BotCap: Machine Learning Approach for Botnet Detection Based on Statistical Features

In this paper, we describe a detailed approach to develop a botnet detection system using machine learning (ML)techniques. Detecting botnet member hosts, or identifying botnet traffic has been the main subject of manyresearch efforts. This research aims to overcome two serious limitations of current botnet detection systems:First, the need for Deep Packet Inspection-DPI and the need to collect traffic from several infected hosts. Toachieve that, we have analyzed several botware samples of known botnets. Based on this analysis, we haveidentified a set of statistical features that may help to distinguish between benign and botnet malicious traffic.Then, we have carried several machine learning experiments in order to test the suitability of ML techniques andalso to pick a minimal subset of the identified features that provide best detection. We have implemented ourapproach in a tool called BotCap whose test results showed its proven ability to detect individually infected hostsin a local network

Modelling Multilayer Communication Channel in Terahertz Band for Medical Applications

In this work we present a multi-layer channel model for terahertz communication that incorporates both layers of human body tissues and textile layers. Many research works tackled communication channel modelling in human body alone while some other research focused on textile characterization/modelling alone. There is a real gap in connecting these different models. To investigate this, a multi-layer channel model for terahertz communication is developed, this model assumes external textile layer stacked over layers of human body tissues. The electromagnetic properties of the different layers are extracted from previous works that used time domain spectroscopy (TDS) in the terahertz band to characterize each of the considered layers. The model is implemented as a flexible MATLAB/Octave program that enables the simulation of layers with either fixed or random depths. This paper aims to pave the way to connecting patients’ in-body nano-nodes with off-body (on-cloth) nano-nodes by building such a combined channel model. This helps in many applications especially in the medical field. For example, having connected nano-nodes can help in diagnosing diseases, monitoring health by sending information to the external environment, treatment (e.g., increasing or decreasing a certain dose depending on the monitoring), etc. The obtained results show how the THz signal can be affected when it propagates through heterogeneous mediums (i.e., human body tissues and textile). Various types of path-loss has been calculated for this purpose and verified by comparison with results from previous research on separate models of human body and textile

Nickel challenge up regulates CD69 expression on T lymphocyte sub-sets from patients with nickel induced contact dermatitis

Background: Persistent antigenic stimulation due to repeated exposure to nickel may lead to chronic inflammation resulting in allergic contact dermatitis (ACD).Objectives: This study was performed to assess nickel induced immune activation among patients sensitized against nickel.Patients and Methods: A total of 35 patients (29 females and 6 males; mean age 36±9 years) with nickel contact dermatitis and 20 patch test negative healthy individuals  (14 females and 6 males; mean age 29±7 years) were included in this study. Peripheral blood of patients and controls was incubated with nickel sulfate for 24 hours. Immune activation was assessed by CD69 up-reg- ulation on T lymphocyte sub-sets by flow cytometry.Results: Base line expression of CD69 on CD8+ lymphocytes was higher among patients compared to controls (4.1±1.3%vs2.8±1.1%;p<0.009). There was no difference in proportions of CD±CD69+ cells between patients and controls (3.2±0.9%vs2.3±0.8%). Exposure to nickel induced expression of CD69 on a significantly higher proportion of CD4+ lympho- cytes (22.1±6.2%) of the ACD patients compared to controls (2.8±2.5%;p<0.0001). Similarly nickel induced CD69 expression on a higher proportion of CD8+ lymphocytes (18.2±5.3%) from ACD patients compared to the controls (1.9±1.8%;p<0.0006).Conclusion: CD69 molecule appears to be an important regulator of immune response in nickel contact dermatitis.   Keywords: Nickel, CD4+, CD8+, CD69, contact dermatitis

Nickel challenge up regulates CD69 expression on T lymphocyte sub-sets from patients with nickel induced contact dermatitis

Background: Persistent antigenic stimulation due to repeated exposure to nickel may lead to chronic inflammation resulting in allergic contact dermatitis (ACD). Objectives: This study was performed to assess nickel induced immune activation among patients sensitized against nickel. Patients and Methods: A total of 35 patients (29 females and 6 males; mean age 36\ub19 years) with nickel contact dermatitis and 20 patch test negative healthy individuals (14 females and 6 males; mean age 29\ub17 years) were included in this study. Peripheral blood of patients and controls was incubated with nickel sulfate for 24 hours. Immune activation was assessed by CD69 up-regulation on T lymphocyte sub-sets by flow cytometry. Results: Base line expression of CD69 on CD8+ lymphocytes was higher among patients compared to controls (4.1\ub11.3%vs2.8\ub11.1%;p<0.009). There was no difference in proportions of CD\ub1CD69+ cells between patients and controls (3.2\ub10.9%vs2.3\ub10.8%). Exposure to nickel induced expression of CD69 on a significantly higher proportion of CD4+ lymphocytes (22.1\ub16.2%) of the ACD patients compared to controls (2.8\ub12.5%;p<0.0001). Similarly nickel induced CD69 expression on a higher proportion of CD8+ lymphocytes (18.2\ub15.3%) from ACD patients compared to the controls (1.9\ub11.8%;p<0.0006). Conclusion: CD69 molecule appears to be an important regulator of immune response in nickel contact dermatitis. DOI: https://dx.doi.org/10.4314/ahs.v19i1.19 Cite as: Zahid S, Mustafa A, Dina A, Sawsan B, Felwa A, Mohammed G, et al. Nickel challenge up regulates CD69 expression on T lymphocyte sub-sets from patients with nickel induced contact dermatitis. Afri Health Sci. 2019;19(1). 1460-1466. https://dx.doi. org/10.4314/ahs.v19i1.1

Évaluation des systèmes de détection d'intrusion

TOULOUSE3-BU Sciences (315552104) / SudocSudocFranceF

Arabic COVID-19 Psychological Distress Scale: Development and initial validation

Objective: To develop a psychometrically reliable instrument to assess psychological distress during the COVID-19 pandemic across Arab countries. Design: The new instrument was developed through the review of relevant literature. We adapted multiple items from the following tools: The Fear of COVID-19 Scale, Social Phobia Inventory, Health Anxiety Inventory, Swine Influenza Anxiety Scale and the Arabic Scale of Death Anxiety to design our new assessment tool which is called COVID-19 Psychological Distress Scale (CPDS). For psychometric analyses and validation, we conducted a cross-sectional study that solicited data through a web-based survey using the newly developed CPDS. Setting and participants: This validation study was conducted in four Arab countries, including Algeria, Kuwait, Saudi Arabia and Yemen. A total of 1337 participants from these countries have voluntarily responded to our survey questionnaire that included the newly developed scale. Results: The final version of the CPDS comprised 12 items. Participants from Algeria (n=447), Kuwait (n=437), Saudi Arabia (n=160) and Yemen (n=293) have completed the 12-item CPDS. Exploratory factor analysis (used on the Algerian sample) suggested a two-factor structure of the CPDS. The two-factor structure was then supported by the confirmatory factor analysis with an independent sample. Additionally, Rasch analyses showed that all the items fit well in their embedded construct; only one item showed somewhat substantial differential item functioning across gender and country. Conclusion: The 12-item CPDS was found to be measurement invariant across country and gender. The CPDS, with its promising psychometric properties, might help healthcare professionals to identify people with COVID-19-induced psychological distress