

    Early ambulance services often confined their activities to a "scoop and run" approach, conveying sick patients quickly to the nearest emergency department. With the advent of modern ST-elevation myocardial infarction (STEMI) management and primary percutaneous coronary intervention (PPCI), the role of the emergency medical service (EMS) has expanded significantly. This review discusses the critical and evolving collaboration between the EMS and the heart attack centre. Speed of reperfusion is a major determinant of outcome in STEMI and, whilst the patient delay (symptom to call time) has a central role in this, system delay (first medical contact to balloon time) is linked to mortality and is used to measure the response of a PPCI programme and is a key element of contemporary guidelines. In addition to rapid diagnosis and transfer to the heart attack centre, the EMS has to deliver a growing number of established treatments including resuscitation and drug therapy. EMS also continually needs to develop expertise in new techniques such as advanced management of cardiac arrest patients, including automated cardiopulmonary resuscitation, and will need to deliver newer therapies if trials support their use, including cooling and preconditioning. Ultimately, the EMS has a central role in the management of STEMI patients which needs to be fully aligned with the heart attack centres. This integration of services is perhaps best regarded as the Heart Attack Team.

  14. Security Assessment of Cyberphysical Digital Microfluidic Biochips.

    PubMed

    Ali, Sk Subidh; Ibrahim, Mohamed; Sinanoglu, Ozgur; Chakrabarty, Krishnendu; Karri, Ramesh

    2016-01-01

    A digital microfluidic biochip (DMFB) is an emerging technology that enables miniaturized analysis systems for point-of-care clinical diagnostics, DNA sequencing, and environmental monitoring. A DMFB reduces the rate of sample and reagent consumption, and automates the analysis of assays. In this paper, we provide the first assessment of the security vulnerabilities of DMFBs. We identify result-manipulation attacks on a DMFB that maliciously alter the assay outcomes. Two practical result-manipulation attacks are shown on a DMFB platform performing enzymatic glucose assay on serum. In the first attack, the attacker adjusts the concentration of the glucose sample and thereby modifies the final result. In the second attack, the attacker tampers with the calibration curve of the assay operation. We then identify denial-of-service attacks, where the attacker can disrupt the assay operation by tampering either with the droplet-routing algorithm or with the actuation sequence. We demonstrate these attacks using a digital microfluidic synthesis simulator. The results show that the attacks are easy to implement and hard to detect. Therefore, this work highlights the need for effective protections against malicious modifications in DMFBs.

  15. Menstrual Migraine: Therapeutic Approaches

    PubMed Central

    2009-01-01

    The development of diagnostic criteria has enabled greater recognition of menstrual migraine as a highly prevalent and disabling condition meriting specific treatment. Although few therapeutic trials have yet been undertaken in accordance with the criteria, the results of those published to date confirm the efficacy of acute migraine drugs for symptomatic treatment. If this approach is insufficient, the predictability of attacks provides the opportunity for perimenstrual prophylaxis. Continuous contraceptive strategies provide an additional option for management, although clinical trial data are limited. Future approaches to treatment could explore the genomic and nongenomic actions of sex steroids. PMID:21180623

  16. Somatotype, Level of Competition, and Performance in Attack in Elite Male Volleyball

    PubMed Central

    Giannopoulos, Nikiforos; Vagenas, George; Noutsos, Konstantinos; Barzouka, Karolina; Bergeles, Nikolaos

    2017-01-01

    Abstract This study investigated the relationship between somatotype, level of competition, and performance in attack in elite level male volleyball players. The objective was to test for the potential covariation of competition level (Division A1 vs. A2) and playing position (hitters vs. centers vs. opposites) considering performance in attack. Anthropometric, body composition and somatotype variables were measured according to the Heath-Carter method. The attack actions of 144 players from 48 volleyball matches were analyzed and their performance was rated using a 5-point numerical scale. Results showed that players of Division A1 were taller, heavier, more muscular, and less endomorphic compared to those of Division A2. MANOVA and follow-up discriminant function analysis revealed somatotype differences among playing positions with centers and opposites being endomorph-ectomorph and hitters being central. Centers performed constantly better than hitters and opposites regardless of the division and somatotype. Multiple linear regression analysis showed that variables defining ectomorph and endomorph players, centers, and players of Division A1 significantly determined the relative performance superiority and were able to explain the variation in performance by almost 25%. These results could be taken into account by coaches when assigning players to particular playing positions or when designing individualized position-specific training programs. PMID:28828084

  17. Somatotype, Level of Competition, and Performance in Attack in Elite Male Volleyball.

    PubMed

    Giannopoulos, Nikiforos; Vagenas, George; Noutsos, Konstantinos; Barzouka, Karolina; Bergeles, Nikolaos

    2017-09-01

    This study investigated the relationship between somatotype, level of competition, and performance in attack in elite level male volleyball players. The objective was to test for the potential covariation of competition level (Division A1 vs. A2) and playing position (hitters vs. centers vs. opposites) considering performance in attack. Anthropometric, body composition and somatotype variables were measured according to the Heath-Carter method. The attack actions of 144 players from 48 volleyball matches were analyzed and their performance was rated using a 5-point numerical scale. Results showed that players of Division A1 were taller, heavier, more muscular, and less endomorphic compared to those of Division A2. MANOVA and follow-up discriminant function analysis revealed somatotype differences among playing positions with centers and opposites being endomorph-ectomorph and hitters being central. Centers performed constantly better than hitters and opposites regardless of the division and somatotype. Multiple linear regression analysis showed that variables defining ectomorph and endomorph players, centers, and players of Division A1 significantly determined the relative performance superiority and were able to explain the variation in performance by almost 25%. These results could be taken into account by coaches when assigning players to particular playing positions or when designing individualized position-specific training programs.

  18. The adaptive function of tiger moth clicks against echolocating bats: an experimental and synthetic approach.

    PubMed

    Ratcliffe, John M; Fullard, James H

    2005-12-01

    We studied the efficiency and effects of the multiple sensory cues of tiger moths on echolocating bats. We used the northern long-eared bat, Myotis septentrionalis, a purported moth specialist that takes surface-bound prey (gleaning) and airborne prey (aerial hawking), and the dogbane tiger moth, Cycnia tenera, an eared species unpalatable to bats that possesses conspicuous colouration and sound-producing organs (tymbals). This is the first study to investigate the interaction of tiger moths and wild-caught bats under conditions mimicking those found in nature and to demand the use of both aerial hawking and gleaning strategies by bats. Further, it is the first to report spectrograms of the sounds produced by tiger moths while under aerial attack by echolocating bats. During both aerial hawking and gleaning trials, all muted C. tenera and perched intact C. tenera were attacked by M. septentrionalis, indicating that M. septentrionalis did not discriminate C. tenera from palatable moths based on potential echoic and/or non-auditory cues. Intact C. tenera were attacked significantly less often than muted C. tenera during aerial hawking attacks: tymbal clicks were therefore an effective deterrent in an aerial hawking context. During gleaning attacks, intact and muted C. tenera were always attacked and suffered similar mortality rates, suggesting that while handling prey this bat uses primarily chemical signals. Our results also show that C. tenera temporally matches the onset of click production to the ;approach phase' echolocation calls produced by aerial hawking attacking bats and that clicks themselves influence the echolocation behaviour of attacking bats. In the context of past research, these findings support the hypotheses that the clicks of arctiid moths are both an active defence (through echolocation disruption) and a reliable indicator of chemical defence against aerial-hawking bats. We suggest these signals are specialized for an aerial context.

  19. Prophylactic Therapy of Cyclic Vomiting Syndrome in Children: Comparison of Amitriptyline and Cyproheptadine: A Randomized Clinical Trial.

    PubMed

    Badihian, Negin; Saneian, Hossein; Badihian, Shervin; Yaghini, Omid

    2018-01-01

    Cyclic vomiting syndrome (CVS) is a common functional gastrointestinal disorder characterized by recurrent episodes of nausea and vomiting. There is no definite treatment for the condition, although some medications are recommended. We aimed to compare the efficacy of amitriptyline and cyproheptadine in prophylactic therapy of CVS. This is a single-blinded randomized clinical trial conducted during 2015-2016 in Isfahan, Iran. Sixty-four children who were 3-15 years old, with a diagnosis of CVS (based on Rome III criteria), were included in the study and were randomly divided into two groups of amitriptyline and cyproheptadine. They were followed for 6 months, looking for frequency and duration of attacks as the primary outcome. The mean monthly frequency of attacks in the last 2 months of the study in the amitriptyline and cyproheptadine group were 0.38±0.55 and 0.59±0.71, respectively (P-value=0.197), after intervention. The mean duration of attacks between amitriptyline and cyproheptadine group were 1.41±2.86 and 1.81±2.22 h, respectively (P-value=0.212). In the amitriptyline group 65.6% of patients reported 100% remission, whereas in the cyproheptadine group 50% reported full remission (P-value=0.206). There was no superiority of one of the medications over the other. We did not find any age-related effect on the efficacy of these medications as well.

  20. Medium-term effectiveness of online behavioral training in migraine self-management: A randomized trial controlled over 10 months.

    PubMed

    Sorbi, M J; Kleiboer, A M; van Silfhout, H G; Vink, G; Passchier, J

    2015-06-01

    This randomized, controlled trial examined the medium-term effectiveness of online behavioral training in migraine self-management (oBT; N = 195) versus waitlist control (WLC; N = 173) on attack frequency, indicators of self-management (primary outcomes), headache top intensity, use of rescue medications, quality of life and disability (secondary outcomes). An online headache diary following the ICHD-II and questionnaires were completed at baseline (T0), post-training (T1) and six months later (T2). Missing data (T1: 24%; T2: 37%) were handled by multiple imputation. We established effect sizes (ES) and tested between-group differences over time with linear mixed modelling techniques based on the intention-to-treat principle. At T2, attack frequency had improved significantly in oBT (-23%, ES = 0.66) but also in WLC (-19%; ES = 0.52). Self-efficacy, internal and external control in migraine management--and triptan use--improved only in oBT, however. This indicates different processes in both groups and could signify (the start of) active self-management in oBT. Also, only oBT improved migraine-specific quality of life to a sizable extent. oBT produced self-management gains but could not account for improved attack frequency, because WLC improved as well. The perspective that BT effects develop gradually, and that online delivery will boost BT outreach, justifies further research. © International Headache Society 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  1. The Economic and Risk Constraints in the Feasibility Analysis of Wireless Communications in Marine Corps Combat Operation Centers

    DTIC Science & Technology

    2013-09-01

    attacker can acquire and use against a wireless infrastructure. Wireless attack tool kits such as the “ Raspberry – PI ” (shown in Figure 10), and...still use a tool such as the Raspberry – PI to perform attacks against a network from outside the controlled area or even inside the controlled area...when considering an insider attack. Figure 10. (From www.howtodocomputing.blogspot.com, n.d.) Wireless – PI is “a collection of pre-configured

  2. Detecting Man-in-the-Middle Attacks against Transport Layer Security Connections with Timing Analysis

    DTIC Science & Technology

    2011-09-15

    Networks (VPNs), TLS protects massive amounts of private information, and protecting this data from Man-in-the-Middle ( MitM ) attacks is imperative to...keeping the information secure. This thesis illustrates how an attacker can successfully perform a MitM attack against a TLS connection without alerting...mechanism a user has against a MitM . The goal for this research is to determine if a time threshold exists that can indicate the presence of a MitM in this

  3. Hypersonic Inlet for a Laser Powered Propulsion System

    NASA Astrophysics Data System (ADS)

    Harrland, Alan; Doolan, Con; Wheatley, Vincent; Froning, Dave

    2011-11-01

    Propulsion within the lightcraft concept is produced via laser induced detonation of an incoming hypersonic air stream. This process requires suitable engine configurations that offer good performance over all flight speeds and angles of attack to ensure the required thrust is maintained. Stream traced hypersonic inlets have demonstrated the required performance in conventional hydrocarbon fuelled scramjet engines, and has been applied to the laser powered lightcraft vehicle. This paper will outline the current methodology employed in the inlet design, with a particular focus on the performance of the lightcraft inlet at angles of attack. Fully three-dimensional turbulent computational fluid dynamics simulations have been performed on a variety of inlet configurations. The performance of the lightcraft inlets have been evaluated at differing angles of attack. An idealized laser detonation simulation has also been performed to validate that the lightcraft inlet does not unstart during the laser powered propulsion cycle.

  4. The Role of Initial Attack and Performer Expertise on Instrument Identification

    ERIC Educational Resources Information Center

    Cassidy, Jane W.; Schlegel, Amanda L.

    2016-01-01

    The purpose of this study was to examine the role initial attack and expertise play in the identification of instrumental tones. A stimulus CD was made of 32 excerpts of instrumental tones. Sixteen possible combinations of the variables of initial attack (present or absent), expertise (beginner versus professional), and timbre (flute, clarinet,…

  5. Known-plaintext attack on the double phase encoding and its implementation with parallel hardware

    NASA Astrophysics Data System (ADS)

    Wei, Hengzheng; Peng, Xiang; Liu, Haitao; Feng, Songlin; Gao, Bruce Z.

    2008-03-01

    A known-plaintext attack on the double phase encryption scheme implemented with parallel hardware is presented. The double random phase encoding (DRPE) is one of the most representative optical cryptosystems developed in mid of 90's and derives quite a few variants since then. Although the DRPE encryption system has a strong power resisting to a brute-force attack, the inherent architecture of DRPE leaves a hidden trouble due to its linearity nature. Recently the real security strength of this opto-cryptosystem has been doubted and analyzed from the cryptanalysis point of view. In this presentation, we demonstrate that the optical cryptosystems based on DRPE architecture are vulnerable to known-plain text attack. With this attack the two encryption keys in the DRPE can be accessed with the help of the phase retrieval technique. In our approach, we adopt hybrid input-output algorithm (HIO) to recover the random phase key in the object domain and then infer the key in frequency domain. Only a plaintext-ciphertext pair is sufficient to create vulnerability. Moreover this attack does not need to select particular plaintext. The phase retrieval technique based on HIO is an iterative process performing Fourier transforms, so it fits very much into the hardware implementation of the digital signal processor (DSP). We make use of the high performance DSP to accomplish the known-plaintext attack. Compared with the software implementation, the speed of the hardware implementation is much fast. The performance of this DSP-based cryptanalysis system is also evaluated.

  6. Recognition of facial expressions of mixed emotions in school-age children exposed to terrorism.

    PubMed

    Scrimin, Sara; Moscardino, Ughetta; Capello, Fabia; Altoè, Gianmarco; Axia, Giovanna

    2009-09-01

    This exploratory study aims at investigating the effects of terrorism on children's ability to recognize emotions. A sample of 101 exposed and 102 nonexposed children (mean age = 11 years), balanced for age and gender, were assessed 20 months after a terrorist attack in Beslan, Russia. Two trials controlled for children's ability to match a facial emotional stimulus with an emotional label and their ability to match an emotional label with an emotional context. The experimental trial evaluated the relation between exposure to terrorism and children's free labeling of mixed emotion facial stimuli created by morphing between 2 prototypical emotions. Repeated measures analyses of covariance revealed that exposed children correctly recognized pure emotions. Four log-linear models were performed to explore the association between exposure group and category of answer given in response to different mixed emotion facial stimuli. Model parameters indicated that, compared with nonexposed children, exposed children (a) labeled facial expressions containing anger and sadness significantly more often than expected as anger, and (b) produced fewer correct answers in response to stimuli containing sadness as a target emotion.

  7. TSARINA: A computer model for assessing conventional and chemical attacks on air bases

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Emerson, D.E.; Wegner, L.H.

    This Note describes the latest version of the TSARINA (TSAR INputs using AIDA) airbase damage assessment computer program that has been developed to estimate the on-base concentration of toxic agents that would be deposited by a chemical attack and to assess losses to various on-base resources from conventional attacks, as well as the physical damage to runways, taxiways, buildings, and other facilities. Although the model may be used as a general-purpose, complex-target damage assessment model, its primary role in intended to be in support of the TSAR (Theater Simulation of Airbase Resources) aircraft sortie generation simulation program. When used withmore » TSAR, multiple trials of a multibase airbase-attack campaign can be assessed with TSARINA, and the impact of those attacks on sortie generation can be derived using the TSAR simulation model. TSARINA, as currently configured, permits damage assessments of attacks on an airbase (or other) complex that is compassed of up to 1000 individual targets (buildings, taxiways, etc,), and 2500 packets of resources. TSARINA determines the actual impact points (pattern centroids for CBUs and container burst point for chemical weapons) by Monte Carlo procedures-i.e., by random selections from the appropriate error distributions. Uncertainties in wind velocity and heading are also considered for chemical weapons. Point-impact weapons that impact within a specified distance of each target type are classed as hits, and estimates of the damage to the structures and to the various classes of support resources are assessed using cookie-cutter weapon-effects approximations.« less

  8. Civil Preparedness and Post-Attack U.S. Economic Recovery. A State-of-the-Art Assessment and Selected Annotated Bibliography.

    DTIC Science & Technology

    1979-10-01

    Although bottlenecks have been discussed thus far in an indus- trial or microeconomic sense, national bottlenecks are possible too, with...Texas Division of Disaster Emergency Services, 1978. JThis workbook provides a detailed format for a multi-meeting workshop to enable local (city/council

  9. BDP Supports First-in-Human Clinical Trials | Frederick National Laboratory for Cancer Research

    Cancer.gov

    Cancer immunotherapy is a type of treatment in which the body’s own immune system is used to attack and kill cancer cells or keep them from spreading. To date, the immunotherapy agent interleukin-2 (IL-2) has been approved by the U.S. Food and Drug

  10. 75 FR 70273 - National Heart, Lung, and Blood Institute; Notice of Closed Meetings

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-17

    ... Institute Special Emphasis Panel, The Antihypertensive and Lipid-Lowering to Prevent Heart Attack Trial... Research Demonstration and Dissemination Projects. Date: December 14, 2010. Time: 8 a.m. to 2 p.m. Agenda... Assistance Program Nos. 93.233, National Center for Sleep Disorders Research; 93.837, Heart and Vascular...

  11. HARPERS FERRY, A PLAY ABOUT JOHN BROWN.

    ERIC Educational Resources Information Center

    STAVIS, BARRIE

    THIS PLAY IS A DRAMATIC RENDERING OF JOHN BROWN'S ATTACK ON THE ARMORY AT HARPERS FERRY AND HIS SUBSEQUENT TRIAL FOR TREASON. ALTHOUGH IT ADHERES TO THE FACTS OF HISTORY, THEY ARE NOT TREATED REALISTICALLY. "HARPERS FERRY" PORTRAYS BROWN AS POSSESSING A PURE IDEALISM UNTAINTED IN THE SLIGHTEST DEGREE BY MATERIALISM OR SELF-SEEKING, WHICH…

  12. GPS Spoofing Attack Characterization and Detection in Smart Grids

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Blum, Rick S.; Pradhan, Parth; Nagananda, Kyatsandra

    The problem of global positioning system (GPS) spoofing attacks on smart grids endowed with phasor measurement units (PMUs) is addressed, taking into account the dynamical behavior of the states of the system. First, it is shown how GPS spoofing introduces a timing synchronization error in the phasor readings recorded by the PMUs and alters the measurement matrix of the dynamical model. Then, a generalized likelihood ratio-based hypotheses testing procedure is devised to detect changes in the measurement matrix when the system is subjected to a spoofing attack. Monte Carlo simulations are performed on the 9-bus, 3-machine test grid to demonstratemore » the implication of the spoofing attack on dynamic state estimation and to analyze the performance of the proposed hypotheses test.« less

  13. Affect Response to Simulated Information Attack during Complex Task Performance

    DTIC Science & Technology

    2014-12-02

    AND FRUSTRATION ........................ 42 FIGURE 27. TASK LOAD INDEX OF MENTAL DEMAND, TEMPORAL DEMAND, AND PHYSICAL DEMAND...situational awareness, affect, and trait characteristics interact with human performance during cyberspace attacks in the physical and information...Operator state was manipulated using emotional stimulation portrayed through the presentation of video segments. The effect of emotions on

  14. X-33 Computational Aeroheating/Aerodynamic Predictions and Comparisons With Experimental Data

    NASA Technical Reports Server (NTRS)

    Hollis, Brian R.; Thompson, Richard A.; Berry, Scott A.; Horvath, Thomas J.; Murphy, Kelly J.; Nowak, Robert J.; Alter, Stephen J.

    2003-01-01

    This report details a computational fluid dynamics study conducted in support of the phase II development of the X-33 vehicle. Aerodynamic and aeroheating predictions were generated for the X-33 vehicle at both flight and wind-tunnel test conditions using two finite-volume, Navier-Stokes solvers. Aerodynamic computations were performed at Mach 6 and Mach 10 wind-tunnel conditions for angles of attack from 10 to 50 with body-flap deflections of 0 to 20. Additional aerodynamic computations were performed over a parametric range of free-stream conditions at Mach numbers of 4 to 10 and angles of attack from 10 to 50. Laminar and turbulent wind-tunnel aeroheating computations were performed at Mach 6 for angles of attack of 20 to 40 with body-flap deflections of 0 to 20. Aeroheating computations were performed at four flight conditions with Mach numbers of 6.6 to 8.9 and angles of attack of 10 to 40. Surface heating and pressure distributions, surface streamlines, flow field information, and aerodynamic coefficients from these computations are presented, and comparisons are made with wind-tunnel data.

  15. Eavesdropping-aware routing and spectrum allocation based on multi-flow virtual concatenation for confidential information service in elastic optical networks

    NASA Astrophysics Data System (ADS)

    Bai, Wei; Yang, Hui; Yu, Ao; Xiao, Hongyun; He, Linkuan; Feng, Lei; Zhang, Jie

    2018-01-01

    The leakage of confidential information is one of important issues in the network security area. Elastic Optical Networks (EON) as a promising technology in the optical transport network is under threat from eavesdropping attacks. It is a great demand to support confidential information service (CIS) and design efficient security strategy against the eavesdropping attacks. In this paper, we propose a solution to cope with the eavesdropping attacks in routing and spectrum allocation. Firstly, we introduce probability theory to describe eavesdropping issue and achieve awareness of eavesdropping attacks. Then we propose an eavesdropping-aware routing and spectrum allocation (ES-RSA) algorithm to guarantee information security. For further improving security and network performance, we employ multi-flow virtual concatenation (MFVC) and propose an eavesdropping-aware MFVC-based secure routing and spectrum allocation (MES-RSA) algorithm. The presented simulation results show that the proposed two RSA algorithms can both achieve greater security against the eavesdropping attacks and MES-RSA can also improve the network performance efficiently.

  16. Security under Uncertainty: Adaptive Attackers Are More Challenging to Human Defenders than Random Attackers

    PubMed Central

    Moisan, Frédéric; Gonzalez, Cleotilde

    2017-01-01

    Game Theory is a common approach used to understand attacker and defender motives, strategies, and allocation of limited security resources. For example, many defense algorithms are based on game-theoretic solutions that conclude that randomization of defense actions assures unpredictability, creating difficulties for a human attacker. However, many game-theoretic solutions often rely on idealized assumptions of decision making that underplay the role of human cognition and information uncertainty. The consequence is that we know little about how effective these algorithms are against human players. Using a simplified security game, we study the type of attack strategy and the uncertainty about an attacker's strategy in a laboratory experiment where participants play the role of defenders against a simulated attacker. Our goal is to compare a human defender's behavior in three levels of uncertainty (Information Level: Certain, Risky, Uncertain) and three types of attacker's strategy (Attacker's strategy: Minimax, Random, Adaptive) in a between-subjects experimental design. Best defense performance is achieved when defenders play against a minimax and a random attack strategy compared to an adaptive strategy. Furthermore, when payoffs are certain, defenders are as efficient against random attack strategy as they are against an adaptive strategy, but when payoffs are uncertain, defenders have most difficulties defending against an adaptive attacker compared to a random attacker. We conclude that given conditions of uncertainty in many security problems, defense algorithms would be more efficient if they are adaptive to the attacker actions, taking advantage of the attacker's human inefficiencies. PMID:28690557

  17. Feasibility randomised multicentre, double-blind, double-dummy controlled trial of anakinra, an interleukin-1 receptor antagonist versus intramuscular methylprednisolone for acute gout attacks in patients with chronic kidney disease (ASGARD): protocol study.

    PubMed

    Balasubramaniam, Gowrie; Parker, Trisha; Turner, David; Parker, Mike; Scales, Jonathan; Harnett, Patrick; Harrison, Michael; Ahmed, Khalid; Bhagat, Sweta; Marianayagam, Thiraupathy; Pitzalis, Costantino; Mallen, Christian; Roddy, Edward; Almond, Mike; Dasgupta, Bhaskar

    2017-09-05

    Acute gout occurs in people with chronic kidney disease, who are commonly older people with comorbidities such as hypertension, heart disease and diabetes. Potentially harmful treatments are administered to these vulnerable patients due to a lack of clear evidence. Newly available treatment that targets a key inflammatory pathway in acute gout attacks provides an opportunity to undertake the first-ever trial specifically looking treating people with kidney disease. This paper describes the protocol for a feasibility randomised controlled trial (RCT) comparing anakinra, a novel interleukin-1 antagonist versus steroids in people with chronic kidney disease (ASGARD). ASGARD is a two-parallel group double-blind, double-dummy multicentre RCT comparing anakinra 100 mg, an interleukin-1 antagonist, subcutaneous for 5 days against intramuscular methylprednisolone 120 mg. The primary objective is to assess the feasibility of the trial design and procedures for a definitive RCT. The specific aims are: (1) test recruitment and retention rates and willingness to be randomised; (2) test eligibility criteria; (3) collect and analyse outcome data to inform sample and power calculations for a trial of efficacy; (4) collect economic data to inform a future economic evaluation estimating costs of treatment and (5) assess capacity of the project to scale up to a national multicentre trial. We will also gather qualitative insights from participants. It aims to recruit 32 patients with a 1:1 randomisation. Information from this feasibility study will help design a definitive trial and provide general information in designing acute gout studies. The London-Central Ethics Committee approved the protocol. The results will be disseminated in peer-reviewed journals and at scientific conferences. EudraCT No. 2015-001787-19, NCT/Clinicalstrials.gov No. NCT02578394, pre-results, WHO Universal Trials Reference No. U1111-1175-1977. NIHR Grant PB-PG-0614-34090. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  18. Low-speed wind tunnel performance of high-speed counterrotation propellers at angle-of-attack

    NASA Technical Reports Server (NTRS)

    Hughes, Christopher E.; Gazzaniga, John A.

    1989-01-01

    The low-speed aerodynamic performance characteristics of two advanced counterrotation pusher-propeller configurations with cruise design Mach numbers of 0.72 were investigated in the NASA Lewis 9- by 15-Foot Low-Speed Wind Tunnel. The tests were conducted at Mach number 0.20, which is representative of the aircraft take-off/landing flight regime. The investigation determined the effect of nonuniform inflow on the propeller performance characteristics for several blade angle settings and a range of rotational speeds. The inflow was varied by yawing the propeller model to angle-of-attack by as much as plus or minus 16 degrees and by installing on the counterrotation propeller test rig near the propeller rotors a model simulator of an aircraft engine support pylon and fuselage. The results of the investigation indicated that the low-speed performance of the counterrotation propeller configurations near the take-off target operating points were reasonable and were fairly insensitive to changes in model angle-of-attack without the aircraft pylon/fuselage simulators installed on the propeller test rig. When the aircraft pylon/fuselage simulators were installed, small changes in propeller performance were seen at zero angle-of-attack, but fairly large changes in total power coefficient and very large changes of aft-to-forward-rotor torque ratio were produced when the propeller model was taken to angle-of-attack. The propeller net efficiency, though, was fairly insensitive to any changes in the propeller flowfield conditions near the take-off target operating points.

  19. Flood Stress as a Technique to Assess Preventive Insecticide and Fungicide Treatments for Protecting Trees against Ambrosia Beetles

    PubMed Central

    Ranger, Christopher M.; Schultz, Peter B.; Reding, Michael E.; Frank, Steven D.; Palmquist, Debra E.

    2016-01-01

    Ambrosia beetles tunnel into the heartwood of trees where they cultivate and feed upon a symbiotic fungus. We assessed the effectiveness of flood stress for making Cercis canadensis L. and Cornus florida L. trees attractive to attack as part of insecticide and fungicide efficacy trials conducted in Ohio and Virginia. Since female ambrosia beetles will not begin ovipositing until their symbiotic fungus is established within the host, we also assessed pre-treatment of trees with permethrin, azoxystrobin, and potassium phosphite on fungal establishment and beetle colonization success. Permethrin reduced attacks on flooded trees, yet no attacks occurred on any of the non-flooded trees. Fewer galleries created within flooded trees pre-treated with permethrin, azoxystrobin, and potassium phosphite contained the purported symbiotic fungus; foundress’ eggs were only detected in flooded but untreated trees. While pre-treatment with permethrin, azoxystrobin, and potassium phosphite can disrupt colonization success, maintaining tree health continues to be the most effective and sustainable management strategy. PMID:27548230

  20. Ticagrelor versus Aspirin in Acute Stroke or Transient Ischemic Attack.

    PubMed

    Johnston, S Claiborne; Amarenco, Pierre; Albers, Gregory W; Denison, Hans; Easton, J Donald; Evans, Scott R; Held, Peter; Jonasson, Jenny; Minematsu, Kazuo; Molina, Carlos A; Wang, Yongjun; Wong, K S Lawrence

    2016-07-07

    Ticagrelor may be a more effective antiplatelet therapy than aspirin for the prevention of recurrent stroke and cardiovascular events in patients with acute cerebral ischemia. We conducted an international double-blind, controlled trial in 674 centers in 33 countries, in which 13,199 patients with a nonsevere ischemic stroke or high-risk transient ischemic attack who had not received intravenous or intraarterial thrombolysis and were not considered to have had a cardioembolic stroke were randomly assigned within 24 hours after symptom onset, in a 1:1 ratio, to receive either ticagrelor (180 mg loading dose on day 1 followed by 90 mg twice daily for days 2 through 90) or aspirin (300 mg on day 1 followed by 100 mg daily for days 2 through 90). The primary end point was the time to the occurrence of stroke, myocardial infarction, or death within 90 days. During the 90 days of treatment, a primary end-point event occurred in 442 of the 6589 patients (6.7%) treated with ticagrelor, versus 497 of the 6610 patients (7.5%) treated with aspirin (hazard ratio, 0.89; 95% confidence interval [CI], 0.78 to 1.01; P=0.07). Ischemic stroke occurred in 385 patients (5.8%) treated with ticagrelor and in 441 patients (6.7%) treated with aspirin (hazard ratio, 0.87; 95% CI, 0.76 to 1.00). Major bleeding occurred in 0.5% of patients treated with ticagrelor and in 0.6% of patients treated with aspirin, intracranial hemorrhage in 0.2% and 0.3%, respectively, and fatal bleeding in 0.1% and 0.1%. In our trial involving patients with acute ischemic stroke or transient ischemic attack, ticagrelor was not found to be superior to aspirin in reducing the rate of stroke, myocardial infarction, or death at 90 days. (Funded by AstraZeneca; ClinicalTrials.gov number, NCT01994720.).

  1. Identifying and tracking attacks on networks: C3I displays and related technologies

    NASA Astrophysics Data System (ADS)

    Manes, Gavin W.; Dawkins, J.; Shenoi, Sujeet; Hale, John C.

    2003-09-01

    Converged network security is extremely challenging for several reasons; expanded system and technology perimeters, unexpected feature interaction, and complex interfaces all conspire to provide hackers with greater opportunities for compromising large networks. Preventive security services and architectures are essential, but in and of themselves do not eliminate all threat of compromise. Attack management systems mitigate this residual risk by facilitating incident detection, analysis and response. There are a wealth of attack detection and response tools for IP networks, but a dearth of such tools for wireless and public telephone networks. Moreover, methodologies and formalisms have yet to be identified that can yield a common model for vulnerabilities and attacks in converged networks. A comprehensive attack management system must coordinate detection tools for converged networks, derive fully-integrated attack and network models, perform vulnerability and multi-stage attack analysis, support large-scale attack visualization, and orchestrate strategic responses to cyber attacks that cross network boundaries. We present an architecture that embodies these principles for attack management. The attack management system described engages a suite of detection tools for various networking domains, feeding real-time attack data to a comprehensive modeling, analysis and visualization subsystem. The resulting early warning system not only provides network administrators with a heads-up cockpit display of their entire network, it also supports guided response and predictive capabilities for multi-stage attacks in converged networks.

  2. Security issues of Internet-based biometric authentication systems: risks of Man-in-the-Middle and BioPhishing on the example of BioWebAuth

    NASA Astrophysics Data System (ADS)

    Zeitz, Christian; Scheidat, Tobias; Dittmann, Jana; Vielhauer, Claus; González Agulla, Elisardo; Otero Muras, Enrique; García Mateo, Carmen; Alba Castro, José L.

    2008-02-01

    Beside the optimization of biometric error rates the overall security system performance in respect to intentional security attacks plays an important role for biometric enabled authentication schemes. As traditionally most user authentication schemes are knowledge and/or possession based, firstly in this paper we present a methodology for a security analysis of Internet-based biometric authentication systems by enhancing known methodologies such as the CERT attack-taxonomy with a more detailed view on the OSI-Model. Secondly as proof of concept, the guidelines extracted from this methodology are strictly applied to an open source Internet-based biometric authentication system (BioWebAuth). As case studies, two exemplary attacks, based on the found security leaks, are investigated and the attack performance is presented to show that during the biometric authentication schemes beside biometric error performance tuning also security issues need to be addressed. Finally, some design recommendations are given in order to ensure a minimum security level.

  3. Low speed and angle of attack effects on sonic and near-sonic inlets

    NASA Technical Reports Server (NTRS)

    Hickcox, T. E.; Lawrence, R. L.; Syberg, J.; Wiley, D. R.

    1975-01-01

    Tests of the Quiet, Clean Short-Haul Experimental Engine (QCSEE) were conducted to determine the effects of forward velocity and angle of attack on sonic and near-sonic inlet aerodynamic performance penalties and acoustic suppression characteristics. The tests demonstrate that translating centerbody and radial vane sonic inlets, and QCSEE high throat Mach number inlets, can be designed to operate effectively at forward speed and moderate angle of attack with good performance and noise suppression capability. The test equipment and procedures used in conducting the evaluation are described. Results of the tests are presented in tabular form.

  4. A study on efficient detection of network-based IP spoofing DDoS and malware-infected Systems.

    PubMed

    Seo, Jung Woo; Lee, Sang Jin

    2016-01-01

    Large-scale network environments require effective detection and response methods against DDoS attacks. Depending on the advancement of IT infrastructure such as the server or network equipment, DDoS attack traffic arising from a few malware-infected systems capable of crippling the organization's internal network has become a significant threat. This study calculates the frequency of network-based packet attributes and analyzes the anomalies of the attributes in order to detect IP-spoofed DDoS attacks. Also, a method is proposed for the effective detection of malware infection systems triggering IP-spoofed DDoS attacks on an edge network. Detection accuracy and performance of the collected real-time traffic on a core network is analyzed thru the use of the proposed algorithm, and a prototype was developed to evaluate the performance of the algorithm. As a result, DDoS attacks on the internal network were detected in real-time and whether or not IP addresses were spoofed was confirmed. Detecting hosts infected by malware in real-time allowed the execution of intrusion responses before stoppage of the internal network caused by large-scale attack traffic.

  5. Secure Fusion Estimation for Bandwidth Constrained Cyber-Physical Systems Under Replay Attacks.

    PubMed

    Chen, Bo; Ho, Daniel W C; Hu, Guoqiang; Yu, Li; Bo Chen; Ho, Daniel W C; Guoqiang Hu; Li Yu; Chen, Bo; Ho, Daniel W C; Hu, Guoqiang; Yu, Li

    2018-06-01

    State estimation plays an essential role in the monitoring and supervision of cyber-physical systems (CPSs), and its importance has made the security and estimation performance a major concern. In this case, multisensor information fusion estimation (MIFE) provides an attractive alternative to study secure estimation problems because MIFE can potentially improve estimation accuracy and enhance reliability and robustness against attacks. From the perspective of the defender, the secure distributed Kalman fusion estimation problem is investigated in this paper for a class of CPSs under replay attacks, where each local estimate obtained by the sink node is transmitted to a remote fusion center through bandwidth constrained communication channels. A new mathematical model with compensation strategy is proposed to characterize the replay attacks and bandwidth constrains, and then a recursive distributed Kalman fusion estimator (DKFE) is designed in the linear minimum variance sense. According to different communication frameworks, two classes of data compression and compensation algorithms are developed such that the DKFEs can achieve the desired performance. Several attack-dependent and bandwidth-dependent conditions are derived such that the DKFEs are secure under replay attacks. An illustrative example is given to demonstrate the effectiveness of the proposed methods.

  6. Gait biometrics under spoofing attacks: an experimental investigation

    NASA Astrophysics Data System (ADS)

    Hadid, Abdenour; Ghahramani, Mohammad; Kellokumpu, Vili; Feng, Xiaoyi; Bustard, John; Nixon, Mark

    2015-11-01

    Gait is a relatively biometric modality which has a precious advantage over other modalities, such as iris and voice, in that it can be easily captured from a distance. Although it has recently become a topic of great interest in biometric research, there has been little investigation into gait spoofing attacks where a person tries to imitate the clothing or walking style of someone else. We recently analyzed for the first time the effects of spoofing attacks on silhouette-based gait biometric systems and showed that it was indeed possible to spoof gait biometric systems by clothing impersonation and the deliberate selection of a target that has a similar build to the attacker. To gain deeper insight into the performance of current gait biometric systems under spoofing attacks, we provide a thorough investigation on how clothing can be used to spoof a target and evaluate the performance of two state-of-the-art recognition methods on a gait spoofing database recorded at the University of Southampton. Furthermore, we describe and evaluate an initial solution coping with gait spoofing attacks. The obtained results are very promising and point out interesting findings which can be used for future investigations.

  7. Attack-tolerant networked control system: an approach for detection the controller stealthy hijacking attack

    NASA Astrophysics Data System (ADS)

    Atta Yaseen, Amer; Bayart, Mireille

    2017-01-01

    In this work, a new approach will be introduced as a development for the attack-tolerant scheme in the Networked Control System (NCS). The objective is to be able to detect an attack such as the Stuxnet case where the controller is reprogrammed and hijacked. Besides the ability to detect the stealthy controller hijacking attack, the advantage of this approach is that there is no need for a priori mathematical model of the controller. In order to implement the proposed scheme, a specific detector for the controller hijacking attack is designed. The performance of this scheme is evaluated be connected the detector to NCS with basic security elements such as Data Encryption Standard (DES), Message Digest (MD5), and timestamp. The detector is tested along with networked PI controller under stealthy hijacking attack. The test results of the proposed method show that the hijacked controller can be significantly detected and recovered.

  8. Assessment of aerodynamic performance of V/STOL and STOVL fighter aircraft

    NASA Technical Reports Server (NTRS)

    Nelms, W. P.

    1984-01-01

    The aerodynamic performance of V/STOL and STOVL fighter/attack aircraft was assessed. Aerodynamic and propulsion/airframe integration activities are described and small and large scale research programs are considered. Uncertainties affecting aerodynamic performance that are associated with special configuration features resulting from the V/STOL requirement are addressed. Example uncertainties relate to minimum drag, wave drag, high angle of attack characteristics, and power induced effects.

  9. Sodium oxybate for cataplexy.

    PubMed

    Lemon, Michael D; Strain, Joe D; Farver, Debra K

    2006-03-01

    To review the pharmacology, pharmacokinetics, clinical efficacy, adverse effects, drug interactions, precautions, dosing recommendations, and patient counseling of sodium oxybate for the treatment of cataplexy in patients with narcolepsy. OVID and PubMed databases were searched (1966-January 2006) using the key words sodium oxybate, gamma-hydroxybutyrate, narcolepsy, and cataplexy. Only English-language articles were selected. All information on sodium oxybate related to narcolepsy and cataplexy was considered. Study selection included human trials evaluating safety and efficacy of sodium oxybate for the treatment of cataplexy. Sodium oxybate is approved by the Food and Drug Administration for the treatment of excessive daytime sleepiness and cataplexy in patients with narcolepsy. In placebo-controlled trials, sodium oxybate demonstrated efficacy in reducing the number of cataplexy attacks. The dosing regimen includes a split dose given at bedtime and 2.5-4 hours later due to its short elimination half-life. The drug is generally well tolerated, with headache, nausea, dizziness, pain, and somnolence being the most common adverse events. Sodium oxybate is safe and effective for the treatment of cataplexy. Potential disadvantages include a multiple dosing regimen, abuse potential, cost, and a closed distribution system. Potential advantages demonstrated in clinical trials include significant decreases in the number of weekly cataplexy attacks, improvement in daytime sleepiness, and improvement in the Clinical Global Impression of Change score and nighttime awakenings. Overall, sodium oxybate provides a new option for the treatment of cataplexy.

  10. Weight loss for overweight and obese individuals with gout: a systematic review of longitudinal studies.

    PubMed

    Nielsen, Sabrina M; Bartels, Else M; Henriksen, Marius; Wæhrens, Eva E; Gudbergsen, Henrik; Bliddal, Henning; Astrup, Arne; Knop, Filip K; Carmona, Loreto; Taylor, William J; Singh, Jasvinder A; Perez-Ruiz, Fernando; Kristensen, Lars E; Christensen, Robin

    2017-11-01

    Weight loss is commonly recommended for gout, but the magnitude of the effect has not been evaluated in a systematic review. The aim of this systematic review was to determine benefits and harms associated with weight loss in overweight and obese patients with gout. We searched six databases for longitudinal studies, reporting the effect of weight loss in overweight/obese gout patients. Risk of bias was assessed using the tool Risk of Bias in Non-Randomised Studies of Interventions. The quality of evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation. From 3991 potentially eligible studies, 10 were included (including one randomised trial). Interventions included diet with/without physical activity, bariatric surgery, diuretics, metformin or no intervention. Mean weight losses ranged from 3 kg to 34 kg. Clinical heterogeneity in study characteristics precluded meta-analysis. The effect on serum uric acid (sUA) ranged from -168 to 30 μmol/L, and 0%-60% patients achieving sUA target (<360 μmol/L). Six out of eight studies (75%) showed beneficial effects on gout attacks. Two studies indicated dose-response relationship for sUA, achieving sUA target and gout attacks. At short term, temporary increased sUA and gout attacks tended to occur after bariatric surgery. The available evidence is in favour of weight loss for overweight/obese gout patients, with low, moderate and low quality of evidence for effects on sUA, achieving sUA target and gout attacks, respectively. At short term, unfavourable effects may occur. Since the current evidence consists of a few studies (mostly observational) of low methodological quality, there is an urgent need to initiate rigorous prospective studies (preferably randomised controlled trials). PROSPERO, CRD42016037937. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  11. Cinnarizine in refractory migraine prophylaxis: efficacy and tolerability. A comparison with sodium valproate.

    PubMed

    Togha, Mansoureh; Mansoureh, Togha; Rahmat Jirde, Masoud; Nilavari, Kiafar; Ashrafian, Hosein; Razeghi, Soodeh; Kohan, Leila

    2008-04-01

    This was a double-blind clinical trial designed to assess the efficacy and safety of the cinnarizine (CIN) in patients with migraine who were refractory to propranolol and tricyclic antidepressants in comparison with sodium valproate (SV) to investigate whether CIN could be at least as effective as SV. A total of 125 patients were treated in a treatment period of 12 weeks. All patients had at least one intake of trial medication and 2-week post baseline efficacy observation which all were included in the ITT analysis. Of the 125 subjects treated, 46 discontinued prematurely: 25 from the CIN and 21 from the SV group. The main reasons for premature discontinuation were: lost to follow up (25/46, 63.2%), insufficient response (16/46, 20%), and adverse events (5/46, 12.8%). No statistically significant inter-group differences in the number of discontinuation was observed (p > 0.05). In both groups, number of attacks, intensity, and duration of attacks significantly decreased (p < 0.05). No statistically significant inter-group differences were observed regarding the mean number of attacks, duration, and intensity of migraine attacks for any of the time intervals analysed, except for the mean reduction of third and fourth visits intensity from baseline which were significantly different in two groups (p < 0.05), with the CIN group showing more reduction. Analysis of the number of responders showed that in the CIN group 61.2% subjects were responders, and 63.8% in the SV group. No statistically significant differences between the treatment groups were found for any of the secondary parameters. Overall 26 subjects reported one or more adverse events during the study period: 13 subjects in each group. Five subjects discontinued prematurely due to adverse events; two in the CIN group with significant weight gain, and 3 in the SV group with significant weight gain and severe tremor. These results suggest that CIN is an effective and safe prophylactic agent even in severe migraine headache.

  12. Results from flight and simulator studies of a Mach 3 cruise longitudinal autopilot

    NASA Technical Reports Server (NTRS)

    Gilyard, G. B.; Smith, J. W.

    1978-01-01

    At Mach numbers of approximately 3.0 and altitudes greater than 21,300 meters, the original altitude and Mach hold modes of the YF-12 autopilot produced aircraft excursions that were erratic or divergent, or both. Flight data analysis and simulator studies showed that the sensitivity of the static pressure port to angle of attack had a detrimental effect on the performance of the altitude and Mach hold modes. Good altitude hold performance was obtained when a high passed pitch rate feedback was added to compensate for angle of attack sensitivity and the altitude error and integral altitude gains were reduced. Good Mach hold performance was obtained when the angle of attack sensitivity was removed; however, the ride qualities remained poor.

  13. Corrosion Performance of Inconel 625 in High Sulphate Content

    NASA Astrophysics Data System (ADS)

    Ismail, Azzura

    2016-05-01

    Inconel 625 (UNS N06625) is a type of nickel-chromium-molybdenum alloy with excellent corrosion resistance in a wide range of corrosive media, being especially resistant to pitting and crevice corrosion. However, in aggressive environment, Inconel 625 will suffer corrosion attack like other metals. This research compared the corrosion performance of Inconel 625 when exposed to higher sulphate content compared to real seawater. The results reveal that Inconel 625 is excellent in resist the corrosion attack in seawater. However, at increasing temperature, the corrosion resistance of this metal decrease. The performance is same in seawater with high sulphate content at increasing temperature. It can be concluded that sulphate promote perforation on Inconel 625 and become aggressive agents that accelerate the corrosion attack.

  14. Towards Reliable Evaluation of Anomaly-Based Intrusion Detection Performance

    NASA Technical Reports Server (NTRS)

    Viswanathan, Arun

    2012-01-01

    This report describes the results of research into the effects of environment-induced noise on the evaluation process for anomaly detectors in the cyber security domain. This research was conducted during a 10-week summer internship program from the 19th of August, 2012 to the 23rd of August, 2012 at the Jet Propulsion Laboratory in Pasadena, California. The research performed lies within the larger context of the Los Angeles Department of Water and Power (LADWP) Smart Grid cyber security project, a Department of Energy (DoE) funded effort involving the Jet Propulsion Laboratory, California Institute of Technology and the University of Southern California/ Information Sciences Institute. The results of the present effort constitute an important contribution towards building more rigorous evaluation paradigms for anomaly-based intrusion detectors in complex cyber physical systems such as the Smart Grid. Anomaly detection is a key strategy for cyber intrusion detection and operates by identifying deviations from profiles of nominal behavior and are thus conceptually appealing for detecting "novel" attacks. Evaluating the performance of such a detector requires assessing: (a) how well it captures the model of nominal behavior, and (b) how well it detects attacks (deviations from normality). Current evaluation methods produce results that give insufficient insight into the operation of a detector, inevitably resulting in a significantly poor characterization of a detectors performance. In this work, we first describe a preliminary taxonomy of key evaluation constructs that are necessary for establishing rigor in the evaluation regime of an anomaly detector. We then focus on clarifying the impact of the operational environment on the manifestation of attacks in monitored data. We show how dynamic and evolving environments can introduce high variability into the data stream perturbing detector performance. Prior research has focused on understanding the impact of this variability in training data for anomaly detectors, but has ignored variability in the attack signal that will necessarily affect the evaluation results for such detectors. We posit that current evaluation strategies implicitly assume that attacks always manifest in a stable manner; we show that this assumption is wrong. We describe a simple experiment to demonstrate the effects of environmental noise on the manifestation of attacks in data and introduce the notion of attack manifestation stability. Finally, we argue that conclusions about detector performance will be unreliable and incomplete if the stability of attack manifestation is not accounted for in the evaluation strategy.

  15. Cost-effectiveness of gammaCore (non-invasive vagus nerve stimulation) for acute treatment of episodic cluster headache.

    PubMed

    Mwamburi, Mkaya; Liebler, Eric J; Tenaglia, Andrew T

    2017-11-01

    Cluster headache is a debilitating disease characterized by excruciatingly painful attacks that affects 0.15% to 0.4% of the US population. Episodic cluster headache manifests as circadian and circannual seasonal bouts of attacks, each lasting 15 to 180 minutes, with periods of remission. In chronic cluster headache, the attacks occur throughout the year with no periods of remission. While existing treatments are effective for some patients, many patients continue to suffer. There are only 2 FDA-approved medications for episodic cluster headache in the United States, while others, such as high-flow oxygen, are used off-label. Episodic cluster headache is associated with comorbidities and affects work, productivity, and daily functioning. The economic burden of episodic cluster headache is considerable, costing more than twice that of nonheadache patients. gammaCore adjunct to standard of care (SoC) was found to have superior efficacy in treatment of acute episodic cluster headaches compared with sham-gammaCore used with SoC in ACT1 and ACT2 trials. However, the economic impact has not been characterized for this indication. We conducted a cost-effectiveness analysis of gammaCore adjunct to SoC compared with SoC alone for the treatment of acute pain associated with episodic cluster headache attacks. The model structure was based on treatment of acute attacks with 3 outcomes: failures, nonresponders, and responders. The time horizon of the model is 1 year using a payer perspective with uncertainty incorporated. Parameter inputs were derived from primary data from the randomized controlled trials for gammaCore. The mean annual costs associated with the gammaCore-plus-SoC arm was $9510, and mean costs for the SoC-alone arm was $10,040. The mean quality-adjusted life years for gammaCore-plus-SoC arm were 0.83, and for the SoC-alone arm, they were 0.74. The gammaCore-plus-SoC arm was dominant over SoC alone. All 1-way and multiway sensitivity analyses were cost-effective using a threshold of $20,000. gammaCore dominance, representing savings, was driven by superior efficacy, improvement in quality of life (QoL), and reduction in costs associated with successful and consistent abortion of episodic attacks. These findings serve as additional economic evidence to support coverage for gammaCore. Additional real-world data are needed to characterize the long-term impact of gammaCore on comorbidities, utilization, QoL, daily functioning, productivity, and social engagement of these patients, and for other indications.

  16. Optimal management of severe nausea and vomiting in migraine: improving patient outcomes

    PubMed Central

    Láinez, Miguel JA; García-Casado, Ana; Gascón, Francisco

    2013-01-01

    Migraine is a common and potentially disabling disorder for patients, with wide-reaching implications for health care services, society, and the economy. Nausea and vomiting during migraine attacks are common symptoms that affect at least 60% of patients suffering from migraines. These symptoms are often more disabling than the headache itself, causing a great burden on the patient’s life. Nausea and vomiting may delay the use of oral abortive medication or interfere with oral drug absorption. Therefore, they can hinder significantly the management and treatment of migraine (which is usually given orally). The main treatment of pain-associated symptoms of migraine (such as nausea and vomiting) is to stop the migraine attack itself as soon as possible, with the effective drugs at the effective doses, seeking if necessary alternative routes of administration. In some cases, intravenous antiemetic drugs are able to relieve a migraine attack and associated symptoms like nausea and vomiting. We performed an exhaustive PubMed search of the English literature to find studies about management of migraine and its associated symptoms. Search terms were migraine, nausea, and vomiting. We did not limit our search to a specific time period. We focused on clinical efficacy and tolerance of the various drugs and procedures based on data from human studies. We included the best available studies for each discussed drug or procedure. These ranged from randomized controlled trials for some treatments to small case series for others. Recently updated books and manuals on neurology and headache were also consulted. We herein review the efficacy of the different approaches in order to manage nausea and vomiting for migraine patents. PMID:24143125

  17. Predicting Major Bleeding in Ischemic Stroke Patients With Atrial Fibrillation.

    PubMed

    Hilkens, Nina A; Algra, Ale; Greving, Jacoba P

    2017-11-01

    Performance of risk scores for major bleeding in patients with atrial fibrillation and a previous transient ischemic attack or ischemic stroke is not well established. We aimed to validate risk scores for major bleeding in patients with atrial fibrillation treated with oral anticoagulants after cerebral ischemia and explore the net benefit of oral anticoagulants among bleeding risk categories. We analyzed 3623 patients with a history of transient ischemic attack or stroke included in the RE-LY trial (Randomized Evaluation of Long-Term Anticoagulation Therapy). We assessed performance of HEMORR 2 HAGES (hepatic or renal disease, ethanol abuse, malignancy, older age, reduced platelet count or function, hypertension [uncontrolled], anemia, genetic factors, excessive fall risk, and stroke), Shireman, HAS-BLED (hypertension, abnormal renal/liver function, stroke, bleeding history or predisposition, labile international normalized ratio, elderly, drugs/alcohol concomitantly), ATRIA (Anticoagulation and Risk Factors in Atrial Fibrillation), and ORBIT scores (older age, reduced haemoglobin/haematocrit/history of anaemia, bleeding history, insufficient kidney function, and treatment with antiplatelet) with C statistics and calibration plots. Net benefit of oral anticoagulants was explored by comparing risk reduction in ischemic stroke with risk increase in major bleedings on warfarin. During 6922 person-years of follow-up, 266 patients experienced a major bleed (3.8 per 100 person-years). C statistics ranged from 0.62 (Shireman) to 0.67 (ATRIA). Calibration was poor for ATRIA and moderate for other models. The reduction in recurrent ischemic strokes on warfarin was larger than the increase in major bleeding risk, irrespective of bleeding risk category. Performance of prediction models for major bleeding in patients with cerebral ischemia and atrial fibrillation is modest but comparable with performance in patients with only atrial fibrillation. Bleeding risk scores cannot guide treatment decisions for oral anticoagulants but may still be useful to identify modifiable risk factors for bleeding. Clinical usefulness may be best for ORBIT, which is based on a limited number of easily obtainable variables and showed reasonable performance. © 2017 American Heart Association, Inc.

  18. An experimental study of an airfoil with a bio-inspired leading edge device at high angles of attack

    NASA Astrophysics Data System (ADS)

    Mandadzhiev, Boris A.; Lynch, Michael K.; Chamorro, Leonardo P.; Wissa, Aimy A.

    2017-09-01

    Robust and predictable aerodynamic performance of unmanned aerial vehicles at the limits of their design envelope is critical for safety and mission adaptability. Deployable aerodynamic surfaces from the wing leading or trailing edges are often used to extend the aerodynamic envelope (e.g. slats and flaps). Birds have also evolved feathers at the leading edge (LE) of their wings, known as the alula, which enables them to perform high angles of attack maneuvers. In this study, a series of wind tunnel experiments are performed to quantify the effect of various deployment parameters of an alula-like LE device on the aerodynamic performance of a cambered airfoil (S1223) at stall and post stall conditions. The alula relative angle of attack, measured from the mean chord of the airfoil, is varied to modulate tip-vortex strength, while the alula deflection angle is varied to modulate the distance between the tip vortex and the wing surface. Integrated lift force measurements were collected at various alula-inspired device configurations. The effect of the alula-inspired device on the boundary layer velocity profile and turbulence intensity were investigated through hot-wire anemometer measurements. Results show that as alula deflection angle increases, the lift coefficient also increase especially at lower alula relative angles of attack. Moreover, at post stall wing angles of attack, the wake velocity deficit is reduced in the presence of alula device, confirming the mitigation of the wing adverse pressure gradient. The results are in strong agreement with measurements taken on bird wings showing delayed flow reversal and extended range of operational angles of attack. An engineered alula-inspired device has the potential to improve mission adaptability in small unmanned air vehicles during low Reynolds number flight.

  19. The non-trusty clown attack on model-based speaker recognition systems

    NASA Astrophysics Data System (ADS)

    Farrokh Baroughi, Alireza; Craver, Scott

    2015-03-01

    Biometric detectors for speaker identification commonly employ a statistical model for a subject's voice, such as a Gaussian Mixture Model, that combines multiple means to improve detector performance. This allows a malicious insider to amend or append a component of a subject's statistical model so that a detector behaves normally except under a carefully engineered circumstance. This allows an attacker to force a misclassification of his or her voice only when desired, by smuggling data into a database far in advance of an attack. Note that the attack is possible if attacker has access to database even for a limited time to modify victim's model. We exhibit such an attack on a speaker identification, in which an attacker can force a misclassification by speaking in an unusual voice, and replacing the least weighted component of victim's model by the most weighted competent of the unusual voice of the attacker's model. The reason attacker make his or her voice unusual during the attack is because his or her normal voice model can be in database, and by attacking with unusual voice, the attacker has the option to be recognized as himself or herself when talking normally or as the victim when talking in the unusual manner. By attaching an appropriately weighted vector to a victim's model, we can impersonate all users in our simulations, while avoiding unwanted false rejections.

  20. Sumatriptan (rectal route of administration) for acute migraine attacks in adults

    PubMed Central

    Derry, Christopher J; Derry, Sheena; Moore, R Andrew

    2014-01-01

    Background Migraine is a highly disabling condition for the individual and also has wide-reaching implications for society, healthcare services, and the economy. Sumatriptan is an abortive medication for migraine attacks, belonging to the triptan family. Rectal administration may be preferable to oral for individuals experiencing nausea and/or vomiting. Objectives To determine the efficacy and tolerability of rectal sumatriptan compared to placebo and other active interventions in the treatment of acute migraine attacks in adults. Search methods We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, online databases, and reference lists for studies through 13 October 2011. Selection criteria We included randomised, double-blind, placebo- and/or active-controlled studies using rectally administered sumatriptan to treat a migraine headache episode, with at least 10 participants per treatment arm. Data collection and analysis Two review authors independently assessed trial quality and extracted data. We used numbers of participants achieving each outcome to calculate relative risk (or ‘risk ratio’) and numbers needed to treat to benefit (NNT) or harm (NNH) compared to placebo or a different active treatment. Main results Three studies (866 participants) compared rectally administered sumatriptan with placebo or an active comparator. Most of the data were for the 12.5 mg and 25 mg doses. For the majority of efficacy outcomes, sumatriptan surpassed placebo. For sumatriptan 12.5 mg versus placebo the NNTs were 5.2 and 3.2 for headache relief at one and two hours, respectively. Results for the 25 mg dose were similar to the 12.5 mg dose, and there were no significant differences between the two doses for any of the outcomes analysed. The NNTs for sumatriptan 25 mg versus placebo were 4.2, 3.2, and 2.4 for pain-free at two hours, headache relief at one hour, and headache relief at two hours, respectively. Relief of functional disability was greater with sumatriptan than with placebo, with NNTs of 8.0 and 4.0 for the 12.5 mg and 25 mg doses, respectively. For the most part, adverse events were transient and mild and were more common with sumatriptan than with placebo, but there were insufficient data to perform any analyses. Direct comparison of sumatriptan with active treatments was limited to one study comparing sumatriptan 25 mg with ergotamine tartrate 2 mg + caffeine 100 mg. Authors’ conclusions Based on limited amounts of data, sumatriptan 25 mg, administered rectally, is an effective treatment for acute migraine attacks, with participants in these studies experiencing a significant reduction in headache pain and functional disability within two hours of treatment. The lack of data on relief of headache-associated symptoms or incidence of adverse events limits any conclusions that can be drawn. PMID:22336868

  1. Selective neuronal lapses precede human cognitive lapses following sleep deprivation.

    PubMed

    Nir, Yuval; Andrillon, Thomas; Marmelshtein, Amit; Suthana, Nanthia; Cirelli, Chiara; Tononi, Giulio; Fried, Itzhak

    2017-12-01

    Sleep deprivation is a major source of morbidity with widespread health effects, including increased risk of hypertension, diabetes, obesity, heart attack, and stroke. Moreover, sleep deprivation brings about vehicle accidents and medical errors and is therefore an urgent topic of investigation. During sleep deprivation, homeostatic and circadian processes interact to build up sleep pressure, which results in slow behavioral performance (cognitive lapses) typically attributed to attentional thalamic and frontoparietal circuits, but the underlying mechanisms remain unclear. Recently, through study of electroencephalograms (EEGs) in humans and local field potentials (LFPs) in nonhuman primates and rodents it was found that, during sleep deprivation, regional 'sleep-like' slow and theta (slow/theta) waves co-occur with impaired behavioral performance during wakefulness. Here we used intracranial electrodes to record single-neuron activities and LFPs in human neurosurgical patients performing a face/nonface categorization psychomotor vigilance task (PVT) over multiple experimental sessions, including a session after full-night sleep deprivation. We find that, just before cognitive lapses, the selective spiking responses of individual neurons in the medial temporal lobe (MTL) are attenuated, delayed, and lengthened. These 'neuronal lapses' are evident on a trial-by-trial basis when comparing the slowest behavioral PVT reaction times to the fastest. Furthermore, during cognitive lapses, LFPs exhibit a relative local increase in slow/theta activity that is correlated with degraded single-neuron responses and with baseline theta activity. Our results show that cognitive lapses involve local state-dependent changes in neuronal activity already present in the MTL.

  2. Serial agonistic attacks by greylag goose families, Anser anser, against the same opponent

    PubMed Central

    Scheiber, Isabella B.R.; Kotrschal, Kurt; Weiß, Brigitte M.

    2011-01-01

    It is known from primates that alliance partners may support each other’s interests in competition with others, for example, through repeated agonistic attacks against a particular individual. We examined serial aggressive interactions between greylag goose families and other flock members. We found that repeated attacks towards the same individual were common and that up to five serial attacks by family members followed an initial attack. Family size did not affect the frequency of such serial attacks. Juvenile geese evidently benefited most from active social support through serial attacks. About 60% of the juveniles’ lost primary interactions were subsequently reversed by another family member. This may be one of the reasons why juveniles rank higher in the social hierarchy than would be expected from their age and size alone. Losses in serial attacks predominantly occurred against other, presumably higher-ranking, family geese and ganders. We propose three major functions/consequences of serial attacks. Analogous to primates, serial attacks in greylag geese may serve to reinforce a losing experience of an opponent defeated in a preceding attack. On the side of the winning family, serial attacks may reinforce the experience of winning. Both winning and losing experiences are linked with physiological consequences in higher vertebrates, affecting the future social performance of winners or losers. Finally, serial attacks may signal the agonistic potential of a family to other flock members. This is supported by heart rate data, which indicate that greylags are competent to interpret third-party relationships. PMID:21984838

  3. The impact of anthelmintic treatment intervention on malaria infection and anaemia in school and preschool children in Magu district, Tanzania: an open label randomised intervention trial.

    PubMed

    Kinung'hi, Safari M; Magnussen, Pascal; Kishamawe, Coleman; Todd, Jim; Vennervald, Birgitte J

    2015-03-20

    Some studies have suggested that helminth infections increase the risk of malaria infection and are associated with increased number of malaria attacks and anaemia. Thus interventions to control helminth infections may have an impact on incidence of clinical malaria and anaemia. The current study assessed the impact of two anthelmintic treatment approaches on malaria infection and on anaemia in school and pre-school children in Magu district, Tanzania. A total of 765 children were enrolled into a prospective randomized anthelmintic intervention trial following a baseline study of 1546 children. Enrolled children were randomized to receive either repeated treatment with praziquantel and albendazole four times a year (intervention group, 394 children) or single dose treatment with praziquantel and albendazole once a year (control group, 371 children). Follow up examinations were conducted at 12 and 24 months after baseline to assess the impact of the intervention. Stool and urine samples were collected and examined for schistosome and soil transmitted helminth infections. Blood samples were also collected and examined for malaria parasites and haemoglobin concentrations. Monitoring of clinical malaria attacks was performed at each school during the two years of the intervention. Out of 1546 children screened for P. falciparum, S. mansoni, S. haematobium, hookworm and T. Trichiura at baseline, 1079 (69.8%) were infected with at least one of the four parasites. There was no significant difference in malaria infection (prevalence, parasite density and frequency of malaria attacks) and in the prevalence of anaemia between the repeated and single dose anthelmintic treatment groups at 12 and 24 months follow up (p>0.05). However, overall, there was significant improvement in mean haemoglobin concentrations (p<0.001) from baseline levels of 122.0 g/L and 123.0 g/L to 136.0 g/L and 136.8 g/L for the repeated and single dose treatment groups, respectively, at 24 months follow-up which resulted in significant reduction in prevalence of anaemia. These results suggest that repeated anthelmintic treatment did not have an impact on malaria infection compared to single dose treatment. However, both treatment approaches had overall impact in terms of improvements of haemoglobin levels and hence reductions in prevalence of anaemia.

  4. Laser beam propagation through a full scale aircraft turboprop engine exhaust

    NASA Astrophysics Data System (ADS)

    Henriksson, Markus; Gustafsson, Ove; Sjöqvist, Lars; Seiffer, Dirk; Wendelstein, Norbert

    2010-10-01

    The exhaust from engines introduces zones of extreme turbulence levels in local environments around aircraft. This may disturb the performance of aircraft mounted optical and laser systems. The turbulence distortion will be especially devastating for optical missile warning and laser based DIRCM systems used to protect manoeuvring aircraft against missile attacks, situations where the optical propagation path may come close to the engine exhaust. To study the extent of the turbulence zones caused by the engine exhaust and the strength of the effects on optical propagation through these zones a joint trial between Germany, the Netherlands, Sweden and the United Kingdom was performed using a medium sized military turboprop transport aircraft tethered to the ground at an airfield. This follows on earlier trials performed on a down-scaled jet-engine test rig. Laser beams were propagated along the axis of the aircraft at different distances relative to the engine exhaust and the spatial beam profiles and intensity scintillations were recorded with cameras and photodiodes. A second laser beam path was directed from underneath the loading ramp diagonally past one of the engines. The laser wavelengths used were 1.5 and 3.6 μm. In addition to spatial beam profile distortions temporal effects were investigated. Measurements were performed at different propeller speeds and at different distances from exhaust nozzle to the laser path. Significant increases in laser beam wander and long term beam radius were observed with the engine running. Corresponding increases were also registered in the scintillation index and the temporal fluctuations of the instantaneous power collected by the detector.

  5. Wounding patterns and human performance in knife attacks: optimising the protection provided by knife-resistant body armour.

    PubMed

    Bleetman, A; Watson, C H; Horsfall, I; Champion, S M

    2003-12-01

    Stab attacks generate high loads, and to defeat them, armour needs to be of a certain thickness and stiffness. Slash attacks produce much lower loads and armour designed to defeat them can be far lighter and more flexible. Phase 1: Human performance in slash attacks: 87 randomly selected students at the Royal Military College of Science were asked to make one slash attack with an instrumented blade on a vertically mounted target. No instructions on how to slash the target were given. The direction, contact forces and velocity of each attack were recorded. Phase 2: Clinical experience with edged weapon attacks: The location and severity of all penetrating injuries in patients attending the Glasgow Royal Infirmary between 1993 and 1996 were charted on anatomical figures. Phase 1: Two types of human slash behaviour were evident: a 'chop and drag' blow and a 'sweep motion' type of attack. 'Chop and drag' attacks had higher peak forces and velocities than sweep attacks. Shoulder to waist blows (diagonal) accounted for 82% of attacks, 71% of attackers used a long diagonal slash with an average cut length of 34 cm and 11% used short diagonal attacks with an average cut length of 25 cm. Only 18% of attackers slashed across the body (short horizontal); the average measured cut length of this type was 28 cm. The maximum peak force for the total sample population was 212 N; the maximum velocity was 14.88 m s(-1). The 95 percentile force for the total sample population was 181 N and the velocity was 9.89 m s(-1). Phase 2: 431 of the 500 patients had been wounded with edged weapons. The average number of wounds sustained by victims in knife assaults was 2.4. The distribution of wounds by frequency and severity are presented. Anti-slash protection is required for the arms, neck, shoulders, and thighs. The clinical experience of knife-attack victims provides information on the relative vulnerabilities of different regions of the body. It is anticipated that designing a tunic-type of Police uniform that is inherently stab and slash resistant will eventually replace the current obvious and often bulky extra protective vest. Attempts at making a combined garment will need to be guided by ergonomic considerations and field testing. A similar anatomical regional risk model might also be appropriate in the design of anti-ballistic armour and combined anti-ballistic and knife-resistant armour.

  6. Patent foramen ovale closure and migraine: science and sensibility.

    PubMed

    Gupta, Vinod Kumar

    2010-09-01

    Migraine has been associated with patent foramen ovale (PFO), and PFO closure has become the most high-profile nonpharmacologic invasive therapy recommended for the prevention of recurrent migraine attacks, as well as for preventing further attacks in cryptogenic stroke. The results of Migraine Intervention with STARFlex Technology (MIST), a controversial but important recent randomized clinical trial (RCT) of PFO closure for migraine, do not support PFO closure for preventing migraine attacks. All patients with migraine, however, do not have a PFO, and the characteristic periodicity and predictability of migraine cannot be explained on the basis of paradoxical embolism through the PFO. Closure of the PFO or atrial septal defect can aggravate migraine suddenly. PFO increases in size with age, but migraine generally subsides with the passage of years. Serendipity does play a role in some medical discoveries, but in the absence of a logically defensible theoretical basis, chance and statistics can both become misleading. With soft end points, RCTs in migraine patients can generate conflicting and irreconcilable data. RCTs cannot supplant or substitute clinical common sense or justify serendipity. Scientific progress mandates that any serendipitous research must ultimately conform to the principles of the basic sciences surrounding the chance discovery. PFO closure for preventing migraine attacks is an unfortunate, but sobering, chapter in the migraine research saga.

  7. Collective attacks and unconditional security in continuous variable quantum key distribution.

    PubMed

    Grosshans, Frédéric

    2005-01-21

    We present here an information theoretic study of Gaussian collective attacks on the continuous variable key distribution protocols based on Gaussian modulation of coherent states. These attacks, overlooked in previous security studies, give a finite advantage to the eavesdropper in the experimentally relevant lossy channel, but are not powerful enough to reduce the range of the reverse reconciliation protocols. Secret key rates are given for the ideal case where Bob performs optimal collective measurements, as well as for the realistic cases where he performs homodyne or heterodyne measurements. We also apply the generic security proof of Christiandl et al. to obtain unconditionally secure rates for these protocols.

  8. Using Discrete Event Simulation to Model Attacker Interactions with Cyber and Physical Security Systems

    DOE PAGES

    Perkins, Casey; Muller, George

    2015-10-08

    The number of connections between physical and cyber security systems is rapidly increasing due to centralized control from automated and remotely connected means. As the number of interfaces between systems continues to grow, the interactions and interdependencies between them cannot be ignored. Historically, physical and cyber vulnerability assessments have been performed independently. This independent evaluation omits important aspects of the integrated system, where the impacts resulting from malicious or opportunistic attacks are not easily known or understood. Here, we describe a discrete event simulation model that uses information about integrated physical and cyber security systems, attacker characteristics and simple responsemore » rules to identify key safeguards that limit an attacker's likelihood of success. Key features of the proposed model include comprehensive data generation to support a variety of sophisticated analyses, and full parameterization of safeguard performance characteristics and attacker behaviours to evaluate a range of scenarios. Lastly, we also describe the core data requirements and the network of networks that serves as the underlying simulation structure.« less

  9. The expert advantage in dynamic pattern recall persists across both attended and unattended display elements.

    PubMed

    Gorman, Adam D; Abernethy, Bruce; Farrow, Damian

    2013-07-01

    We examined how differences in attention influence how expert and novice basketball players encode into memory the specific structural information contained within patterns of play from their sport. Our participants were primed during a typical recall task to focus attention on either attacking or defending player formations before being asked to recall the attended or unattended portion of the pattern. Adherence to the instructional set was confirmed through an analysis of gaze distributions. Recall performance was superior for the experts relative to the novices across both the attended and unattended attacking and defensive pattern structures. Expert recall of attacker positions was unchanged with and without attention, whereas recall accuracy for the positions of defenders diminished without attention, as did the novices' recall of both attack and defense formations. The findings suggest that experienced performers are better than novices at encoding the elements from a complex and dynamic pattern in the absence of focused attention, with this advantage being especially evident in relation to the recall of attacking structure. Some revision of long-term memory theories of expertise will be necessary to accommodate these findings.

  10. Using Discrete Event Simulation to Model Attacker Interactions with Cyber and Physical Security Systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Perkins, Casey; Muller, George

    The number of connections between physical and cyber security systems is rapidly increasing due to centralized control from automated and remotely connected means. As the number of interfaces between systems continues to grow, the interactions and interdependencies between them cannot be ignored. Historically, physical and cyber vulnerability assessments have been performed independently. This independent evaluation omits important aspects of the integrated system, where the impacts resulting from malicious or opportunistic attacks are not easily known or understood. Here, we describe a discrete event simulation model that uses information about integrated physical and cyber security systems, attacker characteristics and simple responsemore » rules to identify key safeguards that limit an attacker's likelihood of success. Key features of the proposed model include comprehensive data generation to support a variety of sophisticated analyses, and full parameterization of safeguard performance characteristics and attacker behaviours to evaluate a range of scenarios. Lastly, we also describe the core data requirements and the network of networks that serves as the underlying simulation structure.« less

  11. Normobaric and hyperbaric oxygen therapy for the treatment and prevention of migraine and cluster headache.

    PubMed

    Bennett, Michael H; French, Christopher; Schnabel, Alexander; Wasiak, Jason; Kranke, Peter; Weibel, Stephanie

    2015-12-28

    Migraine and cluster headaches are severe and disabling. Migraine affects up to 18% of women, while cluster headaches are much less common (0.2% of the population). A number of acute and prophylactic therapies are available. Hyperbaric oxygen therapy (HBOT) is the therapeutic administration of 100% oxygen at environmental pressures greater than one atmosphere, while normobaric oxygen therapy (NBOT) is oxygen administered at one atmosphere. This is an updated version of the original Cochrane review published in Issue 3, 2008 under the title 'Normobaric and hyperbaric oxygen for migraine and cluster headache'. To examine the efficacy and safety of normobaric oxygen therapy (NBOT) and hyperbaric oxygen therapy (HBOT) in the treatment and prevention of migraine and cluster headache. We updated searches of the following databases up to 15 June 2015: CENTRAL (the Cochrane Library), MEDLINE, EMBASE, and CINAHL. For the original review we searched the following databases up to May 2008: CENTRAL, MEDLINE, EMBASE, CINAHL, DORCTIHM, and reference lists from relevant articles. We handsearched relevant journals and contacted researchers to identify trials. Randomised controlled trials comparing HBOT or NBOT with one another, other active therapies, placebo (sham) interventions, or no treatment in participants with migraine or cluster headache. Three review authors independently extracted data and assessed the quality of the evidence using the GRADE approach. In this update, we included 11 trials with 209 participants. Five trials (103 participants) compared HBOT versus sham therapy for acute migraine, three trials compared NBOT to sham therapy or ergotamine tartrate for cluster headache (145 participants), two trials evaluated HBOT for cluster headache (29 participants), and one trial (56 participants) compared NBOT to sham for a mixed group of headache. The risk of bias varied considerably across these trials but in general trial quality was poor to moderate. One trial may not have been truly randomised and two included studies were reported as abstracts only. Seven trials did not indicate allocation concealment or randomisation method. Notably, 10 of the 11 trials used a sham comparator therapy and masked the outcome assessor to allocation.We pooled data from three trials, which suggested that HBOT was effective in relieving migraine headaches compared to sham therapy (risk ratio (RR) 6.21, 95% CI 2.41 to 16.00; 58 participants, three trials). The quality of evidence was low, having been downgraded for small crossover studies with incomplete reporting. There was no evidence that HBOT could prevent migraine episodes, reduce the incidence of nausea and vomiting, or reduce the requirement for rescue medication. There was no evidence that HBOT was effective for the termination of cluster headache (RR 11.38, 95% CI 0.77 to 167.85; P = 0.08) (one trial), but this trial had low power.NBOT was effective in terminating cluster headache compared to sham in a single small study (RR 7.88, 95% CI 1.13 to 54.66), but not superior to ergotamine administration in another small trial (RR 1.17, 95% CI 0.94 to 1.46; P = 0.16). A third trial reported a statistically significant difference in the proportion of attacks successfully treated with oxygen (117 of 150 attacks were successfully treated with NBOT (78%) versus 30 of 148 attacks treated with NBOT (20%)). The proportion of responders was consistent across these three trials, and suggested more than 75% of headaches were likely to respond to NBOT.No serious adverse events during HBOT or NBOT were reported. Since the last version of this review, two new included studies have provided additional information to change the conclusions. There was some evidence that HBOT was effective for the termination of acute migraine in an unselected population, and some evidence that NBOT was similarly effective in cluster headache. Given the cost and poor availability of HBOT, more research should be done on patients unresponsive to standard therapy. NBOT is cheap, safe, and easy to apply, so will probably continue to be used despite the limited evidence in this review.

  12. Evaluation of avoralstat, an oral kallikrein inhibitor, in a Phase 3 hereditary angioedema prophylaxis trial: the OPUS-2 study.

    PubMed

    Riedl, Marc A; Aygören-Pürsün, Emel; Baker, James; Farkas, Henriette; Anderson, John; Bernstein, Jonathan A; Bouillet, Laurence; Busse, Paula; Manning, Michael; Magerl, Markus; Gompels, Mark; Huissoon, Aarnoud P; Longhurst, Hillary; Lumry, William; Ritchie, Bruce; Shapiro, Ralph; Soteres, Daniel; Banerji, Aleena; Cancian, Mauro; Johnston, Douglas T; Craig, Timothy J; Launay, David; Li, H Henry; Liebhaber, Myron; Nickel, Timothy; Offenberger, Jacob; Rae, William; Schrijvers, Rik; Triggiani, Massimo; Wedner, H James; Dobo, Sylvia; Cornpropst, Melanie; Clemons, Desiree; Fang, Lei; Collis, Phil; Sheridan, William P; Maurer, Marcus

    2018-04-24

    Effective inhibition of plasma kallikrein may have significant benefits for patients with hereditary angioedema due to deficiency of C1 inhibitor (C1-INH-HAE) by reducing the frequency of angioedema attacks. Avoralstat is a small molecule inhibitor of plasma kallikrein. This study (OPuS-2) evaluated the efficacy and safety of prophylactic avoralstat 300 or 500 mg compared with placebo. OPuS-2 was a Phase 3, multicenter, randomized, double-blind, placebo-controlled, parallel-group study. Subjects were administered avoralstat 300 mg, avoralstat 500 mg, or placebo orally 3 times per day for 12 weeks. The primary efficacy endpoint was the angioedema attack rate based on adjudicator-confirmed attacks. A total of 110 subjects were randomized and dosed. The least squares (LS) mean attack rates per week were 0.589, 0.675, and 0.593 for subjects receiving avoralstat 500 mg, avoralstat 300 mg, and placebo, respectively. Overall, 1 subject in each of the avoralstat groups and no subjects in the placebo group were attack-free during the 84-day treatment period. The LS mean duration of all confirmed attacks was 25.4, 29.4 and 31.4 hours for the avoralstat 500 mg, avoralstat 300 mg and placebo groups respectively. Using the Angioedema Quality of Life Questionnaire (AE-QoL), improved QoL was observed for the avoralstat 500 mg group compared with placebo. Avoralstat was generally safe and well tolerated. Although this study did not demonstrate efficacy of avoralstat in preventing angioedema attacks in C1-INH-HAE, it provided evidence of shortened angioedema episodes and improved QoL in the avoralstat 500 mg treatment group compared with placebo. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  13. Analysis of metro network performance from a complex network perspective

    NASA Astrophysics Data System (ADS)

    Wu, Xingtang; Dong, Hairong; Tse, Chi Kong; Ho, Ivan W. H.; Lau, Francis C. M.

    2018-02-01

    In this paper, the performance of metro networks is studied from a network science perspective. We review the structural efficiency of metro networks on the basis of a passenger's intuitive routing strategy that optimizes the number of transfers and the distance traveled.A new node centrality measure, called node occupying probability, is introduced for evaluating the level of utilization of stations. The robustness of a metro network is analyzed under several attack scenarios. Six metro networks (Beijing, London, Paris, Hong Kong, Tokyo and New York) are compared in terms of the node occupying probability and a few other performance parameters. Simulation results show that the New York metro system has better topological efficiency, the Tokyo and Hong Kong systems are the most robust under random attack and target attack, respectively.

  14. Efficacy and safety of ticagrelor versus aspirin in acute stroke or transient ischaemic attack of atherosclerotic origin: a subgroup analysis of SOCRATES, a randomised, double-blind, controlled trial.

    PubMed

    Amarenco, Pierre; Albers, Gregory W; Denison, Hans; Easton, J Donald; Evans, Scott R; Held, Peter; Hill, Michael D; Jonasson, Jenny; Kasner, Scott E; Ladenvall, Per; Minematsu, Kazuo; Molina, Carlos A; Wang, Yongjun; Wong, K S Lawrence; Johnston, S Claiborne

    2017-04-01

    Ticagrelor is an effective antiplatelet therapy for patients with coronary atherosclerotic disease and might be more effective than aspirin in preventing recurrent stroke and cardiovascular events in patients with acute cerebral ischaemia of atherosclerotic origin. Our aim was to test for a treatment-by-ipsilateral atherosclerotic stenosis interaction in a subgroup analysis of patients in the Acute Stroke or Transient Ischaemic Attack Treated with Aspirin or Ticagrelor and Patient Outcomes (SOCRATES) trial. SOCRATES was a randomised, double-blind, controlled trial of ticagrelor versus aspirin in patients aged 40 years or older with a non-cardioembolic, non-severe acute ischaemic stroke, or high-risk transient ischaemic attack from 674 hospitals in 33 countries. We randomly allocated patients (1:1) to ticagrelor (180 mg loading dose on day 1 followed by 90 mg twice daily for days 2-90, given orally) or aspirin (300 mg on day 1 followed by 100 mg daily for days 2-90, given orally) within 24 h of symptom onset. Investigators classified all patients into atherosclerotic and non-atherosclerotic groups for the prespecified, exploratory analysis reported in this study. The primary endpoint was the time to occurrence of stroke, myocardial infarction, or death within 90 days. Efficacy analysis was by intention to treat. The SOCRATES trial is registered with ClinicalTrials.gov, number NCT01994720. Between Jan 7, 2014, and Oct 29, 2015, we randomly allocated 13 199 patients (6589 [50%] to ticagrelor and 6610 [50%] to aspirin). Potentially symptomatic ipsilateral atherosclerotic stenosis was reported in 3081 (23%) of 13 199 patients. We found a treatment-by-atherosclerotic stenosis interaction (p=0·017). 103 (6·7%) of 1542 patients with ipsilateral stenosis in the ticagrelor group and 147 (9·6%) of 1539 patients with ipsilateral stenosis in the aspirin group had an occurrence of stroke, myocardial infarction, or death within 90 days (hazard ratio 0·68 [95% CI 0·53-0·88]; p=0·003). In 10 118 patients with no ipsilateral stenosis, 339 (6·7%) of 5047 patients in the ticagrelor group had an occurrence of stroke, myocardial infarction, or death within 90 days compared with 350 (6·9%) of 5071 in the aspirin group (0·97 [0·84-1·13]; p=0·72). There were no significant differences in the proportion of life-threatening bleeding or major or minor bleeding events in patients with ipsilateral stenosis in the ticagrelor group compared with the aspirin group. In this prespecified exploratory analysis, ticagrelor was superior to aspirin at preventing stroke, myocardial infarction, or death at 90 days in patients with acute ischaemic stroke or transient ischaemic attack when associated with ipsilateral atherosclerotic stenosis. An understanding of stroke mechanisms and causes is important to deliver safe and efficacious treatments for early stroke prevention. AstraZeneca. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Sequential defense against random and intentional attacks in complex networks.

    PubMed

    Chen, Pin-Yu; Cheng, Shin-Ming

    2015-02-01

    Network robustness against attacks is one of the most fundamental researches in network science as it is closely associated with the reliability and functionality of various networking paradigms. However, despite the study on intrinsic topological vulnerabilities to node removals, little is known on the network robustness when network defense mechanisms are implemented, especially for networked engineering systems equipped with detection capabilities. In this paper, a sequential defense mechanism is first proposed in complex networks for attack inference and vulnerability assessment, where the data fusion center sequentially infers the presence of an attack based on the binary attack status reported from the nodes in the network. The network robustness is evaluated in terms of the ability to identify the attack prior to network disruption under two major attack schemes, i.e., random and intentional attacks. We provide a parametric plug-in model for performance evaluation on the proposed mechanism and validate its effectiveness and reliability via canonical complex network models and real-world large-scale network topology. The results show that the sequential defense mechanism greatly improves the network robustness and mitigates the possibility of network disruption by acquiring limited attack status information from a small subset of nodes in the network.

  16. Hereditary Angioedema Attacks Resolve Faster and Are Shorter after Early Icatibant Treatment

    PubMed Central

    Maurer, Marcus; Kaplan, Allen; Investigators, on behalf of I. O. S.

    2013-01-01

    Background Attacks of hereditary angioedema (HAE) are unpredictable and, if affecting the upper airway, can be lethal. Icatibant is used for physician- or patient self-administered symptomatic treatment of HAE attacks in adults. Its mode of action includes disruption of the bradykinin pathway via blockade of the bradykinin B2 receptor. Early treatment is believed to shorten attack duration and prevent severe outcomes; however, evidence to support these benefits is lacking. Objective To examine the impact of timing of icatibant administration on the duration and resolution of HAE type I and II attacks. Methods The Icatibant Outcome Survey is an international, prospective, observational study for patients treated with icatibant. Data on timings and outcomes of icatibant treatment for HAE attacks were collected between July 2009–February 2012. A mixed-model of repeated measures was performed for 426 attacks in 136 HAE type I and II patients. Results Attack duration was significantly shorter in patients treated <1 hour of attack onset compared with those treated ≥1 hour (6.1 hours versus 16.8 hours [p<0.001]). Similar significant effects were observed for <2 hours versus ≥2 hours (7.2 hours versus 20.2 hours [p<0.001]) and <5 hours versus ≥5 hours (8.0 hours versus 23.5 hours [p<0.001]). Treatment within 1 hour of attack onset also significantly reduced time to attack resolution (5.8 hours versus 8.8 hours [p<0.05]). Self-administrators were more likely to treat early and experience shorter attacks than those treated by a healthcare professional. Conclusion Early blockade of the bradykinin B2 receptor with icatibant, particularly within the first hour of attack onset, significantly reduced attack duration and time to attack resolution. PMID:23390491

  17. Risk-based decision making for staggered bioterrorist attacks : resource allocation and risk reduction in "reload" scenarios.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lemaster, Michelle Nicole; Gay, David M.; Ehlen, Mark Andrew

    2009-10-01

    Staggered bioterrorist attacks with aerosolized pathogens on population centers present a formidable challenge to resource allocation and response planning. The response and planning will commence immediately after the detection of the first attack and with no or little information of the second attack. In this report, we outline a method by which resource allocation may be performed. It involves probabilistic reconstruction of the bioterrorist attack from partial observations of the outbreak, followed by an optimization-under-uncertainty approach to perform resource allocations. We consider both single-site and time-staggered multi-site attacks (i.e., a reload scenario) under conditions when resources (personnel and equipment whichmore » are difficult to gather and transport) are insufficient. Both communicable (plague) and non-communicable diseases (anthrax) are addressed, and we also consider cases when the data, the time-series of people reporting with symptoms, are confounded with a reporting delay. We demonstrate how our approach develops allocations profiles that have the potential to reduce the probability of an extremely adverse outcome in exchange for a more certain, but less adverse outcome. We explore the effect of placing limits on daily allocations. Further, since our method is data-driven, the resource allocation progressively improves as more data becomes available.« less

  18. Development of a Flush Airdata Sensing System on a Sharp-Nosed Vehicle for Flight at Mach 3 to 8

    NASA Technical Reports Server (NTRS)

    Davis, Mark C.; Pahle, Joseph W.; White, John Terry; Marshall, Laurie A.; Mashburn, Michael J.; Franks, Rick

    2000-01-01

    NASA Dryden Flight Research Center has developed a flush airdata sensing (FADS) system on a sharp-nosed, wedge-shaped vehicle. This paper details the design and calibration of a real-time angle-of-attack estimation scheme developed to meet the onboard airdata measurement requirements for a research vehicle equipped with a supersonic-combustion ramjet engine. The FADS system has been designed to perform in flights at Mach 3-8 and at -6 deg - 12 deg angle of attack. The description of the FADS architecture includes port layout, pneumatic design, and hardware integration. Predictive models of static and dynamic performance are compared with wind-tunnel results across the Mach and angle-of-attack range. Results indicate that static angle-of-attack accuracy and pneumatic lag can be adequately characterized and incorporated into a real-time algorithm.

  19. Practical, Real-Time, and Robust Watermarking on the Spatial Domain for High-Definition Video Contents

    NASA Astrophysics Data System (ADS)

    Kim, Kyung-Su; Lee, Hae-Yeoun; Im, Dong-Hyuck; Lee, Heung-Kyu

    Commercial markets employ digital right management (DRM) systems to protect valuable high-definition (HD) quality videos. DRM system uses watermarking to provide copyright protection and ownership authentication of multimedia contents. We propose a real-time video watermarking scheme for HD video in the uncompressed domain. Especially, our approach is in aspect of practical perspectives to satisfy perceptual quality, real-time processing, and robustness requirements. We simplify and optimize human visual system mask for real-time performance and also apply dithering technique for invisibility. Extensive experiments are performed to prove that the proposed scheme satisfies the invisibility, real-time processing, and robustness requirements against video processing attacks. We concentrate upon video processing attacks that commonly occur in HD quality videos to display on portable devices. These attacks include not only scaling and low bit-rate encoding, but also malicious attacks such as format conversion and frame rate change.

  20. Investigation of High-alpha Lateral-directional Control Power Requirements for High-performance Aircraft

    NASA Technical Reports Server (NTRS)

    Foster, John V.; Ross, Holly M.; Ashley, Patrick A.

    1993-01-01

    Designers of the next-generation fighter and attack airplanes are faced with the requirements of good high-angle-of-attack maneuverability as well as efficient high speed cruise capability with low radar cross section (RCS) characteristics. As a result, they are challenged with the task of making critical design trades to achieve the desired levels of maneuverability and performance. This task has highlighted the need for comprehensive, flight-validated lateral-directional control power design guidelines for high angles of attack. A joint NASA/U.S. Navy study has been initiated to address this need and to investigate the complex flight dynamics characteristics and controls requirements for high-angle-of-attack lateral-directional maneuvering. A multi-year research program is underway which includes ground-based piloted simulation and flight validation. This paper will give a status update of this program that will include a program overview, description of test methodology and preliminary results.

  1. Investigation of high-alpha lateral-directional control power requirements for high-performance aircraft

    NASA Technical Reports Server (NTRS)

    Foster, John V.; Ross, Holly M.; Ashley, Patrick A.

    1993-01-01

    Designers of the next-generation fighter and attack airplanes are faced with the requirements of good high angle-of-attack maneuverability as well as efficient high speed cruise capability with low radar cross section (RCS) characteristics. As a result, they are challenged with the task of making critical design trades to achieve the desired levels of maneuverability and performance. This task has highlighted the need for comprehensive, flight-validated lateral-directional control power design guidelines for high angles of attack. A joint NASA/U.S. Navy study has been initiated to address this need and to investigate the complex flight dynamics characteristics and controls requirements for high angle-of-attack lateral-directional maneuvering. A multi-year research program is underway which includes groundbased piloted simulation and flight validation. This paper will give a status update of this program that will include a program overview, description of test methodology and preliminary results.

  2. Development of a Flush Airdata Sensing System on a Sharp-Nosed Vehicle for Flight at Mach 3 to 8

    NASA Technical Reports Server (NTRS)

    Davis, Mark C.; Pahle, Joseph W.; White, John Terry; Marshall, Laurie A.; Mashburn, Michael J.; Franks, Rick

    2000-01-01

    NASA Dryden Flight Research Center has developed a flush airdata sensing (FADS) system on a sharp-nosed, wedge-shaped vehicle. This paper details the design and calibration of a real-time angle-of-attack estimation scheme developed to meet the onboard airdata measurement requirements for a research vehicle equipped with a supersonic-combustion ramjet engine. The FADS system has been designed to perform in flights at speeds between Mach 3 and Mach 8 and at angles of attack between -6 deg. and 12 deg. The description of the FADS architecture includes port layout, pneumatic design, and hardware integration. Predictive models of static and dynamic performance are compared with wind-tunnel results across the Mach and angle-of-attack range. Results indicate that static angle-of-attack accuracy and pneumatic lag can be adequately characterized and incorporated into a real-time algorithm.

  3. BFT replication resistant to MAC attacks

    NASA Astrophysics Data System (ADS)

    Zbierski, Maciej

    2016-09-01

    Over the last decade numerous Byzantine fault-tolerant (BFT) replication protocols have been proposed in the literature. However, the vast majority of these solutions reuse the same authentication scheme, which makes them susceptible to a so called MAC attack. Such vulnerability enables malicious clients to undetectably prevent the replicated service from processing incoming client requests, and consequently making it permanently unavailable. While some BFT protocols attempted to address this issue by using different authentication mechanisms, they at the same time significantly degraded the performance achieved in correct environments. This article presents a novel adaptive authentication mechanism which can be combined with practically any Byzantine fault-tolerant replication protocol. Unlike previous solutions, the proposed scheme dynamically switches between two operation modes to combine high performance in correct environments and liveness during MAC attacks. The experiment results presented in the article demonstrate that the proposed mechanism can sufficiently tolerate MAC attacks without introducing any observable overhead whenever no faults are present.

  4. On resilience studies of system detection and recovery techniques against stealthy insider attacks

    NASA Astrophysics Data System (ADS)

    Wei, Sixiao; Zhang, Hanlin; Chen, Genshe; Shen, Dan; Yu, Wei; Pham, Khanh D.; Blasch, Erik P.; Cruz, Jose B.

    2016-05-01

    With the explosive growth of network technologies, insider attacks have become a major concern to business operations that largely rely on computer networks. To better detect insider attacks that marginally manipulate network traffic over time, and to recover the system from attacks, in this paper we implement a temporal-based detection scheme using the sequential hypothesis testing technique. Two hypothetical states are considered: the null hypothesis that the collected information is from benign historical traffic and the alternative hypothesis that the network is under attack. The objective of such a detection scheme is to recognize the change within the shortest time by comparing the two defined hypotheses. In addition, once the attack is detected, a server migration-based system recovery scheme can be triggered to recover the system to the state prior to the attack. To understand mitigation of insider attacks, a multi-functional web display of the detection analysis was developed for real-time analytic. Experiments using real-world traffic traces evaluate the effectiveness of Detection System and Recovery (DeSyAR) scheme. The evaluation data validates the detection scheme based on sequential hypothesis testing and the server migration-based system recovery scheme can perform well in effectively detecting insider attacks and recovering the system under attack.

  5. Electrocortical and behavioral responses elicited by acute electrical stimulation of inferior thalamic peduncle and nucleus reticularis thalami in a patient with major depression disorder.

    PubMed

    Velasco, Marcos; Velasco, Francisco; Jiménez, Fiacro; Carrillo-Ruiz, José D; Velasco, Ana Luisa; Salín-Pascual, Rafael

    2006-02-01

    Our aim was to study electrocortical and behavioral responses elicited by 6, 60 and 3/s stimulation of the inferior thalamic peduncle (ITP) and nucleus reticularis thalami (Re) in a patient with of major depression disorder resistant to psychotherapy, pharmacotherapy and electroconvulsive therapy and candidate to be treated by electrical stimulation of the ITP. In this patient, two multicontact electrodes were implanted bilaterally through frontal coronal parasagittal burr-holes with oblique trajectories aiming ITP and Re. Stimulation was performed through externalized systems. Referential scalp electroencephalographic (EEG) recordings were performed and subjective sensations and clinical symptoms reported by patient and changes in responsiveness in single response tasks during stimulation trials were systematically recorded. Unilateral, low (6/s) and high (60/s) frequency stimulation of either ITP or Re produced identical recruiting-like responses or desynchronization-DC shift changes predominant at frontopolar region, bilaterally. Billateral, high intensity 3/s stimulation or either ITP or Re produced electrocortical responses that consisted in generalized 3/s spike-wave complexes predominant at frontopolar, frontocentral and frontotemporal regions. However, while ITP responses were accompanied by all symptoms described for a spontaneous absence attack, Re responses were behaviorly accompanied only by delayed reaction time. These data suggests that in humans as in cats, ITP and Re are both part of a non-specific thalamo-orbitofrontal system normally engaged in cortical synchronization, selective attention and sleep. Under abnormal conditions, ITP and RE may play a role in the physiopathology of typical absence attacks and depression disorders.

  6. [A survey of perioperative asthmatic attack among patients with bronchial asthma underwent general anesthesia].

    PubMed

    Ie, Kenya; Yoshizawa, Atsuto; Hirano, Satoru; Izumi, Sinyuu; Hojo, Masaaki; Sugiyama, Haruhito; Kobayasi, Nobuyuki; Kudou, Kouichirou; Maehara, Yasuhiro; Kawachi, Masaharu; Miyakoshi, Kouichi

    2010-07-01

    We investigated the risk factor of perioperative asthmatic attack and effectiveness of preventing treatment for asthmatic attack before operation. We performed retrospective chart review of one hundred eleven patients with asthma underwent general anesthesia and surgical intervention from January 2006 to October 2007 in our hospital. The rate of perioperative asthmatic attack were as follows; 10.2% (5 in 49 cases) in no pretreatment group, 7.5% (3 in 40 cases) in any pretreatments except for systemic steroid, and 4.5% (1 in 22 cases) in systemic steroid pretreatment group. Neither preoperative asthma severity nor duration from the last attack had significant relevancy to perioperative attack rate. The otolaryngological surgery, especially those have nasal polyp and oral surgery had high perioperative asthma attack rate, although there was no significant difference. We recommend the systemic steroid pretreatment for asthmatic patients, especially when they have known risk factor such as administration of the systemic steroid within 6 months, or possibly new risk factor such as nasal polyp, otolaryngological and oral surgery.

  7. Decision Aids for Airborne Intercept Operations in Advanced Aircrafts

    NASA Technical Reports Server (NTRS)

    Madni, A.; Freedy, A.

    1981-01-01

    A tactical decision aid (TDA) for the F-14 aircrew, i.e., the naval flight officer and pilot, in conducting a multitarget attack during the performance of a Combat Air Patrol (CAP) role is presented. The TDA employs hierarchical multiattribute utility models for characterizing mission objectives in operationally measurable terms, rule based AI-models for tactical posture selection, and fast time simulation for maneuver consequence prediction. The TDA makes aspect maneuver recommendations, selects and displays the optimum mission posture, evaluates attackable and potentially attackable subsets, and recommends the 'best' attackable subset along with the required course perturbation.

  8. A quantum optical firewall based on simple quantum devices

    NASA Astrophysics Data System (ADS)

    Amellal, H.; Meslouhi, A.; Hassouni, Y.; El Baz, M.

    2015-07-01

    In order to enhance the transmission security in quantum communications via coherent states, we propose a quantum optical firewall device to protect a quantum cryptosystem against eavesdropping through optical attack strategies. Similar to the classical model of the firewall, the proposed device gives legitimate users the possibility of filtering, controlling (input/output states) and making a decision (access or deny) concerning the traveling states. To prove the security and efficiency of the suggested optical firewall, we analyze its performances against the family of intercept and resend attacks, especially against one of the most prominent attack schemes known as "Faked State Attack."

  9. Using the Domain Name System to Thwart Automated Client-Based Attacks

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Taylor, Curtis R; Shue, Craig A

    2011-09-01

    On the Internet, attackers can compromise systems owned by other people and then use these systems to launch attacks automatically. When attacks such as phishing or SQL injections are successful, they can have negative consequences including server downtime and the loss of sensitive information. Current methods to prevent such attacks are limited in that they are application-specific, or fail to block attackers. Phishing attempts can be stopped with email filters, but if the attacker manages to successfully bypass these filters, then the user must determine if the email is legitimate or not. Unfortunately, they often are unable to do so.more » Since attackers have a low success rate, they attempt to compensate for it in volume. In order to have this high throughput, attackers take shortcuts and break protocols. We use this knowledge to address these issues by implementing a system that can detect malicious activity and use it to block attacks. If the client fails to follow proper procedure, they can be classified as an attacker. Once an attacker has been discovered, they will be isolated and monitored. This can be accomplished using existing software in Ubuntu Linux applications, along with our custom wrapper application. After running the system and seeing its performance on three popular Web browsers Chromium, Firefox and Internet Explorer as well as two popular email clients, Thunderbird and Evolution, we found that not only is this system conceivable, it is effective and has low overhead.« less

  10. Incidence and impact of dog attacks on guide dogs in the UK.

    PubMed

    Brooks, A; Moxon, R; England, G C W

    2010-06-19

    In a retrospective survey, researchers identified 100 incidents of attacks on guide dogs by other dogs. These were reviewed in order to determine the number, severity and impact on the handler and dog, and the characteristics of the aggressors and victims. During the study period there were more than three attacks reported each month, with 61 per cent of the attacks being upon dogs that were in harness and working with an owner or trainer. The majority of the dogs that were attacked were male (62 per cent), and the breeds that were over-represented (relative to their prevalence in the general guide dog population) were the labrador and the golden retriever x flat-coated retriever crossbreed. Most of the attacks occurred in public places between 09.00 and 15.00 and the majority (61 per cent) of the attacking dogs were off the lead at the time of the attack. Thirty-eight per cent of the attacking dogs were of bull breeds, which were over-represented among attackers compared with the proportion of this breed type in the general dog population. Veterinary attention was sought after 41 per cent of the attacks, and in 19 per cent of instances there was injury to the handler or to a member of the public. The attacks were reported to have affected the working performance and behaviour of the victim dog in 45 per cent of the instances, and two dogs had to be subsequently withdrawn from working as guide dogs.

  11. Develop a solution for protecting and securing enterprise networks from malicious attacks

    NASA Astrophysics Data System (ADS)

    Kamuru, Harshitha; Nijim, Mais

    2014-05-01

    In the world of computer and network security, there are myriad ways to launch an attack, which, from the perspective of a network, can usually be defined as "traffic that has huge malicious intent." Firewall acts as one of the measure in order to secure the device from incoming unauthorized data. There are infinite number of computer attacks that no firewall can prevent, such as those executed locally on the machine by a malicious user. From the network's perspective, there are numerous types of attack. All the attacks that degrade the effectiveness of data can be grouped into two types: brute force and precision. The Firewall that belongs to Juniper has the capability to protect against both types of attack. Denial of Service (DoS) attacks are one of the most well-known network security threats under brute force attacks, which is largely due to the high-profile way in which they can affect networks. Over the years, some of the largest, most respected Internet sites have been effectively taken offline by Denial of Service (DOS) attacks. A DoS attack typically has a singular focus, namely, to cause the services running on a particular host or network to become unavailable. Some DoS attacks exploit vulnerabilities in an operating system and cause it to crash, such as the infamous Win nuke attack. Others submerge a network or device with traffic so that there are no more resources to handle legitimate traffic. Precision attacks typically involve multiple phases and often involves a bit more thought than brute force attacks, all the way from reconnaissance to machine ownership. Before a precision attack is launched, information about the victim needs to be gathered. This information gathering typically takes the form of various types of scans to determine available hosts, networks, and ports. The hosts available on a network can be determined by ping sweeps. The available ports on a machine can be located by port scans. Screens cover a wide variety of attack traffic as they are configured on a per-zone basis. Depending on the type of screen being configured, there may be additional settings beyond simply blocking the traffic. Attack prevention is also a native function of any firewall. Juniper Firewall handles traffic on a per-flow basis. We can use flows or sessions as a way to determine whether traffic attempting to traverse the firewall is legitimate. We control the state-checking components resident in Juniper Firewall by configuring "flow" settings. These settings allow you to configure state checking for various conditions on the device. You can use flow settings to protect against TCP hijacking, and to generally ensure that the fire-wall is performing full state processing when desired. We take a case study of attack on a network and perform study of the detection of the malicious packets on a Net screen Firewall. A new solution for securing enterprise networks will be developed here.

  12. Anti-spoofing for display and print attacks on palmprint verification systems

    NASA Astrophysics Data System (ADS)

    Kanhangad, Vivek; Bhilare, Shruti; Garg, Pragalbh; Singh, Pranjalya; Chaudhari, Narendra

    2015-05-01

    A number of approaches for personal authentication using palmprint features have been proposed in the literature, majority of which focus on improving the matching performance. However, of late, preventing potential attacks on biometric systems has become a major concern as more and more biometric systems get deployed for wide range of applications. Among various types of attacks, sensor level attack, commonly known as spoof attack, has emerged as the most common attack due to simplicity in its execution. In this paper, we present an approach for detection of display and print based spoof attacks on palmprint verifcation systems. The approach is based on the analysis of acquired hand images for estimating surface re ectance. First and higher order statistical features computed from the distributions of pixel intensities and sub-band wavelet coeefficients form the feature set. A trained binary classifier utilizes the discriminating information to determine if the acquired image is of real hand or a fake one. Experiments are performed on a publicly available hand image dataset, containing 1300 images corresponding to 230 subjects. Experimental results show that the real hand biometrics samples can be substituted by the fake digital or print copies with an alarming spoof acceptance rate as high as 79.8%. Experimental results also show that the proposed spoof detection approach is very effective for discriminating between real and fake palmprint images. The proposed approach consistently achieves over 99% average 10-fold cross validation classification accuracy in our experiments.

  13. Large-scale wind-tunnel investigation of a close-coupled canard-delta-wing fighter model through high angles of attack

    NASA Technical Reports Server (NTRS)

    Stoll, F.; Koenig, D. G.

    1983-01-01

    Data obtained through very high angles of attack from a large-scale, subsonic wind-tunnel test of a close-coupled canard-delta-wing fighter model are analyzed. The canard delays wing leading-edge vortex breakdown, even for angles of attack at which the canard is completely stalled. A vortex-lattice method was applied which gave good predictions of lift and pitching moment up to an angle of attack of about 20 deg, where vortex-breakdown effects on performance become significant. Pitch-control inputs generally retain full effectiveness up to the angle of attack of maximum lift, beyond which, effectiveness drops off rapidly. A high-angle-of-attack prediction method gives good estimates of lift and drag for the completely stalled aircraft. Roll asymmetry observed at zero sideslip is apparently caused by an asymmetry in the model support structure.

  14. Mortality and morbidity during and after Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial: results by sex.

    PubMed

    Oparil, Suzanne; Davis, Barry R; Cushman, William C; Ford, Charles E; Furberg, Curt D; Habib, Gabriel B; Haywood, L Julian; Margolis, Karen; Probstfield, Jeffrey L; Whelton, Paul K; Wright, Jackson T

    2013-05-01

    To determine whether an angiotensin-converting enzyme inhibitor (lisinopril) or calcium channel blocker (amlodipine) is superior to a diuretic (chlorthalidone) in reducing cardiovascular disease incidence in sex subgroups, we carried out a prespecified subgroup analysis of 15 638 women and 17 719 men in the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT). Total follow-up (active treatment + passive surveillance using national administrative databases to ascertain deaths and hospitalizations) was 8 to 13 years. The primary outcome was fatal coronary heart disease or nonfatal myocardial infarction. Secondary outcomes included all-cause mortality, stroke, combined cardiovascular disease (coronary heart disease death, nonfatal myocardial infarction, stroke, angina, coronary revascularization, heart failure [HF], or peripheral vascular disease), and end-stage renal disease. In-trial rates of HF, stroke, and combined cardiovascular disease were significantly higher for lisinopril compared with chlorthalidone, and rates of HF were significantly higher for amlodipine compared with chlorthalidone in both men and women. There were no significant treatment sex interactions. These findings did not persist through the extension period with the exception of the HF result for amlodipine versus chlorthalidone, which did not differ significantly by sex. For both women and men, rates were not lower in the amlodipine or lisinopril groups than in the chlorthalidone group for either the primary coronary heart disease outcome or any other cardiovascular disease outcome, and chlorthalidone-based treatment resulted in the lowest risk of HF. Neither lisinopril nor amlodipine is superior to chlorthalidone for initial treatment of hypertension in either women or men. Clinical Trial Registration- clinicaltrials.gov; Identifier: NCT00000542.

  15. Heterogeneity in Early Responses in ALLHAT (Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial).

    PubMed

    Dhruva, Sanket S; Huang, Chenxi; Spatz, Erica S; Coppi, Andreas C; Warner, Frederick; Li, Shu-Xia; Lin, Haiqun; Xu, Xiao; Furberg, Curt D; Davis, Barry R; Pressel, Sara L; Coifman, Ronald R; Krumholz, Harlan M

    2017-07-01

    Randomized trials of hypertension have seldom examined heterogeneity in response to treatments over time and the implications for cardiovascular outcomes. Understanding this heterogeneity, however, is a necessary step toward personalizing antihypertensive therapy. We applied trajectory-based modeling to data on 39 763 study participants of the ALLHAT (Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial) to identify distinct patterns of systolic blood pressure (SBP) response to randomized medications during the first 6 months of the trial. Two trajectory patterns were identified: immediate responders (85.5%), on average, had a decreasing SBP, whereas nonimmediate responders (14.5%), on average, had an initially increasing SBP followed by a decrease. Compared with those randomized to chlorthalidone, participants randomized to amlodipine (odds ratio, 1.20; 95% confidence interval [CI], 1.10-1.31), lisinopril (odds ratio, 1.88; 95% CI, 1.73-2.03), and doxazosin (odds ratio, 1.65; 95% CI, 1.52-1.78) had higher adjusted odds ratios associated with being a nonimmediate responder (versus immediate responder). After multivariable adjustment, nonimmediate responders had a higher hazard ratio of stroke (hazard ratio, 1.49; 95% CI, 1.21-1.84), combined cardiovascular disease (hazard ratio, 1.21; 95% CI, 1.11-1.31), and heart failure (hazard ratio, 1.48; 95% CI, 1.24-1.78) during follow-up between 6 months and 2 years. The SBP response trajectories provided superior discrimination for predicting downstream adverse cardiovascular events than classification based on difference in SBP between the first 2 measurements, SBP at 6 months, and average SBP during the first 6 months. Our findings demonstrate heterogeneity in response to antihypertensive therapies and show that chlorthalidone is associated with more favorable initial response than the other medications. © 2017 American Heart Association, Inc.

  16. Annual Progress Report, Fiscal Year 1981.

    DTIC Science & Technology

    1981-09-30

    Ticlopidine Hydrochloride - A Clinical Trial in Patients with Transient Cerebral or Monocular Ischemic Attacks ............... 138 Work Unit No. 81/57...Hand Injuries .................................... 180 Work Unit No. 80/06 (FY8O,C) Evaluation of Antagonistic Knee Flexors and Extensors During Prone...Preventable Training Injury : Accepted for publication in Military Medicine(C). Smith WR, Lee SH, Vichick DA: Evaluation of Antagonistic Knee Flexors and

  17. Recognition of Facial Expressions of Mixed Emotions in School-Age Children Exposed to Terrorism

    ERIC Educational Resources Information Center

    Scrimin, Sara; Moscardino, Ughetta; Capello, Fabia; Altoe, Gianmarco; Axia, Giovanna

    2009-01-01

    This exploratory study aims at investigating the effects of terrorism on children's ability to recognize emotions. A sample of 101 exposed and 102 nonexposed children (mean age = 11 years), balanced for age and gender, were assessed 20 months after a terrorist attack in Beslan, Russia. Two trials controlled for children's ability to match a facial…

  18. Advances in the understanding of cluster headache.

    PubMed

    Leone, Massimo; Proietti Cecchini, Alberto

    2017-02-01

    Cluster headache is the worst primary headache form; it occurs in paroxysmal excruciatingly severe unilateral head pain attacks usually grouped in cluster periods. The familial occurrence of the disease indicates a genetic component but a gene abnormality is yet to be disclosed. Activation of trigeminal afferents and cranial parasympathetic efferents, the so-called trigemino-parasympathetic reflex, can explain pain and accompanying oculo-facial autonomic phenomena. In particular, pain in cluster headache is attributed, at least in part, to the increased CGRP plasma levels released by activated trigeminal system. Posterior hypothalamus was hypothesized to be the cluster generator activating the trigemino-parasympathetic reflex. Efficacy of monoclonal antibodies against CRGP is under investigation in randomized clinical trials. Areas covered: This paper will focus on main findings contributing to consider cluster headache as a neurovascular disorder with an origin from within the brain. Expert commentary: Accumulated evidence with hypothalamic stimulation in cluster headache patients indicate that posterior hypothalamus terminates rather than triggers the attacks. More extensive studies on the genetics of cluster headache are necessary to disclose anomalies behind the increased familial risk of the disease. Results from ongoing clinical trials in cluster headache sufferers using monoclonal antibodies against CGRP will open soon a new era.

  19. Robust multiple frequency multiple power localization schemes in the presence of multiple jamming attacks

    PubMed Central

    2017-01-01

    Localization of the wireless sensor network is a vital area acquiring an impressive research concern and called upon to expand more with the rising of its applications. As localization is gaining prominence in wireless sensor network, it is vulnerable to jamming attacks. Jamming attacks disrupt communication opportunity among the sender and receiver and deeply impact the localization process, leading to a huge error of the estimated sensor node position. Therefore, detection and elimination of jamming influence are absolutely indispensable. Range-based techniques especially Received Signal Strength (RSS) is facing severe impact of these attacks. This paper proposes algorithms based on Combination Multiple Frequency Multiple Power Localization (C-MFMPL) and Step Function Multiple Frequency Multiple Power Localization (SF-MFMPL). The algorithms have been tested in the presence of multiple types of jamming attacks including capture and replay, random and constant jammers over a log normal shadow fading propagation model. In order to overcome the impact of random and constant jammers, the proposed method uses two sets of frequencies shared by the implemented anchor nodes to obtain the averaged RSS readings all over the transmitted frequencies successfully. In addition, three stages of filters have been used to cope with the replayed beacons caused by the capture and replay jammers. In this paper the localization performance of the proposed algorithms for the ideal case which is defined by without the existence of the jamming attack are compared with the case of jamming attacks. The main contribution of this paper is to achieve robust localization performance in the presence of multiple jamming attacks under log normal shadow fading environment with a different simulation conditions and scenarios. PMID:28493977

  20. A Bernoulli Gaussian Watermark for Detecting Integrity Attacks in Control Systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Weerakkody, Sean; Ozel, Omur; Sinopoli, Bruno

    We examine the merit of Bernoulli packet drops in actively detecting integrity attacks on control systems. The aim is to detect an adversary who delivers fake sensor measurements to a system operator in order to conceal their effect on the plant. Physical watermarks, or noisy additive Gaussian inputs, have been previously used to detect several classes of integrity attacks in control systems. In this paper, we consider the analysis and design of Gaussian physical watermarks in the presence of packet drops at the control input. On one hand, this enables analysis in a more general network setting. On the othermore » hand, we observe that in certain cases, Bernoulli packet drops can improve detection performance relative to a purely Gaussian watermark. This motivates the joint design of a Bernoulli-Gaussian watermark which incorporates both an additive Gaussian input and a Bernoulli drop process. We characterize the effect of such a watermark on system performance as well as attack detectability in two separate design scenarios. Here, we consider a correlation detector for attack recognition. We then propose efficiently solvable optimization problems to intelligently select parameters of the Gaussian input and the Bernoulli drop process while addressing security and performance trade-offs. Finally, we provide numerical results which illustrate that a watermark with packet drops can indeed outperform a Gaussian watermark.« less

  1. Security Measures to Protect Mobile Agents

    NASA Astrophysics Data System (ADS)

    Dadhich, Piyanka; Govil, M. C.; Dutta, Kamlesh

    2010-11-01

    The security issues of mobile agent systems have embarrassed its widespread implementation. Mobile agents that move around the network are not safe because the remote hosts that accommodate the agents initiates all kinds of attacks. These hosts try to analyze the agent's decision logic and their accumulated data. So, mobile agent security is the most challenging unsolved problems. The paper analyzes various security measures deeply. Security especially the attacks performed by hosts to the visiting mobile agent (the malicious hosts problem) is a major obstacle that prevents mobile agent technology from being widely adopted. Being the running environment for mobile agent, the host has full control over them and could easily perform many kinds of attacks against them.

  2. Mach 6 experimental and theoretical stability and performance of a cruciform missile at angles of attack up to 65 degrees

    NASA Technical Reports Server (NTRS)

    Hartman, Edward R.; Johnston, Patrick J.

    1987-01-01

    An experimental and theoretical investigation of the longitudinal and lateral-directional stability and control of an axisymmetric cruciform-finned missile has been conducted at Mach 6. The angle-of-attack range extended from 20 to 65 deg to encompass maximum lift. Longitudinal stability, performance, and trim could be accurately predicted with the fins at a fin roll angle of 0 deg but not when the fins were at a fin roll angle of 45 deg. At this roll angle, windward fin choking occurred at angles of attack above 50 deg and reduced the effectiveness of the fins and caused pitch-up.

  3. A randomized clinical trial of cognitive behavioral therapy and interpersonal psychotherapy for panic disorder with agoraphobia.

    PubMed

    Vos, S P F; Huibers, M J H; Diels, L; Arntz, A

    2012-12-01

    Interpersonal psychotherapy (IPT) seems to be as effective as cognitive behavioral therapy (CBT) in the treatment of major depression. Because the onset of panic attacks is often related to increased interpersonal life stress, IPT has the potential to also treat panic disorder. To date, a preliminary open trial yielded promising results but there have been no randomized controlled trials directly comparing CBT and IPT for panic disorder. This study aimed to directly compare the effects of CBT versus IPT for the treatment of panic disorder with agoraphobia. Ninety-one adult patients with a primary diagnosis of DSM-III or DSM-IV panic disorder with agoraphobia were randomized. Primary outcomes were panic attack frequency and an idiosyncratic behavioral test. Secondary outcomes were panic and agoraphobia severity, panic-related cognitions, interpersonal functioning and general psychopathology. Measures were taken at 0, 3 and 4 months (baseline, end of treatment and follow-up). Intention-to-treat (ITT) analyses on the primary outcomes indicated superior effects for CBT in treating panic disorder with agoraphobia. Per-protocol analyses emphasized the differences between treatments and yielded larger effect sizes. Reductions in the secondary outcomes were equal for both treatments, except for agoraphobic complaints and behavior and the credibility ratings of negative interpretations of bodily sensations, all of which decreased more in CBT. CBT is the preferred treatment for panic disorder with agoraphobia compared to IPT. Mechanisms of change should be investigated further, along with long-term outcomes.

  4. Effects of non-invasive vagus nerve stimulation on attack frequency over time and expanded response rates in patients with chronic cluster headache: a post hoc analysis of the randomised, controlled PREVA study.

    PubMed

    Gaul, Charly; Magis, Delphine; Liebler, Eric; Straube, Andreas

    2017-12-01

    In the PREVention and Acute treatment of chronic cluster headache (PREVA) study, attack frequency reductions from baseline were significantly more pronounced with non-invasive vagus nerve stimulation plus standard of care (nVNS + SoC) than with SoC alone. Given the intensely painful and frequent nature of chronic cluster headache attacks, additional patient-centric outcomes, including the time to and level of therapeutic response, were evaluated in a post hoc analysis of the PREVA study. After a 2-week baseline phase, 97 patients with chronic cluster headache entered a 4-week randomised phase to receive nVNS + SoC (n = 48) or SoC alone (n = 49). All 92 patients who continued into a 4-week extension phase received nVNS + SoC. Compared with SoC alone, nVNS + SoC led to a significantly lower mean weekly attack frequency by week 2 of the randomised phase; the attack frequency remained significantly lower in the nVNS + SoC group through week 3 of the extension phase (P < 0.02). Attack frequencies in the nVNS + SoC group were significantly lower at all study time points than they were at baseline (P < 0.05). Response rates were significantly greater with nVNS + SoC than with SoC alone when response was defined as attack frequency reductions of ≥25%, ≥50%, and ≥75% from baseline (≥25% and ≥50%, P < 0.001; ≥75%, P = 0.009). The 100% response rate was 8% with nVNS + SoC and 0% with SoC alone. Prophylactic nVNS led to rapid, significant, and sustained reductions in chronic cluster headache attack frequency within 2 weeks after its addition to SoC and was associated with significantly higher ≥25%, ≥50%, and ≥75% response rates than SoC alone. The rapid decrease in weekly attack frequency justifies a 4-week trial period to identify responders to nVNS, with a high degree of confidence, among patients with chronic cluster headache.

  5. Are fast explorers slow reactors? Linking personality type and anti-predator behaviour

    PubMed Central

    Jones, Katherine A.; Godin, Jean-Guy J.

    2010-01-01

    Response delays to predator attack may be adaptive, suggesting that latency to respond does not always reflect predator detection time, but can be a decision based on starvation–predation risk trade-offs. In birds, some anti-predator behaviours have been shown to be correlated with personality traits such as activity level and exploration. Here, we tested for a correlation between exploration behaviour and response latency time to a simulated fish predator attack in a fish species, juvenile convict cichlids (Amatitlania nigrofasciata). Individual focal fish were subjected to a standardized attack by a robotic fish predator while foraging, and separately given two repeated trials of exploration of a novel environment. We found a strong positive correlation between exploration and time taken to respond to the predator model. Fish that were fast to explore the novel environment were slower to respond to the predator. Our study therefore provides some of the first experimental evidence for a link between exploration behaviour and predator-escape behaviour. We suggest that different behavioural types may differ in how they partition their attention between foraging and anti-predator vigilance. PMID:19864291

  6. Needle-wielding attacker loses bid for retrial for attempted murder.

    PubMed

    1995-06-16

    A Louisiana appeals court upheld a ruling of attempted murder of [name removed] [name removed], an HIV-positive man who attacked a convenience store clerk with a syringe and yelled, "I'll give you AIDS." The clerk, [name removed], tried to telephone police after [name removed] grabbed a carton of cigarettes. [Name removed] pulled a syringe loaded with clear liquid from his pocket and threatened [name removed]. In the altercation, the needle punctured [name removed]'s arm and caused bleeding. Although [name removed] tested negative for HIV antibodies three months after the incident, she testified in the trial that she regarded [name removed]'s statement as a threat upon her life. The court rejected the defense's argument that the state failed to show that the syringe was a dangerous weapon, stating that an attacker does not have to use a dangerous weapon to attempt murder. The Appeals court ruled that it was clear that the prosecution had proved beyond a reasonable doubt that [name removed] was guilty of attempting second-degree murder. He was sentenced to fifty years in prison.

  7. Initial severity and antidepressant efficacy for anxiety disorders, obsessive-compulsive disorder, and posttraumatic stress disorder: An individual patient data meta-analysis.

    PubMed

    de Vries, Ymkje Anna; Roest, Annelieke M; Burgerhof, Johannes G M; de Jonge, Peter

    2018-06-01

    It has been suggested that antidepressant benefits are smaller for mild than severe depression. Because antidepressants are also used for anxiety disorders, obsessive-compulsive disorder (OCD), and posttraumatic stress disorder (PTSD), we examined the influence of severity for these disorders. We used individual patient data of eight trials (3,430 participants) for generalized anxiety disorder (GAD); four trials (1,195 participants) for social anxiety disorder (SAD); four trials (1,132 participants) for OCD; three trials (1,071 participants) for PTSD; and 10 trials (2,151 participants) for panic disorder (PD). Mixed-effects models were used to investigate an interaction between severity and treatment group. For GAD and PD, severity moderated antidepressant efficacy. The antidepressant-placebo difference was 1.4 (95% CI: 0.4-2.5; SMD: 0.21) Hamilton Anxiety Rating Scale (HAM-A) points for participants with mild GAD (baseline HAM-A = 10), increasing to 4.0 (3.4-4.6; SMD: 0.45) or greater for severely ill participants (HAM-A ≥ 30). For PD, the difference was 0.4 (0.3-0.6) panic attacks/2 weeks for participants with 10 panic attacks/2 weeks at baseline, increasing to 4.7 (3.0-6.4) for participants with 40. For SAD, OCD, and PTSD, no interaction was found. Across severity levels, the differences were 16.1 (12.9-19.3; SMD: 0.59) Liebowitz Social Anxiety Scale points, 3.4 (2.5-4.4, SMD: 0.39) Yale-Brown Obsessive-Compulsive Scale points, and 10.3 (6.9-13.6; SMD: 0.41) Clinician-Administered PTSD Scale points. Antidepressants are equally effective across severity levels for SAD, OCD, and PTSD. For GAD and PD, however, benefits are small at low severity, and the benefit-risk ratio may be unfavorable for these patients. © 2018 Wiley Periodicals, Inc.

  8. Effects of electrical stimulation of the lateral aspect of the prefrontal cortex upon attack behavior in cats.

    PubMed

    Siegel, A; Edinger, H; Dotto, M

    1975-08-15

    An experiment was performed to determine the role of the lateral aspect of the prefrontal cortex upon quiet biting attack behavior elicited from the hypothalamus in the cat. The results of this experiment indicate that stimulation of 19 of 28 electrode sites sampled in the lateral prefrontal cortex produced a statistically significant inhibition of attack behavior elicited from the hypothalamus of the ipsilateral side. Stimulation of sites in the prefrontal cortex on the side contralateral to the hypothalamus from which attack was elicited had no effect upon this response. No systematic effect of prefrontal stimulation upon flight behavior was observed. Anatomical studies suggest that the lateral prefrontal cortex may inhibit attack behavior by modulating neurons in either the mediodorsal thalamic nucleus or ventral tegmental area.

  9. Netwar

    NASA Astrophysics Data System (ADS)

    Keen, Arthur A.

    2006-04-01

    This paper describes technology being developed at 21st Century Technologies to automate Computer Network Operations (CNO). CNO refers to DoD activities related to Attacking and Defending Computer Networks (CNA & CND). Next generation cyber threats are emerging in the form of powerful Internet services and tools that automate intelligence gathering, planning, testing, and surveillance. We will focus on "Search-Engine Hacks", queries that can retrieve lists of router/switch/server passwords, control panels, accessible cameras, software keys, VPN connection files, and vulnerable web applications. Examples include "Titan Rain" attacks against DoD facilities and the Santy worm, which identifies vulnerable sites by searching Google for URLs containing application-specific strings. This trend will result in increasingly sophisticated and automated intelligence-driven cyber attacks coordinated across multiple domains that are difficult to defeat or even understand with current technology. One traditional method of CNO relies on surveillance detection as an attack predictor. Unfortunately, surveillance detection is difficult because attackers can perform search engine-driven surveillance such as with Google Hacks, and avoid touching the target site. Therefore, attack observables represent only about 5% of the attacker's total attack time, and are inadequate to provide warning. In order to predict attacks and defend against them, CNO must also employ more sophisticated techniques and work to understand the attacker's Motives, Means and Opportunities (MMO). CNO must use automated reconnaissance tools, such as Google, to identify information vulnerabilities, and then utilize Internet tools to observe the intelligence gathering, planning, testing, and collaboration activities that represent 95% of the attacker's effort.

  10. Migraine attack treatment : a tailor-made suit, not one size fits all.

    PubMed

    Belvis, Robert; Mas, Natalia; Aceituno, Azahara

    2014-04-01

    About 15% of people in the world suffer migraine attacks. Migraine can induce a great impact in the quality of life, and the costs of medical care and loss of productivity can be also high. Non-steroidal anti-inflammatory drugs (NSAIDs) are the best treatment in mild-to-moderate migraine attacks and triptans are the first line option in the acute treatment of moderate-to-severe migraine attacks. At present, there are seven marketed triptans: sumatriptan, rizatriptan, zolmitriptan, eletriptan, naratriptan, almotriptan and frovatriptan. Obviously, every drug presents different pharmacokinetic and pharmacodynamics properties and, moreover, some triptans have several formulations. The prescription of one of these seven triptans for a specified patient is based in the drug profile: efficacy, safety, pharmacokinetics and pharmacodynamics. Other data to take account in the final prescription are clinical characteristics of the migraine attack (speed of onset, intensity of pain, lasting of the attack) and patient characteristics as working habits, life style or medical history. It is therefore mandatory to perform an individualization of the treatment of migraine attack. In recent years, several new patents of drugs have been registered in the treatment of migraine attack, although most of these are already known drugs that only provide new routes of administration. We present an update on the treatment of the migraine attack.

  11. Magnetic resonance imaging/angiography and transcranial Doppler velocities in sickle cell anemia: results from the SWiTCH trial

    PubMed Central

    Helton, Kathleen J.; Adams, Robert J.; Kesler, Karen L.; Lockhart, Alex; Aygun, Banu; Driscoll, Catherine; Heeney, Matthew M.; Jackson, Sherron M.; Krishnamurti, Lakshmanan; Miller, Scott T.; Sarnaik, Sharada A.; Schultz, William H.

    2014-01-01

    The Stroke With Transfusions Changing to Hydroxyurea (SWiTCH) trial compared standard (transfusions/chelation) to alternative (hydroxyurea/phlebotomy) treatment to prevent recurrent stroke and manage iron overload in children chronically transfused over 7 years before enrollment. Standardized brain magnetic resonance imaging/magnetic resonance angiography (MRA) and transcranial Doppler (TCD) exams were performed at entry and exit, with a central blinded review. A novel MRA vasculopathy grading scale demonstrated frequent severe baseline left/right vessel stenosis (53%/41% ≥Grade 4); 31% had no vessel stenosis on either side. Baseline parenchymal injury was prevalent (85%/79% subcortical, 53%/37% cortical, 50%/35% subcortical and cortical). Most children had low or uninterpretable baseline middle cerebral artery TCD velocities, which were associated with worse stenoses (incidence risk ratio [IRR] = 5.1, P ≤ .0001 and IRR = 4.1, P < .0001) than normal velocities; only 2% to 12% had any conditional/abnormal velocity. Patients with adjudicated stroke (7) and transient ischemic attacks (19 in 11 standard/8 alternative arm subjects) had substantial parenchymal injury/vessel stenosis. At exit, 1 child (alternative arm) had a new silent infarct, and another had worse stenosis. SWiTCH neuroimaging data document severe parenchymal and vascular abnormalities in children with SCA and stroke and support concerns about chronic transfusions lacking effectiveness for preventing progressive cerebrovascular injury. The novel SWiTCH vasculopathy grading scale warrants validation testing and consideration for use in future clinical trials. This trial was registered at www.clinicaltrials.gov as #NCT00122980. PMID:24914136

  12. Comparative efficacy of plant-derived essential oils for managing ambrosia beetles (Coleoptera: Curculionidae: Scolytinae) and their corresponding mass spectral characterization.

    PubMed

    Ranger, Christopher M; Reding, Michael E; Oliver, Jason B; Schultz, Peter B; Moyseenko, James J; Youssef, Nadeer

    2011-10-01

    Ambrosia beetles (Coleoptera: Curculionidae: Scolytinae) pose a significant challenge to producers of ornamental nursery stock. Conventional insecticides are commonly used for management purposes, but plant-derived essential oils also may discourage ambrosia beetles from initiating attacks. To identify promising commercially available products, field-based efficacy trials were conducted in Ohio in 2009 and 2010 with the following products: Armorex (Soil Technologies), Cinnacure (Proguard, Inc.), EcoTrol (EcoSMART Technologies, Inc.), and Veggie Pharm (Pharm Solutions, Inc.). Potted Magnolia virginiana L. were first injected with 75 ml of 5% ethanol to ensure ambrosia beetle pressure on experimental trees. Mixtures of each product (10% in water) and a water control were applied until runoff and attacks occurring under field conditions were quantified at 1, 4, 7, and 14 d after treatment (DAT). Ambrosia beetle attacks generally increased over time but at differing rates depending on the particular treatment. In 2009, Armorex and Veggie Pharm were associated with the lowest cumulative attacks 14 DAT. In 2010, Armorex and Cinnacure were associated with the fewest attacks 14 DAT. Solid phase microextraction-gas chromatography-mass spectrometry was used to characterize the volatile compounds associated with each product. Allyl isothiocyanate, a compound with known repellent and insecticidal properties, was unique and predominant in Armorex. These experiments identified commercially available botanicals containing plant essential oils with activity against ambrosia beetles, along with demonstrating the usefulness of ethanol-injection to ensure ambrosia beetle pressure under field conditions. Characterizing the constituents of efficacious botanically based products could also lead to the development of improved botanical insecticides.

  13. A Comparative Study of Unsupervised Anomaly Detection Techniques Using Honeypot Data

    NASA Astrophysics Data System (ADS)

    Song, Jungsuk; Takakura, Hiroki; Okabe, Yasuo; Inoue, Daisuke; Eto, Masashi; Nakao, Koji

    Intrusion Detection Systems (IDS) have been received considerable attention among the network security researchers as one of the most promising countermeasures to defend our crucial computer systems or networks against attackers on the Internet. Over the past few years, many machine learning techniques have been applied to IDSs so as to improve their performance and to construct them with low cost and effort. Especially, unsupervised anomaly detection techniques have a significant advantage in their capability to identify unforeseen attacks, i.e., 0-day attacks, and to build intrusion detection models without any labeled (i.e., pre-classified) training data in an automated manner. In this paper, we conduct a set of experiments to evaluate and analyze performance of the major unsupervised anomaly detection techniques using real traffic data which are obtained at our honeypots deployed inside and outside of the campus network of Kyoto University, and using various evaluation criteria, i.e., performance evaluation by similarity measurements and the size of training data, overall performance, detection ability for unknown attacks, and time complexity. Our experimental results give some practical and useful guidelines to IDS researchers and operators, so that they can acquire insight to apply these techniques to the area of intrusion detection, and devise more effective intrusion detection models.

  14. Physical and thermal strain of firefighters according to the firefighting tactics used to suppress wildfires.

    PubMed

    Rodríguez-Marroyo, J A; Villa, J G; López-Satue, J; Pernía, R; Carballo, B; García-López, J; Foster, C

    2011-11-01

    The aim of this study was to analyse the physiological strain of firefighters, using heart rate (HR) and core temperature, during real wildfire suppression according to the type of attack performed (direct, indirect or mixed). Three intensity zones were established according to the HR corresponding to the ventilatory threshold (VT) and respiratory compensation threshold (RCT): zone 1, RCT. The exercise workload (training impulse (TRIMP)), the physiological strain index (PSI) and the cumulative heat strain index(CHSI) were calculated using the time spent in each zone, and the HR and core temperature, respectively. Significantly higher mean HR, time spent in Z2 and Z3 and TRIMP h(-1) were found in direct and mixed versus indirect attacks. The highest PSI and CHSI were observed in the direct attack. In conclusion, exercise strain and combined thermal strain, but not core temperature during wildfire suppression, are related to the type of attack performed. STATEMENT OF RELEVANCE: Our findings demonstrated that wildfire firefighting is associated with high physiological demands, which vary significantly depending on the tactics chosen for performing the task. These results should be kept in mind when planning programmes to improve wildland firefighters' physical fitness, which will allow improvement in their performance.

  15. Exploratory low-speed wind-tunnel study of concepts designed to improve aircraft stability and control at high angles of attack. M.S. Thesis

    NASA Technical Reports Server (NTRS)

    Hahne, D. E.

    1985-01-01

    A wind tunnel investigation of concepts to improve the high angle-of-attack stability and control characteristics of a high performance aircraft was conducted. The effect of vertical tail geometry on stability and the effectiveness of several conventional and unusual control concepts was determined. These results were obtained over a large angle-of-attack range. Vertical tail location, cant angle and leading edge sweep could influence both longitudinal and lateral-directional stability. The control concepts tested were found to be effective and to provide control into the post stall angle-of-attack region.

  16. How players exploit variability and regularity of game actions in female volleyball teams.

    PubMed

    Ramos, Ana; Coutinho, Patrícia; Silva, Pedro; Davids, Keith; Mesquita, Isabel

    2017-05-01

    Variability analysis has been used to understand how competitive constraints shape different behaviours in team sports. In this study, we analysed and compared variability of tactical performance indices in players within complex I at two different competitive levels in volleyball. We also examined whether variability was influenced by set type and period. Eight matches from the 2012 Olympics competition and from the Portuguese national league in the 2014-2015 season were analysed (1496 rallies). Variability of setting conditions, attack zone, attack tempo and block opposition was assessed using Shannon entropy measures. Magnitude-based inferences were used to analyse the practical significance of compared values of selected variables. Results showed differences between elite and national teams for all variables, which were co-adapted to the competitive constraints of set type and set periods. Elite teams exploited system stability in setting conditions and block opposition, but greater unpredictability in zone and tempo of attack. These findings suggest that uncertainty in attacking actions was a key factor that could only be achieved with greater performance stability in other game actions. Data suggested how coaches could help setters develop the capacity to play at faster tempos, diversifying attack zones, especially at critical moments in competition.

  17. Risk for Major Bleeding in Patients Receiving Ticagrelor Compared With Aspirin After Transient Ischemic Attack or Acute Ischemic Stroke in the SOCRATES Study (Acute Stroke or Transient Ischemic Attack Treated With Aspirin or Ticagrelor and Patient Outcomes).

    PubMed

    Easton, J Donald; Aunes, Maria; Albers, Gregory W; Amarenco, Pierre; Bokelund-Singh, Sara; Denison, Hans; Evans, Scott R; Held, Peter; Jahreskog, Marianne; Jonasson, Jenny; Minematsu, Kazuo; Molina, Carlos A; Wang, Yongjun; Wong, K S Lawrence; Johnston, S Claiborne

    2017-09-05

    Patients with minor acute ischemic stroke or transient ischemic attack are at high risk for subsequent stroke, and more potent antiplatelet therapy in the acute setting is needed. However, the potential benefit of more intense antiplatelet therapy must be assessed in relation to the risk for major bleeding. The SOCRATES trial (Acute Stroke or Transient Ischemic Attack Treated With Aspirin or Ticagrelor and Patient Outcomes) was the first trial with ticagrelor in patients with acute ischemic stroke or transient ischemic attack in which the efficacy and safety of ticagrelor were compared with those of aspirin. The main safety objective was assessment of PLATO (Platelet Inhibition and Patient Outcomes)-defined major bleeds on treatment, with special focus on intracranial hemorrhage (ICrH). An independent adjudication committee blinded to study treatment classified bleeds according to the PLATO, TIMI (Thrombolysis in Myocardial Infarction), and GUSTO (Global Use of Strategies to Open Occluded Coronary Arteries) definitions. The definitions of ICrH and major bleeding excluded cerebral microbleeds and asymptomatic hemorrhagic transformations of cerebral infarctions so that the definitions better discriminated important events in the acute stroke population. A total of 13 130 of 13 199 randomized patients received at least 1 dose of study drug and were included in the safety analysis set. PLATO major bleeds occurred in 31 patients (0.5%) on ticagrelor and 38 patients (0.6%) on aspirin (hazard ratio, 0.83; 95% confidence interval, 0.52-1.34). The most common locations of major bleeds were intracranial and gastrointestinal. ICrH was reported in 12 patients (0.2%) on ticagrelor and 18 patients (0.3%) on aspirin. Thirteen of all 30 ICrHs (4 on ticagrelor and 9 on aspirin) were hemorrhagic strokes, and 4 (2 in each group) were symptomatic hemorrhagic transformations of brain infarctions. The ICrHs were spontaneous in 6 and 13, traumatic in 3 and 3, and procedural in 3 and 2 patients on ticagrelor and aspirin, respectively. In total, 9 fatal bleeds occurred on ticagrelor and 4 on aspirin. The composite of ICrH or fatal bleeding included 15 patients on ticagrelor and 18 on aspirin. Independently of bleeding classification, PLATO, TIMI, or GUSTO, the relative difference between treatments for major/severe bleeds was similar. Nonmajor bleeds were more common on ticagrelor. Antiplatelet therapy with ticagrelor in patients with acute ischemic stroke or transient ischemic attack showed a bleeding profile similar to that of aspirin for major bleeds. There were few ICrHs. URL: http://www.clinicaltrials.gov. Unique identifier: NCT01994720. © 2017 American Heart Association, Inc.

  18. Robust Structural Analysis and Design of Distributed Control Systems to Prevent Zero Dynamics Attacks

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Weerakkody, Sean; Liu, Xiaofei; Sinopoli, Bruno

    We consider the design and analysis of robust distributed control systems (DCSs) to ensure the detection of integrity attacks. DCSs are often managed by independent agents and are implemented using a diverse set of sensors and controllers. However, the heterogeneous nature of DCSs along with their scale leave such systems vulnerable to adversarial behavior. To mitigate this reality, we provide tools that allow operators to prevent zero dynamics attacks when as many as p agents and sensors are corrupted. Such a design ensures attack detectability in deterministic systems while removing the threat of a class of stealthy attacks in stochasticmore » systems. To achieve this goal, we use graph theory to obtain necessary and sufficient conditions for the presence of zero dynamics attacks in terms of the structural interactions between agents and sensors. We then formulate and solve optimization problems which minimize communication networks while also ensuring a resource limited adversary cannot perform a zero dynamics attacks. Polynomial time algorithms for design and analysis are provided.« less

  19. Thirty-Day Outcome of a Multicenter Registry Study of Stenting for Symptomatic Intracranial Artery Stenosis in China.

    PubMed

    Miao, Zhongrong; Zhang, Yong; Shuai, Jie; Jiang, Changchun; Zhu, Qiyi; Chen, Kangning; Liu, Li; Li, Baomin; Shi, Xiangqun; Gao, Lianbo; Liu, Yajie; Wang, Feng; Li, Yongli; Liu, Tieyan; Zheng, Hongbo; Wang, Yilong; Wang, Yongjun

    2015-10-01

    Although recent trials have suggested that stenting is worse than medical therapy for patients with severe symptomatic intracranial atherosclerotic stenosis, it is not clear whether this conclusion applies to a subset of patients with hypoperfusion symptoms. To justify for a new trial in China, we performed a multicenter prospective registry study to evaluate the safety and efficacy of endovascular stenting within 30 days for patients with severe symptomatic intracranial atherosclerotic stenosis. Patients with symptomatic intracranial atherosclerotic stenosis caused by 70% to 99% stenosis combined with poor collaterals were enrolled. The patients were treated either with balloon-mounted stent or with balloon predilation plus self-expanding stent as determined by the operators following a guideline. The primary outcome within 30 days is stroke, transient ischemic attack, and death after stenting. The secondary outcome is successful revascularization. The baseline characteristics and outcomes of the 2 treatment groups were compared. From September 2013 to January 2015, among 354 consecutive patients, 300 patients (aged 58.3±9.78 years) were recruited, including 159 patients treated with balloon-mounted stent and 141 patients with balloon plus self-expanding stent. The 30-day rate of stroke, transient ischemic attack, and death was 4.3%. Successful revascularization was 97.3%. Patients treated with balloon-mounted stent were older, less likely to have middle cerebral artery lesions, more likely to have vertebral artery lesions, more likely to have Mori A lesions, less likely to have Mori C lesions, and likely to have lower degree of residual stenosis than patients treated with balloon plus self-expanding stent. The short-term safety and efficacy of endovascular stenting for patients with severe symptomatic intracranial atherosclerotic stenosis in China is acceptable. Balloon-mounted stent may have lower degree of residual stenosis than self-expanding stent. URL: http://www.clinicaltrials.gov. Unique identifier: NCT01968122. © 2015 American Heart Association, Inc.

  20. dLocAuth: a dynamic multifactor authentication scheme for mCommerce applications using independent location-based obfuscation

    NASA Astrophysics Data System (ADS)

    Kuseler, Torben; Lami, Ihsan A.

    2012-06-01

    This paper proposes a new technique to obfuscate an authentication-challenge program (named LocProg) using randomly generated data together with a client's current location in real-time. LocProg can be used to enable any handsetapplication on mobile-devices (e.g. mCommerce on Smartphones) that requires authentication with a remote authenticator (e.g. bank). The motivation of this novel technique is to a) enhance the security against replay attacks, which is currently based on using real-time nonce(s), and b) add a new security factor, which is location verified by two independent sources, to challenge / response methods for authentication. To assure a secure-live transaction, thus reducing the possibility of replay and other remote attacks, the authors have devised a novel technique to obtain the client's location from two independent sources of GPS on the client's side and the cellular network on authenticator's side. The algorithm of LocProg is based on obfuscating "random elements plus a client's data" with a location-based key, generated on the bank side. LocProg is then sent to the client and is designed so it will automatically integrate into the target application on the client's handset. The client can then de-obfuscate LocProg if s/he is within a certain range around the location calculated by the bank and if the correct personal data is supplied. LocProg also has features to protect against trial/error attacks. Analysis of LocAuth's security (trust, threat and system models) and trials based on a prototype implementation (on Android platform) prove the viability and novelty of LocAuth.

  1. New clinical trial uses targeted cancer drug for lymphatic system disease | Center for Cancer Research

    Cancer.gov

    Nivolumab is a targeted cancer drug that blocks the action of a protein called PD-1 and activates T cells to attack cancer cells without damaging normal cells. Mark Roschewski, M.D., of the Lymphoid Malignancies Branch is leading a study to determine if nivolumab is effective in treating patients with certain diseases of the lymphatic system.

  2. Thermal performance of two indigenous pupal parasitoids attacking the invasive Drosophila suzukii (Diptera: Drosophilidae)

    USDA-ARS?s Scientific Manuscript database

    Pachycrepoideus vindemiae (Rondani) and Trichopria drosophilae (Perkins) are among a few indigenous parasitoids attacking the invasive Drosophila suzukii (Matsumura) (Diptera: Drosophilidae) in North America. Both parasitoid species occur in California, whereas only P. vindemiae has been reported fr...

  3. Augmentation of maneuver performance by spanwise blowing

    NASA Technical Reports Server (NTRS)

    Erickson, G. E.; Campbell, J. F.

    1977-01-01

    A generalized wind tunnel model was tested to investigate new component concepts utilizing spanwise blowing to provide improved maneuver characteristics for advanced fighter aircraft. Primary emphasis was placed on high angle of attack performance, stability, and control at subsonic speeds. Spanwise blowing on a 44 deg swept trapezoidal wing resulted in leading edge vortex enhancement with subsequent large vortex-induced lift increments and drag polar improvements at the higher angles of attack. Small deflections of a leading edge flap delayed these lift and drag benefits to higher angles of attack. In addition, blowing was more effective at higher Mach numbers. Spanwise blowing in conjunction with a deflected trailing edge flap resulted in lift and drag benefits that exceeded the summation of the effects of each high lift device acting alone. Asymmetric blowing was an effective lateral control device at the higher angles of attack. Spanwise blowing on the wing reduced horizontal tail loading and improved the lateral-directional stability characteristics of a wing-horizontal tail-vertical tail configuration.

  4. Interpersonal distance regulates functional grouping tendencies of agents in team sports.

    PubMed

    Passos, Pedro; Milho, João; Fonseca, Sofia; Borges, João; Araújo, Duarte; Davids, Keith

    2011-01-01

    The authors examined whether, similar to collective agent behaviors in complex, biological systems (e.g., schools of fish and colonies of ants), performers in team sports displayed functional coordination tendencies, based on local interaction rules during performance. To investigate this issue, they used videogrammetry and digitizing procedures to observe interpersonal interactions in common 4 versus 2 + 2 subphases of the team sport of rugby union, involving 16 participants aged between 16 and 17 years of age. They observed pattern-forming dynamics in attacking subunits (n = 4 players) attempting to penetrate 2 defensive lines (n = 2 players in each). Data showed that within each attacking subunit, the 4 players displayed emergent functional grouping tendencies that differed between the 2 defensive lines. Results confirmed that grouping tendencies in attacking subunits of team games are sensitive to different task constraints, such as relative positioning to nearest defenders. It was concluded that running correlations were particularly useful for measuring the level of interpersonal coordination in functional grouping tendencies within attacking subunits.

  5. Effectiveness of an electronic patient-centred self-management tool for gout sufferers: a cluster randomised controlled trial protocol

    PubMed Central

    Frensham, Lauren J; Nguyen, Amy D; Baysari, Melissa T; Aung, Eindra; Lau, Annie Y S; Zwar, Nicholas; Reath, Jennifer; Li, Ling; McLachlan, Andrew; Runciman, William B; Buchbinder, Rachelle; Clay-Williams, Robyn; Braithwaite, Jeffrey; McNeil, H Patrick; Pile, Kevin D; Portek, Ian; WIlliams, Kenneth Mapson; Westbrook, Johanna I

    2017-01-01

    Introduction Gout is increasing despite effective therapies to lower serum urate concentrations to 0.36 mmol/L or less, which, if sustained, significantly reduces acute attacks of gout. Adherence to urate-lowering therapy (ULT) is poor, with rates of less than 50% 1 year after initiation of ULT. Attempts to increase adherence in gout patients have been disappointing. We aim to evaluate the effectiveness of use of a personal, self-management, ‘smartphone’ application (app) to achieve target serum urate concentrations in people with gout. We hypothesise that personalised feedback of serum urate concentrations will improve adherence to ULT. Methods and analysis Setting and design Primary care. A prospective, cluster randomised (by general practitioner (GP) practices), controlled trial. Participants GP practices will be randomised to either intervention or control clusters with their patients allocated to the same cluster. Intervention The intervention group will have access to the Healthy.me app tailored for the self-management of gout. The control group patients will have access to the same app modified to remove all functions except the Gout Attack Diary. Primary and secondary outcomes The proportion of patients whose serum urate concentrations are less than or equal to 0.36 mmol/L after 6 months. Secondary outcomes will be proportions of patients achieving target urate concentrations at 12 months, ULT adherence rates, serum urate concentrations at 6 and 12 months, rates of attacks of gout, quality of life estimations and process and economic evaluations. The study is designed to detect a ≥30% improvement in the intervention group above the expected 50% achievement of target serum urate at 6 months in the control group: power 0.80, significance level 0.05, assumed ‘dropout’ rate 20%. Ethics and dissemination This study has been approved by the University of New South Wales Human Research Ethics Committee. Study findings will be disseminated in international conferences and peer-reviewed journal. Trial registration number ACTRN12616000455460. PMID:29042386

  6. General immunity and superadditivity of two-way Gaussian quantum cryptography.

    PubMed

    Ottaviani, Carlo; Pirandola, Stefano

    2016-03-01

    We consider two-way continuous-variable quantum key distribution, studying its security against general eavesdropping strategies. Assuming the asymptotic limit of many signals exchanged, we prove that two-way Gaussian protocols are immune to coherent attacks. More precisely we show the general superadditivity of the two-way security thresholds, which are proven to be higher than the corresponding one-way counterparts in all cases. We perform the security analysis first reducing the general eavesdropping to a two-mode coherent Gaussian attack, and then showing that the superadditivity is achieved by exploiting the random on/off switching of the two-way quantum communication. This allows the parties to choose the appropriate communication instances to prepare the key, accordingly to the tomography of the quantum channel. The random opening and closing of the circuit represents, in fact, an additional degree of freedom allowing the parties to convert, a posteriori, the two-mode correlations of the eavesdropping into noise. The eavesdropper is assumed to have no access to the on/off switching and, indeed, cannot adapt her attack. We explicitly prove that this mechanism enhances the security performance, no matter if the eavesdropper performs collective or coherent attacks.

  7. Anti-collusion forensics of multimedia fingerprinting using orthogonal modulation.

    PubMed

    Wang, Z Jane; Wu, Min; Zhao, Hong Vicky; Trappe, Wade; Liu, K J Ray

    2005-06-01

    Digital fingerprinting is a method for protecting digital data in which fingerprints that are embedded in multimedia are capable of identifying unauthorized use of digital content. A powerful attack that can be employed to reduce this tracing capability is collusion, where several users combine their copies of the same content to attenuate/remove the original fingerprints. In this paper, we study the collusion resistance of a fingerprinting system employing Gaussian distributed fingerprints and orthogonal modulation. We introduce the maximum detector and the thresholding detector for colluder identification. We then analyze the collusion resistance of a system to the averaging collusion attack for the performance criteria represented by the probability of a false negative and the probability of a false positive. Lower and upper bounds for the maximum number of colluders K(max) are derived. We then show that the detectors are robust to different collusion attacks. We further study different sets of performance criteria, and our results indicate that attacks based on a few dozen independent copies can confound such a fingerprinting system. We also propose a likelihood-based approach to estimate the number of colluders. Finally, we demonstrate the performance for detecting colluders through experiments using real images.

  8. General immunity and superadditivity of two-way Gaussian quantum cryptography

    PubMed Central

    Ottaviani, Carlo; Pirandola, Stefano

    2016-01-01

    We consider two-way continuous-variable quantum key distribution, studying its security against general eavesdropping strategies. Assuming the asymptotic limit of many signals exchanged, we prove that two-way Gaussian protocols are immune to coherent attacks. More precisely we show the general superadditivity of the two-way security thresholds, which are proven to be higher than the corresponding one-way counterparts in all cases. We perform the security analysis first reducing the general eavesdropping to a two-mode coherent Gaussian attack, and then showing that the superadditivity is achieved by exploiting the random on/off switching of the two-way quantum communication. This allows the parties to choose the appropriate communication instances to prepare the key, accordingly to the tomography of the quantum channel. The random opening and closing of the circuit represents, in fact, an additional degree of freedom allowing the parties to convert, a posteriori, the two-mode correlations of the eavesdropping into noise. The eavesdropper is assumed to have no access to the on/off switching and, indeed, cannot adapt her attack. We explicitly prove that this mechanism enhances the security performance, no matter if the eavesdropper performs collective or coherent attacks. PMID:26928053

  9. Notes on a Continuous-Variable Quantum Key Distribution Scheme

    NASA Astrophysics Data System (ADS)

    Ichikawa, Tsubasa; Hirano, Takuya; Matsubara, Takuto; Ono, Motoharu; Namiki, Ryo

    2017-09-01

    We develop a physical model to describe the signal transmission for a continuous-variable quantum key distribution scheme and investigate its security against a couple of eavesdropping attacks assuming that the eavesdropper's power is partly restricted owing to today's technological limitations. We consider an eavesdropper performing quantum optical homodyne measurement on the signal obtained by a type of beamsplitting attack. We also consider the case in which the eavesdropper Eve is unable to access a quantum memory and she performs heterodyne measurement on her signal without performing a delayed measurement. Our formulation includes a model in which the receiver's loss and noise are unaccessible by the eavesdropper. This setup enables us to investigate the condition that Eve uses a practical fiber differently from the usual beamsplitting attack where she can deploy a lossless transmission channel. The secret key rates are calculated in both the direct and reverse reconciliation scenarios.

  10. H.264/AVC digital fingerprinting based on spatio-temporal just noticeable distortion

    NASA Astrophysics Data System (ADS)

    Ait Saadi, Karima; Bouridane, Ahmed; Guessoum, Abderrezak

    2014-01-01

    This paper presents a robust adaptive embedding scheme using a modified Spatio-Temporal noticeable distortion (JND) model that is designed for tracing the distribution of the H.264/AVC video content and protecting them from unauthorized redistribution. The Embedding process is performed during coding process in selected macroblocks type Intra 4x4 within I-Frame. The method uses spread-spectrum technique in order to obtain robustness against collusion attacks and the JND model to dynamically adjust the embedding strength and control the energy of the embedded fingerprints so as to ensure their imperceptibility. Linear and non linear collusion attacks are performed to show the robustness of the proposed technique against collusion attacks while maintaining visual quality unchanged.

  11. Neuropsychological and SPECT scan findings during and after transient global amnesia: evidence for the differential impairment of remote episodic memory.

    PubMed

    Evans, J; Wilson, B; Wraight, E P; Hodges, J R

    1993-11-01

    A patient had neuropsychological testing during, and at two days and seven weeks after a transient global amnesia (TGA) attack. During the attack she exhibited a characteristically profound anterograde amnesia but a limited remote memory loss; the most striking impairment was a deficit in personal episodic memory revealed by her performance on the Autobiographical Memory Interview. Personal and general semantic information was less impaired although there were indications of a temporal gradient in the impairment. When tested after the attack, she demonstrated normal anterograde and retrograde memory. A SPECT scan performed during TGA showed a focal reduction in cerebral perfusion in the postero-medial temporal lobes bilaterally which had resolved after seven weeks.

  12. Switching LPV Control for High Performance Tactical Aircraft

    NASA Technical Reports Server (NTRS)

    Lu, Bei; Wu, Fen; Kim, SungWan

    2004-01-01

    This paper examines a switching Linear Parameter-Varying (LPV) control approach to determine if it is practical to use for flight control designs within a wide angle of attack region. The approach is based on multiple parameter-dependent Lyapunov functions. The full parameter space is partitioned into overlapping subspaces and a family of LPV controllers are designed, each suitable for a specific parameter subspace. The hysteresis switching logic is used to accomplish the transition among different parameter subspaces. The proposed switching LPV control scheme is applied to an F-16 aircraft model with different actuator dynamics in low and high angle of attack regions. The nonlinear simulation results show that the aircraft performs well when switching among different angle of attack regions.

  13. CobraPLA Insertion by anesthetists and non-anesthetists wearing unconventional protective gear: a prospective study in humans.

    PubMed

    Ben-Abraham, Ron; Flaishon, Ron; Sotman, Alexander; Ekstein, Perla; Ezri, Tiberiu; Ogorek, Daniel; Weinbroum, Avi A

    2008-07-01

    The threat of a mass casualty unconventional attack has challenged the medical community to devise means for providing rapid and reliable emergent airway control under chaotic conditions by inexperienced medical personnel dressed in self protective gear. Since endotracheal intubation may not be feasible under those conditions, other extraglottic devices should be considered. We assessed the performance of anesthesia and non-anesthesia residents in inserting the CobraPLA, a supraglottic airway device, on consecutive anesthetized patients, to assess its potential use under simulated conditions. Anesthesia and non-anesthesia residents wearing either surgical scrubs or complete anti-chemical gear inserted the CobraPLA in anesthetized patients. If post-trial positive pressure ventilation via the CobraPLA was unsuccessful, an LMA or endotracheal tube was inserted in its stead. It took anesthesia residents 57+/-23 sec and 43+/-13 sec (P<0.05) to place the CobraPLA while wearing anti-chemical gear and surgical scrubs, respectively. Non-anesthesia residents wearing anti-chemical gear performed worse than anesthetists in their first insertion (73+/-9 sec, P<0.05), but after the brief training period they performed as well as their colleagues anesthetists (58+/-10 sec, P=NS). Post-trial, twenty-one CobraPLA (42%) leaked, preventing adequate positive-pressure ventilation: 13 devices (26% of the total) required replacements. Anti-chemical protective gear slowed the insertion of the CobraPLA by anesthetists, and more so by other residents inexperienced in airway management. In 26% of the cases CobraPLA was inadequate for positive pressure ventilation.

  14. Improving the multiparty quantum secret sharing over two collective-noise channels against insider attack

    NASA Astrophysics Data System (ADS)

    Sun, Ying; Wen, Qiao-yan; Zhu, Fu-chen

    2010-01-01

    The security of the multiparty quantum secret sharing protocol presented by Zhang [Z.J. Zhang, Physica A, 361 (2006) 233] is analyzed. It is shown that this protocol is vulnerable to the insider attack since eavesdropping detection is performed only when all states arrive at the last agent. We propose an attack strategy and give an improved version of the original protocol. The improved protocol is robust and has the same traits with the original one.

  15. DCT-based cyber defense techniques

    NASA Astrophysics Data System (ADS)

    Amsalem, Yaron; Puzanov, Anton; Bedinerman, Anton; Kutcher, Maxim; Hadar, Ofer

    2015-09-01

    With the increasing popularity of video streaming services and multimedia sharing via social networks, there is a need to protect the multimedia from malicious use. An attacker may use steganography and watermarking techniques to embed malicious content, in order to attack the end user. Most of the attack algorithms are robust to basic image processing techniques such as filtering, compression, noise addition, etc. Hence, in this article two novel, real-time, defense techniques are proposed: Smart threshold and anomaly correction. Both techniques operate at the DCT domain, and are applicable for JPEG images and H.264 I-Frames. The defense performance was evaluated against a highly robust attack, and the perceptual quality degradation was measured by the well-known PSNR and SSIM quality assessment metrics. A set of defense techniques is suggested for improving the defense efficiency. For the most aggressive attack configuration, the combination of all the defense techniques results in 80% protection against cyber-attacks with PSNR of 25.74 db.

  16. Performance Evaluation of AODV with Blackhole Attack

    NASA Astrophysics Data System (ADS)

    Dara, Karuna

    2010-11-01

    A Mobile Ad Hoc Network (MANET) is a temporary network set up by a wireless mobile computers moving arbitrary in the places that have no network infrastructure. These nodes maintain connectivity in a decentralized manner. Since the nodes communicate with each other, they cooperate by forwarding data packets to other nodes in the network. Thus the nodes find a path to the destination node using routing protocols. However, due to security vulnerabilities of the routing protocols, mobile ad-hoc networks are unprotected to attacks of the malicious nodes. One of these attacks is the Black Hole Attack against network integrity absorbing all data packets in the network. Since the data packets do not reach the destination node on account of this attack, data loss will occur. In this paper, we simulated the black hole attack in various mobile ad-hoc network scenarios using AODV routing protocol of MANET and have tried to find a effect if number of nodes are increased with increase in malicious nodes.

  17. Temporal Cyber Attack Detection.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ingram, Joey Burton; Draelos, Timothy J.; Galiardi, Meghan

    Rigorous characterization of the performance and generalization ability of cyber defense systems is extremely difficult, making it hard to gauge uncertainty, and thus, confidence. This difficulty largely stems from a lack of labeled attack data that fully explores the potential adversarial space. Currently, performance of cyber defense systems is typically evaluated in a qualitative manner by manually inspecting the results of the system on live data and adjusting as needed. Additionally, machine learning has shown promise in deriving models that automatically learn indicators of compromise that are more robust than analyst-derived detectors. However, to generate these models, most algorithms requiremore » large amounts of labeled data (i.e., examples of attacks). Algorithms that do not require annotated data to derive models are similarly at a disadvantage, because labeled data is still necessary when evaluating performance. In this work, we explore the use of temporal generative models to learn cyber attack graph representations and automatically generate data for experimentation and evaluation. Training and evaluating cyber systems and machine learning models requires significant, annotated data, which is typically collected and labeled by hand for one-off experiments. Automatically generating such data helps derive/evaluate detection models and ensures reproducibility of results. Experimentally, we demonstrate the efficacy of generative sequence analysis techniques on learning the structure of attack graphs, based on a realistic example. These derived models can then be used to generate more data. Additionally, we provide a roadmap for future research efforts in this area.« less

  18. Intrusion-Tolerant Replication under Attack

    ERIC Educational Resources Information Center

    Kirsch, Jonathan

    2010-01-01

    Much of our critical infrastructure is controlled by large software systems whose participants are distributed across the Internet. As our dependence on these critical systems continues to grow, it becomes increasingly important that they meet strict availability and performance requirements, even in the face of malicious attacks, including those…

  19. On effectiveness of network sensor-based defense framework

    NASA Astrophysics Data System (ADS)

    Zhang, Difan; Zhang, Hanlin; Ge, Linqiang; Yu, Wei; Lu, Chao; Chen, Genshe; Pham, Khanh

    2012-06-01

    Cyber attacks are increasing in frequency, impact, and complexity, which demonstrate extensive network vulnerabilities with the potential for serious damage. Defending against cyber attacks calls for the distributed collaborative monitoring, detection, and mitigation. To this end, we develop a network sensor-based defense framework, with the aim of handling network security awareness, mitigation, and prediction. We implement the prototypical system and show its effectiveness on detecting known attacks, such as port-scanning and distributed denial-of-service (DDoS). Based on this framework, we also implement the statistical-based detection and sequential testing-based detection techniques and compare their respective detection performance. The future implementation of defensive algorithms can be provisioned in our proposed framework for combating cyber attacks.

  20. Practical security and privacy attacks against biometric hashing using sparse recovery

    NASA Astrophysics Data System (ADS)

    Topcu, Berkay; Karabat, Cagatay; Azadmanesh, Matin; Erdogan, Hakan

    2016-12-01

    Biometric hashing is a cancelable biometric verification method that has received research interest recently. This method can be considered as a two-factor authentication method which combines a personal password (or secret key) with a biometric to obtain a secure binary template which is used for authentication. We present novel practical security and privacy attacks against biometric hashing when the attacker is assumed to know the user's password in order to quantify the additional protection due to biometrics when the password is compromised. We present four methods that can reconstruct a biometric feature and/or the image from a hash and one method which can find the closest biometric data (i.e., face image) from a database. Two of the reconstruction methods are based on 1-bit compressed sensing signal reconstruction for which the data acquisition scenario is very similar to biometric hashing. Previous literature introduced simple attack methods, but we show that we can achieve higher level of security threats using compressed sensing recovery techniques. In addition, we present privacy attacks which reconstruct a biometric image which resembles the original image. We quantify the performance of the attacks using detection error tradeoff curves and equal error rates under advanced attack scenarios. We show that conventional biometric hashing methods suffer from high security and privacy leaks under practical attacks, and we believe more advanced hash generation methods are necessary to avoid these attacks.

  1. Video analysis of acute injuries and referee decisions during the 24th Men's Handball World Championship 2015 in Qatar.

    PubMed

    Andersson, S H; Cardinale, M; Whiteley, R; Popovic, N; Hansen, C; Lopez, F S; Bere, T; Bahr, R; Myklebust, G

    2018-03-30

    Although handball is a contact sport with a high risk of acute match injuries, their mechanisms have not yet been investigated. We aimed to describe the mechanisms of acute match injuries in elite male handball and evaluate referee performance in injury situations. Based on injury surveillance from the 24th Men's Handball World Championship 2015 in Qatar, injury situations and the referee decisions were identified on video footage. A total of 55 injury situations and 37 referee decisions were included for analysis. The injury situations were analyzed individually by five handball experts, followed by a consensus meeting. An expert referee panel performed individual blinded evaluation of the referee decisions, followed by an online consensus meeting. Injuries were evenly distributed among attackers (n = 29) and defenders (n = 26). The most frequent injury cause was contact trauma due to a tackle (n = 27). At the time of injury, attackers were most frequently performing a jump shot (n = 9), while defenders were completing a tackle (n = 10). Defenders most commonly tackled the throwing arm (n = 7) or toward the head/face region (n = 6) of injured attackers, while attackers most frequently hit injured defenders with the knee during jump shots (n = 5). Agreement between the referees and the expert panel was weak (kappa: 0.22, 95% CI 0.07 to 0.36), with substantially more lenient rule interpretation by the referees. Our results suggest that stricter refereeing and rule amendments should be considered to prevent acute match injuries in elite handball, especially in relation to tackling episodes when an attacker is performing a jump shot. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  2. Wind turbine blades: A study of prototypes in a steady regime - Unsteady considerations

    NASA Astrophysics Data System (ADS)

    Leblanc, R.; Goethals, R.; de Saint Louvent, B.

    1981-11-01

    The results of comparisons of numerical models with experimental results for the performance of prototype wind turbines in steady flows are presented, along with preliminary results on behavior in unsteady flows. The numerical models are based on previous schemes devised for propellers, with modifications for small perturbations, significant radial velocity effects from the wake, and the fact that the speed is induced. Two computational methods are currently used, one a method of short blades, the other the Prandtl lifting line theory. Trials have been run in the T4 wind tunnel using a 3 m horizontal axis machine and a 2.5 m Darrieus. Attention is given to modeling the structural dynamics and turbulent flow structures encountered by wind turbines. Experimental results relating windspeed, angle of attack, and output are presented. Optimization studies have indicated that wind farms will require a 6-7 blade diameter unit spacing to maintain satisfactory group output efficiencies.

  3. Simulator study of the effectiveness of an automatic control system designed to improve the high-angle-of-attack characteristics of a fighter airplane

    NASA Technical Reports Server (NTRS)

    Gilbert, W. P.; Nguyen, L. T.; Vangunst, R. W.

    1976-01-01

    A piloted, fixed-base simulation was conducted to study the effectiveness of some automatic control system features designed to improve the stability and control characteristics of fighter airplanes at high angles of attack. These features include an angle-of-attack limiter, a normal-acceleration limiter, an aileron-rudder interconnect, and a stability-axis yaw damper. The study was based on a current lightweight fighter prototype. The aerodynamic data used in the simulation were measured on a 0.15-scale model at low Reynolds number and low subsonic Mach number. The simulation was conducted on the Langley differential maneuvering simulator, and the evaluation involved representative combat maneuvering. Results of the investigation show the fully augmented airplane to be quite stable and maneuverable throughout the operational angle-of-attack range. The angle-of-attack/normal-acceleration limiting feature of the pitch control system is found to be a necessity to avoid angle-of-attack excursions at high angles of attack. The aileron-rudder interconnect system is shown to be very effective in making the airplane departure resistant while the stability-axis yaw damper provided improved high-angle-of-attack roll performance with a minimum of sideslip excursions.

  4. RApid Primary care Initiation of Drug treatment for Transient Ischaemic Attack (RAPID-TIA): study protocol for a pilot randomised controlled trial.

    PubMed

    Edwards, Duncan; Fletcher, Kate; Deller, Rachel; McManus, Richard; Lasserson, Daniel; Giles, Matthew; Sims, Don; Norrie, John; McGuire, Graham; Cohn, Simon; Whittle, Fiona; Hobbs, Vikki; Weir, Christopher; Mant, Jonathan

    2013-07-02

    People who have a transient ischaemic attack (TIA) or minor stroke are at high risk of a recurrent stroke, particularly in the first week after the event. Early initiation of secondary prevention drugs is associated with an 80% reduction in risk of stroke recurrence. This raises the question as to whether these drugs should be given before being seen by a specialist--that is, in primary care or in the emergency department. The aims of the RAPID-TIA pilot trial are to determine the feasibility of a randomised controlled trial, to analyse cost effectiveness and to ask: Should general practitioners and emergency doctors (primary care physicians) initiate secondary preventative measures in addition to aspirin in people they see with suspected TIA or minor stroke at the time of referral to a specialist? This is a pilot randomised controlled trial with a sub-study of accuracy of primary care physician diagnosis of TIA. In the pilot trial, we aim to recruit 100 patients from 30 general practices (including out-of-hours general practice centres) and 1 emergency department whom the primary care physician diagnoses with TIA or minor stroke and randomly assign them to usual care (that is, initiation of aspirin and referral to a TIA clinic) or usual care plus additional early initiation of secondary prevention drugs (a blood-pressure lowering protocol, simvastatin 40 mg and dipyridamole 200 mg m/r bd). The primary outcome of the main study will be the number of strokes at 90 days. The diagnostic accuracy sub-study will include these 100 patients and an additional 70 patients in whom the primary care physician thinks the diagnosis of TIA is possible, rather than probable. For the pilot trial, we will report recruitment rate, follow-up rate, a preliminary estimate of the primary event rate and occurrence of any adverse events. For the diagnostic study, we will calculate sensitivity and specificity of primary care physician diagnosis using the final TIA clinic diagnosis as the reference standard. This pilot study will be used to estimate key parameters that are needed to design the main study and to estimate the accuracy of primary care diagnosis of TIA. The planned follow-on trial will have important implications for the initial management of people with suspected TIA. ISRCTN62019087.

  5. Pediatric migraine.

    PubMed

    Shah, Ubaid Hameed; Kalra, Veena

    2009-01-01

    Migraine is the most common cause of acute recurrent headaches in children. The pathophysiological concepts have evolved from a purely vascular etiology to a neuroinflammatory process. Clinical evaluation is the mainstay of diagnosis and should also include family history. Investigations help to rule out secondary causes. The role of new drugs in treatment of migraine is discussed and trials are quoted from literature. Indications for starting prophylaxis should be evaluated based on frequency of attacks and influence on quality of life. For management of acute attacks of migraine both acetaminophen and ibuprofen are recommended for use in children. Many drugs like antiepileptic drugs (AED), calcium channel blockers, and antidepressants have been used for prophylaxis of migraine in children. The data for use of newer drugs for migraine in children is limited, though AEDs are emerging a popular choice. Biofeedback and other nonmedicinal therapies are being used with promising results.

  6. Cluster headache: present and future therapy.

    PubMed

    Leone, Massimo; Giustiniani, Alessandro; Cecchini, Alberto Proietti

    2017-05-01

    Cluster headache is characterized by severe, unilateral headache attacks of orbital, supraorbital or temporal pain lasting 15-180 min accompanied by ipsilateral lacrimation, rhinorrhea and other cranial autonomic manifestations. Cluster headache attacks need fast-acting abortive agents because the pain peaks very quickly; sumatriptan injection is the gold standard acute treatment. First-line preventative drugs include verapamil and carbolithium. Other drugs demonstrated effective in open trials include topiramate, valproic acid, gabapentin and others. Steroids are very effective; local injection in the occipital area is also effective but its prolonged use needs caution. Monoclonal antibodies against calcitonin gene-related peptide are under investigation as prophylactic agents in both episodic and chronic cluster headache. A number of neurostimulation procedures including occipital nerve stimulation, vagus nerve stimulation, sphenopalatine ganglion stimulation and the more invasive hypothalamic stimulation are employed in chronic intractable cluster headache.

  7. Music Regulators in Two String Quartets: A Comparison of Communicative Behaviors between Low- and High-Stress Performance Conditions.

    PubMed

    Biasutti, Michele; Concina, Eleonora; Wasley, David; Williamon, Aaron

    2016-01-01

    In ensemble performances, group members use particular bodily behaviors as a sort of "language" to supplement the lack of verbal communication. This article focuses on music regulators, which are defined as signs to other group members for coordinating performance. The following two music regulators are considered: body gestures for articulating attacks (a set of movements externally directed that are used to signal entrances in performance) and eye contact. These regulators are recurring observable behaviors that play an important role in non-verbal communication among ensemble members. To understand how they are used by chamber musicians, video recordings of two string quartet performances (Quartet A performing Bartók and Quartet B performing Haydn) were analyzed under two conditions: a low stress performance (LSP), undertaken in a rehearsal setting, and a high stress performance (HSP) during a public recital. The results provide evidence for more emphasis in gestures for articulating attacks (i.e., the perceived strength of a performed attack-type body gesture) during HSP than LSP. Conversely, no significant differences were found for the frequency of eye contact between HSP and LSP. Moreover, there was variability in eye contact during HSP and LSP, showing that these behaviors are less standardized and may change according to idiosyncratic performance conditions. Educational implications are discussed for improving interpersonal communication skills during ensemble performance.

  8. Music Regulators in Two String Quartets: A Comparison of Communicative Behaviors between Low- and High-Stress Performance Conditions

    PubMed Central

    Biasutti, Michele; Concina, Eleonora; Wasley, David; Williamon, Aaron

    2016-01-01

    In ensemble performances, group members use particular bodily behaviors as a sort of “language” to supplement the lack of verbal communication. This article focuses on music regulators, which are defined as signs to other group members for coordinating performance. The following two music regulators are considered: body gestures for articulating attacks (a set of movements externally directed that are used to signal entrances in performance) and eye contact. These regulators are recurring observable behaviors that play an important role in non-verbal communication among ensemble members. To understand how they are used by chamber musicians, video recordings of two string quartet performances (Quartet A performing Bartók and Quartet B performing Haydn) were analyzed under two conditions: a low stress performance (LSP), undertaken in a rehearsal setting, and a high stress performance (HSP) during a public recital. The results provide evidence for more emphasis in gestures for articulating attacks (i.e., the perceived strength of a performed attack-type body gesture) during HSP than LSP. Conversely, no significant differences were found for the frequency of eye contact between HSP and LSP. Moreover, there was variability in eye contact during HSP and LSP, showing that these behaviors are less standardized and may change according to idiosyncratic performance conditions. Educational implications are discussed for improving interpersonal communication skills during ensemble performance. PMID:27610089

  9. Pathologic features of fatal shark attacks.

    PubMed

    Byard, R W; Gilbert, J D; Brown, K

    2000-09-01

    To examine the pattern of injuries in cases of fatal shark attack in South Australian waters, the authors examined the files of their institution for all cases of shark attack in which full autopsies had been performed over the past 25 years, from 1974 to 1998. Of the seven deaths attributed to shark attack during this period, full autopsies were performed in only two cases. In the remaining five cases, bodies either had not been found or were incomplete. Case 1 was a 27-year-old male surfer who had been attacked by a shark. At autopsy, the main areas of injury involved the right thigh, which displayed characteristic teeth marks, extensive soft tissue damage, and incision of the femoral artery. There were also incised wounds of the right wrist. Bony injury was minimal, and no shark teeth were recovered. Case 2 was a 26-year-old male diver who had been attacked by a shark. At autopsy, the main areas of injury involved the left thigh and lower leg, which displayed characteristic teeth marks, extensive soft tissue damage, and incised wounds of the femoral artery and vein. There was also soft tissue trauma to the left wrist, with transection of the radial artery and vein. Bony injury was minimal, and no shark teeth were recovered. In both cases, death resulted from exsanguination following a similar pattern of soft tissue and vascular damage to a leg and arm. This type of injury is in keeping with predator attack from underneath or behind, with the most severe injuries involving one leg. Less severe injuries to the arms may have occurred during the ensuing struggle. Reconstruction of the damaged limb in case 2 by sewing together skin, soft tissue, and muscle bundles not only revealed that no soft tissue was missing but also gave a clearer picture of the pattern of teeth marks, direction of the attack, and species of predator.

  10. The efficacy of cladribine tablets in CIS patients retrospectively assigned the diagnosis of MS using modern criteria: Results from the ORACLE-MS study.

    PubMed

    Freedman, Mark S; Leist, Thomas P; Comi, Giancarlo; Cree, Bruce Ac; Coyle, Patricia K; Hartung, Hans-Peter; Vermersch, Patrick; Damian, Doris; Dangond, Fernando

    2017-01-01

    Multiple sclerosis (MS) diagnostic criteria have changed since the ORACLE-MS study was conducted; 223 of 616 patients (36.2%) would have met the diagnosis of MS vs clinically isolated syndrome (CIS) using the newer criteria. The objective of this paper is to assess the effect of cladribine tablets in patients with a first clinical demyelinating attack fulfilling newer criteria (McDonald 2010) for MS vs CIS. A post hoc analysis for subgroups of patients retrospectively classified as fulfilling or not fulfilling newer criteria at the first clinical demyelinating attack was conducted. Cladribine tablets 3.5 mg/kg ( n  = 68) reduced the risk of next attack or three-month confirmed Expanded Disability Status Scale (EDSS) worsening by 74% vs placebo ( n  = 72); p  = 0.0009 in patients meeting newer criteria for MS at baseline. Cladribine tablets 5.25 mg/kg ( n  = 83) reduced the risk of next attack or three-month confirmed EDSS worsening by 37%, but nominal significance was not reached ( p  = 0.14). In patients who were still CIS after applying newer criteria, cladribine tablets 3.5 mg/kg ( n  = 138) reduced the risk of conversion to clinically definite multiple sclerosis (CDMS) by 63% vs placebo ( n  = 134); p  = 0.0003. Cladribine tablets 5.25 mg/kg ( n  = 121) reduced the risk of conversion by 75% vs placebo ( n  = 134); p  < 0.0001. Regardless of the criteria used to define CIS or MS, 3.5 mg/kg cladribine tablets are effective in patients with a first clinical demyelinating attack. ClinicalTrials.gov registration: The ORACLE-MS study (NCT00725985).

  11. Nonpainful remote electrical stimulation alleviates episodic migraine pain.

    PubMed

    Yarnitsky, David; Volokh, Lana; Ironi, Alon; Weller, Boaz; Shor, Merav; Shifrin, Alla; Granovsky, Yelena

    2017-03-28

    To evaluate the efficacy of remote nonpainful electrical upper arm skin stimulation in reducing migraine attack pain. This is a prospective, double-blinded, randomized, crossover, sham-controlled trial. Migraineurs applied skin electrodes to the upper arm soon after attack onset for 20 minutes, at various pulse widths, and refrained from medications for 2 hours. Patients were asked to use the device for up to 20 attacks. In 71 patients (299 treatments) with evaluable data, 50% pain reduction was obtained for 64% of participants based on best of 200-μs, 150-μs, and 100-μs pulse width stimuli per individual vs 26% for sham stimuli. Greater pain reduction was found for active stimulation vs placebo; for those starting at severe or moderate pain, reduction (1) to mild or no pain occurred in 58% (25/43) of participants (66/134 treatments) for the 200-μs stimulation protocol and 24% (4/17; 8/29 treatments) for placebo ( p = 0.02), and (2) to no pain occurred in 30% (13/43) of participants (37/134 treatments) and 6% (1/17; 5/29 treatments), respectively ( p = 0.004). Earlier application of the treatment, within 20 minutes of attack onset, yielded better results: 46.7% pain reduction as opposed to 24.9% reduction when started later ( p = 0.02). Nonpainful remote skin stimulation can significantly reduce migraine pain, especially when applied early in an attack. This is presumably by activating descending inhibition pathways via the conditioned pain modulation effect. This treatment may be proposed as an attractive nonpharmacologic, easy to use, adverse event free, and inexpensive tool to reduce migraine pain. NCT02453399. This study provides Class III evidence that for patients with an acute migraine headache, remote nonpainful electrical stimulation on the upper arm skin reduces migraine pain. © 2017 American Academy of Neurology.

  12. Is the long-term prognosis of transient ischemic attack or minor ischemic stroke affected by the occurrence of nonfocal symptoms?

    PubMed

    Compter, Annette; van der Worp, H Bart; van Gijn, Jan; Kappelle, L Jaap; Koudstaal, Peter J; Algra, Ale

    2014-05-01

    In patients with a transient ischemic attack or ischemic stroke, nonfocal neurological symptoms, such as confusion and nonrotatory dizziness, may be associated with a higher risk of vascular events. We assessed the relationship between nonfocal symptoms and the long-term risk of vascular events or death in patients with a transient ischemic attack or minor ischemic stroke. We related initial symptoms with outcome events in 2409 patients with a transient ischemic attack (n=723) or minor ischemic stroke (n=1686), included in the Life Long After Cerebral ischemia cohort. All patients underwent a standardized interview on the occurrence of focal and nonfocal neurological symptoms during the qualifying event. The primary outcome was the composite of any stroke, myocardial infarction, or vascular death. Secondary outcomes were all-cause death, vascular death, cardiac death, myocardial infarction, and stroke. Hazard ratios were calculated with Cox regression. Focal symptoms were accompanied by nonfocal symptoms in 739 (31%) patients. During a mean follow-up of 10.1 years, the primary outcome occurred in 1313 (55%) patients. There was no difference in the risk of the primary outcome between patients with both focal and nonfocal symptoms and patients with focal symptoms alone (adjusted hazard ratio, 0.97; 95% confidence interval, 0.86-1.09; P=0.60). The risk of each of the secondary outcomes was also similar in both groups. About one third of the patients with a transient ischemic attack or minor ischemic stroke has both focal and nonfocal neurological symptoms. Nonfocal symptoms are not associated with an increased long-term risk of vascular events or death. This trial was not registered because enrollment began before July 1, 2005.

  13. A case of hereditary angioneurotic oedema, successfully treated with ε-aminocaproic acid. Studies on C'1 esterase inhibitor, C'1 activation, plasminogen level and histamine metabolism

    PubMed Central

    Lundh, B.; Laurell, Anna-Brita; Wetterqvist, H.; White, T.; Granerus, G.

    1968-01-01

    A patient with clinical and laboratory findings characteristic of hereditary angioneurotic oedema was investigated. The patient was observed for a period of 5 weeks, during which he had four attacks. ε-Aminocaproic acid (EACA) was then given continuously for 5 months, during which time the patient had no attacks. Attacks reappeared on withdrawal of EACA. Trans-4-(aminomethyl) cyclohexane carboxylic acid (AMCA®) was found to be equally effective in later therapeutic trials. C'1 esterase inhibitor was found in low concentration in defibrinated plasma also during attacks. ε-Aminocaproic acid (EACA) produced no significant change of the inhibitor content. C'1 esterase inhibitor disappeared on incubation of defibrinated plasma from the patient at 37°C for 40 min, and C'1 esterase was generated. The generation time of C'1 esterase increased with increasing the concentration of EDTA in the test solution. The C'1 esterase inhibitor content of defibrinated plasma from the patient, varied with the C'1 esterase generation time, the coefficient of correlation being higher in plasma sampled before treatment with EACA. Plasminogen and α2-macroglobulin were within the normal ranges, also during attacks. EACA markedly depressed the plasminogen level, which rapidly returned to normal on withdrawal of the drug. The studies on histamine metabolism revealed no significant changes with the exception of the urinary excretion of histamine, which was moderately increased towards the end of the period studied. On the days the patient received EACA the urine never contained 1-methylimidazole-5-acetic acid which was present in all the other specimens of urine examined. The basal gastric acid secretion was increased. PMID:5701955

  14. Characteristics of menstrual vs nonmenstrual migraine: a post hoc, within-woman analysis of the usual-care phase of a nonrandomized menstrual migraine clinical trial.

    PubMed

    MacGregor, E Anne; Victor, Timothy W; Hu, Xiaojun; Xiang, Qinfang; Puenpatom, Rajitkanok A; Chen, Wei; Campbell, John C

    2010-04-01

    To compare, using a within-woman analysis, the severity, duration, and relapse of menstrual vs nonmenstrual episodes of migraine during treatment with usual migraine therapy. Studies comparing the clinical characteristics of menstrual and nonmenstrual migraine attacks have yielded conflicting results, contributing to disagreement regarding whether menstrual migraine attacks are clinically more problematic than nonmenstrual migraine attacks. Post hoc within-woman analysis of the usual-care phase (month 1) of a 2-month, multicenter, prospective, open-label study at 21 US medical practices (predominantly primary care). Participants were women > or =18 years of age with regular predictable menstrual cycles (28 +/- 4 days) who self-reported a > or =1-year history of migraine attacks occurring between days -2 and +3 (menses onset = day +1) and > or =8 such attacks within the previous 12 cycles. Migraine treatment episodes were categorized as menstrual (occurring on days -2 to +3 of menses) or nonmenstrual (occurring on days +4 to -3 of menses). Pain severity, functional impairment, duration, relapse in 24 hours, and use of rescue medication were compared. Sources of variability (within- or between-patient) were determined using mathematical modeling. The http://www.clinicaltrial.gov code for trial is NCT00904098. Women (n = 153; intent to treat) reported 212 menstrual (59.2%) and 146 nonmenstrual (40.8%) migraine treatment episodes. Compared with nonmenstrual treatment episodes, menstrual episodes were more likely to cause impairment (unadjusted odds ratio, 1.65, 95% CI, 1.05-2.60; P = .03), were longer (unadjusted hazard ratio 1.68; 95% CI, 1.31-2.16; P < .001), and were more likely to relapse within 24 hours (unadjusted odds ratio, 2.66; 95% CI, 1.25-5.68; P = .01). Within-patient effects accounted for only 18-33% of the total variance in these outcomes. Post hoc, within-woman analysis of migraine treatment episodes categorized based on International Headache Society criteria showed that menstrual treatment episodes were more impairing, longer lasting, and more likely to relapse than nonmenstrual treatment episodes in this selected population of women with frequent menstrual migraine. The current analysis indicates that most of the variability in these outcomes is due to differences between headache types and not within-patient differences for a given type of headache, suggesting that menstrual episodes are potentially treatable. These findings underscore the differences between menstrual and nonmenstrual episodes of migraine and the need to offer effective migraine treatment to women.

  15. An Overview of Controls and Flying Qualities Technology on the F/A-18 High Alpha Research Vehicle

    NASA Technical Reports Server (NTRS)

    Pahle, Joseph W.; Wichman, Keith D.; Foster, John V.; Bundick, W. Thomas

    1996-01-01

    The NASA F/A-18 High Alpha Research Vehicle (HARV) has been the flight test bed of a focused technology effort to significantly increase maneuvering capability at high angles of attack. Development and flight test of control law design methodologies, handling qualities metrics, performance guidelines, and flight evaluation maneuvers are described. The HARV has been modified to include two research control effectors, thrust vectoring, and actuated forebody strakes in order to provide increased control power at high angles of attack. A research flight control system has been used to provide a flexible, easily modified capability for high-angle-of-attack research controls. Different control law design techniques have been implemented and flight-tested, including eigenstructure assignment, variable gain output feedback, pseudo controls, and model-following. Extensive piloted simulation has been used to develop nonlinear performance guide-lines and handling qualities criteria for high angles of attack. This paper reviews the development and evaluation of technologies useful for high-angle-of-attack control. Design, development, and flight test of the research flight control system, control laws, flying qualities specifications, and flight test maneuvers are described. Flight test results are used to illustrate some of the lessons learned during flight test and handling qualities evaluations.

  16. Consensus-Based Cooperative Spectrum Sensing with Improved Robustness Against SSDF Attacks

    NASA Astrophysics Data System (ADS)

    Liu, Quan; Gao, Jun; Guo, Yunwei; Liu, Siyang

    2011-05-01

    Based on the consensus algorithm, an attack-proof cooperative spectrum sensing (CSS) scheme is presented for decentralized cognitive radio networks (CRNs), where a common fusion center is not available and some malicious users may launch attacks with spectrum sensing data falsification (SSDF). Local energy detection is firstly performed by each secondary user (SU), and then, utilizing the consensus notions, each SU can make its own decision individually only by local information exchange with its neighbors rather than any centralized fusion used in most existing schemes. With the help of some anti-attack tricks, each authentic SU can generally identify and exclude those malicious reports during the interactions within the neighborhood. Compared with the existing solutions, the proposed scheme is proved to have much better robustness against three categories of SSDF attack, without requiring any a priori knowledge of the whole network.

  17. Mathematical Simulation of Perturbations of Attack Angle of Asymmetric Nanosatellite Passing through Resonance

    NASA Astrophysics Data System (ADS)

    Lyubimov, V. V.; Kurkina, E. V.

    2018-05-01

    The authors consider the problem of a dynamic system passing through a low-order resonance, describing an uncontrolled atmospheric descent of an asymmetric nanosatellite in the Earth's atmosphere. The authors perform mathematical and numerical modeling of the motion of the nanosatellite with a small mass-aerodynamic asymmetry relative to the center of mass. The aim of the study is to obtain new reliable approximate analytical estimates of perturbations of the angle of attack of a nanosatellite passing through resonance at angles of attack of not more than 0.5π. By using the stationary phase method, the authors were able to investigate a discontinuous perturbation in the angle of attack of a nanosatellite passing through a resonance with two different nanosatellite designs. Comparison of the results of the numerical modeling and new approximate analytical estimates of the perturbation of the angle of attack confirms the reliability of the said estimates.

  18. Hydrogen attack in Cr-Mo steels. [3Cr-1. 5Mo and 2. 25Cr-1Mo steels

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ruoff, S.; Stone, D.; Wanagel, J.

    Experiments conducted upon 3Cr-1.5Mo steel at elevated temperatures (600 C), and high pressure hydrogen (2000 psi), have shown a greater resistence to hydrogen attack compared with similar studies of 2.25Cr-lMo steels. Hydrogen exposure tests with and without an applied stress have been performed on both types of steels. Results of similar conditions show clear evidence of hydrogen attack in 2.25Cr-lMo steel, however, for the 3Cr-1.5Mo steel with exposure time up to 80 days without an applied stress no evidence of hydrogen attack is observed. For stress-rupture tests using stresses of 14 and 16 ksi, the 3Cr-1.5Mo steel showed no effectsmore » of hydrogen attack, and no damage was observed using a SEM.« less

  19. An efficient collaborative approach for black hole attack discovery and mitigating its impact in manet

    NASA Astrophysics Data System (ADS)

    Devipriya, K.; Ivy, B. Persis Urbana; Prabha, D.

    2018-04-01

    A mobile ad hoc network (MANET) is an assemblage of nodes composed of mobile devices coupled in various ways wirelessly which do not have any central administration. Each node in MANET cooperates in forwarding packets in the network. This type of collaboration incurs high cost but there exits nodes that declines to cooperate leading to selfish conduct of nodes which effects overall network performance. To discover the attacks caused by such nodes, a renowned mechanism using watchdog can be deployed. In infrastructure less network attack detection and reaction and high false positives, false negatives initiating black hole attack becomes major issue in watchdog. This paper put forward a collaborative approach for identifying such attacks in MANET. Through abstract analysis and extensive simulation of this approach, the detection time of misbehaved nodes is reduced and substantial enhancement in overhead and throughput is witnessed.

  20. Social Sentiment Sensor in Twitter for Predicting Cyber-Attacks Using ℓ1 Regularization

    PubMed Central

    Sanchez-Perez, Gabriel; Toscano-Medina, Karina; Martinez-Hernandez, Victor; Olivares-Mercado, Jesus; Sanchez, Victor

    2018-01-01

    In recent years, online social media information has been the subject of study in several data science fields due to its impact on users as a communication and expression channel. Data gathered from online platforms such as Twitter has the potential to facilitate research over social phenomena based on sentiment analysis, which usually employs Natural Language Processing and Machine Learning techniques to interpret sentimental tendencies related to users’ opinions and make predictions about real events. Cyber-attacks are not isolated from opinion subjectivity on online social networks. Various security attacks are performed by hacker activists motivated by reactions from polemic social events. In this paper, a methodology for tracking social data that can trigger cyber-attacks is developed. Our main contribution lies in the monthly prediction of tweets with content related to security attacks and the incidents detected based on ℓ1 regularization. PMID:29710833

  1. Reset Tree-Based Optical Fault Detection

    PubMed Central

    Lee, Dong-Geon; Choi, Dooho; Seo, Jungtaek; Kim, Howon

    2013-01-01

    In this paper, we present a new reset tree-based scheme to protect cryptographic hardware against optical fault injection attacks. As one of the most powerful invasive attacks on cryptographic hardware, optical fault attacks cause semiconductors to misbehave by injecting high-energy light into a decapped integrated circuit. The contaminated result from the affected chip is then used to reveal secret information, such as a key, from the cryptographic hardware. Since the advent of such attacks, various countermeasures have been proposed. Although most of these countermeasures are strong, there is still the possibility of attack. In this paper, we present a novel optical fault detection scheme that utilizes the buffers on a circuit's reset signal tree as a fault detection sensor. To evaluate our proposal, we model radiation-induced currents into circuit components and perform a SPICE simulation. The proposed scheme is expected to be used as a supplemental security tool. PMID:23698267

  2. Social Sentiment Sensor in Twitter for Predicting Cyber-Attacks Using ℓ₁ Regularization.

    PubMed

    Hernandez-Suarez, Aldo; Sanchez-Perez, Gabriel; Toscano-Medina, Karina; Martinez-Hernandez, Victor; Perez-Meana, Hector; Olivares-Mercado, Jesus; Sanchez, Victor

    2018-04-29

    In recent years, online social media information has been the subject of study in several data science fields due to its impact on users as a communication and expression channel. Data gathered from online platforms such as Twitter has the potential to facilitate research over social phenomena based on sentiment analysis, which usually employs Natural Language Processing and Machine Learning techniques to interpret sentimental tendencies related to users’ opinions and make predictions about real events. Cyber-attacks are not isolated from opinion subjectivity on online social networks. Various security attacks are performed by hacker activists motivated by reactions from polemic social events. In this paper, a methodology for tracking social data that can trigger cyber-attacks is developed. Our main contribution lies in the monthly prediction of tweets with content related to security attacks and the incidents detected based on ℓ 1 regularization.

  3. A performance study of unmanned aerial vehicle-based sensor networks under cyber attack

    NASA Astrophysics Data System (ADS)

    Puchaty, Ethan M.

    In UAV-based sensor networks, an emerging area of interest is the performance of these networks under cyber attack. This study seeks to evaluate the performance trade-offs from a System-of-Systems (SoS) perspective between various UAV communications architecture options in the context two missions: tracking ballistic missiles and tracking insurgents. An agent-based discrete event simulation is used to model a sensor communication network consisting of UAVs, military communications satellites, ground relay stations, and a mission control center. Network susceptibility to cyber attack is modeled with probabilistic failures and induced data variability, with performance metrics focusing on information availability, latency, and trustworthiness. Results demonstrated that using UAVs as routers increased network availability with a minimal latency penalty and communications satellite networks were best for long distance operations. Redundancy in the number of links between communication nodes helped mitigate cyber-caused link failures and add robustness in cases of induced data variability by an adversary. However, when failures were not independent, redundancy and UAV routing were detrimental in some cases to network performance. Sensitivity studies indicated that long cyber-caused downtimes and increasing failure dependencies resulted in build-ups of failures and caused significant degradations in network performance.

  4. Heart rate as a predictor of stroke in high-risk, hypertensive patients with previous stroke or transient ischemic attack.

    PubMed

    Sandset, Else Charlotte; Berge, Eivind; Kjeldsen, Sverre E; Julius, Stevo; Holzhauer, Björn; Krarup, Lars-Henrik; Hua, Tsushung A

    2014-01-01

    Risk factors for first stroke are well established, but less is known about risk factors for recurrent stroke. In the present analysis, we aimed to assess the effect of heart rate and other possible predictors of stroke in a hypertensive population with previous stroke or transient ischemic attack (TIA). The Valsartan Antihypertensive Long-Term Use Evaluation trial was a multicentre, double-masked, randomized controlled, parallel group trial comparing the effects of an angiotensin receptor blocker (valsartan) and a calcium channel blocker (amlodipine) in patients with hypertension and high cardiovascular risk. We used Cox proportional hazard models to investigate the effect of baseline variables on the risk of stroke. Quadratic terms of the continuous variables were entered in the models to test for linearity. Of 15,245 patients included in the trial, 3014 had a previous stroke or TIA at baseline and were included in the present analysis. Stroke recurrence occurred in 239 patients (7.9%) during a median of 4.5 years of follow-up. Resting heart rate (per 10 beats per minute; hazard ratio [HR], 2.78; 95% confidence interval [CI], 1.18-6.58) and diabetes mellitus at baseline (HR, 1.47; 95% CI, 1.03-2.10) were significantly associated with an increased risk of stroke recurrence in the multivariable analysis. In high-risk, hypertensive patients with previous stroke or TIA, resting heart rate was the strongest predictor of recurrent stroke. Copyright © 2014 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  5. Localization-Free Detection of Replica Node Attacks in Wireless Sensor Networks Using Similarity Estimation with Group Deployment Knowledge

    PubMed Central

    Ding, Chao; Yang, Lijun; Wu, Meng

    2017-01-01

    Due to the unattended nature and poor security guarantee of the wireless sensor networks (WSNs), adversaries can easily make replicas of compromised nodes, and place them throughout the network to launch various types of attacks. Such an attack is dangerous because it enables the adversaries to control large numbers of nodes and extend the damage of attacks to most of the network with quite limited cost. To stop the node replica attack, we propose a location similarity-based detection scheme using deployment knowledge. Compared with prior solutions, our scheme provides extra functionalities that prevent replicas from generating false location claims without deploying resource-consuming localization techniques on the resource-constraint sensor nodes. We evaluate the security performance of our proposal under different attack strategies through heuristic analysis, and show that our scheme achieves secure and robust replica detection by increasing the cost of node replication. Additionally, we evaluate the impact of network environment on the proposed scheme through theoretic analysis and simulation experiments, and indicate that our scheme achieves effectiveness and efficiency with substantially lower communication, computational, and storage overhead than prior works under different situations and attack strategies. PMID:28098846

  6. Localization-Free Detection of Replica Node Attacks in Wireless Sensor Networks Using Similarity Estimation with Group Deployment Knowledge.

    PubMed

    Ding, Chao; Yang, Lijun; Wu, Meng

    2017-01-15

    Due to the unattended nature and poor security guarantee of the wireless sensor networks (WSNs), adversaries can easily make replicas of compromised nodes, and place them throughout the network to launch various types of attacks. Such an attack is dangerous because it enables the adversaries to control large numbers of nodes and extend the damage of attacks to most of the network with quite limited cost. To stop the node replica attack, we propose a location similarity-based detection scheme using deployment knowledge. Compared with prior solutions, our scheme provides extra functionalities that prevent replicas from generating false location claims without deploying resource-consuming localization techniques on the resource-constraint sensor nodes. We evaluate the security performance of our proposal under different attack strategies through heuristic analysis, and show that our scheme achieves secure and robust replica detection by increasing the cost of node replication. Additionally, we evaluate the impact of network environment on the proposed scheme through theoretic analysis and simulation experiments, and indicate that our scheme achieves effectiveness and efficiency with substantially lower communication, computational, and storage overhead than prior works under different situations and attack strategies.

  7. Human Vaccines & Immunotherapeutics

    PubMed Central

    Riedmann, Eva M.

    2012-01-01

    Two therapeutic HPV vaccine candidates successful in phase 1 Flu shot may prevent heart attacks and stroke CDX-1401 combined with TLR agonist: Positive phase 1 results Three MRSA vaccines in early clincial trials Ovarian cancer vaccine candidate DPX-Survivac: Positive interim results from phase 1 Chinese biotech partnership brings first hepatitis E vaccine to the market Therapeutic vaccine for treatment of genital herpes enters phase 2 Visionary concept: Printable vaccines PMID:23817319

  8. Annual Research Progress Report. Fiscal Year 2003. Volume’s 1 and 2

    DTIC Science & Technology

    2003-01-01

    transient ischemic attack, amaurosis fugax or stroke in the cerebral distribution of the operated side, 3) the occurrence of criteria for reoperation...Functional Severity and Recovery of Motor Limbs in Acute Brain Injury KEYWORDS: Stroke /Diagnostic assessment. PRINCIPAL INVESTIGATOR: LTC...A Randomized Trial. (1/16/2001) 02-86002 655Knapik, Joseph, PhD DAC. Injury Control and Running Footwear. (3/12/2002) CHPPM 02-98001E

  9. A School-Based, Teacher-Mediated Prevention Program (Erase-Stress) for Reducing Terror-Related Traumatic Reactions in Israeli Youth: A Quasi-Randomized Controlled Trial

    ERIC Educational Resources Information Center

    Gelkopf, Marc; Berger, Rony

    2009-01-01

    Background: Since September 2000 Israeli children have been exposed to a large number of terrorist attacks. A universal, school-based intervention for dealing with the threat of terrorism as well as with terror-related symptoms, ERASE-Stress (ES), was evaluated in a male religious middle school in southern Israel. The program was administered by…

  10. CTC Sentinel. Volume 5, Issue 10, October 2012

    DTIC Science & Technology

    2012-10-01

    of the tactical precision that helped establish the organization’s criminal brand: one that connotes fury, force, and fear.7 Trevino’s Limits Today ...formidable and secretive support network in the country since 2007.26 Pumwani Riyadha Mosque Today , there are a number of extremist support...research, he could not identify a single terrorist attack using the diluted fertilizer type available on European markets today . The trial also shed

  11. Association of global weather changes with acute coronary syndromes: gaining insights from clinical trials data

    NASA Astrophysics Data System (ADS)

    Bakal, Jeffrey A.; Ezekowitz, Justin A.; Westerhout, Cynthia M.; Boersma, Eric; Armstrong, Paul W.

    2013-05-01

    The aim of this study was to develop a method for the identification of global weather parameters and patient characteristics associated with a type of heart attack in which there is a sudden partial blockage of a coronary artery. This type of heart attack does not demonstrate an elevation of the ST segment on an electrocardiogram and is defined as a non-ST elevation acute coronary syndrome (NSTE-ACS). Data from the Global Summary of the Day database was linked with the enrollment and baseline data for a phase III international clinical trial in NSTE-ACS in four 48-h time periods covering the week prior to the clinical event that prompted enrollment in the study. Meteorological events were determined by standardizing the weather data from enrollment dates against an empirical distribution from the month prior. These meteorological events were then linked to the patients' geographic region, demographics and comorbidities to identify potential susceptible populations. After standardization, changes in temperature and humidity demonstrated an association with the enrollment event. Additionally there appeared to be an association with gender, region and a history of stroke. This methodology may provide a useful global insight into assessing the biometeorologic component of diseases from international data.

  12. Control definition study for advanced vehicles

    NASA Technical Reports Server (NTRS)

    Lapins, M.; Martorella, R. P.; Klein, R. W.; Meyer, R. C.; Sturm, M. J.

    1983-01-01

    The low speed, high angle of attack flight mechanics of an advanced, canard-configured, supersonic tactical aircraft designed with moderate longitudinal relaxed static stability (Static Margin, SM = 16% C sub W at M = 0.4) was investigated. Control laws were developed for the longitudinal axis (""G'' or maneuver and angle of attack command systems) and for the lateral/directional axes. The performance of these control laws was examined in engineering simulation. A canard deflection/rate requirement study was performed as part of the ""G'' command law evaluation at low angles of attack. Simulated coupled maneuvers revealed the need for command limiters in all three aircraft axes to prevent departure from controlled flight. When modified with command/maneuver limiters, the control laws were shown to be adequate to prevent aircraft departure during aggressive air combat maneuvering.

  13. Defense Against Chip Cloning Attacks Based on Fractional Hopfield Neural Networks.

    PubMed

    Pu, Yi-Fei; Yi, Zhang; Zhou, Ji-Liu

    2017-06-01

    This paper presents a state-of-the-art application of fractional hopfield neural networks (FHNNs) to defend against chip cloning attacks, and provides insight into the reason that the proposed method is superior to physically unclonable functions (PUFs). In the past decade, PUFs have been evolving as one of the best types of hardware security. However, the development of the PUFs has been somewhat limited by its implementation cost, its temperature variation effect, its electromagnetic interference effect, the amount of entropy in it, etc. Therefore, it is imperative to discover, through promising mathematical methods and physical modules, some novel mechanisms to overcome the aforementioned weaknesses of the PUFs. Motivated by this need, in this paper, we propose applying the FHNNs to defend against chip cloning attacks. At first, we implement the arbitrary-order fractor of a FHNN. Secondly, we describe the implementation cost of the FHNNs. Thirdly, we propose the achievement of the constant-order performance of a FHNN when ambient temperature varies. Fourthly, we analyze the electrical performance stability of the FHNNs under electromagnetic disturbance conditions. Fifthly, we study the amount of entropy of the FHNNs. Lastly, we perform experiments to analyze the pass-band width of the fractor of an arbitrary-order FHNN and the defense against chip cloning attacks capability of the FHNNs. In particular, the capabilities of defense against chip cloning attacks, anti-electromagnetic interference, and anti-temperature variation of a FHNN are illustrated experimentally in detail. Some significant advantages of the FHNNs are that their implementation cost is considerably lower than that of the PUFs, their electrical performance is much more stable than that of the PUFs under different temperature conditions, their electrical performance stability of the FHNNs under electromagnetic disturbance conditions is much more robust than that of the PUFs, and their amount of entropy is significantly higher than that of the PUFs with the same rank circuit scale.

  14. [Study on clinical effectiveness of acupuncture and moxibustion on acute Bell's facial paralysis: randomized controlled clinical observation].

    PubMed

    Wu, Bin; Li, Ning; Liu, Yi; Huang, Chang-qiong; Zhang, Yong-ling

    2006-03-01

    To investigate the adverse effects of acupuncture on the prognosis, and effectiveness of acupuncture combined with far infrared ray in the patient of acute Bell's facial paralysis within 48 h. Clinically randomized controlled trial was used, and the patients were divided into 3 groups: group A (early acupuncture group), group B (acupuncture combined with far infrared ray) and group C (acupuncture after 7 days). The facial nerve functional classification at the attack, 7 days after the attack and after treatment, the clinically cured rate of following-up of 6 months, and the average cured time, the cured time of complete facial paralysis were observed in the 3 groups. There were no significant differences among the 3 groups in the facial nerve functional classification 7 days after the attack, the clinically cured rate of following-up of 6 months and the average cured time (P > 0.05), but the cured time of complete facial paralysis in the group A and the group B were shorter than that in the group C (P < 0.05). The patient of acute Bell's facial paralysis can be treated with acupuncture and moxibustion, and traditional moxibustion can be replaced by far infrared way.

  15. Panic attack and its correlation with acute coronary syndrome - more than just a diagnosis of exclusion.

    PubMed

    Soh, Keng Chuan; Lee, Cheng

    2010-03-01

    The panic attack is able to mimic the clinical presentation of an acute coronary syndrome (ACS), to the point of being clinically indistinguishable without appropriate investigations. However, the literature actually demonstrates that the 2 conditions are more related than just being differential diagnoses. Through a review of the literature involving epidemiological studies, randomised controlled trials, systematic reviews and meta-analyses found on a Medline search, the relation between panic disorder and ACS is explored in greater depth. Panic disorder, a psychiatric condition with recurrent panic attacks, has been found to be an independent risk factor for subsequent coronary events. This has prognostic bearing and higher mortality rates. Through activation of the sympathetic system by differing upstream mechanisms, the 2 conditions have similar presentations. Another psychiatric differential diagnosis would be that of akathisia, as an adverse effect to antidepressant medications. An overview on the investigations, diagnostic process, treatment modalities and prognoses of the two conditions is presented. Panic disorders remain under-diagnosed, but various interviews are shown to allow physicians without psychiatric training to accurately pick up the condition. Comprehensive multidisciplinary approaches are needed to help patients with both coronary heart disease and anxiety disorder.

  16. Comparison between the efficacy of ginger and sumatriptan in the ablative treatment of the common migraine.

    PubMed

    Maghbooli, Mehdi; Golipour, Farhad; Moghimi Esfandabadi, Alireza; Yousefi, Mehran

    2014-03-01

    Frequency and torment caused by migraines direct patients toward a variety of remedies. Few studies to date have proposed ginger derivates for migraine relief. This study aims to evaluate the efficacy of ginger in the ablation of common migraine attack in comparison to sumatriptan therapy. In this double-blinded randomized clinical trial, 100 patients who had acute migraine without aura were randomly allocated to receive either ginger powder or sumatriptan. Time of headache onset, its severity, time interval from headache beginning to taking drug and patient self-estimation about response for five subsequent migraine attacks were recorded by patients. Patients(,) satisfaction from treatment efficacy and their willingness to continue it was also evaluated after 1 month following intervention. Two hours after using either drug, mean headaches severity decreased significantly. Efficacy of ginger powder and sumatriptan was similar. Clinical adverse effects of ginger powder were less than sumatriptan. Patients' satisfaction and willingness to continue did not differ. The effectiveness of ginger powder in the treatment of common migraine attacks is statistically comparable to sumatriptan. Ginger also poses a better side effect profile than sumatriptan. Copyright © 2013 John Wiley & Sons, Ltd.

  17. A robust color image watermarking algorithm against rotation attacks

    NASA Astrophysics Data System (ADS)

    Han, Shao-cheng; Yang, Jin-feng; Wang, Rui; Jia, Gui-min

    2018-01-01

    A robust digital watermarking algorithm is proposed based on quaternion wavelet transform (QWT) and discrete cosine transform (DCT) for copyright protection of color images. The luminance component Y of a host color image in YIQ space is decomposed by QWT, and then the coefficients of four low-frequency subbands are transformed by DCT. An original binary watermark scrambled by Arnold map and iterated sine chaotic system is embedded into the mid-frequency DCT coefficients of the subbands. In order to improve the performance of the proposed algorithm against rotation attacks, a rotation detection scheme is implemented before watermark extracting. The experimental results demonstrate that the proposed watermarking scheme shows strong robustness not only against common image processing attacks but also against arbitrary rotation attacks.

  18. Extended analysis of the Trojan-horse attack in quantum key distribution

    NASA Astrophysics Data System (ADS)

    Vinay, Scott E.; Kok, Pieter

    2018-04-01

    The discrete-variable quantum key distribution protocols based on the 1984 protocol of Bennett and Brassard (BB84) are known to be secure against an eavesdropper, Eve, intercepting the flying qubits and performing any quantum operation on them. However, these protocols may still be vulnerable to side-channel attacks. We investigate the Trojan-horse side-channel attack where Eve sends her own state into Alice's apparatus and measures the reflected state to estimate the key. We prove that the separable coherent state is optimal for Eve among the class of multimode Gaussian attack states, even in the presence of thermal noise. We then provide a bound on the secret key rate in the case where Eve may use any separable state.

  19. Aerodynamic characteristics of cruciform missiles at high angles of attack

    NASA Technical Reports Server (NTRS)

    Lesieutre, Daniel J.; Mendenhall, Michael R.; Nazario, Susana M.; Hemsch, Michael J.

    1987-01-01

    An aerodynamic prediction method for missile aerodynamic performance and preliminary design has been developed to utilize a newly available systematic fin data base and an improved equivalent angle of attack methodology. The method predicts total aerodynamic loads and individual fin forces and moments for body-tail (wing-body) and canard-body-tail configurations with cruciform fin arrangements. The data base and the prediction method are valid for angles of attack up to 45 deg, arbitrary roll angles, fin deflection angles between -40 deg and 40 deg, Mach numbers between 0.6 and 4.5, and fin aspect ratios between 0.25 and 4.0. The equivalent angle of attack concept is employed to include the effects of vorticity and geometric scaling.

  20. A Secured Authentication Protocol for SIP Using Elliptic Curves Cryptography

    NASA Astrophysics Data System (ADS)

    Chen, Tien-Ho; Yeh, Hsiu-Lien; Liu, Pin-Chuan; Hsiang, Han-Chen; Shih, Wei-Kuan

    Session initiation protocol (SIP) is a technology regularly performed in Internet Telephony, and Hyper Text Transport Protocol (HTTP) as digest authentication is one of the major methods for SIP authentication mechanism. In 2005, Yang et al. pointed out that HTTP could not resist server spoofing attack and off-line guessing attack and proposed a secret authentication with Diffie-Hellman concept. In 2009, Tsai proposed a nonce based authentication protocol for SIP. In this paper, we demonstrate that their protocol could not resist the password guessing attack and insider attack. Furthermore, we propose an ECC-based authentication mechanism to solve their issues and present security analysis of our protocol to show that ours is suitable for applications with higher security requirement.

  1. Continuous-Variable Measurement-Device-Independent Multipartite Quantum Communication Using Coherent States

    NASA Astrophysics Data System (ADS)

    Zhou, Jian; Guo, Ying

    2017-02-01

    A continuous-variable measurement-device-independent (CV-MDI) multipartite quantum communication protocol is designed to realize multipartite communication based on the GHZ state analysis using Gaussian coherent states. It can remove detector side attack as the multi-mode measurement is blindly done in a suitable Black Box. The entanglement-based CV-MDI multipartite communication scheme and the equivalent prepare-and-measurement scheme are proposed to analyze the security and guide experiment, respectively. The general eavesdropping and coherent attack are considered for the security analysis. Subsequently, all the attacks are ascribed to coherent attack against imperfect links. The asymptotic key rate of the asymmetric configuration is also derived with the numeric simulations illustrating the performance of the proposed protocol.

  2. A Secure Region-Based Geographic Routing Protocol (SRBGR) for Wireless Sensor Networks

    PubMed Central

    Adnan, Ali Idarous; Hanapi, Zurina Mohd; Othman, Mohamed; Zukarnain, Zuriati Ahmad

    2017-01-01

    Due to the lack of dependency for routing initiation and an inadequate allocated sextant on responding messages, the secure geographic routing protocols for Wireless Sensor Networks (WSNs) have attracted considerable attention. However, the existing protocols are more likely to drop packets when legitimate nodes fail to respond to the routing initiation messages while attackers in the allocated sextant manage to respond. Furthermore, these protocols are designed with inefficient collection window and inadequate verification criteria which may lead to a high number of attacker selections. To prevent the failure to find an appropriate relay node and undesirable packet retransmission, this paper presents Secure Region-Based Geographic Routing Protocol (SRBGR) to increase the probability of selecting the appropriate relay node. By extending the allocated sextant and applying different message contention priorities more legitimate nodes can be admitted in the routing process. Moreover, the paper also proposed the bound collection window for a sufficient collection time and verification cost for both attacker identification and isolation. Extensive simulation experiments have been performed to evaluate the performance of the proposed protocol in comparison with other existing protocols. The results demonstrate that SRBGR increases network performance in terms of the packet delivery ratio and isolates attacks such as Sybil and Black hole. PMID:28121992

  3. A Secure Region-Based Geographic Routing Protocol (SRBGR) for Wireless Sensor Networks.

    PubMed

    Adnan, Ali Idarous; Hanapi, Zurina Mohd; Othman, Mohamed; Zukarnain, Zuriati Ahmad

    2017-01-01

    Due to the lack of dependency for routing initiation and an inadequate allocated sextant on responding messages, the secure geographic routing protocols for Wireless Sensor Networks (WSNs) have attracted considerable attention. However, the existing protocols are more likely to drop packets when legitimate nodes fail to respond to the routing initiation messages while attackers in the allocated sextant manage to respond. Furthermore, these protocols are designed with inefficient collection window and inadequate verification criteria which may lead to a high number of attacker selections. To prevent the failure to find an appropriate relay node and undesirable packet retransmission, this paper presents Secure Region-Based Geographic Routing Protocol (SRBGR) to increase the probability of selecting the appropriate relay node. By extending the allocated sextant and applying different message contention priorities more legitimate nodes can be admitted in the routing process. Moreover, the paper also proposed the bound collection window for a sufficient collection time and verification cost for both attacker identification and isolation. Extensive simulation experiments have been performed to evaluate the performance of the proposed protocol in comparison with other existing protocols. The results demonstrate that SRBGR increases network performance in terms of the packet delivery ratio and isolates attacks such as Sybil and Black hole.

  4. Validation and comparison of imaging-based scores for prediction of early stroke risk after transient ischaemic attack: a pooled analysis of individual-patient data from cohort studies.

    PubMed

    Kelly, Peter J; Albers, Gregory W; Chatzikonstantinou, Anastasios; De Marchis, Gian Marco; Ferrari, Julia; George, Paul; Katan, Mira; Knoflach, Michael; Kim, Jong S; Li, Linxin; Lee, Eun-Jae; Olivot, Jean-Marc; Purroy, Francisco; Raposo, Nicolas; Rothwell, Peter M; Sharma, Vijay K; Song, Bo; Tsivgoulis, Georgios; Walsh, Cathal; Xu, Yuming; Merwick, Aine

    2016-11-01

    Identification of patients at highest risk of early stroke after transient ischaemic attack has been improved with imaging based scores. We aimed to compare the validity and prognostic utility of imaging-based stroke risk scores in patients after transient ischaemic attack. We did a pooled analysis of published and unpublished individual-patient data from 16 cohort studies of transient ischaemic attack done in Asia, Europe, and the USA, with early brain and vascular imaging and follow up. All patients were assessed by stroke specialists in hospital settings as inpatients, in emergency departments, or in transient ischaemic attack clinics. Inclusion criteria were stroke-specialist confirmed transient ischaemic attack, age of 18 years or older, and MRI done within 7 days of index transient ischaemic attack and before stroke recurrence. Multivariable logistic regression was done to analyse the predictive utility of abnormal diffusion-weighted MRI, carotid stenosis, and transient ischaemic attack within 1 week of index transient ischaemic attack (dual transient ischaemic attack) after adjusting for ABCD2 score. We compared the prognostic utility of the ABCD2, ABCD2-I, and ABCD3-I scores using discrimination, calibration, and risk reclassification. In 2176 patients from 16 cohort studies done between 2005 and 2015, after adjusting for ABCD2 score, positive diffusion-weighted imaging (odds ratio [OR] 3·8, 95% CI 2·1-7·0), dual transient ischaemic attack (OR 3·3, 95% CI 1·8-5·8), and ipsilateral carotid stenosis (OR 4·7, 95% CI 2·6-8·6) were associated with 7 day stroke after index transient ischaemic attack (p<0·001 for all). 7 day stroke risk increased with increasing ABCD2-I and ABCD3-I scores (both p<0·001). Discrimination to identify early stroke risk was improved for ABCD2-I versus ABCD2 (2 day c statistic 0·74 vs 0·64; p=0·006). However, discrimination was further improved by ABCD3-I compared with ABCD2 (2 day c statistic 0·84 vs 0·64; p<0·001) and ABCD2-I (c statistic 0·84 vs 0·74; p<0·001). Early stroke risk reclassification was improved by ABCD3-I compared with ABCD2-I score (clinical net reclassification improvement 33% at 2 days). Although ABCD2-I and ABCD3-I showed validity, the ABCD3-I score reliably identified highest-risk patients at highest risk of a stroke after transient ischaemic attack with improved risk prediction compared with ABCD2-I. Transient ischaemic attack management guided by ABCD3-I with immediate stroke-specialist assessment, urgent MRI, and vascular imaging should now be considered, with monitoring of safety and cost-effectiveness. Health Research Board of Ireland, Irish Heart Foundation, Irish Health Service Executive, Irish National Lottery, National Medical Research Council of Singapore, Swiss National Science Foundation, Bangerter-Rhyner Foundation, Swiss National Science Foundation, Swisslife Jubiläumsstiftung for Medical Research, Swiss Neurological Society, Fondazione Dr Ettore Balli (Switzerland), Clinical Trial Unit of University of Bern, South Korea's Ministry for Health, Welfare, and Family Affairs, UK Wellcome Trust, Wolfson Foundation, UK Stroke Association, British Heart Foundation, Dunhill Medical Trust, National Institute of Health Research (NIHR), Medical Research Council, and the NIHR Oxford Biomedical Research Centre. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Major depressive disorder following terrorist attacks: A systematic review of prevalence, course and correlates

    PubMed Central

    2011-01-01

    Background Terrorist attacks are traumatic events that may result in a wide range of psychological disorders for people exposed. This review aimed to systematically assess the current evidence on major depressive disorder (MDD) after terrorist attacks. Methods A systematic review was performed. Studies included assessed the impact of human-made, intentional, terrorist attacks in direct victims and/or persons in general population and evaluated MDD based on diagnostic criteria. Results A total of 567 reports were identified, 11 of which were eligible for this review: 6 carried out with direct victims, 4 with persons in general population, and 1 with victims and general population. The reviewed literature suggests that the risk of MDD ranges between 20 and 30% in direct victims and between 4 and 10% in the general population in the first few months after terrorist attacks. Characteristics that tend to increase risk of MDD after a terrorist attack are female gender, having experienced more stressful situations before or after the attack, peritraumatic reactions during the attack, loss of psychosocial resources, and low social support. The course of MDD after terrorist attacks is less clear due to the scarcity of longitudinal studies. Conclusions Methodological limitations in the literature of this field are considered and potentially important areas for future research such as the assessment of the course of MDD, the study of correlates of MDD or the comorbidity between MDD and other mental health problems are discussed. PMID:21627850

  6. Message Integrity Model for Wireless Sensor Networks

    ERIC Educational Resources Information Center

    Qleibo, Haider W.

    2009-01-01

    WSNs are susceptible to a variety of attacks. These attacks vary in the way they are performed and executed; they include but not limited to node capture, physical tampering, denial of service, and message alteration. It is of paramount importance to protect gathered data by WSNs and defend the network against illegal access and malicious…

  7. A Game-Theoretic Response Strategy for Coordinator Attack in Wireless Sensor Networks

    PubMed Central

    Liu, Jianhua; Yue, Guangxue; Shang, Huiliang; Li, Hongjie

    2014-01-01

    The coordinator is a specific node that controls the whole network and has a significant impact on the performance in cooperative multihop ZigBee wireless sensor networks (ZWSNs). However, the malicious node attacks coordinator nodes in an effort to waste the resources and disrupt the operation of the network. Attacking leads to a failure of one round of communication between the source nodes and destination nodes. Coordinator selection is a technique that can considerably defend against attack and reduce the data delivery delay, and increase network performance of cooperative communications. In this paper, we propose an adaptive coordinator selection algorithm using game and fuzzy logic aiming at both minimizing the average number of hops and maximizing network lifetime. The proposed game model consists of two interrelated formulations: a stochastic game for dynamic defense and a best response policy using evolutionary game formulation for coordinator selection. The stable equilibrium best policy to response defense is obtained from this game model. It is shown that the proposed scheme can improve reliability and save energy during the network lifetime with respect to security. PMID:25105171

  8. A comparative analysis between NACA 4412 airfoil and it's modified form with tubercles

    NASA Astrophysics Data System (ADS)

    Hasan, Md. Jonayed; Islam, Md. Tazul; Hassan, Md. Mehedi

    2017-06-01

    The effect of tubercles on the leading edge of an airfoil become more vivid at high angle of attacks. The effect of tubercles with large wavelength and small amplitude on the leading edge of a NACA 4412 airfoil section was investigated numerically and experimentally. The phenomena of improving the airfoil performance by modifying the contours drove our interest to do this analysis. The models were developed & numerical simulations were carried out with both NACA 4412 airfoil and modified airfoil model at Re=1.03×106 and angles of attack ranging from 0° to 20°. Flow separation was analyzed with vector profiles. CL, CD at different angle of attacks was developed and it gave down noticeable pre-stall & post-stall behavior. The airfoils were studied experimentally in a low speed wind tunnel. Pressure distribution over the two airfoils was obtained. It was evident from the pressure distributions that the modified airfoil exhibits significant aerodynamic performance at high angles of attack. We can infer that these effects will be advantageous for maneuverability and post-stall behavior.

  9. A Secure Trust Establishment Scheme for Wireless Sensor Networks

    PubMed Central

    Ishmanov, Farruh; Kim, Sung Won; Nam, Seung Yeob

    2014-01-01

    Trust establishment is an important tool to improve cooperation and enhance security in wireless sensor networks. The core of trust establishment is trust estimation. If a trust estimation method is not robust against attack and misbehavior, the trust values produced will be meaningless, and system performance will be degraded. We present a novel trust estimation method that is robust against on-off attacks and persistent malicious behavior. Moreover, in order to aggregate recommendations securely, we propose using a modified one-step M-estimator scheme. The novelty of the proposed scheme arises from combining past misbehavior with current status in a comprehensive way. Specifically, we introduce an aggregated misbehavior component in trust estimation, which assists in detecting an on-off attack and persistent malicious behavior. In order to determine the current status of the node, we employ previous trust values and current measured misbehavior components. These components are combined to obtain a robust trust value. Theoretical analyses and evaluation results show that our scheme performs better than other trust schemes in terms of detecting an on-off attack and persistent misbehavior. PMID:24451471

  10. A game-theoretic response strategy for coordinator attack in wireless sensor networks.

    PubMed

    Liu, Jianhua; Yue, Guangxue; Shen, Shigen; Shang, Huiliang; Li, Hongjie

    2014-01-01

    The coordinator is a specific node that controls the whole network and has a significant impact on the performance in cooperative multihop ZigBee wireless sensor networks (ZWSNs). However, the malicious node attacks coordinator nodes in an effort to waste the resources and disrupt the operation of the network. Attacking leads to a failure of one round of communication between the source nodes and destination nodes. Coordinator selection is a technique that can considerably defend against attack and reduce the data delivery delay, and increase network performance of cooperative communications. In this paper, we propose an adaptive coordinator selection algorithm using game and fuzzy logic aiming at both minimizing the average number of hops and maximizing network lifetime. The proposed game model consists of two interrelated formulations: a stochastic game for dynamic defense and a best response policy using evolutionary game formulation for coordinator selection. The stable equilibrium best policy to response defense is obtained from this game model. It is shown that the proposed scheme can improve reliability and save energy during the network lifetime with respect to security.

  11. Subclinical endophthalmitis following a rooster attack.

    PubMed

    Lekse Kovach, Jaclyn; Maguluri, Srilakshmi; Recchia, Franco M

    2006-12-01

    Ocular injury resulting from rooster attacks is rarely reported in the literature. Sadly, the target of these attacks is most often children younger than 3 years old, whose naiveté of the aggressive, territorial behavior of birds can place them at risk. Acute sequelae of these attacks can result in a lifetime of visual impairment. The possibility of a subacute or occult infection is an unusual occurrence that must always be considered. In an effort to prevent future attacks and ocular casualties, we present a case of a 12-month-old boy who suffered an open globe following a rooster attack. The open globe was emergently repaired. One week later, a white cataract was noticed on examination in the absence of systemic or ocular signs of inflammation. Traumatic endophthalmitis and lenticular abscess were suspected during examination under anesthesia. Vitrectomy, lensectomy, and injection of intravitreal antibiotics were performed. Culture of lenticular and vitreous aspirates grew alpha-streptococcus. Alpha-streptococcal endophthalmitis can result from ocular injuries caused by rooster pecking. The infection may present insidiously and without typical ocular or systemic symptoms or signs. Management is challenging and may require surgery.

  12. Wind-tunnel investigation to determine the low speed yawing stability derivatives of a twin jet fighter model at high angles of attack

    NASA Technical Reports Server (NTRS)

    Coe, P. L., Jr.; Newsom, W. A., Jr.

    1974-01-01

    An investigation was conducted to determine the low-speed yawing stability derivatives of a twin-jet fighter airplane model at high angles of attack. Tests were performed in a low-speed tunnel utilizing variable-curvature walls to simulate pure yawing motion. The results of the study showed that at angles of attack below the stall the yawing derivatives were essentially independent of the yawing velocity and sideslip angle. However, at angles of attack above the stall some nonlinear variations were present and the derivatives were strongly dependent upon sideslip angle. The results also showed that the rolling moment due to yawing was primarily due to the wing-fuselage combination, and that at angles of attack below the stall both the vertical and horizontal tails produced significant contributions to the damping in yaw. Additionally, the tests showed that the use of the forced-oscillation data to represent the yawing stability derivatives is questionable, at high angles of attack, due to large effects arising from the acceleration in sideslip derivatives.

  13. Vulnerability analysis and critical areas identification of the power systems under terrorist attacks

    NASA Astrophysics Data System (ADS)

    Wang, Shuliang; Zhang, Jianhua; Zhao, Mingwei; Min, Xu

    2017-05-01

    This paper takes central China power grid (CCPG) as an example, and analyzes the vulnerability of the power systems under terrorist attacks. To simulate the intelligence of terrorist attacks, a method of critical attack area identification according to community structures is introduced. Meanwhile, three types of vulnerability models and the corresponding vulnerability metrics are given for comparative analysis. On this basis, influence of terrorist attacks on different critical areas is studied. Identifying the vulnerability of different critical areas will be conducted. At the same time, vulnerabilities of critical areas under different tolerance parameters and different vulnerability models are acquired and compared. Results show that only a few number of vertex disruptions may cause some critical areas collapse completely, they can generate great performance losses the whole systems. Further more, the variation of vulnerability values under different scenarios is very large. Critical areas which can cause greater damage under terrorist attacks should be given priority of protection to reduce vulnerability. The proposed method can be applied to analyze the vulnerability of other infrastructure systems, they can help decision makers search mitigation action and optimum protection strategy.

  14. Design of a Secure Authentication and Key Agreement Scheme Preserving User Privacy Usable in Telecare Medicine Information Systems.

    PubMed

    Arshad, Hamed; Rasoolzadegan, Abbas

    2016-11-01

    Authentication and key agreement schemes play a very important role in enhancing the level of security of telecare medicine information systems (TMISs). Recently, Amin and Biswas demonstrated that the authentication scheme proposed by Giri et al. is vulnerable to off-line password guessing attacks and privileged insider attacks and also does not provide user anonymity. They also proposed an improved authentication scheme, claiming that it resists various security attacks. However, this paper demonstrates that Amin and Biswas's scheme is defenseless against off-line password guessing attacks and replay attacks and also does not provide perfect forward secrecy. This paper also shows that Giri et al.'s scheme not only suffers from the weaknesses pointed out by Amin and Biswas, but it also is vulnerable to replay attacks and does not provide perfect forward secrecy. Moreover, this paper proposes a novel authentication and key agreement scheme to overcome the mentioned weaknesses. Security and performance analyses show that the proposed scheme not only overcomes the mentioned security weaknesses, but also is more efficient than the previous schemes.

  15. Flight calibration tests of a nose-boom-mounted fixed hemispherical flow-direction sensor

    NASA Technical Reports Server (NTRS)

    Armistead, K. H.; Webb, L. D.

    1973-01-01

    Flight calibrations of a fixed hemispherical flow angle-of-attack and angle-of-sideslip sensor were made from Mach numbers of 0.5 to 1.8. Maneuvers were performed by an F-104 airplane at selected altitudes to compare the measurement of flow angle of attack from the fixed hemispherical sensor with that from a standard angle-of-attack vane. The hemispherical flow-direction sensor measured differential pressure at two angle-of-attack ports and two angle-of-sideslip ports in diametrically opposed positions. Stagnation pressure was measured at a center port. The results of these tests showed that the calibration curves for the hemispherical flow-direction sensor were linear for angles of attack up to 13 deg. The overall uncertainty in determining angle of attack from these curves was plus or minus 0.35 deg or less. A Mach number position error calibration curve was also obtained for the hemispherical flow-direction sensor. The hemispherical flow-direction sensor exhibited a much larger position error than a standard uncompensated pitot-static probe.

  16. RApid Primary care Initiation of Drug treatment for Transient Ischaemic Attack (RAPID−TIA): study protocol for a pilot randomised controlled trial

    PubMed Central

    2013-01-01

    Background People who have a transient ischaemic attack (TIA) or minor stroke are at high risk of a recurrent stroke, particularly in the first week after the event. Early initiation of secondary prevention drugs is associated with an 80% reduction in risk of stroke recurrence. This raises the question as to whether these drugs should be given before being seen by a specialist – that is, in primary care or in the emergency department. The aims of the RAPID-TIA pilot trial are to determine the feasibility of a randomised controlled trial, to analyse cost effectiveness and to ask: Should general practitioners and emergency doctors (primary care physicians) initiate secondary preventative measures in addition to aspirin in people they see with suspected TIA or minor stroke at the time of referral to a specialist? Methods/Design This is a pilot randomised controlled trial with a sub-study of accuracy of primary care physician diagnosis of TIA. In the pilot trial, we aim to recruit 100 patients from 30 general practices (including out-of-hours general practice centres) and 1 emergency department whom the primary care physician diagnoses with TIA or minor stroke and randomly assign them to usual care (that is, initiation of aspirin and referral to a TIA clinic) or usual care plus additional early initiation of secondary prevention drugs (a blood-pressure lowering protocol, simvastatin 40 mg and dipyridamole 200 mg m/r bd). The primary outcome of the main study will be the number of strokes at 90 days. The diagnostic accuracy sub-study will include these 100 patients and an additional 70 patients in whom the primary care physician thinks the diagnosis of TIA is possible, rather than probable. For the pilot trial, we will report recruitment rate, follow-up rate, a preliminary estimate of the primary event rate and occurrence of any adverse events. For the diagnostic study, we will calculate sensitivity and specificity of primary care physician diagnosis using the final TIA clinic diagnosis as the reference standard. Discussion This pilot study will be used to estimate key parameters that are needed to design the main study and to estimate the accuracy of primary care diagnosis of TIA. The planned follow-on trial will have important implications for the initial management of people with suspected TIA. Trial registration ISRCTN62019087 PMID:23819476

  17. Plasmodium falciparum incidence relative to entomologic inoculation rates at a site proposed for testing malaria vaccines in western Kenya.

    PubMed

    Beier, J C; Oster, C N; Onyango, F K; Bales, J D; Sherwood, J A; Perkins, P V; Chumo, D K; Koech, D V; Whitmire, R E; Roberts, C R

    1994-05-01

    Relationships between Plasmodium falciparum incidence and entomologic inoculation rates (EIRs) were determined for a 21-month period in Saradidi, western Kenya, in preparation for malaria vaccine field trials. Children, ranging in age from six months to six years and treated to clear malaria parasites, were monitored daily for up to 12 weeks to detect new malaria infections. Overall, new P. falciparum infections were detected in 77% of 809 children. The percentage of children that developed infections per two-week period averaged 34.7%, ranging from 7.3% to 90.9%. Transmission by vector populations was detected in 86.4% (38 of 44) of the two-week periods, with daily EIRs averaging 0.75 infective bites per person. Periods of intense transmission during April to August, and from November to January, coincided with seasonal rains. Relationships between daily malaria attack rates and EIRs indicated that an average of only 7.5% (1 in 13) of the sporozoite inoculations produced new infections in children. Regression analysis demonstrated that EIRs accounted for 74% of the variation in attack rates. One of the components of the EIR, the human-biting rate, alone accounted for 68% of the variation in attack rates. Thus, measurements of either the EIR or the human-biting rate can be used to predict corresponding attack rates in children. These baseline epidemiologic studies indicate that the intense transmission patterns of P. falciparum in Saradidi will provide excellent conditions for evaluating malaria vaccine efficacy.

  18. SUNCT and SUNA: Recognition and Treatment.

    PubMed

    Pareja, Juan A; Alvarez, Mónica; Montojo, Teresa

    2013-02-01

    The problem of short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) and short-lasting unilateral neuralgiform headache attacks with cranial autonomic symptoms (SUNA) management remains unsolved. Despite a myriad of therapeutic trials, no convincingly effective remedy for SUNCT and SUNA is available at present. Based on open-label communications, some patients seemed to benefit from some pharmacologic, interventional, or invasive procedures. Possible effective preventive drugs are carbamazepine, lamotrigine, gabapentin, and topiramate. At present, the drug of choice for SUNCT seems to be lamotrigine whereas SUNA may better respond to gabapentin. There is no available abortive treatment for the individual attacks. During the worst periods, intravenous lidocaine may decrease the flow of SUNCT/SUNA attacks. In SUNCT, bilateral blockade of the greater occipital nerve, and superior cervical ganglion opioid blockade have been reported as temporary/partially effective in one patient each. Botulinum toxin injected around the symptomatic orbit provided sustained relief to one patient. Owing to the scarcity of reports the results of these interventions should be taken as preliminary. Invasive therapy with interventions directed to the first division of the trigeminal nerve or Gasserian ganglion, with local anesthetics or alcohol, radiofrequency thermocoagulation, microvascular decompression, and gamma-knife neurosurgery, have been tried in the treatment of refractory SUNCT. Some patients seemed to benefit from such interventions, but one should still have a critical attitude to these claims since no convincing results have been obtained as yet. The few SUNCT patients who underwent deep brain hypothalamic stimulation obtained a substantial and persistent relief.

  19. STROKE OUTCOMES AMONG PARTICIPANTS RANDOMIZED TO CHLORTHALIDONE, AMLODIPINE OR LISINOPRIL IN ALLHAT

    PubMed Central

    Yamal, José-Miguel; Oparil, Suzanne; Davis, Barry R.; Alderman, Michael H.; Calhoun, David A.; Cushman, William C.; Fendley, Herbert F.; Franklin, Stanley S.; Habib, Gabriel B.; Pressel, Sara L.; Probstfield, Jeffrey L.; Sastrasinh, Sithiporn

    2014-01-01

    Background The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) was a randomized, double-blind, practice-based, active-control, comparative effectiveness trial in 33,357 high-risk hypertensive participants. Methods and Results ALLHAT compared cardiovascular disease outcomes in participants initially treated with angiotensin-converting enzyme inhibitor (lisinopril), calcium channel blocker (amlodipine), or thiazide-type diuretic (chlorthalidone). We report stroke outcomes in 1517 participants in-trial and 1596 additional participants during post-trial passive surveillance, for total follow-up of 8–13 years. Stroke rates were higher with lisinopril (6-year rate/100=6.4) than with chlorthalidone (5.8) or amlodipine (5.5) in-trial but not including post-trial (10-year rates/100=13.2 [chlorthalidone], 13.1[amlodipine], and 13.7 [lisinopril]). In- trial differences were driven by race (race-by-lisinopril/chlorthalidone interaction P=0.005, race-by-amlodipine/lisinopril interaction P=0.012) and gender (gender-by-lisinopril/amlodipine interaction P=0.041), separately. No treatment differences overall, or by race or gender, were detected over the 10-year period. No differences appeared among treatment groups in adjusted risk of all-cause mortality including post-trial for participants with nonfatal in-trial strokes. Conclusions Among Blacks and women, lisinopril was less effective in preventing stroke in-trial than either chlorthalidone or amlodipine, even after adjusting for differences in systolic blood pressure. These differences abated by the end of the post-trial period. PMID:25455006

  20. Adaptive cyber-attack modeling system

    NASA Astrophysics Data System (ADS)

    Gonsalves, Paul G.; Dougherty, Edward T.

    2006-05-01

    The pervasiveness of software and networked information systems is evident across a broad spectrum of business and government sectors. Such reliance provides an ample opportunity not only for the nefarious exploits of lone wolf computer hackers, but for more systematic software attacks from organized entities. Much effort and focus has been placed on preventing and ameliorating network and OS attacks, a concomitant emphasis is required to address protection of mission critical software. Typical software protection technique and methodology evaluation and verification and validation (V&V) involves the use of a team of subject matter experts (SMEs) to mimic potential attackers or hackers. This manpower intensive, time-consuming, and potentially cost-prohibitive approach is not amenable to performing the necessary multiple non-subjective analyses required to support quantifying software protection levels. To facilitate the evaluation and V&V of software protection solutions, we have designed and developed a prototype adaptive cyber attack modeling system. Our approach integrates an off-line mechanism for rapid construction of Bayesian belief network (BN) attack models with an on-line model instantiation, adaptation and knowledge acquisition scheme. Off-line model construction is supported via a knowledge elicitation approach for identifying key domain requirements and a process for translating these requirements into a library of BN-based cyber-attack models. On-line attack modeling and knowledge acquisition is supported via BN evidence propagation and model parameter learning.

  1. Practical quantum private query with better performance in resisting joint-measurement attack

    NASA Astrophysics Data System (ADS)

    Wei, Chun-Yan; Wang, Tian-Yin; Gao, Fei

    2016-04-01

    As a kind of practical protocol, quantum-key-distribution (QKD)-based quantum private queries (QPQs) have drawn lots of attention. However, joint-measurement (JM) attack poses a noticeable threat to the database security in such protocols. That is, by JM attack a malicious user can illegally elicit many more items from the database than the average amount an honest one can obtain. Taking Jacobi et al.'s protocol as an example, by JM attack a malicious user can obtain as many as 500 bits, instead of the expected 2.44 bits, from a 104-bit database in one query. It is a noticeable security flaw in theory, and would also arise in application with the development of quantum memories. To solve this problem, we propose a QPQ protocol based on a two-way QKD scheme, which behaves much better in resisting JM attack. Concretely, the user Alice cannot get more database items by conducting JM attack on the qubits because she has to send them back to Bob (the database holder) before knowing which of them should be jointly measured. Furthermore, JM attack by both Alice and Bob would be detected with certain probability, which is quite different from previous protocols. Moreover, our protocol retains the good characters of QKD-based QPQs, e.g., it is loss tolerant and robust against quantum memory attack.

  2. Serotonin Augmentation Reduces Response to Attack in Aggressive Individuals

    PubMed Central

    Berman, Mitchell E.; McCloskey, Michael S.; Fanning, Jennifer R.; Schumacher, Julie A.; Coccaro, Emil F.

    2009-01-01

    We tested the theory that central serotonin (5- hydroxytryptamine, or 5-HT) activity regulates aggression by modulating response to provocation. Eighty men and women (40 with and 40 without a history of aggression) were randomly assigned to receive either 40 mg of paroxetine (to acutely augment serotonergic activity) or a placebo, administered using double-blind procedures. Aggression was assessed during a competitive reaction time game with a fictitious opponent. Shocks were selected by the participant and opponent before each trial, with the loser on each trial receiving the shock set by the other player. Provocation was manipulated by having the opponent select increasingly intense shocks for the participant and eventually an ostensibly severe shock toward the end of the trials. Aggression was measured by the number of severe shocks set by the participant for the opponent. As predicted, aggressive responding after provocation was attenuated by augmentation of serotonin in individuals with a pronounced history of aggression. PMID:19422623

  3. Prospective testing of ICHD-3 beta diagnostic criteria for migraine with aura and migraine with typical aura in patients with transient ischemic attacks.

    PubMed

    Lebedeva, Elena R; Gurary, Natalia M; Gilev, Denis V; Olesen, Jes

    2018-03-01

    Introduction The International Classification of Headache Disorders 3rd edition beta (ICHD-3 beta) gave alternative diagnostic criteria for 1.2 migraine with aura (MA) and 1.2.1 migraine with typical aura (MTA) in the appendix. The latter were presumed to better differentiate transient ischemic attacks (TIA) from MA. The aim of the present study was to field test that. Methods Soon after admission, a neurologist interviewed 120 consecutive patients diagnosed with TIA after MRI or CT. Semi-structured interview forms addressed all details of the TIA episode and all information necessary to apply the ICHD-3beta diagnostic criteria for 1.2, 1.2.1, A1.2 and A1.2.1. Results Requiring at least one identical previous attack, the main body and the appendix criteria performed almost equally well. But requiring only one attack, more than a quarter of TIA patients also fulfilled the main body criteria for 1.2. Specificity was as follows for one attack: 1.2: 0.73, A1.2: 0.91, 1.2.1: 0.88 and A1.2.1: 1.0. Sensitivity when tested against ICHD-2 criteria were 100% for the main body criteria (because they were unchanged), 96% for A1.2 and 94% for A1.2.1. Conclusion The appendix criteria performed much better than the main body criteria for 1.2 MA and 1.2.1 MTA when diagnosing one attack (probable MA). We recommend that the appendix criteria should replace the main body criteria in the ICHD-3.

  4. Effects of Motivation: Rewarding Hackers for Undetected Attacks Cause Analysts to Perform Poorly.

    PubMed

    Maqbool, Zahid; Makhijani, Nidhi; Pammi, V S Chandrasekhar; Dutt, Varun

    2017-05-01

    The aim of this study was to determine how monetary motivations influence decision making of humans performing as security analysts and hackers in a cybersecurity game. Cyberattacks are increasing at an alarming rate. As cyberattacks often cause damage to existing cyber infrastructures, it is important to understand how monetary rewards may influence decision making of hackers and analysts in the cyber world. Currently, only limited attention has been given to this area. In an experiment, participants were randomly assigned to three between-subjects conditions ( n = 26 for each condition): equal payoff, where the magnitude of monetary rewards for hackers and defenders was the same; rewarding hacker, where the magnitude of monetary reward for hacker's successful attack was 10 times the reward for analyst's successful defense; and rewarding analyst, where the magnitude of monetary reward for analyst's successful defense was 10 times the reward for hacker's successful attack. In all conditions, half of the participants were human hackers playing against Nash analysts and half were human analysts playing against Nash hackers. Results revealed that monetary rewards for human hackers and analysts caused a decrease in attack and defend actions compared with the baseline. Furthermore, rewarding human hackers for undetected attacks made analysts deviate significantly from their optimal behavior. If hackers are rewarded for their undetected attack actions, then this causes analysts to deviate from optimal defend proportions. Thus, analysts need to be trained not become overenthusiastic in defending networks. Applications of our results are to networks where the influence of monetary rewards may cause information theft and system damage.

  5. Protection via parasitism: Datura odors attract parasitoid flies, which inhibit Manduca larvae from feeding and growing but may not help plants.

    PubMed

    Wilson, J K; Woods, H A

    2015-12-01

    Insect carnivores frequently use olfactory cues from plants to find prey or hosts. For plants, the benefits of attracting parasitoids have been controversial, partly because parasitoids often do not kill their host insect immediately. Furthermore, most research has focused on the effects of solitary parasitoids on growth and feeding of hosts, even though many parasitoids are gregarious (multiple siblings inhabit the same host). Here, we examine how a gregarious parasitoid, the tachinid fly Drino rhoeo, uses olfactory cues from the host plant Datura wrightii to find the sphingid herbivore Manduca sexta, and how parasitism affects growth and feeding of host larvae. In behavioral trials using a Y-olfactometer, female flies were attracted to olfactory cues emitted by attacked plants and by cues emitted from the frass produced by larval Manduca sexta. M. sexta caterpillars that were parasitized by D. rhoeo grew to lower maximum weights, grew more slowly, and ate less of their host plant. We also present an analytical model to predict how tri-trophic interactions change with varying herbivory levels, parasitization rates and plant sizes. This model predicted that smaller plants gain a relatively greater benefit compared to large plants in attracting D. rhoeo. By assessing the behavior, the effects of host performance, and the variation in ecological parameters of the system, we can better understand the complex interactions between herbivorous insects, the plants they live on and the third trophic level members that attack them.

  6. Different systolic blood pressure targets for people with history of stroke or transient ischaemic attack: PAST-BP (Prevention After Stroke—Blood Pressure) randomised controlled trial

    PubMed Central

    McManus, Richard J; Roalfe, Andrea; Fletcher, Kate; Taylor, Clare J; Martin, Una; Virdee, Satnam; Greenfield, Sheila; Hobbs, F D Richard

    2016-01-01

    Objective To assess whether using intensive blood pressure targets leads to lower blood pressure in a community population of people with prevalent cerebrovascular disease. Design Open label randomised controlled trial. Setting 99 general practices in England, with participants recruited in 2009-11. Participants People with a history of stroke or transient ischaemic attack whose systolic blood pressure was 125 mm Hg or above. Interventions Intensive systolic blood pressure target (<130 mm Hg or 10 mm Hg reduction from baseline if this was <140 mm Hg) or standard target (<140 mm Hg). Apart from the different target, patients in both arms were actively managed in the same way with regular reviews by the primary care team. Main outcome measure Change in systolic blood pressure between baseline and 12 months. Results 529 patients (mean age 72) were enrolled, 266 to the intensive target arm and 263 to the standard target arm, of whom 379 were included in the primary analysis (182 (68%) intensive arm; 197 (75%) standard arm). 84 patients withdrew from the study during the follow-up period (52 intensive arm; 32 standard arm). Mean systolic blood pressure dropped by 16.1 mm Hg to 127.4 mm Hg in the intensive target arm and by 12.8 mm Hg to 129.4 mm Hg in the standard arm (difference between groups 2.9 (95% confidence interval 0.2 to 5.7) mm Hg; P=0.03). Conclusions Aiming for target below 130 mm Hg rather than 140 mm Hg for systolic blood pressure in people with cerebrovascular disease in primary care led to a small additional reduction in blood pressure. Active management of systolic blood pressure in this population using a <140 mm Hg target led to a clinically important reduction in blood pressure. Trial registration Current Controlled Trials ISRCTN29062286. PMID:26919870

  7. A randomised controlled trial of aerobic exercise after transient ischaemic attack or minor stroke to prevent cognitive decline: the MoveIT study protocol.

    PubMed

    Boss, H M; Van Schaik, S M; Deijle, I A; de Melker, E C; van den Berg, B T J; Scherder, E J A; Bosboom, W M J; Weinstein, H C; Van den Berg-Vos, R M

    2014-12-31

    Patients with transient ischaemic attack (TIA) or stroke are at risk for cognitive impairment and dementia. Currently, there is no known effective strategy to prevent this cognitive decline. Increasing evidence exists that physical exercise is beneficial for cognitive function. However, in patients with TIA or stroke who are at risk of cognitive impairment and dementia, only a few trials have been conducted. In this study, we aim to investigate whether a physical exercise programme (MoveIT) can prevent cognitive decline in patients in the acute phase after a TIA or minor ischaemic stroke. A single-blinded randomised controlled trial will be conducted to investigate the effect of an aerobic exercise programme on cognition compared with usual care. 120 adult patients with a TIA or minor ischaemic stroke less than 1 month ago will be randomly allocated to an exercise programme consisting of a 12-week aerobic exercise programme and regular follow-up visits to a specialised physiotherapist during the period of 1 year or to usual care. Outcome measures will be assessed at the baseline, and at the 1-year and 2-year follow-up. The primary outcome is cognitive functioning measured with the Montreal Cognitive Assessment (MoCA) test and with additional neuropsychological tests. Secondary outcomes include maximal exercise capacity, self-reported physical activity and measures of secondary prevention. The study received ethical approval from the VU University Amsterdam Ethics committee (2011/383). The results of this study will be published in peer-reviewed journals and presented at international conferences. We will also disseminate the main results to our participants in a letter. The Nederlands Trial Register NTR3884. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  8. Study of aerodynamic technology for VSTOL fighter/attack aircraft, phase 1

    NASA Technical Reports Server (NTRS)

    Driggers, H. H.

    1978-01-01

    A conceptual design study was performed of a vertical attitude takeoff and landing (VATOL) fighter/attack aircraft. The configuration has a close-coupled canard-delta wing, side two-dimensional ramp inlets, and two augmented turbofan engines with thrust vectoring capability. Performance and sensitivities to objective requirements were calculated. Aerodynamic characteristics were estimated based on contractor and NASA wind tunnel data. Computer simulations of VATOL transitions were performed. Successful transitions can be made, even with series post-stall instabilities, if reaction controls are properly phased. Principal aerodynamic uncertainties identified were post-stall aerodynamics, transonic aerodynamics with thrust vectoring and inlet performance in VATOL transition. A wind tunnel research program was recommended to resolve the aerodynamic uncertainties.

  9. What's Next in Complex Networks? Capturing the Concept of Attacking Play in Invasive Team Sports.

    PubMed

    Ramos, João; Lopes, Rui J; Araújo, Duarte

    2018-01-01

    The evolution of performance analysis within sports sciences is tied to technology development and practitioner demands. However, how individual and collective patterns self-organize and interact in invasive team sports remains elusive. Social network analysis has been recently proposed to resolve some aspects of this problem, and has proven successful in capturing collective features resulting from the interactions between team members as well as a powerful communication tool. Despite these advances, some fundamental team sports concepts such as an attacking play have not been properly captured by the more common applications of social network analysis to team sports performance. In this article, we propose a novel approach to team sports performance centered on sport concepts, namely that of an attacking play. Network theory and tools including temporal and bipartite or multilayered networks were used to capture this concept. We put forward eight questions directly related to team performance to discuss how common pitfalls in the use of network tools for capturing sports concepts can be avoided. Some answers are advanced in an attempt to be more precise in the description of team dynamics and to uncover other metrics directly applied to sport concepts, such as the structure and dynamics of attacking plays. Finally, we propose that, at this stage of knowledge, it may be advantageous to build up from fundamental sport concepts toward complex network theory and tools, and not the other way around.

  10. FSM-F: Finite State Machine Based Framework for Denial of Service and Intrusion Detection in MANET.

    PubMed

    N Ahmed, Malik; Abdullah, Abdul Hanan; Kaiwartya, Omprakash

    2016-01-01

    Due to the continuous advancements in wireless communication in terms of quality of communication and affordability of the technology, the application area of Mobile Adhoc Networks (MANETs) significantly growing particularly in military and disaster management. Considering the sensitivity of the application areas, security in terms of detection of Denial of Service (DoS) and intrusion has become prime concern in research and development in the area. The security systems suggested in the past has state recognition problem where the system is not able to accurately identify the actual state of the network nodes due to the absence of clear definition of states of the nodes. In this context, this paper proposes a framework based on Finite State Machine (FSM) for denial of service and intrusion detection in MANETs. In particular, an Interruption Detection system for Adhoc On-demand Distance Vector (ID-AODV) protocol is presented based on finite state machine. The packet dropping and sequence number attacks are closely investigated and detection systems for both types of attacks are designed. The major functional modules of ID-AODV includes network monitoring system, finite state machine and attack detection model. Simulations are carried out in network simulator NS-2 to evaluate the performance of the proposed framework. A comparative evaluation of the performance is also performed with the state-of-the-art techniques: RIDAN and AODV. The performance evaluations attest the benefits of proposed framework in terms of providing better security for denial of service and intrusion detection attacks.

  11. Binary Hypothesis Testing With Byzantine Sensors: Fundamental Tradeoff Between Security and Efficiency

    NASA Astrophysics Data System (ADS)

    Ren, Xiaoqiang; Yan, Jiaqi; Mo, Yilin

    2018-03-01

    This paper studies binary hypothesis testing based on measurements from a set of sensors, a subset of which can be compromised by an attacker. The measurements from a compromised sensor can be manipulated arbitrarily by the adversary. The asymptotic exponential rate, with which the probability of error goes to zero, is adopted to indicate the detection performance of a detector. In practice, we expect the attack on sensors to be sporadic, and therefore the system may operate with all the sensors being benign for extended period of time. This motivates us to consider the trade-off between the detection performance of a detector, i.e., the probability of error, when the attacker is absent (defined as efficiency) and the worst-case detection performance when the attacker is present (defined as security). We first provide the fundamental limits of this trade-off, and then propose a detection strategy that achieves these limits. We then consider a special case, where there is no trade-off between security and efficiency. In other words, our detection strategy can achieve the maximal efficiency and the maximal security simultaneously. Two extensions of the secure hypothesis testing problem are also studied and fundamental limits and achievability results are provided: 1) a subset of sensors, namely "secure" sensors, are assumed to be equipped with better security countermeasures and hence are guaranteed to be benign, 2) detection performance with unknown number of compromised sensors. Numerical examples are given to illustrate the main results.

  12. MBCP - Approach - Immunotherapy | Center for Cancer Research

    Cancer.gov

    Immunotherapy CCR investigators pioneered the use of the tuberculosis vaccine—Bacillus Calmette-Guerin (BCG)—in the treatment of bladder cancer. In cases where the tumor burden is not too high and direct contact can be made with the urothelium surface of the bladder, BCG application appears to elicit an immune response that attacks the tumor as well as the attenuated virus. Ongoing clinical trials focusing on enhancing the patient’s immune system are listed below.

  13. Kombucha--toxicity alert.

    PubMed

    The Kombucha mushroom, also known as Manchurian mushroom, is a mail-order product touted to lower blood pressure and raise T-cell counts. No controlled trials have been conducted to test these claims. Aspergillus, a mold that may grow on the Kombucha mushroom, attacks the brain and may be fatal to persons with weakened immune systems. Reported toxicity reactions have included stomach problems and yeast infections. Taking Kombucha in combination with other drugs may affect the drugs potency.

  14. Acupuncture for the prevention of episodic migraine.

    PubMed

    Linde, Klaus; Allais, Gianni; Brinkhaus, Benno; Fei, Yutong; Mehring, Michael; Vertosick, Emily A; Vickers, Andrew; White, Adrian R

    2016-06-28

    Acupuncture is often used for migraine prevention but its effectiveness is still controversial. We present an update of our Cochrane review from 2009. To investigate whether acupuncture is a) more effective than no prophylactic treatment/routine care only; b) more effective than sham (placebo) acupuncture; and c) as effective as prophylactic treatment with drugs in reducing headache frequency in adults with episodic migraine. We searched the Cochrane Central Register of Controlled Trials (CENTRAL: 2016, issue 1); MEDLINE (via Ovid, 2008 to January 2016); Ovid EMBASE (2008 to January 2016); and Ovid AMED (1985 to January 2016). We checked PubMed for recent publications to April 2016. We searched the World Health Organization (WHO) Clinical Trials Registry Platform to February 2016 for ongoing and unpublished trials. We included randomized trials at least eight weeks in duration that compared an acupuncture intervention with a no-acupuncture control (no prophylactic treatment or routine care only), a sham-acupuncture intervention, or prophylactic drug in participants with episodic migraine. Two reviewers checked eligibility; extracted information on participants, interventions, methods and results, and assessed risk of bias and quality of the acupuncture intervention. The primary outcome was migraine frequency (preferably migraine days, attacks or headache days if migraine days not measured/reported) after treatment and at follow-up. The secondary outcome was response (at least 50% frequency reduction). Safety outcomes were number of participants dropping out due to adverse effects and number of participants reporting at least one adverse effect. We calculated pooled effect size estimates using a fixed-effect model. We assessed the evidence using GRADE and created 'Summary of findings' tables. Twenty-two trials including 4985 participants in total (median 71, range 30 to 1715) met our updated selection criteria. We excluded five previously included trials from this update because they included people who had had migraine for less than 12 months, and included five new trials. Five trials had a no-acupuncture control group (either treatment of attacks only or non-regulated routine care), 15 a sham-acupuncture control group, and five a comparator group receiving prophylactic drug treatment. In comparisons with no-acupuncture control groups and groups receiving prophylactic drug treatment, there was risk of performance and detection bias as blinding was not possible. Overall the quality of the evidence was moderate. Comparison with no acupunctureAcupuncture was associated with a moderate reduction of headache frequency over no acupuncture after treatment (four trials, 2199 participants; standardised mean difference (SMD) -0.56; 95% CI -0.65 to -0.48); findings were statistically heterogeneous (I² = 57%; moderate quality evidence). After treatment headache frequency at least halved in 41% of participants receiving acupuncture and 17% receiving no acupuncture (pooled risk ratio (RR) 2.40; 95% CI 2.08 to 2.76; 4 studies, 2519 participants) with a corresponding number needed to treat for an additional beneficial outcome (NNTB) of 4 (95% CI 3 to 6); there was no indication of statistical heterogeneity (I² = 7%; moderate quality evidence). The only trial with post-treatment follow-up found a small but significant benefit 12 months after randomisation (RR 2.16; 95% CI 1.35 to 3.45; NNT 7; 95% 4 to 25; 377 participants, low quality evidence). Comparison with sham acupunctureBoth after treatment (12 trials, 1646 participants) and at follow-up (10 trials, 1534 participants), acupuncture was associated with a small but statistically significant frequency reduction over sham (moderate quality evidence). The SMD was -0.18 (95% CI -0.28 to -0.08; I² = 47%) after treatment and -0.19 (95% CI -0.30 to -0.09; I² = 59%) at follow-up. After treatment headache frequency at least halved in 50% of participants receiving true acupuncture and 41% receiving sham acupuncture (pooled RR 1.23, 95% CI 1.11 to 1.36; I² = 48%; 14 trials, 1825 participants) and at follow-up in 53% and 42%, respectively (pooled RR 1.25, 95% CI 1.13 to 1.39; I² = 61%; 11 trials, 1683 participants; moderate quality evidence). The corresponding NNTBs are 11 (95% CI 7.00 to 20.00) and 10 (95% CI 6.00 to 18.00), respectively. The number of participants dropping out due to adverse effects (odds ratio (OR) 2.84; 95% CI 0.43 to 18.71; 7 trials, 931 participants; low quality evidence) and the number of participants reporting adverse effects (OR 1.15; 95% CI 0.85 to 1.56; 4 trials, 1414 participants; moderate quality evidence) did not differ significantly between acupuncture and sham groups. Comparison with prophylactic drug treatmentAcupuncture reduced migraine frequency significantly more than drug prophylaxis after treatment ( SMD -0.25; 95% CI -0.39 to -0.10; 3 trials, 739 participants), but the significance was not maintained at follow-up (SMD -0.13; 95% CI -0.28 to 0.01; 3 trials, 744 participants; moderate quality evidence). After three months headache frequency at least halved in 57% of participants receiving acupuncture and 46% receiving prophylactic drugs (pooled RR 1.24; 95% CI 1.08 to 1.44) and after six months in 59% and 54%, respectively (pooled RR 1.11; 95% CI 0.97 to 1.26; moderate quality evidence). Findings were consistent among trials with I² being 0% in all analyses. Trial participants receiving acupuncture were less likely to drop out due to adverse effects (OR 0.27; 95% CI 0.08 to 0.86; 4 trials, 451 participants) and to report adverse effects (OR 0.25; 95% CI 0.10 to 0.62; 5 trials 931 participants) than participants receiving prophylactic drugs (moderate quality evidence). The available evidence suggests that adding acupuncture to symptomatic treatment of attacks reduces the frequency of headaches. Contrary to the previous findings, the updated evidence also suggests that there is an effect over sham, but this effect is small. The available trials also suggest that acupuncture may be at least similarly effective as treatment with prophylactic drugs. Acupuncture can be considered a treatment option for patients willing to undergo this treatment. As for other migraine treatments, long-term studies, more than one year in duration, are lacking.

  15. What happens in the pith stays in the pith: tissue-localized defense responses facilitate chemical niche differentiation between two spatially separated herbivores.

    PubMed

    Lee, Gisuk; Joo, Youngsung; Kim, Sang-Gyu; Baldwin, Ian T

    2017-11-01

    Herbivore attack is known to elicit systemic defense responses that spread throughout the host plant and influence the performance of other herbivores. While these plant-mediated indirect competitive interactions are well described, and the co-existence of herbivores from different feeding guilds is common, the mechanisms of co-existence are poorly understood. In both field and glasshouse experiments with a native tobacco, Nicotiana attenuata, we found no evidence of negative interactions when plants were simultaneously attacked by two spatially separated herbivores: a leaf chewer Manduca sexta and a stem borer Trichobaris mucorea. T. mucorea attack elicited jasmonic acid (JA) and jasmonoyl-l-isoleucine bursts in the pith of attacked stems similar to those that occur in leaves when M. sexta attacks N. attenuata leaves. Pith chlorogenic acid (CGA) levels increased 1000-fold to levels 6-fold higher than leaf levels after T. mucorea attack; these increases in pith CGA levels, which did not occur in M. sexta-attacked leaves, required JA signaling. With plants silenced in CGA biosynthesis (irHQT plants), CGA, as well as other caffeic acid conjugates, was demonstrated in both glasshouse and field experiments to function as a direct defense protecting piths against T. mucorea attack, but not against leaf chewers or sucking insects. T. mucorea attack does not systemically activate JA signaling in leaves, while M. sexta leaf-attack transiently induces detectable but minor pith JA levels that are dwarfed by local responses. We conclude that tissue-localized defense responses allow tissue-specialized herbivores to share the same host and occupy different chemical defense niches in the same hostplant. © 2017 The Authors The Plant Journal © 2017 John Wiley & Sons Ltd.

  16. Classification of HTTP Attacks: A Study on the ECML/PKDD 2007 Discovery Challenge

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gallagher, Brian; Eliassi-Rad, Tina

    2009-07-08

    As the world becomes more reliant on Web applications for commercial, financial, and medical transactions, cyber attacks on the World Wide Web are increasing in frequency and severity. Web applications provide an attractive alternative to traditional desktop applications due to their accessibility and ease of deployment. However, the accessibility of Web applications also makes them extremely vulnerable to attack. This inherent vulnerability is intensified by the distributed nature ofWeb applications and the complexity of configuring application servers. These factors have led to a proliferation of Web-based attacks, in which attackers surreptitiously inject code into HTTP requests, allowing them to executemore » arbitrary commands on remote systems and perform malicious activities such as reading, altering, or destroying sensitive data. One approach for dealing with HTTP-based attacks is to identify malicious code in incoming HTTP requests and eliminate bad requests before they are processed. Using machine learning techniques, we can build a classifier to automatically label requests as “Valid” or “Attack.” For this study, we develop a simple, but effective HTTP attack classifier, based on the vector space model used commonly for Information Retrieval. Our classifier not only separates attacks from valid requests, but can also identify specific attack types (e.g., “SQL Injection” or “Path Traversal”). We demonstrate the effectiveness of our approach through experiments on the ECML/PKDD 2007 Discovery Challenge data set. Specifically, we show that our approach achieves higher precision and recall than previous methods. In addition, our approach has a number of desirable characteristics, including robustness to missing contextual information, interpretability of models, and scalability.« less

  17. Analyzing Cyber-Physical Threats on Robotic Platforms.

    PubMed

    Ahmad Yousef, Khalil M; AlMajali, Anas; Ghalyon, Salah Abu; Dweik, Waleed; Mohd, Bassam J

    2018-05-21

    Robots are increasingly involved in our daily lives. Fundamental to robots are the communication link (or stream) and the applications that connect the robots to their clients or users. Such communication link and applications are usually supported through client/server network connection. This networking system is amenable of being attacked and vulnerable to the security threats. Ensuring security and privacy for robotic platforms is thus critical, as failures and attacks could have devastating consequences. In this paper, we examine several cyber-physical security threats that are unique to the robotic platforms; specifically the communication link and the applications. Threats target integrity, availability and confidential security requirements of the robotic platforms, which use MobileEyes/arnlServer client/server applications. A robot attack tool (RAT) was developed to perform specific security attacks. An impact-oriented approach was adopted to analyze the assessment results of the attacks. Tests and experiments of attacks were conducted in simulation environment and physically on the robot. The simulation environment was based on MobileSim; a software tool for simulating, debugging and experimenting on MobileRobots/ActivMedia platforms and their environments. The robot platform PeopleBot TM was used for physical experiments. The analysis and testing results show that certain attacks were successful at breaching the robot security. Integrity attacks modified commands and manipulated the robot behavior. Availability attacks were able to cause Denial-of-Service (DoS) and the robot was not responsive to MobileEyes commands. Integrity and availability attacks caused sensitive information on the robot to be hijacked. To mitigate security threats, we provide possible mitigation techniques and suggestions to raise awareness of threats on the robotic platforms, especially when the robots are involved in critical missions or applications.

  18. Panic attacks and panic disorder in a population-based sample of active Canadian military personnel.

    PubMed

    Kinley, D Jolene; Walker, John R; Mackenzie, Corey S; Sareen, Jitender

    2011-01-01

    The factors contributing to psychiatric problems among military personnel, particularly for panic, are unclear. The objective of this study was to examine the prevalence and correlates of panic disorder and panic attacks in the Canadian military. Statistics Canada and the Department of National Defense conducted the Canadian Community Health Survey-Canadian Forces Supplement in 2002 (May to December) with a representative sample of active Canadian military personnel (aged 16-54 years; N = 8,441; response rate, 81.5%). Comparisons were made between respondents with no past-year panic attacks, panic attacks without panic disorder, and panic disorder on measures of DSM-IV mental disorders, as well as validated measures of disability, distress, suicidal ideation, perceived need for mental health treatment, and mental health service use. Lifetime exposure to combat operations, witnessing of atrocities, and deployments were also assessed. Panic disorder and panic attacks were common in the military population, with past-year prevalence estimates of 1.8% and 7.0%, respectively. Both panic disorder and panic attacks were associated with increased odds of all mental disorders assessed, suicidal ideation, 2-week disability, and distress. Perceived need for mental health treatment and service use were common in individuals with panic attacks and panic disorder (perceived need: 46.3% for panic attacks, 89.6% for panic disorder; service use: 32.5% for panic attacks, 74.5% for panic disorder). Panic attacks and panic disorder in the military are associated with outcomes that could be detrimental to well-being and work performance, and early detection of panic in this population could help reduce these negative outcomes. © Copyright 2011 Physicians Postgraduate Press, Inc.

  19. Analyzing Cyber-Physical Threats on Robotic Platforms †

    PubMed Central

    2018-01-01

    Robots are increasingly involved in our daily lives. Fundamental to robots are the communication link (or stream) and the applications that connect the robots to their clients or users. Such communication link and applications are usually supported through client/server network connection. This networking system is amenable of being attacked and vulnerable to the security threats. Ensuring security and privacy for robotic platforms is thus critical, as failures and attacks could have devastating consequences. In this paper, we examine several cyber-physical security threats that are unique to the robotic platforms; specifically the communication link and the applications. Threats target integrity, availability and confidential security requirements of the robotic platforms, which use MobileEyes/arnlServer client/server applications. A robot attack tool (RAT) was developed to perform specific security attacks. An impact-oriented approach was adopted to analyze the assessment results of the attacks. Tests and experiments of attacks were conducted in simulation environment and physically on the robot. The simulation environment was based on MobileSim; a software tool for simulating, debugging and experimenting on MobileRobots/ActivMedia platforms and their environments. The robot platform PeopleBotTM was used for physical experiments. The analysis and testing results show that certain attacks were successful at breaching the robot security. Integrity attacks modified commands and manipulated the robot behavior. Availability attacks were able to cause Denial-of-Service (DoS) and the robot was not responsive to MobileEyes commands. Integrity and availability attacks caused sensitive information on the robot to be hijacked. To mitigate security threats, we provide possible mitigation techniques and suggestions to raise awareness of threats on the robotic platforms, especially when the robots are involved in critical missions or applications. PMID:29883403

  20. Facial injuries following hyena attack in rural eastern Ethiopia.

    PubMed

    Fell, M J; Ayalew, Y; McClenaghan, F C; McGurk, M

    2014-12-01

    Hyenas are effective hunters and will consider humans as potential prey if the need and opportunity arise. This study describes the circumstances of hyena attacks, the patterns of injuries sustained, and reconstruction in a resource-poor setting. As part of a charitable surgical mission to Ethiopia in 2012, 45 patients with facial deformities were reviewed, of whom four were victims of hyena attacks. A semi-structured interview was performed to ascertain the circumstances of the attack and the subsequent consequences. The age of the victims at the time of attack varied from 5 to 50 years. The attacks occurred when the victims were alone and vulnerable and took place in outdoor open spaces, during the evening or at night. The initial lunge was made to the facial area; if the jaws closed on the facial bones they were crushed, but in all cases the soft tissues were grasped and torn from the underlying bone. Reconstruction was dictated by the extent of soft tissue loss but could normally be obtained by use of local or regional flaps. Hyenas have been shown to attack humans in a predictable way and cause injuries that typically involve the soft tissues of the face. Copyright © 2014 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  1. Brain Circulation during Panic Attack: A Transcranial Doppler Study with Clomipramine Challenge.

    PubMed

    Rotella, Francesco; Marinoni, Marinella; Lejeune, Francesca; Alari, Fabiana; Depinesi, Daniela; Cosci, Fiammetta; Faravelli, Carlo

    2014-01-01

    Introduction. Cerebral blood flow has been well studied in patients with panic disorder, but only few studies analyzed the mechanisms underlying the onset of a panic attack. The aim of the present study was to monitor the cerebral hemodynamics modifications during a panic attack. Materials and Methods. 10 panic disorder patients with recent onset, fully drug naïve, were compared to 13 patients with panic disorder with a previous history of treatment and to 14 controls. A continuous bilateral monitoring of mean flow velocities in right and left middle cerebral arteries was performed by transcranial Doppler. Clomipramine was chosen as challenge. Results. Eight out of 10 patients drug naïve and 6 control subjects out of 13 had a full blown panic attack during the test, whereas none of the patients with a history of treatment panicked. The occurrence of a panic attack was accompanied by a rapid decrease of flow velocities in both right and left middle cerebral arteries. Discussion. The bilateral acute decrease of mean flow velocity during a panic attack suggests the vasoconstriction of the microcirculation of deep brain structures perfused by middle cerebral arteries and involved in the so-called "fear circuitry," thus suggesting that cerebral homeostatic dysfunctions seem to have a key role in the onset of a panic attack.

  2. A critical review of the field application of a mathematical model of malaria eradication

    PubMed Central

    Nájera, J. A.

    1974-01-01

    A malaria control field research trial in northern Nigeria was planned with the aid of a computer simulation based on Macdonald's mathematical model of malaria epidemiology. Antimalaria attack was based on a combination of mass drug administration (chloroquine and pyrimethamine) and DDT house spraying. The observed results were at great variance with the predictions of the model. The causes of these discrepancies included inadequate estimation of the model's basic variables, and overestimation, in planning the simulation, of the effects of the attack measures and of the degree of perfection attainable by their application. The discrepancies were to a great extent also due to deficiencies in the model. An analysis is made of those considered to be the most important. It is concluded that research efforts should be encouraged to increase our knowledge of the basic epidemiological factors, their variation and correlations, and to formulate more realistic and useful theoretical models. PMID:4156197

  3. Rabbit and Nonhuman Primate Models of Toxin-Targeting Human Anthrax Vaccines

    PubMed Central

    Phipps, Andrew J.; Premanandan, Christopher; Barnewall, Roy E.; Lairmore, Michael D.

    2004-01-01

    The intentional use of Bacillus anthracis, the etiological agent of anthrax, as a bioterrorist weapon in late 2001 made our society acutely aware of the importance of developing, testing, and stockpiling adequate countermeasures against biological attacks. Biodefense vaccines are an important component of our arsenal to be used during a biological attack. However, most of the agents considered significant threats either have been eradicated or rarely infect humans alive today. As such, vaccine efficacy cannot be determined in human clinical trials but must be extrapolated from experimental animal models. This article reviews the efficacy and immunogenicity of human anthrax vaccines in well-defined animal models and the progress toward developing a rugged immunologic correlate of protection. The ongoing evaluation of human anthrax vaccines will be dependent on animal efficacy data in the absence of human efficacy data for licensure by the U.S. Food and Drug Administration. PMID:15590776

  4. Potential for Controlling Cholera Using a Ring Vaccination Strategy: Re-analysis of Data from a Cluster-Randomized Clinical Trial

    PubMed Central

    Ali, Mohammad; Luquero, Francisco J.; Kim, Deok Ryun; Park, Je Yeon; Digilio, Laura; Manna, Byomkesh; Kanungo, Suman; Dutta, Shanta; Sur, Dipika; Bhattacharya, Sujit K.

    2016-01-01

    Introduction Vaccinating a buffer of individuals around a case (ring vaccination) has the potential to target those who are at highest risk of infection, reducing the number of doses needed to control a disease. We explored the potential vaccine effectiveness (VE) of oral cholera vaccines (OCVs) for such a strategy. Methods and Findings This analysis uses existing data from a cluster-randomized clinical trial in which OCV or placebo was given to 71,900 participants in Kolkata, India, from 27 July to 10 September 2006. Cholera surveillance was then conducted on 144,106 individuals living in the study area, including trial participants, for 5 y following vaccination. First, we explored the risk of cholera among contacts of cholera patients, and, second, we measured VE among individuals living within 25 m of cholera cases between 8 and 28 d after onset of the index case. For the first analysis, individuals living around each index case identified during the 5-y period were assembled using a ring to define cohorts of individuals exposed to cholera index cases. An index control without cholera was randomly selected for each index case from the same population, matched by age group, and individuals living around each index control were assembled using a ring to define cohorts not exposed to cholera cases. Cholera attack rates among the exposed and non-exposed cohorts were compared using different distances from the index case/control to define the rings and different time frames to define the period at risk. For the VE analysis, the exposed cohorts were further stratified according to the level of vaccine coverage into high and low coverage strata. Overall VE was assessed by comparing the attack rates between high and low vaccine coverage strata irrespective of individuals’ vaccination status, and indirect VE was assessed by comparing the attack rates among unvaccinated members between high and low vaccine coverage strata. Cholera risk among the cohort exposed to cholera cases was 5–11 times higher than that among the cohort not exposed to cholera cases. The risk gradually diminished with an increase in distance and time. The overall and indirect VE measured between 8 and 28 d after exposure to a cholera index case during the first 2 y was 91% (95% CI 62%–98%) and 93% (95% CI 44%–99%), respectively. VE persisted for 5 y after vaccination and was similar whether the index case was a young child (<5 y) or was older. Of note, this study was a reanalysis of a cholera vaccine trial that used two doses; thus, a limitation of the study relates to the assumption that a single dose, if administered quickly, will induce a similar level of total and indirect protection over the short term as did two doses. Conclusions These findings suggest that high-level protection can be achieved if individuals living close to cholera cases are living in a high coverage ring. Since this was an observational study including participants who had received two doses of vaccine (or placebo) in the clinical trial, further studies are needed to determine whether a ring vaccination strategy, in which vaccine is given quickly to those living close to a case, is feasible and effective. Trial registration ClinicalTrials.gov NCT00289224 PMID:27622507

  5. Practical Tests with the "auto Control Slot." Part II : Discussion

    NASA Technical Reports Server (NTRS)

    Lachmann, G

    1930-01-01

    For some time the D.V.L. has been investigating the question of applicability of Handley Page slotted wings to German airplanes. Comparitive gliding tests were made with open and closed slots on an Albatros L 75 airplane equipped with the Handley Page "auto control slots." This investigation served to determine the effect of the auto control slot on the properties and performances of airplanes at large angles of attack. The most important problems were whether the angle of glide at small angles of attack can be increased by the adoption of the auto control slot and, in particular, as to whether the flight characteristics at large angles of attack are improved thereby and equilibrium in gliding flight is guaranteed even at larger than ordinary angles of attack.

  6. Practical Tests with the "auto Control Slot." Part I : Lecture

    NASA Technical Reports Server (NTRS)

    Lachmann, G

    1930-01-01

    For some time the D.V.L. has been investigating the question of applicability of Handley Page slotted wings to German airplanes. Comparitive gliding tests were made with open and closed slots on an Albatros L 75 airplane equipped with the Handley Page "auto control slots." This investigation served to determine the effect of the auto control slot on the properties and performances of airplanes at large angles of attack. The most important problems were whether the angle of glide at small angles of attack can be increased by the adoption of the auto control slot and, in particular, as to whether the flight characteristics at large angles of attack are improved thereby and equilibrium in gliding flight is guaranteed even at larger than ordinary angles of attack.

  7. Comparison of Force and Moment Coefficients for the Same Test Article in Multiple Wind Tunnels

    NASA Technical Reports Server (NTRS)

    Deloach, Richard

    2013-01-01

    This paper compares the results of force and moment measurements made on the same test article and with the same balance in three transonic wind tunnels. Comparisons are made for the same combination of Reynolds number, Mach number, sideslip angle, control surface configuration, and angle of attack range. Between-tunnel force and moment differences are quantified. An analysis of variance was performed at four unique sites in the design space to assess the statistical significance of between-tunnel variation and any interaction with angle of attack. Tunnel to tunnel differences too large to attribute to random error were detected were observed for all forces and moments. In some cases these differences were independent of angle of attack and in other cases they changed with angle of attack.

  8. Foam as a Fire Suppressant: An Evaluation

    Treesearch

    Paul Schlobohm; Ron Rochna

    1987-01-01

    The ability of fire suppressant foams to improve ground-applied fire control efforts was evaluated. Foaming agents and foam-generating systems were examined. Performance evaluations were made for direct attack, indirect attack, and mop-up. Foam was determined to suppress and repel fire in situations where water did not. Cost comparisons of mop-up work showed straight...

  9. The Use of Paradoxical Intention in the Treatment of Panic Attacks.

    ERIC Educational Resources Information Center

    Dattilio, Frank M.

    1987-01-01

    Discusses the counseling use of paradoxical intention, in which clients are told to perform responses that seem incompatible with the goal for which they are seeking help. The use of paradoxical intention in the treatment of panic attacks is described and a case example is included. The nature and implementation of the technique are discussed.…

  10. The effects of scene content parameters, compression, and frame rate on the performance of analytics systems

    NASA Astrophysics Data System (ADS)

    Tsifouti, A.; Triantaphillidou, S.; Larabi, M. C.; Doré, G.; Bilissi, E.; Psarrou, A.

    2015-01-01

    In this investigation we study the effects of compression and frame rate reduction on the performance of four video analytics (VA) systems utilizing a low complexity scenario, such as the Sterile Zone (SZ). Additionally, we identify the most influential scene parameters affecting the performance of these systems. The SZ scenario is a scene consisting of a fence, not to be trespassed, and an area with grass. The VA system needs to alarm when there is an intruder (attack) entering the scene. The work includes testing of the systems with uncompressed and compressed (using H.264/MPEG-4 AVC at 25 and 5 frames per second) footage, consisting of quantified scene parameters. The scene parameters include descriptions of scene contrast, camera to subject distance, and attack portrayal. Additional footage, including only distractions (no attacks) is also investigated. Results have shown that every system has performed differently for each compression/frame rate level, whilst overall, compression has not adversely affected the performance of the systems. Frame rate reduction has decreased performance and scene parameters have influenced the behavior of the systems differently. Most false alarms were triggered with a distraction clip, including abrupt shadows through the fence. Findings could contribute to the improvement of VA systems.

  11. Aerocapture Guidance Performance for the Neptune Orbiter

    NASA Technical Reports Server (NTRS)

    Masciarelli, James P.; Westhelle, Carlos H.; Graves, Claude A.

    2004-01-01

    A performance evaluation of the Hybrid Predictor corrector Aerocapture Scheme (HYPAS) guidance algorithm for aerocapture at Neptune is presented in this paper for a Mission to Neptune and the Neptune moon Triton'. This mission has several challenges not experienced in previous aerocapture guidance assessments. These challengers are a very high Neptune arrival speed, atmospheric exit into a high energy orbit about Neptune, and a very high ballistic coefficient that results in a low altitude acceleration capability when combined with the aeroshell LD. The evaluation includes a definition of the entry corridor, a comparison to the theoretical optimum performance, and guidance responses to variations in atmospheric density, aerodynamic coefficients and flight path angle for various vehicle configurations (ballistic numbers). The benefits of utilizing angle-of-attack modulation in addition to bank angle modulation to improve flight performance is also discussed. The results show that despite large sensitivities in apoapsis targeting, the algorithm performs within the allocated AV budget for the Neptune mission bank angle only modulation. The addition of angle-of-attack modulation with as little as 5 degrees of amplitude significantly improves the scatter in final orbit apoapsis. Although the angle-of-attack modulation complicates the vehicle design, the performance enhancement reduces aerocapture risk and reduces the propellant consumption needed to reach the high energy target orbit for a conventional propulsion system.

  12. Generalized watermarking attack based on watermark estimation and perceptual remodulation

    NASA Astrophysics Data System (ADS)

    Voloshynovskiy, Sviatoslav V.; Pereira, Shelby; Herrigel, Alexander; Baumgartner, Nazanin; Pun, Thierry

    2000-05-01

    Digital image watermarking has become a popular technique for authentication and copyright protection. For verifying the security and robustness of watermarking algorithms, specific attacks have to be applied to test them. In contrast to the known Stirmark attack, which degrades the quality of the image while destroying the watermark, this paper presents a new approach which is based on the estimation of a watermark and the exploitation of the properties of Human Visual System (HVS). The new attack satisfies two important requirements. First, image quality after the attack as perceived by the HVS is not worse than the quality of the stego image. Secondly, the attack uses all available prior information about the watermark and cover image statistics to perform the best watermark removal or damage. The proposed attack is based on a stochastic formulation of the watermark removal problem, considering the embedded watermark as additive noise with some probability distribution. The attack scheme consists of two main stages: (1) watermark estimation and partial removal by a filtering based on a Maximum a Posteriori (MAP) approach; (2) watermark alteration and hiding through addition of noise to the filtered image, taking into account the statistics of the embedded watermark and exploiting HVS characteristics. Experiments on a number of real world and computer generated images show the high efficiency of the proposed attack against known academic and commercial methods: the watermark is completely destroyed in all tested images without altering the image quality. The approach can be used against watermark embedding schemes that operate either in coordinate domain, or transform domains like Fourier, DCT or wavelet.

  13. Necessary detection efficiencies for secure quantum key distribution and bound randomness

    NASA Astrophysics Data System (ADS)

    Acín, Antonio; Cavalcanti, Daniel; Passaro, Elsa; Pironio, Stefano; Skrzypczyk, Paul

    2016-01-01

    In recent years, several hacking attacks have broken the security of quantum cryptography implementations by exploiting the presence of losses and the ability of the eavesdropper to tune detection efficiencies. We present a simple attack of this form that applies to any protocol in which the key is constructed from the results of untrusted measurements performed on particles coming from an insecure source or channel. Because of its generality, the attack applies to a large class of protocols, from standard prepare-and-measure to device-independent schemes. Our attack gives bounds on the critical detection efficiencies necessary for secure quantum key distribution, which show that the implementation of most partly device-independent solutions is, from the point of view of detection efficiency, almost as demanding as fully device-independent ones. We also show how our attack implies the existence of a form of bound randomness, namely nonlocal correlations in which a nonsignalling eavesdropper can find out a posteriori the result of any implemented measurement.

  14. Vulnerabilities in GSM technology and feasibility of selected attacks

    NASA Astrophysics Data System (ADS)

    Voznak, M.; Prokes, M.; Sevcik, L.; Frnda, J.; Toral-Cruz, Homer; Jakovlev, Sergej; Fazio, Peppino; Mehic, M.; Mikulec, M.

    2015-05-01

    Global System for Mobile communication (GSM) is the most widespread technology for mobile communications in the world and serving over 7 billion users. Since first publication of system documentation there has been notified a potential safety problem's occurrence. Selected types of attacks, based on the analysis of the technical feasibility and the degree of risk of these weaknesses, were implemented and demonstrated in laboratory of the VSB-Technical University of Ostrava, Czech Republic. These vulnerabilities were analyzed and afterwards possible attacks were described. These attacks were implemented using open-source tools, software programmable radio USRP (Universal Software RadioPeripheral) and DVB-T (Digital Video Broadcasting - Terrestrial) receiver. GSM security architecture is being scrutinized since first public releases of its specification mainly pointing out weaknesses in authentication and ciphering mechanisms. This contribution also summarizes practically proofed and used scenarios that are performed using opensource software tools and variety of scripts mostly written in Python. Main goal of this paper is in analyzing security issues in GSM network and practical demonstration of selected attacks.

  15. A robust trust establishment scheme for wireless sensor networks.

    PubMed

    Ishmanov, Farruh; Kim, Sung Won; Nam, Seung Yeob

    2015-03-23

    Security techniques like cryptography and authentication can fail to protect a network once a node is compromised. Hence, trust establishment continuously monitors and evaluates node behavior to detect malicious and compromised nodes. However, just like other security schemes, trust establishment is also vulnerable to attack. Moreover, malicious nodes might misbehave intelligently to trick trust establishment schemes. Unfortunately, attack-resistance and robustness issues with trust establishment schemes have not received much attention from the research community. Considering the vulnerability of trust establishment to different attacks and the unique features of sensor nodes in wireless sensor networks, we propose a lightweight and robust trust establishment scheme. The proposed trust scheme is lightweight thanks to a simple trust estimation method. The comprehensiveness and flexibility of the proposed trust estimation scheme make it robust against different types of attack and misbehavior. Performance evaluation under different types of misbehavior and on-off attacks shows that the detection rate of the proposed trust mechanism is higher and more stable compared to other trust mechanisms.

  16. Tables for Supersonic Flow of Helium Around Right Circular Cones at Zero Angle of Attack

    NASA Technical Reports Server (NTRS)

    Sims, J. L.

    1973-01-01

    The results of the calculation of supersonic flow of helium about right circular cones at zero angle of attack are presented in tabular form. The calculations were performed using the Taylor-Maccoll theory. Numerical integrations were performed using a Runge-Kutta method for second-order differential equations. Results were obtained for cone angles from 2.5 to 30 degrees in regular increments of 2.5 degrees. In all calculations the desired free-stream Mach number was obtained to five or more significant figures.

  17. AFRPL Graphite Performance Prediction Program. Improved Capability for the Design and Ablation Performance Prediction of Advanced Air Force Solid Propellant Rocket Nozzles

    DTIC Science & Technology

    1976-12-01

    corrosive attack by both acids and alkali and, in addition, is provided with a special Dynel veil for protection against fluoride attack. 3.1.4...throat region, namely , the entrance, center, and exit. In addition, at each station, the diameters were determined at two angular positions 90° apart. The...characterization test matrix. 3.2.1.1 Rocket Motor Environments Rocket motor environments were based on three advanced MX propellants, namely , * XLDB * HTPB * PEG

  18. The effectiveness of ibuprofen and lorazepam combination therapy in treating the symptoms of acute Migraine: A randomized clinical trial.

    PubMed

    Rad, Reza Ebrahimi; Ghaffari, Fatemeh; Fotokian, Zahra; Ramezani, Azadeh

    2017-03-01

    Migraine is a common, episodic and debilitating disease. The migraineur not only suffers from pain, but also lives with a diminished to poor quality of life. Several medicinal therapies are used to abate the debilitating symptoms of this disease. The present study was conducted to determine the effectiveness of Ibuprofen and Lorazepam combination therapy in treating the symptoms of acute migraine. The present randomized clinical trial study used the pretest-posttest design with three comparison treatments, to examine 90 patients with an average of two to six attacks per month and an initial diagnosis of migraine based on the International Headache Society (HIS) criteria. The study was conducted on patients during the first half of 2014 with a diagnosis of acute migraine attack who were referred to Babol Ayatollah Rouhani Hospital in Iran. The patients were randomly divided into three groups of 30. The first group was administered 200 mg Ibuprofen capsules, the second group 400 mg Ibuprofen capsules and the third group a combination of 200 mg Ibuprofen capsules and 1 mg Lorazepam tablets. The medications were taken in the presence of the researcher. A checklist was used to assess the severity of headache and other migraine symptoms such as nausea, vomiting, photophobia and phonophobia in the patients, before and two hours after the intervention. Data were analyzed in SPSS-18 using the Mann-Whitney test, the McNemar test, Wilcoxon's test, the NOVA and the Chi-squared test at the significance level of p<0.05, and power analysis with 30 patients in each group to perform this study was 0.8(1-β). The mean age of participants was reported as 52±8 years and the condition was more frequent in women (56%). All three treatment regimens reduced the severity of headache significantly in the patients (p<0.001); nevertheless, the combination therapy used, produced the lowest mean severity of headache (p<0.001). The highest reduction in nausea and vomiting was (3.3%). None of the patients in either of the three groups reported phonophobia after the intervention, but only the patients in the combination therapy group reported no instance of photophobia. Given the greater effectiveness of combination therapy with Ibuprofen and Lorazepam in alleviating the symptoms of acute migraine compared to single-drug treatments with Ibuprofen, Lorazepam is recommended to be used as a first line treatment for acute migraine. The trial was registered at the Thai Clinical Trials Registry (TCTR) (http://www.clinicaltrials.in.th/) with the ID: TCTR20160927003. The authors received no financial support for the research, authorship, and/or publication of this article.

  19. Community-Based Intervention to Improve Cardiometabolic Targets in Patients With Stroke: A Randomized Controlled Trial.

    PubMed

    Olaiya, Muideen T; Cadilhac, Dominique A; Kim, Joosup; Nelson, Mark R; Srikanth, Velandai K; Gerraty, Richard P; Bladin, Christopher F; Fitzgerald, Sharyn M; Phan, Thanh; Frayne, Judith; Thrift, Amanda G

    2017-09-01

    Many guidelines for secondary prevention of stroke focus on controlling cardiometabolic risk factors. We investigated the effectiveness of a management program for attaining cardiometabolic targets in survivors of stroke/transient ischemic attack. Randomized controlled trial of survivors of stroke/transient ischemic attack aged ≥18 years. General practices were randomized to usual care (control) or an intervention comprising specialist review of care plans and nurse education in addition to usual care. The outcome is attainment of pre-defined cardiometabolic targets based on Australian guidelines. Multivariable regression was undertaken to determine efficacy and identify factors associated with attaining targets. Overall, 283 subjects were randomized to the intervention and 280 to controls. Although we found no between-group difference in overall cardiometabolic targets achieved at 12 months, the intervention group more often achieved control of low-density lipoprotein cholesterol (odds ratio, 1.97; 95% confidence interval, 1.18-3.29) than controls. At 24 months, no between-group differences were observed. Medication adherence was ≥80% at follow-up, but uptake of lifestyle/behavioral habits was poor. Older age, being male, being married/living with partner, and having greater functional ability or a history of diabetes mellitus were associated with attaining targets. The intervention in this largely negative trial only had a detectable effect on attaining target for lipids but not for other factors at 12 months or any factor at 24 months. This limited effect may be attributable to inadequate uptake of behavioral/lifestyle interventions, highlighting the need for new or better approaches to achieve meaningful behavioral change. URL: http://www.clinicaltrials.gov. Unique identifier: ACTRN12608000166370. © 2017 American Heart Association, Inc.

  20. Validation of Heart Failure Events in the Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) Participants Assigned to Doxazosin and Chlorthalidone

    PubMed Central

    Piller, Linda B; Davis, Barry R; Cutler, Jeffrey A; Cushman, William C; Wright, Jackson T; Williamson, Jeff D; Leenen, Frans HH; Einhorn, Paula T; Randall, Otelio S; Golden, John S; Haywood, L Julian

    2002-01-01

    Background The Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial (ALLHAT) is a randomized, double-blind, active-controlled trial designed to compare the rate of coronary heart disease events in high-risk hypertensive participants initially randomized to a diuretic (chlorthalidone) versus each of three alternative antihypertensive drugs: alpha-adrenergic blocker (doxazosin), ACE-inhibitor (lisinopril), and calcium-channel blocker (amlodipine). Combined cardiovascular disease risk was significantly increased in the doxazosin arm compared to the chlorthalidone arm (RR 1.25; 95% CI, 1.17–1.33; P < .001), with a doubling of heart failure (fatal, hospitalized, or non-hospitalized but treated) (RR 2.04; 95% CI, 1.79–2.32; P < .001). Questions about heart failure diagnostic criteria led to steps to validate these events further. Methods and Results Baseline characteristics (age, race, sex, blood pressure) did not differ significantly between treatment groups (P < .05) for participants with heart failure events. Post-event pharmacologic management was similar in both groups and generally conformed to accepted heart failure therapy. Central review of a small sample of cases showed high adherence to ALLHAT heart failure criteria. Of 105 participants with quantitative ejection fraction measurements provided, (67% by echocardiogram, 31% by catheterization), 29/46 (63%) from the chlorthalidone group and 41/59 (70%) from the doxazosin group were at or below 40%. Two-year heart failure case-fatalities (22% and 19% in the doxazosin and chlorthalidone groups, respectively) were as expected and did not differ significantly (RR 0.96; 95% CI, 0.67–1.38; P = 0.83). Conclusion Results of the validation process supported findings of increased heart failure in the ALLHAT doxazosin treatment arm compared to the chlorthalidone treatment arm. PMID:12459039

  1. Efficacy of Noninvasive Brain Stimulation on Pain Control in Migraine Patients: A Systematic Review and Meta-Analysis.

    PubMed

    Shirahige, Lívia; Melo, Lorena; Nogueira, Fernanda; Rocha, Sérgio; Monte-Silva, Kátia

    2016-11-01

    To evaluate the efficacy of noninvasive brain stimulation (NIBS) on pain control in migraine patients. Recent studies have used NIBS as an abortive and prophylactic treatment for migraine; however, its efficacy regarding meaningful clinical effects remains to be critically analyzed. Systematic review of controlled clinical trials. Searches were conducted in six databases: MEDLINE (via PubMed), LILACS (via BIREME), CINAHL (via EBSCO), Scopus (via EBSCO), Web of Science, and CENTRAL. Two independent authors searched for randomized controlled clinical trials published through until January 2016 that involved the use of transcranial direct current stimulation (tDCS) and transcranial magnetic stimulation (TMS) in migraineurs. Studies which met the eligibility criteria were assessed and methodological quality was examined using the Cochrane tool for assessing risk of bias. Information about pain intensity (primary outcome), migraine attacks, painkiller intake, and adverse effects were extracted. Eight studies were included in the quantitative analysis with 153 migraine patients that received NIBS and 143 sham NIBS. In overall meta-analysis, we did not find significant results for pain intensity (SMD: -0.61; CI: -1.35 to 0.13; P = .11), for migraine attacks (SMD: -0.44; 95%; CI: -1.15 to 0.26; P = .22), and for painkiller intake (SMD: -0.57; 95% CI: -1.21 to 0.07; P = .08). However, subgroup analysis considering only tDCS effects have demonstrated a decrease for pain intensity (SMD: -0.91; 95% CI: -1.79 to -0.03; P = .04), migraine attacks (SMD: -0.75; 95% CI: -1.25 to -0.24; P = .004), and painkiller intake (SMD: -0.64; 95% CI: -1.21 to -0.07; P = .03). Subgroup analysis for TMS did not reveal significant effects for any outcome. Low or very low quality of evidence suggests that our primary outcome evaluation failed to find support for the superiority of NIBS over sham treatment. Although, subgroup analysis reveals that tDCS have moderate to high effects and could be a promising nonpharmacological alternative to pain control, mainly for painkiller intake reduction. However, there is a need for larger controlled trials with methodological rigor, which could increase the power of result inference. © 2016 American Headache Society.

  2. The ins and outs of terrorist bus explosions: injury profiles of on-board explosions versus explosions occurring adjacent to a bus.

    PubMed

    Golan, Ron; Soffer, Dror; Givon, Adi; Peleg, Kobi

    2014-01-01

    Terrorist explosions occurring in varying settings have been shown to lead to significantly different injury patterns among the victims, with more severe injuries generally arising in confined space attacks. Increasing numbers of terrorist attacks have been targeted at civilian buses, yet most studies focus on events in which the bomb was detonated within the bus. This study focuses on the injury patterns and hospital utilisation among casualties from explosive terrorist bus attacks with the bomb detonated either within a bus or adjacent to a bus. All patients hospitalised at six level I trauma centres and four large regional trauma centres following terrorist explosions that occurred in and adjacent to buses in Israel between November 2000 and August 2004 were reviewed. Injury severity scores (ISS) were used to assess severity. Hospital utilisation data included length of hospital stay, surgical procedures performed, and intensive care unit (ICU) admission. The study included 262 victims of 22 terrorist attacks targeted at civilian bus passengers and drivers; 171 victims were injured by an explosion within a bus (IB), and 91 were injured by an explosion adjacent to a bus (AB). Significant differences were noted between the groups, with the IB population having higher ISS scores, more primary blast injury, more urgent surgical procedures performed, and greater ICU utilisation. Both groups had percentages of nearly 20% for burn injury, had high percentages of injuries to the head/neck, and high percentages of surgical wound and burn care. Explosive terrorist attacks detonated within a bus generate more severe injuries among the casualties and require more urgent surgical and intensive level care than attacks occurring adjacent to a bus. The comparison and description of the outcomes to these terrorist attacks should aid in the preparation and response to such devastating events. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Behavioral Strategies of Phorid Parasitoids and Responses of Their Hosts, the Leaf-Cutting Ants

    PubMed Central

    Elizalde, Luciana; Folgarait, Patricia Julia

    2012-01-01

    Host-searching and oviposition behaviors of parasitoids, and defensive responses of the hosts, are fundamental in shaping the ecology of host-parasitoid interactions. In order to uncover key behavioral features for the little known interactions between phorid parasitoids (Diptera: Phoridae) and their leaf-cutting ant hosts (Formicidae: Attini), host-related behavioral strategies (i.e., host searching and oviposition) for 13 phorid species, and host defensive responses (i.e., hitchhikers and particular body postures) for 11 ant species, were studied. Data was collected at 14 localities, one of them characterized by its high species richness for this host-parasitoid system. Phorid species showed both great variation and specificity in attacking behaviors. Some chose their hosts using either an ambush or an actively searching strategy, while some species attacked ants on different body parts, and specialized on ants performing different tasks, such as when ants were foraging, removing wastes to refuse piles, or repairing the nest. Combining all the behaviors recorded, most phorid species differed in performance in at least one, making it possible to recognize species in the field through their behavior. Phorid species that attacked hosts with greater activity levels showed overall higher attack rates, although there was no significant correlation between attack rates by most phorid species and ant activity outside the nest while parasitoids were attacking. The presence of phorids was a significant determinant for the presence of defensive behaviors by the ants. Although ant species varied in the incidence levels of these defensive behaviors, most ant species reacted against different phorids by utilizing similar behaviors, in contrast to what parasitoids do. General features of the observed phorid-ant interactions were parasitoid specialization and corresponding high interspecific variation in their behaviors, while their hosts showed generalized responses to attacks with high intraspecific variation. Behavioral patterns as well as specific features of these ant-parasitoid interactions are described, and their ecological importance discussed. PMID:23448343

  4. Risk factors for hypertensive attack during pheochromocytoma resection

    PubMed Central

    Kwon, Se Yun; Lee, Kyung Seop; Lee, Jun Nyung; Ha, Yun-Sok; Choi, Seock Hwan; Kim, Hyun Tae; Kim, Tae-Hwan; Yoo, Eun Sang

    2016-01-01

    Purpose We aimed to retrospectively evaluate the risk factors for hypertensive attack during adrenalectomy in patients with pheochromocytoma. Despite the development of newer surgical and anesthetic techniques for the management of pheochromocytoma, intraoperative hypertensive attack continues to present a challenge. Materials and Methods Data from 53 patients diagnosed with pheochromocytoma at Kyungpook National Uriversity Medical Center between January 2000 and June 2012 were retrospectively analyzed. The subjects were divided into 2 groups depending on the presence or absence of hypertensive attack at the time of surgery. Patient demographic characteristics and preoperative evaluations were assessed for their prognostic relevance with respect to hypertensive attack. A univariate analysis was conducted, and a multivariate logistic regression analysis was also performed. Results In the univariate analysis, systolic blood pressure at presentation, preoperative hormonal status (including epinephrine, norepinephrine, vanillylmandelic acid, and metanephrine levels in a 24-hour urine sample), tumor size, and postoperative systolic blood pressure were significantly associated with the development of hypertensive attack. In the multivariate analysis, preoperative epinephrine level and tumor size were independent factors that predicted hypertensive attack. The highest odds ratio for tumor size (2.169) was obtained at a cutoff value of 4.25 cm and the highest odds ratio for preoperative epinephrine (1.020) was obtained at a cutoff value of 166.3 µg/d. Conclusions In this study, a large tumor size and an elevated preoperative urinary epinephrine level were risk factors for intraoperative hypertensive attack in patients with pheochromocytoma. PMID:27194549

  5. Turbulent flow and heat transfer of Water/Al2O3 nanofluid inside a rectangular ribbed channel

    NASA Astrophysics Data System (ADS)

    Parsaiemehr, Mohammad; Pourfattah, Farzad; Akbari, Omid Ali; Toghraie, Davood; Sheikhzadeh, Ghanbarali

    2018-02-01

    In present study, the turbulent flow and heat transfer of Water/Al2O3 nanofluid inside a rectangular channel have been numerically simulated. The main purpose of present study is investigating the effect of attack angle of inclined rectangular rib, Reynolds number and volume fraction of nanoparticles on heat transfer enhancement. For this reason, the turbulent flow of nanofluid has been simulated at Reynolds numbers ranging from 15000 to 30000 and volume fractions of nanoparticles from 0 to 4%. The changes attack angle of ribs have been investigated ranging from 0 to 180°. The results show that, the changes of attack angle of ribs, due to the changes of flow pattern and created vortexes inside the channel, have significant effect on fluid mixing. Also, the maximum rate of heat transfer enhancement accomplishes in attack angle of 60°. In Reynolds numbers of 15000, 20000 and 30000 and attack angle of 60°, comparing to the attack angle of 0°, the amount of Nusselt number enhances to 2.37, 1.96 and 2 times, respectively. Also, it can be concluded that, in high Reynolds numbers, by using ribs and nanofluid, the performance evaluation criterion improves.

  6. Robust and Blind 3D Mesh Watermarking in Spatial Domain Based on Faces Categorization and Sorting

    NASA Astrophysics Data System (ADS)

    Molaei, Amir Masoud; Ebrahimnezhad, Hossein; Sedaaghi, Mohammad Hossein

    2016-06-01

    In this paper, a 3D watermarking algorithm in spatial domain is presented with blind detection. In the proposed method, a negligible visual distortion is observed in host model. Initially, a preprocessing is applied on the 3D model to make it robust against geometric transformation attacks. Then, a number of triangle faces are determined as mark triangles using a novel systematic approach in which faces are categorized and sorted robustly. In order to enhance the capability of information retrieval by attacks, block watermarks are encoded using Reed-Solomon block error-correcting code before embedding into the mark triangles. Next, the encoded watermarks are embedded in spherical coordinates. The proposed method is robust against additive noise, mesh smoothing and quantization attacks. Also, it is stout next to geometric transformation, vertices and faces reordering attacks. Moreover, the proposed algorithm is designed so that it is robust against the cropping attack. Simulation results confirm that the watermarked models confront very low distortion if the control parameters are selected properly. Comparison with other methods demonstrates that the proposed method has good performance against the mesh smoothing attacks.

  7. Impact of Degree Heterogeneity on Attack Vulnerability of Interdependent Networks

    NASA Astrophysics Data System (ADS)

    Sun, Shiwen; Wu, Yafang; Ma, Yilin; Wang, Li; Gao, Zhongke; Xia, Chengyi

    2016-09-01

    The study of interdependent networks has become a new research focus in recent years. We focus on one fundamental property of interdependent networks: vulnerability. Previous studies mainly focused on the impact of topological properties upon interdependent networks under random attacks, the effect of degree heterogeneity on structural vulnerability of interdependent networks under intentional attacks, however, is still unexplored. In order to deeply understand the role of degree distribution and in particular degree heterogeneity, we construct an interdependent system model which consists of two networks whose extent of degree heterogeneity can be controlled simultaneously by a tuning parameter. Meanwhile, a new quantity, which can better measure the performance of interdependent networks after attack, is proposed. Numerical simulation results demonstrate that degree heterogeneity can significantly increase the vulnerability of both single and interdependent networks. Moreover, it is found that interdependent links between two networks make the entire system much more fragile to attacks. Enhancing coupling strength between networks can greatly increase the fragility of both networks against targeted attacks, which is most evident under the case of max-max assortative coupling. Current results can help to deepen the understanding of structural complexity of complex real-world systems.

  8. A Chinese patent medicine Salvia miltiorrhiza depside salts for infusion combined with conventional treatment for patients with angina pectoris: A systematic review and meta-analysis of randomized controlled trials.

    PubMed

    Zhang, Yili; Xie, Yanming; Liao, Xing; Jia, Qiulei; Chai, Yan

    2017-02-15

    Currently, many trials have been conducted to investigate the beneficial and harmful effects of Salvia miltiorrhiza depside salts for infusion for treating patients with angina pectoris. It is important to systematically and criticallyevaluate the existing literature into providing a pooled effect to examine outcomes of angina pectoris with Salvia miltiorrhiza depside salts for infusion. A systematic review and meta-analysis were performed to determine the clinical curative effect and safety of Salvia miltiorrhiza depside salts for infusion for angina pectoris and provide clear evidence to inform clinical practice. The Cochrane Library, MEDLINE, EMBASE, and other four electronic Chinese databases were searched to identify relevant randomized controlled trials. Methodological quality and reporting quality of eligible studies was evaluated by using the Cochrane risk-of-bias tool and CONSORT for traditional Chinese medicine respectively. Meta-analysis was performed by RevMan 5.3 software. Fifty-six randomized controlled trials involving 5503 patients were included. Most of the trials were classified as having an unclear risk of bias because of poor reported methodology. The main outcomes are improvements in angina symptoms, ECG improvement and reduction of nitroglycerin use. CHD mortality or rate of CHD events was not reported in any trial. Meta-analysis showed that Salvia miltiorrhiza depside salts for infusion combined with conventional treatment was better than conventional treatment alone in improving angina symptoms (RR= 1.28, 95% CI 1.24 to 1.31, p < 0.00001), the frequency of angina attack (time/week)(WMD=-1.47, 95% CI -2.16 to -0.78), reducing clinical symptom scores (WMD=-0.55, 95% CI -0.57 to -0.53, p < 0.000011), increasing physical limitation scores (WMD= 7.68, 95% CI 1.48 to 13.88, p = 0.02), improving ECG (RR= 1.32,95% CI 1.27 to 1.38, p < 0.00001) and reducing dosage of nitroglycerin (RR= 1.50, 95% CI: 1.26 to 1.77, p < 0.00001). In addition, Egger's regression tests was found there was publication bias (Kendall' tau= 0.36, p < 0.01). The current systematic review indicates relevant evidence for Salvia miltiorrhiza depside salts for infusion combined with conventional treatments treating patient with angina pectoris. However, the results should be interpreted with caution due to the low methodological quality, the risk of publication bias, lack of important clinically relevant outcomes and inadequate reporting on adverse events of the included trials. International methodological and reporting standards could help researchers conduct well designed trials and generate better evidence for Salvia miltiorrhiza depside salts for infusion. Copyright © 2017 The Authors. Published by Elsevier GmbH.. All rights reserved.

  9. Off-Design Performance of a Streamline-Traced, External-Compression Supersonic Inlet

    NASA Technical Reports Server (NTRS)

    Slater, John W.

    2017-01-01

    A computational study was performed to explore the aerodynamic performance of a streamline-traced, external-compression inlet designed for Mach 1.664 at off-design conditions of freestream Mach number, angle-of-attack, and angle-of-sideslip. Serious degradation of the inlet performance occurred for negative angles-of-attack and angles-of-sideslip greater than 3 degrees. At low subsonic speeds, the swept leading edges of the inlet created a pair of vortices that propagated to the engine face. Increasing the bluntness of the cowl lip showed no real improvement in the inlet performance at the low speeds, but did improve the inlet performance at the design conditions. Reducing the inlet flow rate improved the inlet performance, but at the likely expense of reduced thrust of the propulsion system. Deforming the cowl lip for low-speed operation of the inlet increased the inlet capture area and improved the inlet performance.

  10. Spoof Detection for Finger-Vein Recognition System Using NIR Camera.

    PubMed

    Nguyen, Dat Tien; Yoon, Hyo Sik; Pham, Tuyen Danh; Park, Kang Ryoung

    2017-10-01

    Finger-vein recognition, a new and advanced biometrics recognition method, is attracting the attention of researchers because of its advantages such as high recognition performance and lesser likelihood of theft and inaccuracies occurring on account of skin condition defects. However, as reported by previous researchers, it is possible to attack a finger-vein recognition system by using presentation attack (fake) finger-vein images. As a result, spoof detection, named as presentation attack detection (PAD), is necessary in such recognition systems. Previous attempts to establish PAD methods primarily focused on designing feature extractors by hand (handcrafted feature extractor) based on the observations of the researchers about the difference between real (live) and presentation attack finger-vein images. Therefore, the detection performance was limited. Recently, the deep learning framework has been successfully applied in computer vision and delivered superior results compared to traditional handcrafted methods on various computer vision applications such as image-based face recognition, gender recognition and image classification. In this paper, we propose a PAD method for near-infrared (NIR) camera-based finger-vein recognition system using convolutional neural network (CNN) to enhance the detection ability of previous handcrafted methods. Using the CNN method, we can derive a more suitable feature extractor for PAD than the other handcrafted methods using a training procedure. We further process the extracted image features to enhance the presentation attack finger-vein image detection ability of the CNN method using principal component analysis method (PCA) for dimensionality reduction of feature space and support vector machine (SVM) for classification. Through extensive experimental results, we confirm that our proposed method is adequate for presentation attack finger-vein image detection and it can deliver superior detection results compared to CNN-based methods and other previous handcrafted methods.

  11. Spoof Detection for Finger-Vein Recognition System Using NIR Camera

    PubMed Central

    Nguyen, Dat Tien; Yoon, Hyo Sik; Pham, Tuyen Danh; Park, Kang Ryoung

    2017-01-01

    Finger-vein recognition, a new and advanced biometrics recognition method, is attracting the attention of researchers because of its advantages such as high recognition performance and lesser likelihood of theft and inaccuracies occurring on account of skin condition defects. However, as reported by previous researchers, it is possible to attack a finger-vein recognition system by using presentation attack (fake) finger-vein images. As a result, spoof detection, named as presentation attack detection (PAD), is necessary in such recognition systems. Previous attempts to establish PAD methods primarily focused on designing feature extractors by hand (handcrafted feature extractor) based on the observations of the researchers about the difference between real (live) and presentation attack finger-vein images. Therefore, the detection performance was limited. Recently, the deep learning framework has been successfully applied in computer vision and delivered superior results compared to traditional handcrafted methods on various computer vision applications such as image-based face recognition, gender recognition and image classification. In this paper, we propose a PAD method for near-infrared (NIR) camera-based finger-vein recognition system using convolutional neural network (CNN) to enhance the detection ability of previous handcrafted methods. Using the CNN method, we can derive a more suitable feature extractor for PAD than the other handcrafted methods using a training procedure. We further process the extracted image features to enhance the presentation attack finger-vein image detection ability of the CNN method using principal component analysis method (PCA) for dimensionality reduction of feature space and support vector machine (SVM) for classification. Through extensive experimental results, we confirm that our proposed method is adequate for presentation attack finger-vein image detection and it can deliver superior detection results compared to CNN-based methods and other previous handcrafted methods. PMID:28974031

  12. A Zonal Approach for the Solution of Coupled Euler and Potential Solutions of Flows with Complex Geometries.

    DTIC Science & Technology

    1987-06-01

    obtained from: A simple numerical intergration scheme is employed to perform the integral in Equations (B2) and (86) along the dividing streamline. A 11 4...angle of attack was small, the dividing streamline remained almost horizontal in this case. Results of a higher angle of attack case, in which the mesh

  13. Secure and Fair Cluster Head Selection Protocol for Enhancing Security in Mobile Ad Hoc Networks

    PubMed Central

    Paramasivan, B.; Kaliappan, M.

    2014-01-01

    Mobile ad hoc networks (MANETs) are wireless networks consisting of number of autonomous mobile devices temporarily interconnected into a network by wireless media. MANETs become one of the most prevalent areas of research in the recent years. Resource limitations, energy efficiency, scalability, and security are the great challenging issues in MANETs. Due to its deployment nature, MANETs are more vulnerable to malicious attack. The secure routing protocols perform very basic security related functions which are not sufficient to protect the network. In this paper, a secure and fair cluster head selection protocol (SFCP) is proposed which integrates security factors into the clustering approach for achieving attacker identification and classification. Byzantine agreement based cooperative technique is used for attacker identification and classification to make the network more attack resistant. SFCP used to solve this issue by making the nodes that are totally surrounded by malicious neighbors adjust dynamically their belief and disbelief thresholds. The proposed protocol selects the secure and energy efficient cluster head which acts as a local detector without imposing overhead to the clustering performance. SFCP is simulated in network simulator 2 and compared with two protocols including AODV and CBRP. PMID:25143986

  14. Secure and fair cluster head selection protocol for enhancing security in mobile ad hoc networks.

    PubMed

    Paramasivan, B; Kaliappan, M

    2014-01-01

    Mobile ad hoc networks (MANETs) are wireless networks consisting of number of autonomous mobile devices temporarily interconnected into a network by wireless media. MANETs become one of the most prevalent areas of research in the recent years. Resource limitations, energy efficiency, scalability, and security are the great challenging issues in MANETs. Due to its deployment nature, MANETs are more vulnerable to malicious attack. The secure routing protocols perform very basic security related functions which are not sufficient to protect the network. In this paper, a secure and fair cluster head selection protocol (SFCP) is proposed which integrates security factors into the clustering approach for achieving attacker identification and classification. Byzantine agreement based cooperative technique is used for attacker identification and classification to make the network more attack resistant. SFCP used to solve this issue by making the nodes that are totally surrounded by malicious neighbors adjust dynamically their belief and disbelief thresholds. The proposed protocol selects the secure and energy efficient cluster head which acts as a local detector without imposing overhead to the clustering performance. SFCP is simulated in network simulator 2 and compared with two protocols including AODV and CBRP.

  15. GNSS Spoofing Detection and Mitigation Based on Maximum Likelihood Estimation

    PubMed Central

    Li, Hong; Lu, Mingquan

    2017-01-01

    Spoofing attacks are threatening the global navigation satellite system (GNSS). The maximum likelihood estimation (MLE)-based positioning technique is a direct positioning method originally developed for multipath rejection and weak signal processing. We find this method also has a potential ability for GNSS anti-spoofing since a spoofing attack that misleads the positioning and timing result will cause distortion to the MLE cost function. Based on the method, an estimation-cancellation approach is presented to detect spoofing attacks and recover the navigation solution. A statistic is derived for spoofing detection with the principle of the generalized likelihood ratio test (GLRT). Then, the MLE cost function is decomposed to further validate whether the navigation solution obtained by MLE-based positioning is formed by consistent signals. Both formulae and simulations are provided to evaluate the anti-spoofing performance. Experiments with recordings in real GNSS spoofing scenarios are also performed to validate the practicability of the approach. Results show that the method works even when the code phase differences between the spoofing and authentic signals are much less than one code chip, which can improve the availability of GNSS service greatly under spoofing attacks. PMID:28665318

  16. GNSS Spoofing Detection and Mitigation Based on Maximum Likelihood Estimation.

    PubMed

    Wang, Fei; Li, Hong; Lu, Mingquan

    2017-06-30

    Spoofing attacks are threatening the global navigation satellite system (GNSS). The maximum likelihood estimation (MLE)-based positioning technique is a direct positioning method originally developed for multipath rejection and weak signal processing. We find this method also has a potential ability for GNSS anti-spoofing since a spoofing attack that misleads the positioning and timing result will cause distortion to the MLE cost function. Based on the method, an estimation-cancellation approach is presented to detect spoofing attacks and recover the navigation solution. A statistic is derived for spoofing detection with the principle of the generalized likelihood ratio test (GLRT). Then, the MLE cost function is decomposed to further validate whether the navigation solution obtained by MLE-based positioning is formed by consistent signals. Both formulae and simulations are provided to evaluate the anti-spoofing performance. Experiments with recordings in real GNSS spoofing scenarios are also performed to validate the practicability of the approach. Results show that the method works even when the code phase differences between the spoofing and authentic signals are much less than one code chip, which can improve the availability of GNSS service greatly under spoofing attacks.

  17. Simulating Effects of High Angle of Attack on Turbofan Engine Performance

    NASA Technical Reports Server (NTRS)

    Liu, Yuan; Claus, Russell W.; Litt, Jonathan S.; Guo, Ten-Huei

    2013-01-01

    A method of investigating the effects of high angle of attack (AOA) flight on turbofan engine performance is presented. The methodology involves combining a suite of diverse simulation tools. Three-dimensional, steady-state computational fluid dynamics (CFD) software is used to model the change in performance of a commercial aircraft-type inlet and fan geometry due to various levels of AOA. Parallel compressor theory is then applied to assimilate the CFD data with a zero-dimensional, nonlinear, dynamic turbofan engine model. The combined model shows that high AOA operation degrades fan performance and, thus, negatively impacts compressor stability margins and engine thrust. In addition, the engine response to high AOA conditions is shown to be highly dependent upon the type of control system employed.

  18. Controversies Regarding Management of Vesico-ureteric Reflux.

    PubMed

    Babu, Ramesh; Chowdhary, Sujit

    2017-07-01

    The primary goal in the management of a child with urinary tract infection (UTI) is to prevent recurrence of UTI and acquired renal damage. Approximately 15% of children develop renal scarring after a first episode of febrile UTI. Vesico-ureteric reflux (VUR) is diagnosed in 30-40% of children imaged after first febrile UTI. The 'top-down' approach involving ultrasound and dimercaptosuccinic acid scan (DMSA) first after an appropriate interval following UTI, can help in avoiding voiding cystourethrogram (VCUG), an invasive test with higher radiation exposure. The majority view remains that VCUG should be done after the second attack of UTI in girls and first attack of UTI in boys. Although the evidence in favour of antibiotic prophylaxis remains doubtful in preventing renal scars associated with VUR, it remains the first line treatment for high-grade reflux (grade 3-5) with an aim to prevent UTI and allow spontaneous resolution of VUR. Early identification and appropriate treatment of associated bowel bladder dysfunction is an essential part of successful medical management of VUR. Endoscopic treatment of VUR, using a bulking agent, is useful in grade 3 VUR. The main controversy regarding intervention (endoscopic/open surgical intervention) involves absence of strong evidence for these interventions in reducing renal scarring on randomized controlled trials. However, several recent trials have found the surgical interventions to be effective in reducing recurrent pyelonephritis and repeated hospital admissions.

  19. An open-label, flexible dose adaptive study evaluating the efficacy of vortioxetine in subjects with panic disorder.

    PubMed

    Shah, Anish; Northcutt, Joanne

    2018-01-01

    Despite the current treatments available for panic disorder (PD), as many as one-third of patients have persistent and treatment-resistant panic attacks. Vortioxetine is an approved medicine for major depressive disorder and has been shown to have anxiolytic properties. The purpose of this study was to evaluate its efficacy and safety in an adult population with a diagnosis of PD. The study design was open label with flexible dose strategies (5, 10, or 20 mg) with a treatment period of 10 weeks. 27 male and female subjects aged between 18 and 60 years, who met DSM-IV criteria for PD with or without agoraphobia, or who had a Panic Disorder Severity Scale (PDSS) score > 8 at baseline were enrolled. Statistical significance was established by the Student's T test. A statistically significant decrease in the occurrence of panic attacks was measured with the PDSS with vortioxetine. In addition, a moderate improvement in the quality of life and no significant side effects were observed using the Quality-of-Life Scale and Monitoring of Side Effects Scale, respectively. These results provide some support for the use of vortioxetine in the management of panic disorder. Trial registration ClinicalTrials.gov ID#: NCT02395510. Registered March 23, 2015, https://clinicaltrials.gov/ct2/show/NCT02395510.

  20. SONOlysis in prevention of Brain InfaRctions During Internal carotid Endarterectomy (SONOBIRDIE) trial - study protocol for a randomized controlled trial.

    PubMed

    Hrbáč, Tomáš; Netuka, David; Beneš, Vladimír; Nosáľ, Vladimír; Kešnerová, Petra; Tomek, Aleš; Fadrná, Táňa; Beneš, Vladimír; Fiedler, Jiří; Přibáň, Vladimír; Brozman, Miroslav; Langová, Kateřina; Herzig, Roman; Školoudík, David

    2017-01-17

    Carotid endarterectomy (CEA) is a beneficial procedure for selected patients with an internal carotid artery (ICA) stenosis. Surgical risk of CEA varies from between 2 and 15%. The aim of the study is to demonstrate the safety and effectiveness of sonolysis (continual transcranial Doppler monitoring, TCD) using a 2-MHz diagnostic probe with maximal diagnostic energy on the reduction of the incidence of stroke, transient ischemic attack (TIA) and brain infarction detected using magnetic resonance imaging (MRI) by the activation of the endogenous fibrinolytic system during CEA. Design: a multicenter, randomized, double-blind, sham-controlled trial. international, multicenter trial for patients with at least 70% symptomatic or asymptomatic ICA stenosis undergoing CEA. patients with symptomatic or asymptomatic ICA stenosis of at least 70% are candidates for CEA; a sufficient temporal bone window for TCD; aged 40-85 years, functionally independent; provision of signed informed consent. Randomization: consecutive patients will be assigned to the sonolysis or control (sham procedure) group by computer-generated 1:1 randomization. Prestudy calculations showed that a minimum of 704 patients in each group is needed to reach a significant difference with an alpha value of 0.05 (two-tailed) and a beta value of 0.8 assuming that 10% would be lost to follow-up or refuse to participate in the study (estimated 39 endpoints). the primary endpoint is the incidence of stroke or TIA during 30 days after CEA and the incidence of new ischemic lesions on brain MRI performed 24 h after CEA in the sonolysis and control groups. Secondary endpoints are occurrence of death, any stroke, or myocardial infarction within 30 days, changes in cognitive functions 1 year post procedure related to pretreatment scores, and number of new lesions and occurrence of new lesions ≥0.5 mL on post-procedural brain MRI. descriptive statistics and linear/logistic multiple regression models will be performed. Clinical relevance will be measured as relative risk reduction, absolute risk reduction and the number needed to treat. Reduction of the periprocedural complications of CEA using sonolysis as a widely available and cheap method may significantly increase the safety of CEA and extend the indication criteria for CEA. ClinicalTrials.gov, NCT02398734 . Registered on 20 March 2015.

  1. Usage and Longitudinal Effectiveness of a Web-Based Self-Help Cognitive Behavioral Therapy Program for Panic Disorder

    PubMed Central

    Denisoff, Eilenna; Selby, Peter; Bagby, R Michael; Rudy, Laura

    2005-01-01

    Background Anxiety disorders are common problems that result in enormous suffering and economic costs. The efficacy of Web-based self-help approaches for anxiety disorders has been demonstrated in a number of controlled trials. However, there is little data regarding the patterns of use and effectiveness of freely available Web-based interventions outside the context of controlled trials. Objective To examine the use and longitudinal effectiveness of a freely available, 12-session, Web-based, cognitive behavioral therapy (CBT) program for panic disorder and agoraphobia. Methods Cumulative anonymous data were analyzed from 99695 users of the Panic Center. Usage statistics for the website were examined and a longitudinal survey of self-reported symptoms for people who registered for the CBT program was conducted. The primary outcome measures were self-reported panic-attack frequency and severity at the beginning of each session (sessions 2-12). Results Between September 1, 2002 and February 1, 2004, there were 484695 visits and 1148097 page views from 99695 users to the Panic Center. In that same time period, 1161 users registered for the CBT program. There was an extremely high attrition rate with only 12 (1.03%) out of 1161 of registered users completing the 12-week program. However, even for those who remained in the program less than 12 weeks we found statistically significant reductions (P<.002) in self-reported panic attack frequency and severity, comparing 2 weeks of data against data after 3, 6, or 8 weeks. For example, the 152 users completing only 3 sessions of the program reduced their average number of attacks per day from 1.03 (week 2) to 0.63 (week 3) (P<.001). Conclusions Freely available Web-based self-help will likely be associated with high attrition. However, for the highly self-selected group who stayed in the program, significant improvements were observed. PMID:15829479

  2. Is it too early to recommend patent foramen ovale closure for all patients who suffer from migraine? A single-centre study.

    PubMed

    Chessa, Massimo; Colombo, Chiara; Butera, Gianfranco; Negura, Diana; Piazza, Luciane; Varotto, Leonardo; Bussadori, Claudio; Fesslova, Vlasta; Meola, Giovanni; Carminati, Mario

    2009-05-01

    To evaluate the course of migraine in migraine headache patients undergoing patent foramen ovale (PFO) transcatheter closure. Migraine has an important impact on the quality of life, and it seems to be one of the most disabling medical illnesses. In several studies, a high prevalence of right-to-left shunt has been described in patients with migraine, especially migraine with aura. The presence of right-to-left shunt, whatever the mechanism, may be the most potent trigger of migraine attacks in both migraine with aura and migraine without aura and the main determinant of aura in migraine with aura. A cohort of 42 patients (nine men/33 women; mean age 39 +/- 11.2 years), current migraineurs, underwent PFO percutaneous closure in our centre between January 2004 and December 2007. All patients rated the severity of their migraine preoperatively and 6 months postoperatively, indicating the frequency, duration, and intensity of the attacks and the occurrence of the aura in the prodromal phase, during the past 6 months, according to the migraine severity score. Baseline severity of migraine was higher in migraine with aura patients than in migraine without aura ones (8.8 vs. 7.5; P = 0.037). The resolution of migraine was verified in 11 patients (26%) after the closure of the PFO. A reduction in the frequency of the attacks (>=50%) was observed in 22 patients (52%). Multiple logistic regression analysis showed that the improvement in migraine with aura and migraine without aura was independent of migraine type, sex, age, cerebrovascular risk factors and cerebrovascular events, type of cardiac defect, and thrombophilic conditions. The consistent observations of this and other studies are provocative and worthy of evaluation with a prospective randomized trial using objective measures of migraine frequency and severity. However, it seems too early to recommend PFO closure for all patients who suffer from migraine until the results of ongoing large randomized trials are available.

  3. Quantum secret sharing with identity authentication based on Bell states

    NASA Astrophysics Data System (ADS)

    Abulkasim, Hussein; Hamad, Safwat; Khalifa, Amal; El Bahnasy, Khalid

    Quantum secret sharing techniques allow two parties or more to securely share a key, while the same number of parties or less can efficiently deduce the secret key. In this paper, we propose an authenticated quantum secret sharing protocol, where a quantum dialogue protocol is adopted to authenticate the identity of the parties. The participants simultaneously authenticate the identity of each other based on parts of a prior shared key. Moreover, the whole prior shared key can be reused for deducing the secret data. Although the proposed scheme does not significantly improve the efficiency performance, it is more secure compared to some existing quantum secret sharing scheme due to the identity authentication process. In addition, the proposed scheme can stand against participant attack, man-in-the-middle attack, impersonation attack, Trojan-horse attack as well as information leaks.

  4. Formal Analysis of Key Integrity in PKCS#11

    NASA Astrophysics Data System (ADS)

    Falcone, Andrea; Focardi, Riccardo

    PKCS#11 is a standard API to cryptographic devices such as smarcards, hardware security modules and usb crypto-tokens. Though widely adopted, this API has been shown to be prone to attacks in which a malicious user gains access to the sensitive keys stored in the devices. In 2008, Delaune, Kremer and Steel proposed a model to formally reason on this kind of attacks. We extend this model to also describe flaws that are based on integrity violations of the stored keys. In particular, we consider scenarios in which a malicious overwriting of keys might fool honest users into using attacker's own keys, while performing sensitive operations. We further enrich the model with a trusted key mechanism ensuring that only controlled, non-tampered keys are used in cryptographic operations, and we show how this modified API prevents the above mentioned key-replacement attacks.

  5. Development of module for neural network identification of attacks on applications and services in multi-cloud platforms

    NASA Astrophysics Data System (ADS)

    Parfenov, D. I.; Bolodurina, I. P.

    2018-05-01

    The article presents the results of developing an approach to detecting and protecting against network attacks on the corporate infrastructure deployed on the multi-cloud platform. The proposed approach is based on the combination of two technologies: a softwareconfigurable network and virtualization of network functions. The approach for searching for anomalous traffic is to use a hybrid neural network consisting of a self-organizing Kohonen network and a multilayer perceptron. The study of the work of the prototype of the system for detecting attacks, the method of forming a learning sample, and the course of experiments are described. The study showed that using the proposed approach makes it possible to increase the effectiveness of the obfuscation of various types of attacks and at the same time does not reduce the performance of the network

  6. Network information attacks on the control systems of power facilities belonging to the critical infrastructure

    NASA Astrophysics Data System (ADS)

    Loginov, E. L.; Raikov, A. N.

    2015-04-01

    The most large-scale accidents occurred as a consequence of network information attacks on the control systems of power facilities belonging to the United States' critical infrastructure are analyzed in the context of possibilities available in modern decision support systems. Trends in the development of technologies for inflicting damage to smart grids are formulated. A volume matrix of parameters characterizing attacks on facilities is constructed. A model describing the performance of a critical infrastructure's control system after an attack is developed. The recently adopted measures and legislation acts aimed at achieving more efficient protection of critical infrastructure are considered. Approaches to cognitive modeling and networked expertise of intricate situations for supporting the decision-making process, and to setting up a system of indicators for anticipatory monitoring of critical infrastructure are proposed.

  7. Application of variable-gain output feedback for high-alpha control

    NASA Technical Reports Server (NTRS)

    Ostroff, Aaron J.

    1990-01-01

    A variable-gain, optimal, discrete, output feedback design approach that is applied to a nonlinear flight regime is described. The flight regime covers a wide angle-of-attack range that includes stall and post stall. The paper includes brief descriptions of the variable-gain formulation, the discrete-control structure and flight equations used to apply the design approach, and the high performance airplane model used in the application. Both linear and nonlinear analysis are shown for a longitudinal four-model design case with angles of attack of 5, 15, 35, and 60 deg. Linear and nonlinear simulations are compared for a single-point longitudinal design at 60 deg angle of attack. Nonlinear simulations for the four-model, multi-mode, variable-gain design include a longitudinal pitch-up and pitch-down maneuver and high angle-of-attack regulation during a lateral maneuver.

  8. Patent Foramen Ovale Closure in the Setting of Cryptogenic Stroke: A Meta-Analysis of Five Randomized Trials.

    PubMed

    Garg, Lohit; Haleem, Affan; Varade, Shweta; Sivakumar, Keithan; Shah, Mahek; Patel, Brijesh; Agarwal, Manyoo; Agrawal, Sahil; Leary, Megan; Kluck, Bryan

    2018-05-24

    The clinical benefit of patent foramen ovale (PFO) closure after cryptogenic stroke has been a topic of debate for decades. Recently, 3 randomized controlled trials of PFO closure in patients with cryptogenic stroke demonstrated a significantly reduced risk of recurrent stroke compared with standard medical therapy alone. This meta-analysis was performed to clarify the efficacy of PFO closure for future stroke prevention in this population. A systematic literature search was undertaken. Published pooled data from 5 large randomized clinical trials (CLOSE, RESPECT, Gore REDUCE, CLOSURE I, and PC) were combined and then subsequently analyzed. Enrolled patients with cryptogenic stroke were assigned to receive standard medical care or to undergo endovascular PFO closure, with a primary outcome of reduction in stroke recurrence rate. Secondary outcomes included rates of transient ischemic attack (TIA), composite outcome of stroke, TIA, and death from all causes, and rates of atrial fibrillation events. We analyzed data for 3412 patients. Transcatheter PFO closure resulted in a statistically significant reduced rate of recurrent stroke, compared with medication alone. Patients undergoing closure were 58% less likely to have another stroke. The number needed to treat with PFO closure to reduce recurrent stroke for 1 patient was 40. Endovascular PFO closure was associated with a reduced risk of recurrent stroke in patients with a prior cryptogenic cerebral infarct. Although the absolute stroke reduction was small, these findings are clinically significant, given the young age of this patient population and the patients' lifetime risk of recurrent stroke. Copyright © 2018 National Stroke Association. Published by Elsevier Inc. All rights reserved.

  9. PFO and Migraine: Is There a Role for Closure?

    PubMed

    Rayhill, Melissa; Burch, Rebecca

    2017-03-01

    Observational studies suggest that closure of a patent foramen ovale for other indications may reduce or even eliminate migraine attacks, particularly migraine with aura. The first randomized clinical trial of patent foramen ovale (PFO) closure for prevention of migraine, the MIST trial, showed negative results. The results of the other two completed studies in this area have recently been published in the last year. PRIMA and PREMIUM were also both negative for their primary endpoints. The PREMIUM trial did show a reduction in headache days in the migraine with aura subgroup but the final results of this subset analysis have not been published. There may be an as yet undetermined subgroup of patients with migraine who would benefit from closure, but slow recruitment has been a barrier to further study. Several potentially life-threatening procedure-related adverse events occurred in the clinical trials. At this time, we recommend against offering PFO closure as a preventive treatment for migraine. Based on available observational data, patients for whom PFO closure is indicated for other reasons may see some improvement in their migraines.

  10. Trials of flexible pipe in sour service reveal degradation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Al-Maslamani, M.J.

    Field trials on flexible pipe offshore Qatar have shown that, under sour conditions, the layered, composite material can suffer severe degradation leading to failure. The failure demonstrates the significant effects of stress level, environmental aggressiveness, and localized hard zones in promoting sulfide stress cracking. Permeability of the sour gas through the composite layer of the flexible pipe resulted in varying degrees of sulfide attack and hydrogen embrittlement, depending on the susceptibility of the multilayered material. In the trials, the material was used as a gas-lift line in a sour-oil field in the Arabian Gulf. Flexible pipes have been used successfullymore » for transporting methanol, benzene, and gas condensates in wet sweet environments at temperatures of up to 80 C. Little or no information, however, has been available as to its corrosion resistance in sour-service wells containing 6% CO{sub 2} with 3% H{sub 2}S partial pressures and at moderate temperatures. The paper discusses an underwater survey to evaluate the damage, visual inspection, mechanical tests, metallographic exam, and trial results.« less

  11. FSM-F: Finite State Machine Based Framework for Denial of Service and Intrusion Detection in MANET

    PubMed Central

    N. Ahmed, Malik; Abdullah, Abdul Hanan; Kaiwartya, Omprakash

    2016-01-01

    Due to the continuous advancements in wireless communication in terms of quality of communication and affordability of the technology, the application area of Mobile Adhoc Networks (MANETs) significantly growing particularly in military and disaster management. Considering the sensitivity of the application areas, security in terms of detection of Denial of Service (DoS) and intrusion has become prime concern in research and development in the area. The security systems suggested in the past has state recognition problem where the system is not able to accurately identify the actual state of the network nodes due to the absence of clear definition of states of the nodes. In this context, this paper proposes a framework based on Finite State Machine (FSM) for denial of service and intrusion detection in MANETs. In particular, an Interruption Detection system for Adhoc On-demand Distance Vector (ID-AODV) protocol is presented based on finite state machine. The packet dropping and sequence number attacks are closely investigated and detection systems for both types of attacks are designed. The major functional modules of ID-AODV includes network monitoring system, finite state machine and attack detection model. Simulations are carried out in network simulator NS-2 to evaluate the performance of the proposed framework. A comparative evaluation of the performance is also performed with the state-of-the-art techniques: RIDAN and AODV. The performance evaluations attest the benefits of proposed framework in terms of providing better security for denial of service and intrusion detection attacks. PMID:27285146

  12. Antiplatelet Regimen for Patients With Breakthrough Strokes While on Aspirin: A Systematic Review and Meta-Analysis.

    PubMed

    Lee, Meng; Saver, Jeffrey L; Hong, Keun-Sik; Rao, Neal M; Wu, Yi-Ling; Ovbiagele, Bruce

    2017-09-01

    Optimal antiplatelet therapy after an ischemic stroke or transient ischemic attack while on aspirin is uncertain. We, therefore, conducted a systematic review and meta-analysis. We searched PubMed (1966 to August 2016) and bibliographies of relevant published original studies to identify randomized trials and cohort studies reporting patients who were on aspirin at the time of an index ischemic stroke or transient ischemic attack and reported hazard ratio for major adverse cardiovascular events or recurrent stroke associated with a switch to or addition of another antiplatelet agent versus maintaining aspirin monotherapy. Estimates were combined using a random effects model. Five studies with 8723 patients with ischemic stroke or transient ischemic attack were identified. Clopidogrel was used in 4 cohorts, and ticagrelor was used in 1 cohort. Pooling results showed that addition of or a switch to another antiplatelet agent, versus aspirin monotherapy, was associated with reduced risks of major adverse cardiovascular events (hazard ratio, 0.68; 95% confidence interval, 0.54-0.85) and recurrent stroke (hazard ratio, 0.70; 95% confidence interval, 0.54-0.92). Each of the strategies of addition of and switching another antiplatelet agent showed benefit versus continued aspirin monotherapy, and studies with regimen initiation in the first days after index event showed more homogenous evidence of benefit. Among patients who experience an ischemic stroke or transient ischemic attack while on aspirin monotherapy, the addition of or a switch to another antiplatelet agent, especially in the first days after index event, is associated with fewer future vascular events, including stroke. © 2017 American Heart Association, Inc.

  13. Forskolin compared with beclomethasone for prevention of asthma attacks: a single-blind clinical trial.

    PubMed

    Huerta, M; Urzúa, Z; Trujillo, X; González-Sánchez, R; Trujillo-Hernández, B

    2010-01-01

    This single-blind study compared the efficacy of oral forskolin versus inhaled beclomethasone for mild or moderately persistent adult asthma. Patients were randomly assigned to receive forskolin (one 10-mg capsule orally per day; n = 30) or beclomethasone (two 50 microg inhalations every 12 h; n = 30) for 2 months. No statistically significant improvement occurred in any lung function parameter in the forskolin-treated patients. Subjects in the beclomethasone-treated group presented a slight but statistically significant improvement in percentage forced expiratory volume in 1 s (FEV(1)), percentage forced expiratory flow in the middle (25 - 75%) expiratory phase (FEF(25 - 75%)) and percentage forced vital capacity (FVC) after 2 months of treatment, though the improvement in absolute values for FEV(1), FEF(25 - 75%), FVC and FEV(1):FVC did not reach statistical significance. There was no statistically significant difference between the forskolin and beclomethasone treatment groups for any lung function parameter at baseline or after treatment. None of the beclomethasone-treated patients had an asthma attack and one forskolin-treated patient had a mild asthma attack during the 2-month study period. More studies are needed in adult asthma patients to confirm whether forskolin may be a useful preventive treatment for mild or moderately persistent adult asthma.

  14. Management of Acute and Recurrent Gout: A Clinical Practice Guideline From the American College of Physicians.

    PubMed

    Qaseem, Amir; Harris, Russell P; Forciea, Mary Ann

    2017-01-03

    The American College of Physicians (ACP) developed this guideline to present the evidence and provide clinical recommendations on the management of gout. Using the ACP grading system, the committee based these recommendations on a systematic review of randomized, controlled trials; systematic reviews; and large observational studies published between January 2010 and March 2016. Clinical outcomes evaluated included pain, joint swelling and tenderness, activities of daily living, patient global assessment, recurrence, intermediate outcomes of serum urate levels, and harms. The target audience for this guideline includes all clinicians, and the target patient population includes adults with acute or recurrent gout. ACP recommends that clinicians choose corticosteroids, nonsteroidal anti-inflammatory drugs (NSAIDs), or colchicine to treat patients with acute gout. (Grade: strong recommendation, high-quality evidence). ACP recommends that clinicians use low-dose colchicine when using colchicine to treat acute gout. (Grade: strong recommendation, moderate-quality evidence). ACP recommends against initiating long-term urate-lowering therapy in most patients after a first gout attack or in patients with infrequent attacks. (Grade: strong recommendation, moderate-quality evidence). ACP recommends that clinicians discuss benefits, harms, costs, and individual preferences with patients before initiating urate-lowering therapy, including concomitant prophylaxis, in patients with recurrent gout attacks. (Grade: strong recommendation, moderate-quality evidence).

  15. Evolutionary Responses to Invasion: Cane Toad Sympatric Fish Show Enhanced Avoidance Learning

    PubMed Central

    Caller, Georgina; Brown, Culum

    2013-01-01

    The introduced cane toad (Bufo marinus) poses a major threat to biodiversity due to its lifelong toxicity. Several terrestrial native Australian vertebrates are adapting to the cane toad’s presence and lab trials have demonstrated that repeated exposure to B. marinus can result in learnt avoidance behaviour. Here we investigated whether aversion learning is occurring in aquatic ecosystems by comparing cane toad naïve and sympatric populations of crimson spotted rainbow fish (Melanotaenia duboulayi). The first experiment indicated that fish from the sympatric population had pre-existing aversion to attacking cane toad tadpoles but also showed reduced attacks on native tadpoles. The second experiment revealed that fish from both naïve and sympatric populations learned to avoid cane toad tadpoles following repeated, direct exposure. Allopatric fish also developed a general aversion to tadpoles. The aversion learning abilities of both groups was examined using an experiment involving novel distasteful prey items. While both populations developed a general avoidance of edible pellets in the presence of distasteful pellets, only the sympatric population significantly reduced the number of attacks on the novel distasteful prey item. These results indicate that experience with toxic prey items over multiple generations can enhance avoidance leaning capabilities via natural selection. PMID:23372788

  16. Soluble CD40L Is a Useful Marker to Predict Future Strokes in Patients With Minor Stroke and Transient Ischemic Attack.

    PubMed

    Li, Jiejie; Wang, Yilong; Lin, Jinxi; Wang, David; Wang, Anxin; Zhao, Xingquan; Liu, Liping; Wang, Chunxue; Wang, Yongjun

    2015-07-01

    Elevated soluble CD40 ligand (sCD40L) was shown to be related to cardiovascular events, but the role of sCD40L in predicting recurrent stroke remains unclear. Baseline sCD40L levels were measured in 3044 consecutive patients with acute minor stroke and transient ischemic attack, who had previously been enrolled in the Clopidogrel in High-Risk Patients With Acute Nondisabling Cerebrovascular Events (CHANCE) trial. Cox proportional-hazards model was used to assess the association of sCD40L with recurrent stroke. Patients in the top tertile of sCD40L levels had increased risk of recurrent stroke comparing with those in the bottom tertile, after adjusted for conventional confounding factors (hazard ratio, 1.49; 95% confidence interval, 1.11-2.00; P=0.008). The patients with elevated levels of both sCD40L and high-sensitive C-reactive protein also had increased risk of recurrent stroke (hazard ratio, 1.81; 95% confidence interval, 1.23-2.68; P=0.003). Elevated sCD40L levels independently predict recurrent stroke in patients with minor stroke and transient ischemic attack. URL: http://www.clinicaltrials.gov. Unique identifier: NCT00979589. © 2015 American Heart Association, Inc.

  17. Triggers of acute attacks of gout, does age of gout onset matter? A primary care based cross-sectional study.

    PubMed

    Abhishek, Abhishek; Valdes, Ana M; Jenkins, Wendy; Zhang, Weiya; Doherty, Michael

    2017-01-01

    To determine the proportion of people with gout who self-report triggers of acute attacks; identify the commonly reported triggers, and examine the disease and demographic features associated with self-reporting any trigger(s) of acute attacks of gout. Individuals with gout were asked to fill a questionnaire enquiring about triggers that precipitated their acute gout attacks. Binary logistic regression was used to compute odds ratio (OR) and 95% confidence intervals (CI) to examine the association between having ≥1 self-reported trigger of acute gout and disease and demographic risk factors and to adjust for covariates. All statistical analyses were performed using STATA. 550 participants returned completed questionnaires. 206 (37.5%) reported at least one trigger of acute attacks, and less than 5% reported >2 triggers. Only 28.73% participants reported that their most recent gout attack was triggered by dietary or lifestyle risk factors. The most frequently self-reported triggers were alcohol intake (14.18%), red-meat or sea-food consumption (6%), dehydration (4.91%), injury or excess activity (4.91%), and excessively warm or cold weather (4.36% and 5.45%). Patients who had onset of gout before the age of 50 years were significantly more likely to identify a trigger for precipitating their acute gout attacks (aOR (95%CI) 1.73 (1.12-2.68) after adjusting for covariates. Most people with gout do not identify any triggers for acute attacks, and identifiable triggers are more common in those with young onset gout. Less than 20% people self-reported acute gout attacks from conventionally accepted triggers of gout e.g. alcohol, red-meat intake, while c.5% reported novel triggers such as dehydration, injury or physical activity, and weather extremes.

  18. Clinical features of 27 shark attack cases on La Réunion Island.

    PubMed

    Ballas, Richard; Saetta, Ghislain; Peuchot, Charline; Elkienbaum, Philippe; Poinsot, Emmanuelle

    2017-05-01

    Between January 2000 and September 2016, there have been 27 documented shark attacks on La Réunion Island. The insular nature of La Réunion has allowed us to perform an extensive survey of these attacks. The objective was to describe the clinical features of these shark attacks, as only case reports have been published up to now. This was a retrospective observational study of the 27 cases of nonprovoked shark attacks that have occurred between January 2000 and September 2016. Post-humate predation, provoked attacks, and isolated attack on devices were excluded. All bone and vascular injuries were documented in the 21 remaining cases. Prehospital tourniquet use was specifically recorded. Among the 21 victims, eight died (38%) despite rapid use of resuscitation techniques in five cases when it was feasible; these techniques were not needed in the survivors. Thirteen patients were immediately treated in the operating room. Amputation or disarticulation occurred 13 times in 10 victims, five of whom died. Twelve injuries to major vascular structures were found in 11 victims, six of which died. A prehospital tourniquet was applied in four of the five surviving victims who had injuries to major vascular structures (including one victim with major humeral and femoral artery damage) and in one victim who died (the very proximal wound was not controlled). Our study found that quickly applying a tourniquet to the injured limb(s) contributes to the victim's survival. Disarticulation is a particular feature of shark attacks. The number and severity of shark attacks at La Réunion Island are worse than in the rest of the world. Epidemiological, level V.

  19. Triggers of acute attacks of gout, does age of gout onset matter? A primary care based cross-sectional study

    PubMed Central

    Valdes, Ana M.; Jenkins, Wendy; Zhang, Weiya; Doherty, Michael

    2017-01-01

    Objectives To determine the proportion of people with gout who self-report triggers of acute attacks; identify the commonly reported triggers, and examine the disease and demographic features associated with self-reporting any trigger(s) of acute attacks of gout. Methods Individuals with gout were asked to fill a questionnaire enquiring about triggers that precipitated their acute gout attacks. Binary logistic regression was used to compute odds ratio (OR) and 95% confidence intervals (CI) to examine the association between having ≥1 self-reported trigger of acute gout and disease and demographic risk factors and to adjust for covariates. All statistical analyses were performed using STATA. Results 550 participants returned completed questionnaires. 206 (37.5%) reported at least one trigger of acute attacks, and less than 5% reported >2 triggers. Only 28.73% participants reported that their most recent gout attack was triggered by dietary or lifestyle risk factors. The most frequently self-reported triggers were alcohol intake (14.18%), red-meat or sea-food consumption (6%), dehydration (4.91%), injury or excess activity (4.91%), and excessively warm or cold weather (4.36% and 5.45%). Patients who had onset of gout before the age of 50 years were significantly more likely to identify a trigger for precipitating their acute gout attacks (aOR (95%CI) 1.73 (1.12–2.68) after adjusting for covariates. Conclusion Most people with gout do not identify any triggers for acute attacks, and identifiable triggers are more common in those with young onset gout. Less than 20% people self-reported acute gout attacks from conventionally accepted triggers of gout e.g. alcohol, red-meat intake, while c.5% reported novel triggers such as dehydration, injury or physical activity, and weather extremes. PMID:29023487

  20. Blood transfusion for preventing primary and secondary stroke in people with sickle cell disease.

    PubMed

    Estcourt, Lise J; Fortin, Patricia M; Hopewell, Sally; Trivella, Marialena; Wang, Winfred C

    2017-01-17

    Sickle cell disease is one of the commonest severe monogenic disorders in the world, due to the inheritance of two abnormal haemoglobin (beta globin) genes. Sickle cell disease can cause severe pain, significant end-organ damage, pulmonary complications, and premature death. Stroke affects around 10% of children with sickle cell anaemia (HbSS). Chronic blood transfusions may reduce the risk of vaso-occlusion and stroke by diluting the proportion of sickled cells in the circulation.This is an update of a Cochrane Review first published in 2002, and last updated in 2013. To assess risks and benefits of chronic blood transfusion regimens in people with sickle cell disease for primary and secondary stroke prevention (excluding silent cerebral infarcts). We searched for relevant trials in the Cochrane Library, MEDLINE (from 1946), Embase (from 1974), the Transfusion Evidence Library (from 1980), and ongoing trial databases; all searches current to 04 April 2016.We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Haemoglobinopathies Trials Register: 25 April 2016. Randomised controlled trials comparing red blood cell transfusions as prophylaxis for stroke in people with sickle cell disease to alternative or standard treatment. There were no restrictions by outcomes examined, language or publication status. Two authors independently assessed trial eligibility and the risk of bias and extracted data. We included five trials (660 participants) published between 1998 and 2016. Four of these trials were terminated early. The vast majority of participants had the haemoglobin (Hb)SS form of sickle cell disease.Three trials compared regular red cell transfusions to standard care in primary prevention of stroke: two in children with no previous long-term transfusions; and one in children and adolescents on long-term transfusion.Two trials compared the drug hydroxyurea (hydroxycarbamide) and phlebotomy to long-term transfusions and iron chelation therapy: one in primary prevention (children); and one in secondary prevention (children and adolescents).The quality of the evidence was very low to moderate across different outcomes according to GRADE methodology. This was due to the trials being at a high risk of bias due to lack of blinding, indirectness and imprecise outcome estimates. Red cell transfusions versus standard care Children with no previous long-term transfusionsLong-term transfusions probably reduce the incidence of clinical stroke in children with a higher risk of stroke (abnormal transcranial doppler velocities or previous history of silent cerebral infarct), risk ratio 0.12 (95% confidence interval 0.03 to 0.49) (two trials, 326 participants), moderate quality evidence.Long-term transfusions may: reduce the incidence of other sickle cell disease-related complications (acute chest syndrome, risk ratio 0.24 (95% confidence interval 0.12 to 0.48)) (two trials, 326 participants); increase quality of life (difference estimate -0.54, 95% confidence interval -0.92 to -0.17) (one trial, 166 participants); but make little or no difference to IQ scores (least square mean: 1.7, standard error 95% confidence interval -1.1 to 4.4) (one trial, 166 participants), low quality evidence.We are very uncertain whether long-term transfusions: reduce the risk of transient ischaemic attacks, Peto odds ratio 0.13 (95% confidence interval 0.01 to 2.11) (two trials, 323 participants); have any effect on all-cause mortality, no deaths reported (two trials, 326 participants); or increase the risk of alloimmunisation, risk ratio 3.16 (95% confidence interval 0.18 to 57.17) (one trial, 121 participants), very low quality evidence. Children and adolescents with previous long-term transfusions (one trial, 79 participants)We are very uncertain whether continuing long-term transfusions reduces the incidence of: stroke, risk ratio 0.22 (95% confidence interval 0.01 to 4.35); or all-cause mortality, Peto odds ratio 8.00 (95% confidence interval 0.16 to 404.12), very low quality evidence.Several review outcomes were only reported in one trial arm (sickle cell disease-related complications, alloimmunisation, transient ischaemic attacks).The trial did not report neurological impairment, or quality of life. Hydroxyurea and phlebotomy versus red cell transfusions and chelationNeither trial reported on neurological impairment, alloimmunisation, or quality of life. Primary prevention, children (one trial, 121 participants)Switching to hydroxyurea and phlebotomy may have little or no effect on liver iron concentrations, mean difference -1.80 mg Fe/g dry-weight liver (95% confidence interval -5.16 to 1.56), low quality evidence.We are very uncertain whether switching to hydroxyurea and phlebotomy has any effect on: risk of stroke (no strokes); all-cause mortality (no deaths); transient ischaemic attacks, risk ratio 1.02 (95% confidence interval 0.21 to 4.84); or other sickle cell disease-related complications (acute chest syndrome, risk ratio 2.03 (95% confidence interval 0.39 to 10.69)), very low quality evidence. Secondary prevention, children and adolescents (one trial, 133 participants)Switching to hydroxyurea and phlebotomy may: increase the risk of sickle cell disease-related serious adverse events, risk ratio 3.10 (95% confidence interval 1.42 to 6.75); but have little or no effect on median liver iron concentrations (hydroxyurea, 17.3 mg Fe/g dry-weight liver (interquartile range 10.0 to 30.6)); transfusion 17.3 mg Fe/g dry-weight liver (interquartile range 8.8 to 30.7), low quality evidence.We are very uncertain whether switching to hydroxyurea and phlebotomy: increases the risk of stroke, risk ratio 14.78 (95% confidence interval 0.86 to 253.66); or has any effect on all-cause mortality, Peto odds ratio 0.98 (95% confidence interval 0.06 to 15.92); or transient ischaemic attacks, risk ratio 0.66 (95% confidence interval 0.25 to 1.74), very low quality evidence. There is no evidence for managing adults, or children who do not have HbSS sickle cell disease.In children who are at higher risk of stroke and have not had previous long-term transfusions, there is moderate quality evidence that long-term red cell transfusions reduce the risk of stroke, and low quality evidence they also reduce the risk of other sickle cell disease-related complications.In primary and secondary prevention of stroke there is low quality evidence that switching to hydroxyurea with phlebotomy has little or no effect on the liver iron concentration.In secondary prevention of stroke there is low-quality evidence that switching to hydroxyurea with phlebotomy increases the risk of sickle cell disease-related events.All other evidence in this review is of very low quality.

  1. Blood transfusion for preventing primary and secondary stroke in people with sickle cell disease

    PubMed Central

    Estcourt, Lise J; Fortin, Patricia M; Hopewell, Sally; Trivella, Marialena; Wang, Winfred C

    2017-01-01

    Background Sickle cell disease is one of the commonest severe monogenic disorders in the world, due to the inheritance of two abnormal haemoglobin (beta globin) genes. Sickle cell disease can cause severe pain, significant end-organ damage, pulmonary complications, and premature death. Stroke affects around 10% of children with sickle cell anaemia (HbSS). Chronic blood transfusions may reduce the risk of vaso-occlusion and stroke by diluting the proportion of sickled cells in the circulation. This is an update of a Cochrane Review first published in 2002, and last updated in 2013. Objectives To assess risks and benefits of chronic blood transfusion regimens in people with sickle cell disease for primary and secondary stroke prevention (excluding silent cerebral infarcts). Search methods We searched for relevant trials in the Cochrane Library, MEDLINE (from 1946), Embase (from 1974), the Transfusion Evidence Library (from 1980), and ongoing trial databases; all searches current to 04 April 2016. We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Haemoglobinopathies Trials Register: 25 April 2016. Selection criteria Randomised controlled trials comparing red blood cell transfusions as prophylaxis for stroke in people with sickle cell disease to alternative or standard treatment. There were no restrictions by outcomes examined, language or publication status. Data collection and analysis Two authors independently assessed trial eligibility and the risk of bias and extracted data. Main results We included five trials (660 participants) published between 1998 and 2016. Four of these trials were terminated early. The vast majority of participants had the haemoglobin (Hb)SS form of sickle cell disease. Three trials compared regular red cell transfusions to standard care in primary prevention of stroke: two in children with no previous long-term transfusions; and one in children and adolescents on long-term transfusion. Two trials compared the drug hydroxyurea (hydroxycarbamide) and phlebotomy to long-term transfusions and iron chelation therapy: one in primary prevention (children); and one in secondary prevention (children and adolescents). The quality of the evidence was very low to moderate across different outcomes according to GRADE methodology. This was due to the trials being at a high risk of bias due to lack of blinding, indirectness and imprecise outcome estimates. Red cell transfusions versus standard care Children with no previous long-term transfusions Long-term transfusions probably reduce the incidence of clinical stroke in children with a higher risk of stroke (abnormal transcranial doppler velocities or previous history of silent cerebral infarct), risk ratio 0.12 (95% confidence interval 0.03 to 0.49) (two trials, 326 participants), moderate quality evidence. Long-term transfusions may: reduce the incidence of other sickle cell disease-related complications (acute chest syndrome, risk ratio 0.24 (95% confidence interval 0.12 to 0.48)) (two trials, 326 participants); increase quality of life (difference estimate -0.54, 95% confidence interval -0.92 to -0.17) (one trial, 166 participants); but make little or no difference to IQ scores (least square mean: 1.7, standard error 95% confidence interval -1.1 to 4.4) (one trial, 166 participants), low quality evidence. We are very uncertain whether long-term transfusions: reduce the risk of transient ischaemic attacks, Peto odds ratio 0.13 (95% confidence interval 0.01 to 2.11) (two trials, 323 participants); have any effect on all-cause mortality, no deaths reported (two trials, 326 participants); or increase the risk of alloimmunisation, risk ratio 3.16 (95% confidence interval 0.18 to 57.17) (one trial, 121 participants), very low quality evidence. Children and adolescents with previous long-term transfusions (one trial, 79 participants) We are very uncertain whether continuing long-term transfusions reduces the incidence of: stroke, risk ratio 0.22 (95% confidence interval 0.01 to 4.35); or all-cause mortality, Peto odds ratio 8.00 (95% confidence interval 0.16 to 404.12), very low quality evidence. Several review outcomes were only reported in one trial arm (sickle cell disease-related complications, alloimmunisation, transient ischaemic attacks). The trial did not report neurological impairment, or quality of life. Hydroxyurea and phlebotomy versus red cell transfusions and chelation Neither trial reported on neurological impairment, alloimmunisation, or quality of life. Primary prevention, children (one trial, 121 participants) Switching to hydroxyurea and phlebotomy may have little or no effect on liver iron concentrations, mean difference -1.80 mg Fe/g dry-weight liver (95% confidence interval -5.16 to 1.56), low quality evidence. We are very uncertain whether switching to hydroxyurea and phlebotomy has any effect on: risk of stroke (no strokes); all-cause mortality (no deaths); transient ischaemic attacks, risk ratio 1.02 (95% confidence interval 0.21 to 4.84); or other sickle cell disease-related complications (acute chest syndrome, risk ratio 2.03 (95% confidence interval 0.39 to 10.69)), very low quality evidence. Secondary prevention, children and adolescents (one trial, 133 participants) Switching to hydroxyurea and phlebotomy may: increase the risk of sickle cell disease-related serious adverse events, risk ratio 3.10 (95% confidence interval 1.42 to 6.75); but have little or no effect on median liver iron concentrations (hydroxyurea, 17.3 mg Fe/g dry-weight liver (interquartile range 10.0 to 30.6)); transfusion 17.3 mg Fe/g dry-weight liver (interquartile range 8.8 to 30.7), low quality evidence. We are very uncertain whether switching to hydroxyurea and phlebotomy: increases the risk of stroke, risk ratio 14.78 (95% confidence interval 0.86 to 253.66); or has any effect on all-cause mortality, Peto odds ratio 0.98 (95% confidence interval 0.06 to 15.92); or transient ischaemic attacks, risk ratio 0.66 (95% confidence interval 0.25 to 1.74), very low quality evidence. Authors’ conclusions There is no evidence for managing adults, or children who do not have HbSS sickle cell disease. In children who are at higher risk of stroke and have not had previous long-term transfusions, there is moderate quality evidence that long-term red cell transfusions reduce the risk of stroke, and low quality evidence they also reduce the risk of other sickle cell disease-related complications. In primary and secondary prevention of stroke there is low quality evidence that switching to hydroxyurea with phlebotomy has little or no effect on the liver iron concentration. In secondary prevention of stroke there is low-quality evidence that switching to hydroxyurea with phlebotomy increases the risk of sickle cell disease-related events. All other evidence in this review is of very low quality. PMID:24226646

  2. A Security Assessment Mechanism for Software-Defined Networking-Based Mobile Networks.

    PubMed

    Luo, Shibo; Dong, Mianxiong; Ota, Kaoru; Wu, Jun; Li, Jianhua

    2015-12-17

    Software-Defined Networking-based Mobile Networks (SDN-MNs) are considered the future of 5G mobile network architecture. With the evolving cyber-attack threat, security assessments need to be performed in the network management. Due to the distinctive features of SDN-MNs, such as their dynamic nature and complexity, traditional network security assessment methodologies cannot be applied directly to SDN-MNs, and a novel security assessment methodology is needed. In this paper, an effective security assessment mechanism based on attack graphs and an Analytic Hierarchy Process (AHP) is proposed for SDN-MNs. Firstly, this paper discusses the security assessment problem of SDN-MNs and proposes a methodology using attack graphs and AHP. Secondly, to address the diversity and complexity of SDN-MNs, a novel attack graph definition and attack graph generation algorithm are proposed. In order to quantify security levels, the Node Minimal Effort (NME) is defined to quantify attack cost and derive system security levels based on NME. Thirdly, to calculate the NME of an attack graph that takes the dynamic factors of SDN-MN into consideration, we use AHP integrated with the Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS) as the methodology. Finally, we offer a case study to validate the proposed methodology. The case study and evaluation show the advantages of the proposed security assessment mechanism.

  3. A Security Assessment Mechanism for Software-Defined Networking-Based Mobile Networks

    PubMed Central

    Luo, Shibo; Dong, Mianxiong; Ota, Kaoru; Wu, Jun; Li, Jianhua

    2015-01-01

    Software-Defined Networking-based Mobile Networks (SDN-MNs) are considered the future of 5G mobile network architecture. With the evolving cyber-attack threat, security assessments need to be performed in the network management. Due to the distinctive features of SDN-MNs, such as their dynamic nature and complexity, traditional network security assessment methodologies cannot be applied directly to SDN-MNs, and a novel security assessment methodology is needed. In this paper, an effective security assessment mechanism based on attack graphs and an Analytic Hierarchy Process (AHP) is proposed for SDN-MNs. Firstly, this paper discusses the security assessment problem of SDN-MNs and proposes a methodology using attack graphs and AHP. Secondly, to address the diversity and complexity of SDN-MNs, a novel attack graph definition and attack graph generation algorithm are proposed. In order to quantify security levels, the Node Minimal Effort (NME) is defined to quantify attack cost and derive system security levels based on NME. Thirdly, to calculate the NME of an attack graph that takes the dynamic factors of SDN-MN into consideration, we use AHP integrated with the Technique for Order Preference by Similarity to an Ideal Solution (TOPSIS) as the methodology. Finally, we offer a case study to validate the proposed methodology. The case study and evaluation show the advantages of the proposed security assessment mechanism. PMID:26694409

  4. Detecting unknown attacks in wireless sensor networks that contain mobile nodes.

    PubMed

    Banković, Zorana; Fraga, David; Moya, José M; Vallejo, Juan Carlos

    2012-01-01

    As wireless sensor networks are usually deployed in unattended areas, security policies cannot be updated in a timely fashion upon identification of new attacks. This gives enough time for attackers to cause significant damage. Thus, it is of great importance to provide protection from unknown attacks. However, existing solutions are mostly concentrated on known attacks. On the other hand, mobility can make the sensor network more resilient to failures, reactive to events, and able to support disparate missions with a common set of sensors, yet the problem of security becomes more complicated. In order to address the issue of security in networks with mobile nodes, we propose a machine learning solution for anomaly detection along with the feature extraction process that tries to detect temporal and spatial inconsistencies in the sequences of sensed values and the routing paths used to forward these values to the base station. We also propose a special way to treat mobile nodes, which is the main novelty of this work. The data produced in the presence of an attacker are treated as outliers, and detected using clustering techniques. These techniques are further coupled with a reputation system, in this way isolating compromised nodes in timely fashion. The proposal exhibits good performances at detecting and confining previously unseen attacks, including the cases when mobile nodes are compromised.

  5. TauG-guidance of transients in expressive musical performance.

    PubMed

    Schogler, Benjaman; Pepping, Gert-Jan; Lee, David N

    2008-08-01

    The sounds in expressive musical performance, and the movements that produce them, offer insight into temporal patterns in the brain that generate expression. To gain understanding of these brain patterns, we analyzed two types of transient sounds, and the movements that produced them, during a vocal duet and a bass solo. The transient sounds studied were inter-tone f (0)(t)-glides (the continuous change in fundamental frequency, f (0)(t), when gliding from one tone to the next), and attack intensity-glides (the continuous rise in sound intensity when attacking, or initiating, a tone). The temporal patterns of the inter-tone f (0)(t)-glides and attack intensity-glides, and of the movements producing them, all conformed to the mathematical function, tau (G)(t) (called tauG), predicted by General Tau Theory, and assumed to be generated in the brain. The values of the parameters of the tau (G)(t) function were modulated by the performers when they modulated musical expression. Thus the tau (G)(t) function appears to be a fundamental of brain activity entailed in the generation of expressive temporal patterns of movement and sound.

  6. Efficient and anonymous two-factor user authentication in wireless sensor networks: achieving user anonymity with lightweight sensor computation.

    PubMed

    Nam, Junghyun; Choo, Kim-Kwang Raymond; Han, Sangchul; Kim, Moonseong; Paik, Juryon; Won, Dongho

    2015-01-01

    A smart-card-based user authentication scheme for wireless sensor networks (hereafter referred to as a SCA-WSN scheme) is designed to ensure that only users who possess both a smart card and the corresponding password are allowed to gain access to sensor data and their transmissions. Despite many research efforts in recent years, it remains a challenging task to design an efficient SCA-WSN scheme that achieves user anonymity. The majority of published SCA-WSN schemes use only lightweight cryptographic techniques (rather than public-key cryptographic techniques) for the sake of efficiency, and have been demonstrated to suffer from the inability to provide user anonymity. Some schemes employ elliptic curve cryptography for better security but require sensors with strict resource constraints to perform computationally expensive scalar-point multiplications; despite the increased computational requirements, these schemes do not provide user anonymity. In this paper, we present a new SCA-WSN scheme that not only achieves user anonymity but also is efficient in terms of the computation loads for sensors. Our scheme employs elliptic curve cryptography but restricts its use only to anonymous user-to-gateway authentication, thereby allowing sensors to perform only lightweight cryptographic operations. Our scheme also enjoys provable security in a formal model extended from the widely accepted Bellare-Pointcheval-Rogaway (2000) model to capture the user anonymity property and various SCA-WSN specific attacks (e.g., stolen smart card attacks, node capture attacks, privileged insider attacks, and stolen verifier attacks).

  7. Efficient and Anonymous Two-Factor User Authentication in Wireless Sensor Networks: Achieving User Anonymity with Lightweight Sensor Computation

    PubMed Central

    Nam, Junghyun; Choo, Kim-Kwang Raymond; Han, Sangchul; Kim, Moonseong; Paik, Juryon; Won, Dongho

    2015-01-01

    A smart-card-based user authentication scheme for wireless sensor networks (hereafter referred to as a SCA-WSN scheme) is designed to ensure that only users who possess both a smart card and the corresponding password are allowed to gain access to sensor data and their transmissions. Despite many research efforts in recent years, it remains a challenging task to design an efficient SCA-WSN scheme that achieves user anonymity. The majority of published SCA-WSN schemes use only lightweight cryptographic techniques (rather than public-key cryptographic techniques) for the sake of efficiency, and have been demonstrated to suffer from the inability to provide user anonymity. Some schemes employ elliptic curve cryptography for better security but require sensors with strict resource constraints to perform computationally expensive scalar-point multiplications; despite the increased computational requirements, these schemes do not provide user anonymity. In this paper, we present a new SCA-WSN scheme that not only achieves user anonymity but also is efficient in terms of the computation loads for sensors. Our scheme employs elliptic curve cryptography but restricts its use only to anonymous user-to-gateway authentication, thereby allowing sensors to perform only lightweight cryptographic operations. Our scheme also enjoys provable security in a formal model extended from the widely accepted Bellare-Pointcheval-Rogaway (2000) model to capture the user anonymity property and various SCA-WSN specific attacks (e.g., stolen smart card attacks, node capture attacks, privileged insider attacks, and stolen verifier attacks). PMID:25849359

  8. Imperfect chemical female mimicry in males of the ant Cardiocondyla obscurior

    NASA Astrophysics Data System (ADS)

    Cremer, Sylvia; D'Ettorre, Patrizia; Drijfhout, Falko P.; Sledge, Matthew F.; Turillazzi, Stefano; Heinze, Jürgen

    2008-11-01

    Winged and wingless males coexist in the ant Cardiocondyla obscurior. Wingless (“ergatoid”) males never leave their maternal colony and fight remorselessly among each other for the access to emerging females. The peaceful winged males disperse after about 10 days, but beforehand also mate in the nest. In the first 5 days of their life, winged males perform a chemical female mimicry that protects them against attack and even makes them sexually attractive to ergatoid males. When older, the chemical profile of winged males no longer matches that of virgin females; nevertheless, they are still tolerated, which so far has been puzzling. Contrasting this general pattern, we have identified a single aberrant colony in which all winged males were attacked and killed by the ergatoid males. A comparative analysis of the morphology and chemical profile of these untypical attacked winged males and the tolerated males from several normal colonies revealed that normal old males are still performing some chemical mimicry to the virgin queens, though less perfect than in their young ages. The anomalous attacked winged males, on the other hand, had a very different odour to the females. Our study thus exemplifies that the analysis of rare malfunctioning can add valuable insight on functioning under normal conditions and allows the conclusion that older winged males from normal colonies of the ant C. obscurior are guarded through an imperfect chemical female mimicry, still close enough to protect against attacks by the wingless fighters yet dissimilar enough not to elicit their sexual interest.

  9. Dipyridamole for preventing recurrent ischemic stroke and other vascular events: a meta-analysis of individual patient data from randomized controlled trials.

    PubMed

    Leonardi-Bee, Jo; Bath, Philip M W; Bousser, Marie-Germaine; Davalos, Antoni; Diener, Hans-Christoph; Guiraud-Chaumeil, Bernard; Sivenius, Juhani; Yatsu, Frank; Dewey, Michael E

    2005-01-01

    Results from randomized controlled trials of dipyridamole, given with or without aspirin, for secondary prevention after ischemic stroke or transient ischemic attack (TIA) have given conflicting results. We performed a meta-analysis using individual patient data from relevant randomized controlled trials. Randomized controlled trials involving dipyridamole in patients with previous ischemic stroke or TIA were sought from searches of the Cochrane Library, other electronic databases, references lists, earlier reviews, and contact with the manufacturer of dipyridamole. Individual patient data were merged from 5 of 7 relevant trials involving 11 459 patients. Results were adjusted for age, gender, qualifying event, and history of previous hypertension. Recurrent stroke was reduced by dipyridamole as compared with control (OR, 0.82; 95% CI, 0.68 to 1.00), and by combined aspirin and dipyridamole versus aspirin alone (OR, 0.78; 95% CI, 0.65 to 0.93), dipyridamole alone (OR, 0.74; 95% CI, 0.60 to 0.90), or control (OR, 0.61; 95% CI, 0.51 to 0.71). The point estimates obtained for the comparisons of aspirin and dipyridamole versus control (OR, 0.63; significant) or versus aspirin (OR, 0.88; nonsignificant) were similar if the data from the largest trial, ESPS II (which provided 57% of data), were excluded. Similar findings were observed for nonfatal stroke. The combination of aspirin and dipyridamole also significantly reduced the composite outcome of nonfatal stroke, nonfatal myocardial infarction, and vascular death as compared with aspirin alone (OR, 0.84; 95% CI, 0.72 to 0.97), dipyridamole alone (OR, 0.76; 95% CI, 0.64 to 0.90), or control (OR, 0.66; 95% CI, 0.57 to 0.75). Vascular death was not altered in any group. Dipyridamole, given alone or with aspirin, reduces stroke recurrence in patients with previous ischemic cerebrovascular disease. The combination of aspirin and dipyridamole also reduces the composite of nonfatal stroke, nonfatal myocardial infarction, and vascular death as compared with aspirin alone.

  10. Long-term follow-up of moderately hypercholesterolemic hypertensive patients following randomization to pravastatin vs. usual care: the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT-LLT)

    PubMed Central

    Margolis, Karen L.; Davis, Barry R.; Baimbridge, Charles; Ciocon, Jerry O.; Cuyjet, Aloysius B.; Dart, Richard A.; Einhorn, Paula T.; Ford, Charles E.; Gordon, David; Hartney, Thomas J; Haywood, L. Julian; Holtzman, Jordan; Mathis, David E.; Oparil, Suzanne; Probstfield, Jeffrey L.; Simpson, Lara M.; Stokes, John D.; Wiegmann, Thomas B.; Williamson, Jeff D.

    2015-01-01

    A randomized, controlled, multicenter trial assigned well-controlled hypertensive participants ≥55 years, with moderate hypercholesterolemia to receive pravastatin (n=5170) or usual care (n=5185) for 4-8 years, when trial therapy was discontinued. Passive surveillance using national databases to ascertain deaths and hospitalizations continued for total follow-up of 8-13 years to assess whether mortality and morbidity differences persisted or new differences developed. During the post-trial period, fatal and nonfatal outcomes were available for 98% and 64% of participants, respectively. Primary outcome was all-cause mortality; secondary outcomes included cardiovascular mortality, coronary heart disease (CHD), stroke, heart failure, cardiovascular disease, and end-stage renal disease. No significant differences appeared in mortality for pravastatin versus usual care (hazard ratio [HR], 0.96; 95% confidence interval [CI], 0.89-1.03), or other secondary outcomes. Similar to the previously reported in-trial result, there was a significant treatment effect for CHD in Blacks (HR, 0.79; 95% CI, 0.64-0.98). However, the in-trial result showing a significant treatment by race effect did not remain significant over the entire follow-up (P=.08). These findings are consistent with evidence from other large trials that show statins prevent CHD and add evidence that they are effective for CHD prevention in Blacks. PMID:23889716

  11. Increase in the maximum lift of an airplane wing due to a sudden increase in its effective angle of attack resulting from a gust

    NASA Technical Reports Server (NTRS)

    Kramer, Max

    1932-01-01

    Wind-tunnel tests are described, in which the angle of attack of a wing model was suddenly increased (producing the effect of a vertical gust) and the resulting forces were measured. It was found that the maximum lift coefficient increases in proportion to the rate of increase in the angle of attack. This fact is important for the determination of the gust stresses of airplanes with low wing loading. The results of the calculation of the corrective factor are given for a high-performance glider and a light sport plane of conventional type.

  12. Study of aerodynamic technology for VSTOL fighter attack aircraft

    NASA Technical Reports Server (NTRS)

    Burhans, W., Jr.; Crafta, V. J., Jr.; Dannenhoffer, N.; Dellamura, F. A.; Krepski, R. E.

    1978-01-01

    Vertical short takeoff aircraft capability, supersonic dash capability, and transonic agility were investigated for the development of Fighter/attack aircraft to be accommodated on ships smaller than present aircraft carriers. Topics covered include: (1) description of viable V/STOL fighter/attack configuration (a high wing, close-coupled canard, twin-engine, control configured aircraft) which meets or exceeds specified levels of vehicle performance; (2) estimates of vehicle aerodynamic characteristics and the methodology utilized to generate them; (3) description of propulsion system characteristics and vehicle mass properties; (4) identification of areas of aerodynamic uncertainty; and (5) a test program to investigate the areas of aerodynamic uncertainty in the conventional flight mode.

  13. Contemporary medical therapies of atherosclerotic carotid artery disease.

    PubMed

    Cheng, Suk F; Brown, Martin M

    2017-03-01

    Contemporary medical therapy consists of identification and treatment of all patient-modifiable vascular risk factors. Specific atherosclerotic disease therapies are designed to reduce the risk of thrombosis, and the disease progression in order to reduce the risk of future cardiovascular events. Contemporary medical management emphasizes the need to support the patient in achieving lifestyle modifications and to adjust medication to achieve individualized target values for specific quantifiable risk factors. Antiplatelet therapy in the form of aspirin or clopidogrel is routinely used for the prevention of ischemic stroke in patients who have had a transient ischemic attack or stroke. There is evidence from a recent trial that the use of combination antiplatelet therapy with aspirin and clopidogrel started within 24 hours of minor stroke or transient ischemic attack reduces the risk of recurrent stroke compared to the use of aspirin alone, and therefore we use aspirin plus clopidogrel in recently symptomatic patients with carotid stenosis pending carotid revascularization. Anticoagulation with heparins or vitamin K antagonist is not recommended except in patients at risk for cardio-embolic events. Lowering blood pressure to target levels has been shown to slow down the progression of carotid artery stenosis and reduces the intima-media thickness of the carotid plaque, while lowering lipid levels with statins has become an essential element in the medical therapy of carotid artery stenosis. Diabetes management should be optimized. Lifestyle choices, including tobacco smoking, physical inactivity, unhealthy diet, obesity, and excessive alcohol intake, are all important modifiable vascular risk factors. The combination of dietary modification, physical exercise, and use of aspirin, a statin, and an antihypertensive agent can be expected to give a cumulative relative stroke risk reduction of 80%. The evidence suggests that intensive medical therapy is so effective that carotid revascularization may no longer be necessary in many of the patients in whom carotid surgery or stenting is currently performed. Two large ongoing trials are therefore comparing the risks and benefits of carotid revascularization versus intensive medical therapy alone. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Effects of reflex-based self-defence training on police performance in simulated high-pressure arrest situations.

    PubMed

    Renden, Peter G; Savelsbergh, Geert J P; Oudejans, Raôul R D

    2017-05-01

    We investigated the effects of reflex-based self-defence training on police performance in simulated high-pressure arrest situations. Police officers received this training as well as a regular police arrest and self-defence skills training (control training) in a crossover design. Officers' performance was tested on several variables in six reality-based scenarios before and after each training intervention. Results showed improved performance after the reflex-based training, while there was no such effect of the regular police training. Improved performance could be attributed to better communication, situational awareness (scanning area, alertness), assertiveness, resolution, proportionality, control and converting primary responses into tactical movements. As officers trained complete violent situations (and not just physical skills), they learned to use their actions before physical contact for de-escalation but also for anticipation on possible attacks. Furthermore, they learned to respond against attacks with skills based on their primary reflexes. The results of this study seem to suggest that reflex-based self-defence training better prepares officers for performing in high-pressure arrest situations than the current form of police arrest and self-defence skills training. Practitioner Summary: Police officers' performance in high-pressure arrest situations improved after a reflex-based self-defence training, while there was no such effect of a regular police training. As officers learned to anticipate on possible attacks and to respond with skills based on their primary reflexes, they were better able to perform effectively.

  15. Quantum key distillation from Gaussian states by Gaussian operations.

    PubMed

    Navascués, M; Bae, J; Cirac, J I; Lewestein, M; Sanpera, A; Acín, A

    2005-01-14

    We study the secrecy properties of Gaussian states under Gaussian operations. Although such operations are useless for quantum distillation, we prove that it is possible to distill a secret key secure against any attack from sufficiently entangled Gaussian states with nonpositive partial transposition. Moreover, all such states allow for key distillation, when Eve is assumed to perform finite-size coherent attacks before the reconciliation process.

  16. Perineal evisceration secondary to a bite injury in a dog with an untreated perineal hernia

    PubMed Central

    McCarthy, Daniel; Lux, Cassie; Seibert, Rachel

    2016-01-01

    Emergency surgery was performed on a 6-year-old castrated male springer spaniel dog with evisceration of most of the small intestinal tract through the perineal region, secondary to a dog attack. This is the first report describing successful treatment of perineal evisceration secondary to dog attack at an untreated perineal hernia, employing abdominal and perineal approaches. PMID:27708442

  17. Cryptanalysis and Enhancement of Anonymity Preserving Remote User Mutual Authentication and Session Key Agreement Scheme for E-Health Care Systems.

    PubMed

    Amin, Ruhul; Islam, S K Hafizul; Biswas, G P; Khan, Muhammad Khurram; Li, Xiong

    2015-11-01

    The E-health care systems employ IT infrastructure for maximizing health care resources utilization as well as providing flexible opportunities to the remote patient. Therefore, transmission of medical data over any public networks is necessary in health care system. Note that patient authentication including secure data transmission in e-health care system is critical issue. Although several user authentication schemes for accessing remote services are available, their security analysis show that none of them are free from relevant security attacks. We reviewed Das et al.'s scheme and demonstrated their scheme lacks proper protection against several security attacks such as user anonymity, off-line password guessing attack, smart card theft attack, user impersonation attack, server impersonation attack, session key discloser attack. In order to overcome the mentioned security pitfalls, this paper proposes an anonymity preserving remote patient authentication scheme usable in E-health care systems. We then validated the security of the proposed scheme using BAN logic that ensures secure mutual authentication and session key agreement. We also presented the experimental results of the proposed scheme using AVISPA software and the results ensure that our scheme is secure under OFMC and CL-AtSe models. Moreover, resilience of relevant security attacks has been proved through both formal and informal security analysis. The performance analysis and comparison with other schemes are also made, and it has been found that the proposed scheme overcomes the security drawbacks of the Das et al.'s scheme and additionally achieves extra security requirements.

  18. Depredation of domestic herds by pumas based on farmer's information in Southern Brazil.

    PubMed

    Schulz, Francine; Printes, Rodrigo C; Oliveira, Larissa R

    2014-10-15

    Large carnivores such as pumas are frequently killed due to conflicts with human populations involving predation on domestic herds. In Southern Brazil, traditional pasture systems, where animals feed without specific husbandry practices is typical, becoming the herds vulnerable to puma attacks. The aim of this study was to examine the conflict between local people and pumas in a Protected Areas mosaic in southern Brazil. Forty-five face-to-face interviews with local people were performed during the year of 2011, using a structured questionnaire with open and closed questions about puma attack episodes in some farms. Based on responses, the conflict and puma attacks were described, and the characteristics of attacked farms and estimated financial losses were evaluated. The first respondents were indicated by the Local Environmental Agency, and the others were indicated by the first one and so on, which is known as "snow-ball" method. Our data suggested that pumas used to attack in unfavorable conditions of visibility (foggy days) and on easier prey (e.g. sheep). Most of the attacks reported were close to forested areas and were focused on free herds during feeding activities. Some farmers said they gave up their sheep breeding activity due to losses caused by puma attacks. However, some farmers could over estimate their losses. Moreover, pumas were considered a threat to domestic herds and respondents mentioned cases of illegal puma hunting in the area. The results of questionnaires suggested that puma attack episodes were related to fragmentation of their habitat associated to incorrect management of herds in the farms studied. The diagnosis of this type of conflict and the characterization of most attacked sites are extremely important to create strategies to prevent and control attacks by wild carnivores. Deep changes in husbandry practices added to educational programs should be implemented, in order to maintain the sustainability of rural activities as well as the survival of pumas in southern Brazil.

  19. Study of aerodynamic technology for single-cruise engine V/STOL fighter/attack aircraft

    NASA Technical Reports Server (NTRS)

    Driggers, H. H.; Powers, S. A.; Roush, R. T.

    1982-01-01

    A conceptual design analysis is performed on a single engine V/STOL supersonic fighter/attack concept powered by a series flow tandem fan propulsion system. Forward and aft mounted fans have independent flow paths for V/STOL operation and series flow in high speed flight. Mission, combat and V/STOL performance is calculated. Detailed aerodynamic estimates are made and aerodynamic uncertainties associated with the configuration and estimation methods identified. A wind tunnel research program is developed to resolve principal uncertainties and establish a data base for the baseline configuration and parametric variations.

  20. Test data report, low speed wind tunnel tests of a full scale lift/cruise-fan inlet, with engine, at high angles of attack

    NASA Technical Reports Server (NTRS)

    Shain, W. M.

    1978-01-01

    A low speed wind tunnel test of a fixed lip inlet with engine, was performed. The inlet was close coupled to a Hamilton Standard 1.4 meter, variable pitch fan driven by a lycoming T55-L-11A engine. Tests were conducted with various combinations of inlet angle of attack freestream velocities, and fan airflows. Data were recorded to define the inlet airflow separation boundaries, performance characteristics, and fan blade stresses. The test model, installation, instrumentation, test, data reduction and final data are described.

  1. Cross-layer design for intrusion detection and data security in wireless ad hoc sensor networks

    NASA Astrophysics Data System (ADS)

    Hortos, William S.

    2007-09-01

    A wireless ad hoc sensor network is a configuration for area surveillance that affords rapid, flexible deployment in arbitrary threat environments. There is no infrastructure support and sensor nodes communicate with each other only when they are in transmission range. The nodes are severely resource-constrained, with limited processing, memory and power capacities and must operate cooperatively to fulfill a common mission in typically unattended modes. In a wireless sensor network (WSN), each sensor at a node can observe locally some underlying physical phenomenon and sends a quantized version of the observation to sink (destination) nodes via wireless links. Since the wireless medium can be easily eavesdropped, links can be compromised by intrusion attacks from nodes that may mount denial-of-service attacks or insert spurious information into routing packets, leading to routing loops, long timeouts, impersonation, and node exhaustion. A cross-layer design based on protocol-layer interactions is proposed for detection and identification of various intrusion attacks on WSN operation. A feature set is formed from selected cross-layer parameters of the WSN protocol to detect and identify security threats due to intrusion attacks. A separate protocol is not constructed from the cross-layer design; instead, security attributes and quantified trust levels at and among nodes established during data exchanges complement customary WSN metrics of energy usage, reliability, route availability, and end-to-end quality-of-service (QoS) provisioning. Statistical pattern recognition algorithms are applied that use observed feature-set patterns observed during network operations, viewed as security audit logs. These algorithms provide the "best" network global performance in the presence of various intrusion attacks. A set of mobile (software) agents distributed at the nodes implement the algorithms, by moving among the layers involved in the network response at each active node and trust neighborhood, collecting parametric information and executing assigned decision tasks. The communications overhead due to security mechanisms and the latency in network response are thus minimized by reducing the need to move large amounts of audit data through resource-limited nodes and by locating detection/identification programs closer to audit data. If network partitioning occurs due to uncoordinated node exhaustion, data compromise or other effects of the attacks, the mobile agents can continue to operate, thereby increasing fault tolerance in the network response to intrusions. Since the mobile agents behave like an ant colony in securing the WSN, published ant colony optimization (ACO) routines and other evolutionary algorithms are adapted to protect network security, using data at and through nodes to create audit records to detect and respond to denial-of-service attacks. Performance evaluations of algorithms are performed by simulation of a few intrusion attacks, such as black hole, flooding, Sybil and others, to validate the ability of the cross-layer algorithms to enable WSNs to survive the attacks. Results are compared for the different algorithms.

  2. Buffet Load Alleviation

    NASA Technical Reports Server (NTRS)

    Ryall, T. G.; Moses, R. W.; Hopkins, M. A.; Henderson, D.; Zimcik, D. G.; Nitzsche, F.

    2004-01-01

    High performance aircraft are, by their very nature, often required to undergo maneuvers involving high angles of attack. Under these conditions unsteady vortices emanating from the wing and the fuselage will impinge on the twin fins (required for directional stability) causing excessive buffet loads, in some circumstances, to be applied to the aircraft. These loads result in oscillatory stresses, which may cause significant amounts of fatigue damage. Active control is a possible solution to this important problem. A full-scale test was carried out on an F/A-18 fuselage and fins using piezoceramic actuators to control the vibrations. Buffet loads were simulated using very powerful electromagnetic shakers. The first phase of this test was concerned with the open loop system identification whereas the second stage involved implementing linear time invariant control laws. This paper looks at some of the problems encountered as well as the corresponding solutions and some results. It is expected that flight trials of a similar control system to alleviate buffet will occur as early as 2001.

  3. Novel usage of fresh frozen plasma in hereditary angioedema.

    PubMed

    Hanizah, N; Affirul, C A; Farah, N A; Shamila, M A; Ridzuan, M I

    2016-01-01

    Hereditary angioedema (HAE) is a rare and potentially life threatening autosomal dominant disease characterized by recurrent episodes of cutaneous and mucosal oedema. It results from reduced expression or loss of function of CI-esterase inhibitors (C1-INH). As opposed to the more common histamine-mediated angioedema, HAE does not respond well to conventional treatments with anti-histamines, steroids and adrenaline. Early recognition and timely intervention with the correct treatment are crucial particularly preventing airway obstruction. New disease specific treatment including plasma derived or recombinant C1-INH, ecallantide and icatibant have recently emerged and its appropriate use can reduce HAE-associated mortality and morbidity. However due to its costs, these disease specific treatments have yet to reach Malaysia. Despite that no randomized clinical trial on FFP has been performed, its efficacy in treating acute attacks of HAE is only demonstrated in case studies. This case report illustrates the successful treatment of acute HAE episode with FFP in a Malaysian government hospital setting.

  4. Foveal and peripheral fields of vision influences perceptual skill in anticipating opponents' attacking position in volleyball.

    PubMed

    Schorer, Jörg; Rienhoff, Rebecca; Fischer, Lennart; Baker, Joseph

    2013-09-01

    The importance of perceptual-cognitive expertise in sport has been repeatedly demonstrated. In this study we examined the role of different sources of visual information (i.e., foveal versus peripheral) in anticipating volleyball attack positions. Expert (n = 11), advanced (n = 13) and novice (n = 16) players completed an anticipation task that involved predicting the location of volleyball attacks. Video clips of volleyball attacks (n = 72) were spatially and temporally occluded to provide varying amounts of information to the participant. In addition, participants viewed the attacks under three visual conditions: full vision, foveal vision only, and peripheral vision only. Analysis of variance revealed significant between group differences in prediction accuracy with higher skilled players performing better than lower skilled players. Additionally, we found significant differences between temporal and spatial occlusion conditions. Both of those factors interacted separately, but not combined with expertise. Importantly, for experts the sum of both fields of vision was superior to either source in isolation. Our results suggest different sources of visual information work collectively to facilitate expert anticipation in time-constrained sports and reinforce the complexity of expert perception.

  5. Improvement of maneuver aerodynamics by spanwise blowing

    NASA Technical Reports Server (NTRS)

    Erickson, G. E.; Campbell, J. F.

    1977-01-01

    Spanwise blowing was used to test a generalized wind-tunnel model to investigate component concepts in order to provide improved maneuver characteristics for advanced fighter aircraft. Primary emphasis was placed on performance, stability, and control at high angles of attack and subsonic speeds. Test data were obtained in the Langley high speed 7 by 10 foot tunnel at free stream Mach numbers up to 0.50 for a range of model angles of attack, jet momentum coefficients, and leading and trailing edge flap deflection angles. Spanwise blowing on a 44 deg swept trapezoidal wing resulted in leading edge vortex enhancement with subsequent large vortex induced lift increments and drag polar improvements at the higher angles of attack. Small deflections of a leading edge flap delayed these lift and drag benefits to higher angles of attack. In addition, blowing was more effective at higher Mach numbers. Spanwise blowing in conjunction with a deflected trailing edge flap resulted in lift and drag benefits that exceeded the summation of the effects of each high lift device acting alone. Asymmetric blowing was an effective lateral control device at the higher angles of attack.

  6. On the vulnerability of basic quantum key distribution protocols and three protocols stable to attack with 'blinding' of avalanche photodetectors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Molotkov, S. N., E-mail: sergei.molotkov@gmail.com

    2012-05-15

    The fundamental quantum mechanics prohibitions on the measurability of quantum states allow secure key distribution between spatially remote users to be performed. Experimental and commercial implementations of quantum cryptography systems, however, use components that exist at the current technology level, in particular, one-photon avalanche photodetectors. These detectors are subject to the blinding effect. It was shown that all the known basic quantum key distribution protocols and systems based on them are vulnerable to attacks with blinding of photodetectors. In such attacks, an eavesdropper knows all the key transferred, does not produce errors at the reception side, and remains undetected. Threemore » protocols of quantum key distribution stable toward such attacks are suggested. The security of keys and detection of eavesdropping attempts are guaranteed by the internal structure of protocols themselves rather than additional technical improvements.« less

  7. Interhemispheric balance patterns detected by selective phonemic dichotic laterality measures in four clinical subtypes of reading-disabled children.

    PubMed

    Morton, L L

    1994-08-01

    Identifying disabilities in word-attack, word-recognition, or reading comprehension, allowed for four categories of reading disability: (1) reading comprehension only (RC), (2) word-attack plus comprehension (WA+RC), (3) word-attack, word-recognition, and comprehension (WA+WR+RC), and (4) word-attack but not comprehension (WA-RC). Along with age-matched controls (AMC) and developmental-delay controls (DDC), the disabled were tested on a directed-attention dichotic task using consonant-vowel combinations. Laterality results for each place of articulation (i.e., bilabial, alveolar, and velar) selectively attested to greater left hemisphere involvement or engagement for the RC group and greater right hemisphere involvement or engagement for the WA+RC group. Performance of the other two disabled groups was consistent with less efficient right hemisphere involvement or callosal transfer. Implications for theory, research, and remediation are discussed.

  8. S-Boxes Based on Affine Mapping and Orbit of Power Function

    NASA Astrophysics Data System (ADS)

    Khan, Mubashar; Azam, Naveed Ahmed

    2015-06-01

    The demand of data security against computational attacks such as algebraic, differential, linear and interpolation attacks has been increased as a result of rapid advancement in the field of computation. It is, therefore, necessary to develop such cryptosystems which can resist current cryptanalysis and more computational attacks in future. In this paper, we present a multiple S-boxes scheme based on affine mapping and orbit of the power function used in Advanced Encryption Standard (AES). The proposed technique results in 256 different S-boxes named as orbital S-boxes. Rigorous tests and comparisons are performed to analyse the cryptographic strength of each of the orbital S-boxes. Furthermore, gray scale images are encrypted by using multiple orbital S-boxes. Results and simulations show that the encryption strength of the orbital S-boxes against computational attacks is better than that of the existing S-boxes.

  9. Free-Flight Evaluation of Forebody Blowing for Yaw Control at High Angels of Attack

    NASA Technical Reports Server (NTRS)

    Kiddy, Jason

    1995-01-01

    Forebody blowing is a concept developed to provide yaw control for aircraft flying at high angles of attack where a conventional rudder becomes ineffective. The basic concept is fairly simple. A small jet of air is forced out of the nose of the aircraft. This jet causes a repositioning of the forebody vortices in an asymmetrical fashion. The asymmetric forebody vortex flows develop a side force on the forebody which results in substantial yawing moments at high angles of attack. The purpose of this project was to demonstrate the use of forebody blowing as a control device through free-flight evaluation. This unique type of testing was performed at the NASA-Langley 30- by 60-foot tunnel. From these tests, it could then be shown that forebody blowing is an effective method of maintaining yaw control at high angles of attack.

  10. Security of subcarrier wave quantum key distribution against the collective beam-splitting attack.

    PubMed

    Miroshnichenko, G P; Kozubov, A V; Gaidash, A A; Gleim, A V; Horoshko, D B

    2018-04-30

    We consider a subcarrier wave quantum key distribution (QKD) system, where quantum encoding is carried out at weak sidebands generated around a coherent optical beam as a result of electro-optical phase modulation. We study security of two protocols, B92 and BB84, against one of the most powerful attacks for this class of systems, the collective beam-splitting attack. Our analysis includes the case of high modulation index, where the sidebands are essentially multimode. We demonstrate numerically and experimentally that a subcarrier wave QKD system with realistic parameters is capable of distributing cryptographic keys over large distances in presence of collective attacks. We also show that BB84 protocol modification with discrimination of only one state in each basis performs not worse than the original BB84 protocol in this class of QKD systems, thus significantly simplifying the development of cryptographic networks using the considered QKD technique.

  11. Quantum key distribution using continuous-variable non-Gaussian states

    NASA Astrophysics Data System (ADS)

    Borelli, L. F. M.; Aguiar, L. S.; Roversi, J. A.; Vidiella-Barranco, A.

    2016-02-01

    In this work, we present a quantum key distribution protocol using continuous-variable non-Gaussian states, homodyne detection and post-selection. The employed signal states are the photon added then subtracted coherent states (PASCS) in which one photon is added and subsequently one photon is subtracted from the field. We analyze the performance of our protocol, compared with a coherent state-based protocol, for two different attacks that could be carried out by the eavesdropper (Eve). We calculate the secret key rate transmission in a lossy line for a superior channel (beam-splitter) attack, and we show that we may increase the secret key generation rate by using the non-Gaussian PASCS rather than coherent states. We also consider the simultaneous quadrature measurement (intercept-resend) attack, and we show that the efficiency of Eve's attack is substantially reduced if PASCS are used as signal states.

  12. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hoette, Trisha Marie

    Throughout history, as new chemical threats arose, strategies for the defense against chemical attacks have also evolved. As a part of an Early Career Laboratory Directed Research and Development project, a systems analysis of past, present, and future chemical terrorism scenarios was performed to understand how the chemical threats and attack strategies change over time. For the analysis, the difficulty in executing chemical attack was evaluated within a framework of three major scenario elements. First, historical examples of chemical terrorism were examined to determine how the use of chemical threats, versus other weapons, contributed to the successful execution of themore » attack. Using the same framework, the future of chemical terrorism was assessed with respect to the impact of globalization and new technologies. Finally, the efficacy of the current defenses against contemporary chemical terrorism was considered briefly. The results of this analysis justify the need for continued diligence in chemical defense.« less

  13. A robust anonymous biometric-based authenticated key agreement scheme for multi-server environments

    PubMed Central

    Huang, Yuanfei; Ma, Fangchao

    2017-01-01

    In order to improve the security in remote authentication systems, numerous biometric-based authentication schemes using smart cards have been proposed. Recently, Moon et al. presented an authentication scheme to remedy the flaws of Lu et al.’s scheme, and claimed that their improved protocol supports the required security properties. Unfortunately, we found that Moon et al.’s scheme still has weaknesses. In this paper, we show that Moon et al.’s scheme is vulnerable to insider attack, server spoofing attack, user impersonation attack and guessing attack. Furthermore, we propose a robust anonymous multi-server authentication scheme using public key encryption to remove the aforementioned problems. From the subsequent formal and informal security analysis, we demonstrate that our proposed scheme provides strong mutual authentication and satisfies the desirable security requirements. The functional and performance analysis shows that the improved scheme has the best secure functionality and is computational efficient. PMID:29121050

  14. A robust anonymous biometric-based authenticated key agreement scheme for multi-server environments.

    PubMed

    Guo, Hua; Wang, Pei; Zhang, Xiyong; Huang, Yuanfei; Ma, Fangchao

    2017-01-01

    In order to improve the security in remote authentication systems, numerous biometric-based authentication schemes using smart cards have been proposed. Recently, Moon et al. presented an authentication scheme to remedy the flaws of Lu et al.'s scheme, and claimed that their improved protocol supports the required security properties. Unfortunately, we found that Moon et al.'s scheme still has weaknesses. In this paper, we show that Moon et al.'s scheme is vulnerable to insider attack, server spoofing attack, user impersonation attack and guessing attack. Furthermore, we propose a robust anonymous multi-server authentication scheme using public key encryption to remove the aforementioned problems. From the subsequent formal and informal security analysis, we demonstrate that our proposed scheme provides strong mutual authentication and satisfies the desirable security requirements. The functional and performance analysis shows that the improved scheme has the best secure functionality and is computational efficient.

  15. Granma: Cuban News and Propaganda Analysis for the Period, 1-31 December 1984.

    DTIC Science & Technology

    1984-12-01

    homeless people in New York City. Over 7,000 are mentally ill and have been dis- charged from mental institutions. The rest are young people who have no...attacked targets of the University of Puerto Rico and a U.S. Army recruiting office. * The military in Argentina are concerned about the civilian trial of...and troop deploy- ments in the Middle East and Asia. * The Indian government uncovers another CIA spy agency. The Solidarity International Press

  16. Through Trial and Error: Learning and Adaptation in the English Tactical System from Bannockburn to Poitiers

    DTIC Science & Technology

    2014-06-13

    continue to conduct irregular warfare through raids and ambushes. As the English vanguard approached, leery of attack from Scots in the wooded area... Scots , did not enter the wood line of New Park either. Robert the Bruce had successfully avoided battle with the English and repelled their...pulling back, to force the Scots further into the field so they could not retreat easily into the wood line, but his idea was challenged by a

  17. Non-mydriatic ocular fundus photography in the emergency department: how it can benefit neurologists

    PubMed Central

    Bruce, Beau B.

    2016-01-01

    Examination of the ocular fundus is a critical aspect of the neurological examination. For example, in patients with headache the ocular fundus examination is needed to uncover “red flags” suggestive of secondary etiologies. However, ocular fundus examination is infrequently and poorly performed in clinical practice. Non-mydriatic ocular fundus photography provides an alternative to direct ophthalmoscopy that has been studied as part of the Fundus photography vs. Ophthalmoscopy Trial Outcomes in the Emergency Department (FOTO-ED) study. Herein, we review the results of the FOTO-ED study with a particular focus on the study's implications for the acute care of patients presenting with headache and focal neurologic deficits. In headache patients, we not only observed optic disc edema and optic disc pallor as would be expected, but also a large number of abnormalities associated with hypertension. Based upon subjects with focal neurological deficits, the FOTO-ED study suggests that the ocular fundus examination may assist with the triage of patients presenting with suspected transient ischemic attack. Continued advances in the ease and portability of non-mydriatic fundus photography will hopefully help to restore ocular fundus examination as a routinely performed component of all neurological examinations. PMID:26444394

  18. Acupuncture for the prevention of episodic migraine

    PubMed Central

    Linde, Klaus; Allais, Gianni; Brinkhaus, Benno; Fei, Yutong; Mehring, Michael; Vertosick, Emily A.; Vickers, Andrew; White, Adrian R

    2016-01-01

    Background Acupuncture is often used for migraine prevention but its effectiveness is still controversial. We present an update of our Cochrane review from 2009. Objectives To investigate whether acupuncture is a) more effective than no prophylactic treatment/routine care only; b) more effective than sham (placebo) acupuncture; and c) as effective as prophylactic treatment with drugs in reducing headache frequency in adults with episodic migraine. Search methods We searched the Cochrane Central Register of Controlled Trials (CENTRAL: 2016, issue 1); MEDLINE (via Ovid, 2008 to January 2016); Ovid EMBASE (2008 to January 2016); and Ovid AMED (1985 to January 2016). We checked PubMed for recent publications to April 2016. We searched the World Health Organization (WHO) Clinical Trials Registry Platform to February 2016 for ongoing and unpublished trials. Selection criteria We included randomized trials at least eight weeks in duration that compared an acupuncture intervention with a no-acupuncture control (no prophylactic treatment or routine care only), a sham-acupuncture intervention, or prophylactic drug in participants with episodic migraine. Data collection and analysis Two reviewers checked eligibility; extracted information on participants, interventions, methods and results, and assessed risk of bias and quality of the acupuncture intervention. The primary outcome was migraine frequency (preferably migraine days, attacks or headache days if migraine days not measured/reported) after treatment and at follow-up. The secondary outcome was response (at least 50% frequency reduction). Safety outcomes were number of participants dropping out due to adverse effects and number of participants reporting at least one adverse effect. We calculated pooled effect size estimates using a fixed-effect model. We assessed the evidence using GRADE and created ’Summary of findings’ tables. Main results Twenty-two trials including 4985 participants in total (median 71, range 30 to 1715) met our updated selection criteria. We excluded five previously included trials from this update because they included people who had had migraine for less than 12 months, and included five new trials. Five trials had a no-acupuncture control group (either treatment of attacks only or non-regulated routine care), 15 a sham-acupuncture control group, and five a comparator group receiving prophylactic drug treatment. In comparisons with no-acupuncture control groups and groups receiving prophylactic drug treatment, there was risk of performance and detection bias as blinding was not possible. Overall the quality of the evidence was moderate. Comparison with no acupuncture Acupuncture was associated with a moderate reduction of headache frequency over no acupuncture after treatment (four trials, 2199 participants; standardised mean difference (SMD) −0.56; 95% CI −0.65 to −0.48); findings were statistically heterogeneous (I2 = 57%; moderate quality evidence). After treatment headache frequency at least halved in 41% of participants receiving acupuncture and 17% receiving no acupuncture (pooled risk ratio (RR) 2.40; 95% CI 2.08 to 2.76; 4 studies, 2519 participants) with a corresponding number needed to treat for an additional beneficial outcome (NNTB) of 4 (95% CI 3 to 6); there was no indication of statistical heterogeneity (I2 = 7%; moderate quality evidence). The only trial with post-treatment follow-up found a small but significant benefit 12 months after randomisation (RR 2.16; 95% CI 1.35 to 3.45; NNT 7; 95% 4 to 25; 377 participants, low quality evidence). Comparison with sham acupuncture Both after treatment (12 trials, 1646 participants) and at follow-up (10 trials, 1534 participants), acupuncture was associated with a small but statistically significant frequency reduction over sham (moderate quality evidence). The SMD was −0.18 (95% CI −0.28 to −0.08; I2 = 47%) after treatment and −0.19 (95% CI −0.30 to −0.09; I2 = 59%) at follow-up. After treatment headache frequency at least halved in 50% of participants receiving true acupuncture and 41% receiving sham acupuncture (pooled RR 1.23, 95% CI 1.11 to 1.36; I2 = 48%; 14 trials, 1825 participants) and at follow-up in 53% and 42%, respectively (pooled RR 1.25, 95% CI 1.13 to 1.39 ; I2 = 61%; 11 trials, 1683 participants; moderate quality evidence). The corresponding NNTBs are 11 (95% CI 7.00 to 20.00) and 10 (95% CI 6.00 to 18.00), respectively. The number of participants dropping out due to adverse effects (odds ratio (OR) 2.84; 95% CI 0.43 to 18.71; 7 trials, 931 participants; low quality evidence) and the number of participants reporting adverse effects (OR 1.15; 95% CI 0.85 to 1.56; 4 trials, 1414 participants; moderate quality evidence) did not differ significantly between acupuncture and sham groups. Comparison with prophylactic drug treatment Acupuncture reduced migraine frequency significantly more than drug prophylaxis after treatment (SMD −0.25; 95% CI −0.39 to −0.10; 3 trials, 739 participants), but the significance was not maintained at follow-up (SMD −0.13; 95% CI −0.28 to 0.01; 3 trials, 744 participants; moderate quality evidence). After three months headache frequency at least halved in 57% of participants receiving acupuncture and 46% receiving prophylactic drugs (pooled RR 1.24; 95% CI 1.08 to 1.44) and after six months in 59% and 54%, respectively (pooled RR 1.11; 95% CI 0.97 to 1.26; moderate quality evidence). Findings were consistent among trials with I2 being 0% in all analyses. Trial participants receiving acupuncture were less likely to drop out due to adverse effects (OR 0.27; 95% CI 0.08 to 0.86; 4 trials, 451 participants) and to report adverse effects (OR 0.25; 95% CI 0.10 to 0.62; 5 trials 931 participants) than participants receiving prophylactic drugs (moderate quality evidence). Authors’ conclusions The available evidence suggests that adding acupuncture to symptomatic treatment of attacks reduces the frequency of headaches. Contrary to the previous findings, the updated evidence also suggests that there is an effect over sham, but this effect is small. The available trials also suggest that acupuncture may be at least similarly effective as treatment with prophylactic drugs. Acupuncture can be considered a treatment option for patients willing to undergo this treatment. As for other migraine treatments, long-term studies, more than one year in duration, are lacking. PMID:27351677

  19. The system of technical diagnostics of the industrial safety information network

    NASA Astrophysics Data System (ADS)

    Repp, P. V.

    2017-01-01

    This research is devoted to problems of safety of the industrial information network. Basic sub-networks, ensuring reliable operation of the elements of the industrial Automatic Process Control System, were identified. The core tasks of technical diagnostics of industrial information safety were presented. The structure of the technical diagnostics system of the information safety was proposed. It includes two parts: a generator of cyber-attacks and the virtual model of the enterprise information network. The virtual model was obtained by scanning a real enterprise network. A new classification of cyber-attacks was proposed. This classification enables one to design an efficient generator of cyber-attacks sets for testing the virtual modes of the industrial information network. The numerical method of the Monte Carlo (with LPτ - sequences of Sobol), and Markov chain was considered as the design method for the cyber-attacks generation algorithm. The proposed system also includes a diagnostic analyzer, performing expert functions. As an integrative quantitative indicator of the network reliability the stability factor (Kstab) was selected. This factor is determined by the weight of sets of cyber-attacks, identifying the vulnerability of the network. The weight depends on the frequency and complexity of cyber-attacks, the degree of damage, complexity of remediation. The proposed Kstab is an effective integral quantitative measure of the information network reliability.

  20. Time-motion analysis of goalball players in attacks: differences of the player positions and the throwing techniques.

    PubMed

    Monezi, Lucas Antônio; Magalhães, Thiago Pinguelli; Morato, Márcio Pereira; Mercadante, Luciano Allegretti; Furtado, Otávio Luis Piva da Cunha; Misuta, Milton Shoiti

    2018-03-26

    In this study, we aimed to analyse goalball players time-motion variables (distance covered, time spent, maximum and average velocities) in official goalball match attacks, taking into account the attack phases (preparation and throwing), player position (centres and wings) and throwing techniques (frontal, spin and between the legs). A total of 365 attacks were assessed using a video based method (2D) through manual tracking using the Dvideo system. Inferential non-parametric statistics were applied for comparison of preparation vs. throwing phase, wings vs. centres and, among the throwing techniques, frontal, spin and between the legs. Significant differences were found between the attack preparation versus the throwing phase for all player time-motion variables: distance covered, time spent, maximum player velocity and average player velocity. Wing players performed most of the throws (85%) and covered longer distances than centres (1.65 vs 0.31 m). The between the legs and the spin throwing techniques presented greater values for most of the time-motion variables (distance covered, time spent and maximum player velocity) than did the frontal technique in both attack phases. These findings provide important information regarding players' movement patterns during goalball matches that can be used to plan more effective training.

  1. Elucidation of defense-related signaling responses to spot blotch infection in bread wheat (Triticum aestivum L.).

    PubMed

    Sahu, Ranabir; Sharaff, Murali; Pradhan, Maitree; Sethi, Avinash; Bandyopadhyay, Tirthankar; Mishra, Vinod K; Chand, Ramesh; Chowdhury, Apurba K; Joshi, Arun K; Pandey, Shree P

    2016-04-01

    Spot blotch disease, caused by Bipolaris sorokiniana, is an important threat to wheat, causing an annual loss of ~17%. Under epidemic conditions, these losses may be 100%, yet the molecular responses of wheat to spot blotch remain almost uncharacterized. Moreover, defense-related phytohormone signaling genes have been poorly characterized in wheat. Here, we have identified 18 central components of salicylic acid (SA), jasmonic acid (JA), ethylene (ET), and enhanced disease susceptibility 1 (EDS1) signaling pathways as well as the genes of the phenylpropanoid pathway in wheat. In time-course experiments, we characterized the reprogramming of expression of these pathways in two contrasting genotypes: Yangmai #6 (resistant to spot blotch) and Sonalika (susceptible to spot blotch). We further evaluated the performance of a population of recombinant inbred lines (RILs) by crossing Yangmai#6 and Sonalika (parents) and subsequent selfing to F10 under field conditions in trials at multiple locations. We characterized the reprogramming of defense-related signaling in these RILs as a consequence of spot blotch attack. During resistance to spot blotch attack, wheat strongly elicits SA signaling (SA biogenesis as well as the NPR1-dependent signaling pathway), along with WRKY33 transcription factor, followed by an enhanced expression of phenylpropanoid pathway genes. These may lead to accumulation of phenolics-based defense metabolites that may render resistance against spot blotch. JA signaling may synergistically contribute to the resistance. Failure to elicit SA (and possibly JA) signaling may lead to susceptibility against spot blotch infection in wheat. © 2016 The Authors The Plant Journal © 2016 John Wiley & Sons Ltd.

  2. Potential for Controlling Cholera Using a Ring Vaccination Strategy: Re-analysis of Data from a Cluster-Randomized Clinical Trial.

    PubMed

    Ali, Mohammad; Debes, Amanda K; Luquero, Francisco J; Kim, Deok Ryun; Park, Je Yeon; Digilio, Laura; Manna, Byomkesh; Kanungo, Suman; Dutta, Shanta; Sur, Dipika; Bhattacharya, Sujit K; Sack, David A

    2016-09-01

    Vaccinating a buffer of individuals around a case (ring vaccination) has the potential to target those who are at highest risk of infection, reducing the number of doses needed to control a disease. We explored the potential vaccine effectiveness (VE) of oral cholera vaccines (OCVs) for such a strategy. This analysis uses existing data from a cluster-randomized clinical trial in which OCV or placebo was given to 71,900 participants in Kolkata, India, from 27 July to 10 September 2006. Cholera surveillance was then conducted on 144,106 individuals living in the study area, including trial participants, for 5 y following vaccination. First, we explored the risk of cholera among contacts of cholera patients, and, second, we measured VE among individuals living within 25 m of cholera cases between 8 and 28 d after onset of the index case. For the first analysis, individuals living around each index case identified during the 5-y period were assembled using a ring to define cohorts of individuals exposed to cholera index cases. An index control without cholera was randomly selected for each index case from the same population, matched by age group, and individuals living around each index control were assembled using a ring to define cohorts not exposed to cholera cases. Cholera attack rates among the exposed and non-exposed cohorts were compared using different distances from the index case/control to define the rings and different time frames to define the period at risk. For the VE analysis, the exposed cohorts were further stratified according to the level of vaccine coverage into high and low coverage strata. Overall VE was assessed by comparing the attack rates between high and low vaccine coverage strata irrespective of individuals' vaccination status, and indirect VE was assessed by comparing the attack rates among unvaccinated members between high and low vaccine coverage strata. Cholera risk among the cohort exposed to cholera cases was 5-11 times higher than that among the cohort not exposed to cholera cases. The risk gradually diminished with an increase in distance and time. The overall and indirect VE measured between 8 and 28 d after exposure to a cholera index case during the first 2 y was 91% (95% CI 62%-98%) and 93% (95% CI 44%-99%), respectively. VE persisted for 5 y after vaccination and was similar whether the index case was a young child (<5 y) or was older. Of note, this study was a reanalysis of a cholera vaccine trial that used two doses; thus, a limitation of the study relates to the assumption that a single dose, if administered quickly, will induce a similar level of total and indirect protection over the short term as did two doses. These findings suggest that high-level protection can be achieved if individuals living close to cholera cases are living in a high coverage ring. Since this was an observational study including participants who had received two doses of vaccine (or placebo) in the clinical trial, further studies are needed to determine whether a ring vaccination strategy, in which vaccine is given quickly to those living close to a case, is feasible and effective. ClinicalTrials.gov NCT00289224.

  3. Internet-based information-seeking behavior for transient ischemic attack.

    PubMed

    Abedi, Vida; Mbaye, Marieme; Tsivgoulis, Georgios; Male, Shailesh; Goyal, Nitin; Alexandrov, Andrei V; Zand, Ramin

    2015-12-01

    In recent years, Internet became an increasingly important tool for accessing health information and is being used more frequently to promote public health. To use Google search data to explore information seeking behavior for transient ischemic attack. We selected two groups of keywords related to transient ischemic attack: 'Transient Ischemic Attack' and 'Mini Stroke'. We obtained all available online search data performed in the United States from the Google search engine for a 10-year span--January 2004 to December 2013. The monthly and daily search data for the selected keywords were analyzed--using moving average--to explore the trends, peaks, and declining effects. There were three significant concurrent peaks in the Google search data for the selected keywords. Each peak was directly associated with media coverage and news headlines related to the incident of transient ischemic attack in a public figure. Following each event, it took three- to seven-days for the search trend to return to its respective average value. Furthermore, the trend was steady for 'Transient Ischemic Attack'; however, the search interest for the keyword 'Mini Stroke' shows a steady increase. The overall search interest for the selected keywords was significantly higher in the southeastern United States. Our study shows that changes in online search behavior can be associated with media coverage of key events (in our case transient ischemic attack) in public figures. These findings suggest that multimedia health promotion campaigns might be more effective, if increased promptly after similar media coverage. © 2015 World Stroke Organization.

  4. Hydrodynamic characteristics of the oval cambered double slotted otter board in bottom trawl fisheries

    NASA Astrophysics Data System (ADS)

    Liu, J.; Huang, H. L.; Li, L. Z.; Qu, T. C.; Wu, Y.; Chen, S.; Yang, J. L.; Rao, X.

    2017-07-01

    The otter board is one of the main components of single boat trawl fisheries. An oval cambered double slotted otter board was developed for improving the expansion performance of trawl net in bottom trawl fisheries. A flume model experiment was conducted to measure the lift coefficient (C L), drag coefficient (C D), and lift to drag ratio (K) in different angles of attack (α). The experimental results are as follows : (1) The C L and K value show a trend of increasing at the beginning and then decreasing with the increase of angle of attack, the C D value reflects an upward trend as the angle of attack increases; (2) The D3 otter board (front flow deflector angle at 29°) showed a better hydrodynamic performance. When α=30°, the max lift coefficient (C Lmax) was 1.464, in this case C D = 0.554 and K=2.643. When α=15°, the max lift to drag ratio (K max) was 4.165, C L =0.633, and C D = 0.152. This suggests that the best working scope for the angle of attack is between 15°~30°, in which case, C L>0.633 and K>2.643. The mean value of the lift coefficient was 1.071 and the mean of the lift to drag ratio was 3.482. Comparative analysis of the hydrodynamic performance of different types of otter boards showed that the D3 otter board both had good expansion performance and efficiency, which can provide a reference basis for further optimization of the bottom trawl otter board.

  5. Plasma Control of Separated Flows on Delta Wings at High Angles of Attack

    DTIC Science & Technology

    2009-03-18

    of Attack 5a. CONTRACT NUMBER ISTC Registration No: 3646 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Dr. Anatoly Alexandrovich...NUMBER(S) ISTC 06-7002 12. DISTRIBUTION/AVAILABILITY STATEMENT Approved for public release; distribution is unlimited. 13. SUPPLEMENTARY...This work is supported financially by EOARD and performed under the agreement with the International Science and Technology Center ( ISTC ), Moscow

  6. Medical Surveillance Monthly Report (MSMR). Volume 15, Number 5, June 2008

    DTIC Science & Technology

    2008-06-01

    attacks, the severity of symptoms during attacks, the impacts on military operational performance, and health care costs. However, the management of...health status as reported on deployment health assesment forms, U.S. Armed Forces, June 2007-May 2008 (Figure 2). For example, prior to...transmitted Environmental Lyme disease Malaria Chlamydia Gonorrhea Syphilis‡ Urethritis§ Cold Heat 2007 2008 2007 2008 2007 2008 2007 2008 2007 2008 2007

  7. The United States, the South Atlantic, and Antarctic: Interests and Challenges

    DTIC Science & Technology

    1990-06-01

    3) Probability of attack from the South was greatest in 1962. Not since the Navy’s 4th Fleet was based in northern Brazil during the Second World...Brazil’s attack aircraft are not carrier-borne. Brazil possesses a well-developed military armaments industry like Argentina, but its export sector far...release; ,. DECLASSIFICATIONJDOWNGRADING SCHEDULE distribution is unlimited PERFORMING ORGANIZATION REPORT NUMBER( S ) 5. MONITORING ORGANIZATION REPORT

  8. Achieving Homeland Security in a Time of Diminishing Resources

    DTIC Science & Technology

    2012-06-08

    and merged over 22 federal agencies and programs under the DHS umbrella. The overall mission of DHS is to enact “ a concerted national effort to ensure... A concerted national effort to prevent terrorist attacks within the United States; reduce America’s vulnerability to terrorism, major disasters...activity or effort performed to protect a nation against attack or other threats National Security. Requirement to maintain the survival of the state

  9. H-1 Upgrades (4BW/4BN) (H-1 Upgrades)

    DTIC Science & Technology

    2015-12-01

    automatic blade fold of the new composite rotor blades, new performance matched transmissions, a new four-bladed tail rotor and drive system, upgraded...Upgrades December 2015 SAR March 18, 2016 10:59:17 UNCLASSIFIED 4 Col Steven Girard PMA-276 USMC Light/Attack Helicopter Program Executive Officer...attack helicopter is to provide rotary wing close air support, anti-armor, armed escort, armed/visual reconnaissance and fire support coordination

  10. Space occupation near the basket shapes collective behaviours in youth basketball.

    PubMed

    Esteves, Pedro T; Silva, Pedro; Vilar, Luís; Travassos, Bruno; Duarte, Ricardo; Arede, Jorge; Sampaio, Jaime

    2016-08-01

    This study aimed to analyse how youth basketball players explored numerical overloads during shot attempts by measuring their space occupation across specific court areas. Four process-tracing variables measured how the number of attackers (NA), number of defenders (ND), interpersonal distance between attacker and the closest defender (ID) and distance between attacker and the basket (DBkt) impacted on the performance outcome (converted shot; missed shot; ball possession lost). Ten competitive games involving 13 U14 teams were video recorded and players' displacements were digitised. The associations between performance outcomes and the process-tracing measures were assessed using standardised mean differences and a cross-correlation function. A multinomial logistic regression was used to calculate the odds ratio (OR) for each of the three possible outcomes. Results revealed that when shot attempts occurred at larger ID and at smaller DBkt, the possibilities to obtain a converted shot increased. The numerical overload of defenders near the scoring target was predominantly associated with offensive success. Also, the possibility of attackers to lead the spatial relation of movements with the defenders, near the scoring target, appeared as a prominent strategy to succeed. In sum, basketball teams that exhibit potential to adapt their collective behaviours to local changes in the environment might be closer to achieving successful outcomes.

  11. Tocotrienol vitamin E protects against preclinical canine ischemic stroke by inducing arteriogenesis.

    PubMed

    Rink, Cameron; Christoforidis, Greg; Khanna, Savita; Peterson, Laura; Patel, Yojan; Khanna, Suchin; Abduljalil, Amir; Irfanoglu, Okan; Machiraju, Raghu; Bergdall, Valerie K; Sen, Chandan K

    2011-11-01

    Vitamin E consists of tocopherols and tocotrienols, in which α-tocotrienol is the most potent neuroprotective form that is also effective in protecting against stroke in rodents. As neuroprotective agents alone are insufficient to protect against stroke, we sought to test the effects of tocotrienol on the cerebrovascular circulation during ischemic stroke using a preclinical model that enables fluoroscopy-guided angiography. Mongrel canines (mean weight=26.3±3.2 kg) were supplemented with tocotrienol-enriched (TE) supplement (200 mg b.i.d, n=11) or vehicle placebo (n=9) for 10 weeks before inducing transient middle cerebral artery (MCA) occlusion. Magnetic resonance imaging was performed 1 hour and 24 hours post reperfusion to assess stroke-induced lesion volume. Tocotrienol-enriched supplementation significantly attenuated ischemic stroke-induced lesion volume (P<0.005). Furthermore, TE prevented loss of white matter fiber tract connectivity after stroke as evident by probabilistic tractography. Post hoc analysis of cerebral angiograms during MCA occlusion revealed that TE-supplemented canines had improved cerebrovascular collateral circulation to the ischemic MCA territory (P<0.05). Tocotrienol-enriched supplementation induced arteriogenic tissue inhibitor of metalloprotease 1 and subsequently attenuated the activity of matrix metalloproteinase-2. Outcomes of the current preclinical trial set the stage for a clinical trial testing the effects of TE in patients who have suffered from transient ischemic attack and are therefore at a high risk for stroke.

  12. A computational/experimental study of the flow around a body of revolution at angle of attack

    NASA Technical Reports Server (NTRS)

    Zilliac, Gregory G.

    1986-01-01

    The incompressible Navier-Stokes equations are numerically solved for steady flow around an ogive-cylinder (fineness ration 4.5) at angle of attack. The three-dimensional vortical flow is investigated with emphasis on the tip and the near wake region. The implicit, finite-difference computation is performed on the CRAY X-MP computer using the method of pseudo-compressibility. Comparisons of computational results with results of a companion towing tank experiment are presented for two symmetric leeside flow cases of moderate angles of attack. The topology of the flow is discussed and conclusions are drawn concerning the growth and stability of the primary vortices.

  13. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Almajali, Anas; Rice, Eric; Viswanathan, Arun

    This paper presents a systems analysis approach to characterizing the risk of a Smart Grid to a load-drop attack. A characterization of the risk is necessary for the design of detection and remediation strategies to address the consequences of such attacks. Using concepts from systems health management and system engineering, this work (a) first identifies metrics that can be used to generate constraints for security features, and (b) lays out an end-to-end integrated methodology using separate network and power simulations to assess system risk. We demonstrate our approach by performing a systems-style analysis of a load-drop attack implemented over themore » AMI subsystem and targeted at destabilizing the underlying power grid.« less

  14. Navier-Stokes analysis of airfoils with leading edge ice accretions

    NASA Technical Reports Server (NTRS)

    Potapczuk, Mark G.

    1993-01-01

    A numerical analysis of the flowfield characteristics and the performance degradation of an airfoil with leading edge ice accretions was performed. The important fluid dynamic processes were identified and calculated. Among these were the leading edge separation bubble at low angles of attack, complete separation on the low pressure surface resulting in premature shell, drag rise due to the ice shape, and the effects of angle of attack on the separated flow field. Comparisons to experimental results were conducted to confirm these calculations. A computer code which solves the Navier-Stokes equations in two dimensions, ARC2D, was used to perform the calculations. A Modified Mixing Length turbulence model was developed to produce grids for several ice shape and airfoil combinations. Results indicate that the ability to predict overall performance characteristics, such as lift and drag, at low angles of attack is excellent. Transition location is important for accurately determining separation bubble shape. Details of the flowfield in and downstream of the separated regions requires some modifications. Calculations for the stalled airfoil indicate periodic shedding of vorticity that was generated aft of the ice accretion. Time averaged pressure values produce results which compare favorably with experimental information. A turbulence model which accounts for the history effects in the flow may be justified.

  15. Attacking and defensive styles of play in soccer: analysis of Spanish and English elite teams.

    PubMed

    Fernandez-Navarro, Javier; Fradua, Luis; Zubillaga, Asier; Ford, Paul R; McRobert, Allistair P

    2016-12-01

    The aim of this study was to define and categorise different styles of play in elite soccer and associated performance indicators by using factor analysis. Furthermore, the observed teams were categorised using all factor scores. Data were collected from 97 matches from the Spanish La Liga and the English Premier League from the seasons 2006-2007 and 2010-2011 using the Amisco® system. A total of 19 performance indicators, 14 describing aspects of attacking play and five describing aspects of defensive play, were included in the factor analysis. Six factors, representing 12 different styles of play (eight attacking and four defensive), had eigenvalues greater than 1 and explained 87.54% of the total variance. Direct and possession styles of play, defined by factor 1, were the most apparent styles. Factor analysis used the performance indicators to cluster each team's style of play. Findings showed that a team's style of play was defined by specific performance indicators and, consequently, teams can be classified to create a playing style profile. For practical implications, playing styles profiling can be used to compare different teams and prepare for opponents in competition. Moreover, teams could use specific training drills directed to improve their styles of play.

  16. Tongxinluo (Tong xin luo or Tong-xin-luo) capsule for unstable angina pectoris.

    PubMed

    Wu, Taixiang; Harrison, R A; Chen, Xiaoyan; Ni, Juan; Zhou, Likun; Qiao, Jieqi; Wang, Qin; Wei, Jiafu; Xin, Duan; Zheng, Jie

    2006-10-18

    Tongxinluo capsule is a medicine consisting of traditional Chinese herbs and insects used for cardiovascular diseases in China and some other Asian countries. To date the evidence of its effect has not previously been subject to systematic review, making it difficult to derive robust conclusions about its actual benefits, and indeed, possible harms. To assess systematically the effects of tongxinluo capsule in people with unstable angina pectoris. We searched the Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library, Issue 4 2004, MEDLINE, EMBASE, Chinese Biomedical Database, China National Knowledge Infrastructure, Japana Centra Revuo Medicina (all 1995 to 2005). We also handsearched the relevant Chinese journals, checked with manufacturers and registers of ongoing studies. Randomised trials comparing either tongxinluo capsule only or standard treatment plus tongxinluo capsule with standard treatment or other anti-angina pectoris drugs, placebo or no intervention. Two authors identified relevant studies for the review independently and went on to abstract data, and assess trial quality. Authors of included studies were contacted to obtain further information as required. 18 short term follow-up trials involving 1413 people were included. The studies did not provide strong support of a benefit of tongxinluo for reducing the combined outcome of acute myocardial infarction, angioplasty (PTCA) coronary artery bypass graft (CABG) and sudden death or all-cause mortality (RR 0.42, 95% CI 0.07 to 2.59, P=0.35; RR 0.33, 95% CI 0.01to 7.78, P=0.49, respectively). Tongxinluo reduced the frequency of acute angina attacks (WMD -1.20, 95%CI -1.38 to -1.02, P<0.00001 and RR -2.36, 95%CI -2.53 to -2.18, P<0.00001, respectively), improved ECG (RR 1.31, 95% CI 1.08 to 1.57, P=0.005) and angina symptoms (RR 1.21, 95% CI 1.06 to 1.40; P=0.007). Tongxinluo in combination with routine angina therapy appears to reduce the risk of subsequent AMI, PTCA or CABG, angina attacks and severity, as well as improving symptoms and ischaemic changes on the electrocardiogram (ECG). Due to the methodological limitations of the studies, the evidence is insufficient to make any conclusive recommendations about the use of this treatment for patients presenting with unstable angina. Large high quality randomised controlled trials are warranted.

  17. Recurrent abdominal pain in childhood urolithiasis.

    PubMed

    Polito, Cesare; La Manna, Angela; Signoriello, Giuseppe; Marte, Antonio

    2009-12-01

    Our goal was to establish the clinical presentation and features of pain attacks in children with recurrent abdominal pain (RAP) and urolithiasis. We compared the rate of previous appendectomy among 100 consecutive patients with that of 270 control subjects. We also compared the frequency of pain attacks with that reported by children with functional or organic gastrointestinal RAP. Fifty-three patients had no history of dysuria or gross hematuria, and only 35 had hematuria at the first visit; 41 patients were evaluated for urolithiasis only because of a family history of kidney stones associated with RAP. Twenty-nine patients had been previously hospitalized for abdominal symptoms. Sixteen patients and 4 control subjects (1.5%) had undergone a previous appendectomy (P < .0001). Two to 28 months before the diagnosis of urolithiasis, 37 patients underwent abdominal ultrasonography, which did not show urinary stones. Sixty-nine percent of subjects younger than 8 years of age had central/diffuse abdominal pain. The mean frequency of pain attacks was 4 to 9 times lower than in patients with functional or organic gastrointestinal RAP. Because of the inconstant occurrence of dysuria and hematuria, the location of pain in areas other than the flank, and the lack of calculi shown on imaging studies performed after pain attacks, the urologic origin of pain may be overlooked and ineffective procedures performed. The possibility of urolithiasis should be considered in children with RAP who have a family history of urolithiasis and/or infrequent pain attacks, even when dysuria and hematuria are lacking, and in younger children even when pain is not lateral.

  18. Short-segment transverse myelitis lesions in a cohort of Latin American patients with neuromyelitis optica spectrum disorders.

    PubMed

    Carnero Contentti, Edgar; Daccach Marques, Vanessa; Soto de Castillo, Ibis; Tkachuk, Verónica; Antunes Barreira, Amilton; Armas, Elizabeth; Chiganer, Edson; de Aquino Cruz, Camila; Di Pace, José Luis; Hryb, Javier Pablo; Lavigne Moreira, Carolina; Lessa, Carmen; Molina, Omaira; Perassolo, Mónica; Soto, Arnoldo; Caride, Alejandro

    2018-05-22

    Multicenter retrospective study. The aim was to determine the frequency and magnetic resonance imaging (MRI) features of short-segment transverse myelitis (STM) in patients with neuromyelitis optica spectrum disorders (NMOSD) during a myelitis attack. Latin American diagnostic centres (Neuroimmunology Unit). A multicenter study from Argentina, Brazil and Venezuela was performed. Seventy-six patients with NMOSD were included. We analyzed 346 attacks and reviewed spinal cord MRIs performed within 30 days from spinal attack onset. Sagittal and axial characteristics on cervical and thoracic MRI (1.5 tesla) were observed. Demographics, clinical, serological, and disability data were collected. Among the 76 patients with NMOSD, isolated STM was observed in 8% (n = 6), multisegmental lesions (longitudinally extensive transverse myelitis (LETM) + STM) in 28% (n = 21; 13 had at least one STM), LETM in 42% (n = 32), and normal spinal MRI in 22% (n = 17). However, isolated STM was increased by 10% in patients with NMOSD with spinal lesions (6 out of 59) with mean attacks of 2.5 (±0.83) and last follow-up expanded disability status scale (EDSS) of 3.1 (±2.63). Positive aquaporin 4 antibodies (AQP4-ab) were found in 50%. Upper-cervical lesion was most frequently observed (5 out of 6). Myelitis was preceded by ON in all isolated patients with STM. Only one had a positive gadolinium lesion and none of these had asymptomatic spinal cord lesion. Isolated STM does not exclude NMOSD diagnosis. Therefore, APQ4-ab testing could be useful during a myelitis attack with STM.

  19. Analysis of Wind Tunnel Lateral Oscillatory Data of the F-16XL Aircraft

    NASA Technical Reports Server (NTRS)

    Klein, Vladislav; Murphy, Patrick C.; Szyba, Nathan M.

    2004-01-01

    Static and dynamic wind tunnel tests were performed on an 18% scale model of the F-16XL aircraft. These tests were performed over a wide range of angles of attack and sideslip with oscillation amplitudes from 5 deg. to 30 deg. and reduced frequencies from 0.073 to 0.269. Harmonic analysis was used to estimate Fourier coefficients and in-phase and out-of-phase components. For frequency dependent data from rolling oscillations, a two-step regression method was used to obtain unsteady models (indicial functions), and derivatives due to sideslip angle, roll rate and yaw rate from in-phase and out-of-phase components. Frequency dependence was found for angles of attack between 20 deg. and 50 deg. Reduced values of coefficient of determination and increased values of fit error were found for angles of attack between 35 deg. and 45 deg. An attempt to estimate model parameters from yaw oscillations failed, probably due to the low number of test cases at different frequencies.

  20. An Adaptive Reputation-Based Algorithm for Grid Virtual Organization Formation

    NASA Astrophysics Data System (ADS)

    Cui, Yongrui; Li, Mingchu; Ren, Yizhi; Sakurai, Kouichi

    A novel adaptive reputation-based virtual organization formation is proposed. It restrains the bad performers effectively based on the consideration of the global experience of the evaluator and evaluates the direct trust relation between two grid nodes accurately by consulting the previous trust value rationally. It also consults and improves the reputation evaluation process in PathTrust model by taking account of the inter-organizational trust relationship and combines it with direct and recommended trust in a weighted way, which makes the algorithm more robust against collusion attacks. Additionally, the proposed algorithm considers the perspective of the VO creator and takes required VO services as one of the most important fine-grained evaluation criterion, which makes the algorithm more suitable for constructing VOs in grid environments that include autonomous organizations. Simulation results show that our algorithm restrains the bad performers and resists against fake transaction attacks and badmouth attacks effectively. It provides a clear advantage in the design of a VO infrastructure.

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