318 research outputs found
Toward Smart Moving Target Defense for Linux Container Resiliency
This paper presents ESCAPE, an informed moving target defense mechanism for
cloud containers. ESCAPE models the interaction between attackers and their
target containers as a "predator searching for a prey" search game. Live
migration of Linux-containers (prey) is used to avoid attacks (predator) and
failures. The entire process is guided by a novel host-based
behavior-monitoring system that seamlessly monitors containers for indications
of intrusions and attacks. To evaluate ESCAPE effectiveness, we simulated the
attack avoidance process based on a mathematical model mimicking the
prey-vs-predator search game. Simulation results show high container survival
probabilities with minimal added overhead.Comment: Published version is available on IEEE Xplore at
http://ieeexplore.ieee.org/document/779685
EHV-1 Pathogenesis: Current in vitro Models and Future Perspectives
Primary infection and pathogenesis of equine herpesvirus type 1 (EHV-1) require an intricate interaction of virus with the mucosal epithelium, mononuclear cells and the vascular endothelium. Studies on EHV-1 have been facilitated by the development of different in vitro models that recapitulate the in vivo tissue complexity. The available in vitro assays can be categorized into (i) models mimicking the epithelium-peripheral blood mononuclear cell (PBMC) interaction, which include ex vivo mucosal (nasal and vaginal) explants and equine respiratory epithelial cells (EREC) cultures; and (ii) PBMC-endothelium mimicking models, including flow chamber and contact assays. These in vitro models have proven their worth in attempts to recapitulate the in vivo architecture and complexity, produce data relevant to natural host infection, and reduce animal use due to in vivo experiments. Although horse models are still needed for certain experiments, e.g., EHV-1 myeloencephalopathy or vaccination studies, available in vitro models can be used to obtain highly valuable data on virus-host tissue interactions. Microfluidic based 3D culture system (e.g., horse-on-a-chip) could be a potential upgraded version of these in vitro models for future research
MystifY : A Proactive Moving-Target Defense for a Resilient SDN Controller in Software Defined CPS
The recent devastating mission CyberâPhysical System (CPS) attacks, failures, and the desperate need to scale and to dynamically adapt to changes, revolutionized traditional CPS to what we name as Software Defined CPS (SD-CPS). SD-CPS embraces the concept of Software Defined (SD) everything where CPS infrastructure is more elastic, dynamically adaptable and online-programmable. However, in SD-CPS, the threat became more immanent, as the long-been physically-protected assets are now programmatically accessible to cyber attackers. In SD-CPSs, a network failure hinders the entire functionality of the system. In this paper, we present MystifY, a spatiotemporal runtime diversification for Moving-Target Defense (MTD) to secure the SD-CPS infrastructure. In this paper, we relied on Smart Grid networks as crucial SD-CPS application to evaluate our presented solution. MystifYâs MTD relies on a set of pillars to ensure the SDN controller resiliency against failures and attacks. The 1st pillar is a grid-aware algorithm that optimally allocates the most suitable controllerâdeployment location in large-scale grids. The 2nd pillar is a special diversifier that dynamically relocates the controller between heterogeneously configured hosts to avoid host-based attacks. The 3rd pillar is a temporal diversifier that dynamically detours controllerâworkload between multiple controllers to enhance their reliability and to detect and avoid controller intrusions. Our experimental results showed the efficiency and effectiveness of the presented approach
Optimal tuning of fractional order controllers for dual active bridge-based DC microgrid including voltage stability assessment
In this article, three evolutionary search algorithms: particle swarm optimization (PSO), simulated annealing (SA) and genetic algorithms (GA), have been employed to determine the optimal parameter values of the fractional-order (FO)-PI controllers implemented in the dual active bridge-based (DAB) DC microgrid. The optimum strategy to obtain the parameters of these FO-PI controllers is still a major challenge for many power systems applications. The FO-PI controllers implemented in the DAB are used to control the DC link voltage to the desired value and limit the current flowing through the converter. Accordingly, the investigated control system has six parameters to be tuned simultaneously; Kp1, Ki1, Âż1 for FO-PI voltage controller and Kp2, Ki2, Âż2 for FO-PI current controller. Crucially, this tuning optimization process has been developed to enhance the voltage stability of a DC microgrid. By observing the frequency-domain analysis of the closed-loop and the results of the subsequent time-domain simulations, it has been demonstrated that the evolutionary algorithms have provided optimal controller gains, which ensures the voltage stability of the DC microgrid. The main contribution of the article can be considered in the successful application of evolutionary search algorithms to tune the parameters of FO-based dual loop controllers of a DC microgrid scheme whose power conditioner is a DAB topology.Peer ReviewedPostprint (published version
Equid Herpesvirus-1 Exploits the Extracellular Matrix of Mononuclear Cells to Ensure Transport to Target Cells
Mononuclear cells are the first line of defense against microbial infection. Yet, several viruses have evolved different mechanisms to overcome host defenses to ensure their spread. Here, we show unique mechanisms of how equid herpesvirus-1 manipulates peripheral blood mononuclear cells (PBMC) to travel further in the body. (1) "PBMC-hitching": at the initial contact, herpesviruses lurk in the extracellular matrix (ECM) of PBMC without entering the cells. The virus exploits the components of the ECM to bind, transport, and then egress to infect other cells. (2) "Intracellular delivery": transendothelialmigration is a physiological mechanism where mononuclear cells can transmigrate through the endothelial cells. The virus was intangible and probably did not interfere with such a mechanism where the infected PBMC can probably deliver the virus inside the endothelium. (3) "Classical-fusion": this process is well mastered by herpesviruses due to a set of envelope glycoproteins that facilitate cell-cell fusion and virus spread
Micellar high performance liquid chromatographic determination of tinidazole in combination with ciprofloxacin or norfloxacin in bulk, pharmaceutical dosage forms and in spiked human plasma
A micellar liquid chromatographic method was developed for determination of tinidazole in bulk, dosage forms and human plasma using intersil cyano column and a mobile phase of 0.1 M sodium dodecyl sulphate, 20% 1-propanol, 0.3% triethylamine in 0.02 M orthophosphoric acid:water (60:40, v:v) (pH = 4). The U.V. detection was achieved at 311 nm. Various chromatographic parameters were investigated to select the optimum conditions for the separation, e.g. types of columns, pH of mobile phase, concentration of sodium dodecyl sulphate, 1-propanol, triethylamine, etc. The method was linear over the concentration range 40-200 ”g/mL with regression coefficient 0.999. The result obtained by the proposed method was compared with that obtained by the reference HPLC technique. Furthermore, the proposed method was successfully applied as stability-indicating method for determination of tinidazole under different stressed conditions. The method showed good selectivity, repeatability, linearity and sensitivity according to the evaluation of the validation parameters
UM ESTUDO EDUCACIONAL SOBRE O EFEITO DA ANSIEDADE FUTURA NO PROGRESSO ACADĂMICO DE ESTUDANTES UNIVERSITĂRIOS : (ALUNOS DA UNIVERSIDADE PRĂNCIPE SETAM BIN ABDULAZIZ)
The aim of this study was to An educational study of the effect of future anxiety on the academic progress of university students. Generally, Future anxiety means the score that a student obtains on the Future Anxiety Scale. This study aims at identifying the level of future anxiety among the students of Prince Sattam Bin Abdul-Aziz University. It attempts to highlight the differences between them in light of variable according to gender. It also seeks to underscore the impact of future anxiety on their academic achievement and the reasons for this anxiety and the suggested treatment. To achieve this goal, the researcher uses the descriptive analytical method to collect and analyze the data. The study is conducted on a sample of (60) male and female students in the academic year (2022/2023). The study sample was selected using stratified random sampling.O objetivo deste estudo foi realizar um estudo educacional sobre o efeito da ansiedade futura no progresso acadĂȘmico de estudantes universitĂĄrios. Geralmente, Ansiedade futura significa a pontuação que um aluno obtĂ©m na Escala de Ansiedade Futura. Este estudo tem como objetivo identificar o nĂvel de ansiedade futura entre os alunos da Universidade PrĂncipe Sattam Bin Abdul-Aziz. Tenta destacar as diferenças entre eles Ă luz das variĂĄveis de acordo com o gĂȘnero. Procura tambĂ©m sublinhar o impacto da ansiedade futura no seu desempenho acadĂ©mico e as razĂ”es dessa ansiedade e o tratamento sugerido. Para atingir esse objetivo, o pesquisador utiliza o mĂ©todo analĂtico descritivo para coletar e analisar os dados. O estudo Ă© realizado numa amostra de (60) estudantes do sexo masculino e feminino no ano letivo (2022/2023). A amostra do estudo foi selecionada por meio de amostragem aleatĂłria estratificada
Safety of Endoscopic Retrograde Cholangiopancreatography (ERCP) in Pregnancy: A Systematic Review and Meta-Analysis
Background/Aims: Endoscopic retrograde cholangiopancreatography (ERCP) is a technically challenging procedure rarely associated with severe postprocedure complications. Hormonal changes during pregnancy promote cholelithiasis, but there are limited clinical data available on the outcomes of ERCP in pregnant women. ERCP techniques without irradiation were recently introduced as potential alternative. We performed a systematic review and meta-analysis to assess the safety of ERCP in pregnancy and to compare outcomes of radiation versus nonradiation ERCP. Materials and Methods: A systematic search of PubMed, Medline/Ovid, Web of Science, and Google Scholar through April 18th, 2018 using PRISMA and MOOSE guidelines identified 27 studies reporting the outcomes of ERCP in pregnancy. Random effects pooled event rate and 95% confidence intervals (CIs) were estimated. Heterogeneity was measured by I2, and meta-regression analysis was conducted. Adverse outcomes were divided into fetal, maternal pregnancy-related, and maternal nonpregnancy-related. Results: In all, 27 studies reporting on 1,307 pregnant patients who underwent ERCP were identified. Median age was 27.1 years. All results were statistically significant (P...) (See full abstract in article)
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