Deep learning : enhancing the security of software-defined networks

Software-defined networking (SDN) is a communication paradigm that promotes network flexibility and programmability by separating the control plane from the data plane. SDN consolidates the logic of network devices into a single entity known as the controller. SDN raises significant security challenges related to its architecture and associated characteristics such as programmability and centralisation. Notably, security flaws pose a risk to controller integrity, confidentiality and availability. The SDN model introduces separation of the forwarding and control planes. It detaches the control logic from switching and routing devices, forming a central plane or network controller that facilitates communications between applications and devices. The architecture enhances network resilience, simplifies management procedures and supports network policy enforcement. However, it is vulnerable to new attack vectors that can target the controller. Current security solutions rely on traditional measures such as firewalls or intrusion detection systems (IDS). An IDS can use two different approaches: signature-based or anomaly-based detection. The signature-based approach is incapable of detecting zero-day attacks, while anomaly-based detection has high false-positive and false-negative alarm rates. Inaccuracies related to false-positive attacks may have significant consequences, specifically from threats that target the controller. Thus, improving the accuracy of the IDS will enhance controller security and, subsequently, SDN security. A centralised network entity that controls the entire network is a primary target for intruders. The controller is located at a central point between the applications and the data plane and has two interfaces for plane communications, known as northbound and southbound, respectively. Communications between the controller, the application and data planes are prone to various types of attacks, such as eavesdropping and tampering. The controller software is vulnerable to attacks such as buffer and stack overflow, which enable remote code execution that can result in attackers taking control of the entire network. Additionally, traditional network attacks are more destructive. This thesis introduces a threat detection approach aimed at improving the accuracy and efficiency of the IDS, which is essential for controller security. To evaluate the effectiveness of the proposed framework, an empirical study of SDN controller security was conducted to identify, formalise and quantify security concerns related to SDN architecture. The study explored the threats related to SDN architecture, specifically threats originating from the existence of the control plane. The framework comprises two stages, involving the use of deep learning (DL) algorithms and clustering algorithms, respectively. DL algorithms were used to reduce the dimensionality of inputs, which were forwarded to clustering algorithms in the second stage. Features were compressed to a single value, simplifying and improving the performance of the clustering algorithm. Rather than using the output of the neural network, the framework presented a unique technique for dimensionality reduction that used a single value—reconstruction error—for the entire input record. The use of a DL algorithm in the pre-training stage contributed to solving the problem of dimensionality related to k-means clustering. Using unsupervised algorithms facilitated the discovery of new attacks. Further, this study compares generative energy-based models (restricted Boltzmann machines) with non-probabilistic models (autoencoders). The study implements TensorFlow in four scenarios. Simulation results were statistically analysed using a confusion matrix, which was evaluated and compared with similar related works. The proposed framework, which was adapted from existing similar approaches, resulted in promising outcomes and may provide a robust prospect for deployment in modern threat detection systems in SDN. The framework was implemented using TensorFlow and was benchmarked to the KDD99 dataset. Simulation results showed that the use of the DL algorithm to reduce dimensionality significantly improved detection accuracy and reduced false-positive and false-negative alarm rates. Extensive simulation studies on benchmark tasks demonstrated that the proposed framework consistently outperforms all competing approaches. This improvement is a further step towards the development of a reliable IDS to enhance the security of SDN controllers

Optimization of an off-grid PV/biogas hybrid energy system for electrification: A case study in a rural area in Egypt

The increasing demand for energy in remote or rural areas, coupled with the environmental benefits and cost-effectiveness of renewable energy sources, has led to a growing interest in off-grid energy systems. This paper proposes an optimized off-grid energy system to supply energy demand for a village and a desalination reverse osmosis water plant (RO) in Shalateen, Egypt, using a combination of photovoltaic (PV) and biomass technologies. To achieve minimizing Loss of Power Supply Probability (LPSP) and Total Net Present Cost (TNPC), two decision variables are optimized using the Harmony Search algorithm implemented in MATLAB. The reliability of a designed system is met by considering the LPSP concept. The proposed system utilizes PV system as the primary energy source to power the electrical loads, with a biomass plant serving as a backup to increase system reliability and cost-effectiveness. The Demand Side Management (DSM) strategy is applied to further enhance the system\u27s cost-effectiveness. Five scenarios are studied to investigate their impact on the optimal design, the obtained results indicate that using PV/biomass generation system with DSM and LPSP is more promising

Role of multi-detector computed tomography in the evaluation of pancreatic tumors

AbstractObjectiveThe purpose of this study was to determine the role of multidetector computed tomography (MDCT) in evaluation and prediction of pancreatic tumors resectability.Patients and methodsThe study included 20 patients who had pancreatic masses, 16 males and 4 females, and their age range was 30–70years with a mean age of 58.0years. All the patients underwent non-contrast and contrast enhanced Multi-slice CT using a 16-slice machine. The gold standard for diagnosis was histopathology and operative data.ResultsAdenocarcinoma as reported by pathological studies was found in 8 patients, cyst adenocarcinoma in one patient, infiltrative adenocarcinoma in 2 patients, intraductal papillary mucinous tumor in 2 patients, mucinous cyst adenocarcinoma in one patient, pancreatic pseudo cyst in 2 patients and mucinous cystadenoma in 4 patients. According to MDCT criteria 6 patients were considered suitable for tumor resection and 14 patients were considered inoperable with unresectable tumor, one out of the 6 operable patients was unresectable during operation due to the invasion of the superior mesenteric vein with infiltration of the mesenteric root.ConclusionContrast-enhanced multiphase pancreatic imaging by multislice computerized tomography (MSCT) with its postprocessing techniques represents the image of choice for diagnosis and predicting pancreatic masses and resectability

Improved bioavailability of timolol maleate via transdermal transfersomal gel: Statistical optimization, characterization, and pharmacokinetic assessment

AbstractTimolol maleate (TiM), a nonselective β-adrenergic blocker, is a potent highly effective agent for management of hypertension. The drug suffers from extensive first pass effect, resulting in a reduction of oral bioavailability (F%) to 50% and a short elimination half-life of 4h; parameters necessitating its frequent administration. The current study was therefore, designed to formulate and optimize the transfersomal TiM gel for transdermal delivery. TiM loaded transfersomal gel was optimized using two 23 full factorial designs; where the effects of egg phosphatidyl choline (PC): surfactant (SAA) molar ratio, solvent volumetric ratio, and the drug amount were evaluated. The formulation variables; including particle size, drug entrapment efficiency (%EE), and release rate were characterized. The optimized transfersomal gel was prepared with 4.65:1 PC:SAA molar ratio, 3:1 solvent volumetric ratio, and 13mg drug amount with particle size of 2.722μm, %EE of 39.96%, and a release rate of 134.49μg/cm2/h. The permeation rate of the optimized formulation through the rat skin was excellent (151.53μg/cm2/h) and showed four times increase in relative bioavailability with prolonged plasma profile up to 72h compared with oral aqueous solution. In conclusion, a potential transfersomal transdermal system was successfully developed and the factorial design was found to be a smart tool, when optimized

A miniaturized triple-band and dual-polarized monopole antenna based on a CSRR perturbed ground plane

This paper proposes a new triple-band monopole antenna based on Complementary Split Ring Resonators (CSRR) perturbing the ground plane (GND). The antenna consists of an inverted-L-shaped monopole fed by a modified microstrip line with two CSRRs cut out of the ground plane. The operational bands are independently controlled by the CSRR unit cell parameters. In addition, the antenna presents a dual-polarization performance (vertical polarization at 2.4 GHz band and horizontal polarization at both 3.6 and 5.9 GHz bands). The designed antenna is fully planar and low profile avoiding the vias with the ground plane and covering the WLAN, WiMAX, and IEEE 801.11p bands at 2.45, 3.6, and 5.8 GHz. A compact prototype ( 0.32λ0×0.32λ0 being λ0 is the wavelength corresponding to the lowest resonance frequency) has been fabricated and measured showing good agreement between simulations and measurements. The measured impedance bandwidths are 10% (2.38-2.63 GHz), 2.5% (3.54-3.63 GHz), and 20% (5.83-7.12 GHz) whereas the measured gains are 1.34, 0.68, and 2.65 dBi at 2.4, 3.6, and 5.9 GHz respectively.This work was supported by PID2019-109984RB-C41

GEOCHEMISTRY, URANIUM, THORIUM AND RARE EARTH ELEMENTS OF TRACHYTE DYKES OF UMM SALATIT MOUNTAIN AREA, CENTRAL EASTERN DESERT, EGYPT

Umm Salatit Mountain area is a part of the Central Eastern Desert of Egypt. It is composed of ophiolitic mélange, older granitoids, biotite granites, muscovite granites and post granitic dykes and veins. Purpose of the work. The present work deals with the detailed investigations of the geology, petrography, geochemistry and spectrometric prospecting of the studied trachyte dykes as a possible source of uranium mineralization. Research methods. This work involves both field work (Construction of geological map with the structural features, scale 1 : 50,000, Spectrometric measurements of the different rock units using a portable gamma-ray spectrometer RS-230) and laboratory work (preparation of thin sections for petrographic studies by polarizing microscope), Atomic Emission Spectroscopy (AES), and Mass-Spectrometer with Inductively Coupled Plasma (ICPMS). Results. Petrographically, trachyte dykes consist mainly of K-feldspar with relatively minor amount of plagioclase, iron oxides, quartz and biotite. Secondary minerals are represented by sericite, muscovite, chlorite, carbonates and epidote. Accessory minerals are represented by opaque minerals. Trachytic textures are the main characteristic feature in trachyte. Geochemically, the investigated trachyte dykes were originated from an alkali magmarich in total alkalis, and the tectonic setting is continental basalt. Trachyte dykes have steep LREEs, nearly flat HREEs and a negative Eu anomaly. The negative Eu anomaly is either due to the partitioning of Eu into feldspar during fractionation, which is an important process in developing alkalinity, or the presence of residual feldspar in the source. Another alternative explanation for the negative Eu anomaly is based on the high oxygen fugacity in the melt due to volatile saturation. In general, all trachyte samples show moderate enrichment of most large ion lithophile elements (LILE) and high field strength elements (HFSE) and depletion of P, Ti and K. The depletion of Ti and p is ascribed to fractionation of titanomagnetite and apatite. The determination of equivalent uranium, thorium (ppm), potassium % and dose rate (m Sv/y) radiometrically by using portable RS-230 indicates that the dose rate in the trachyte dykes ranges from 0.5 to 1.5 with an average of 1.2 (m Sv/y). The radiometric data of the radioelements for them show a wide variation in eU and eTh contents. The eU content ranges from 2 to 14 ppm with an average of 6.6 ppm and the eTh content ranges from 4 to 37 ppm with an average of 18.03 ppm. Both U and Th correlate similarly with other major and trace elements, reflecting their geochemical coherence during the crystallization of the magma

Sero-molecular Epidemiology of Hepatitis E Virus in Blood Donors, Gezira State, Sudan: A Cross-sectional Study

Background: Hepatitis E virus (HEV) is a hepatotropic pathogen that causes significant morbidity and mortality in humans. It is an important causative agent of viral hepatitis outbreaks. This study investigates the serological and molecular prevalence of HEV in blood donors attending the Central Blood Bank in Wad Medani City in Gezira State, Sudan. Methods: The study adopted a cross-sectional descriptive design. A structured questionnaire was used to collect data concerning demographic information and risk factors associated with HEV transmission. All enrolled participants (N = 300) were screened for HEV IgG antibodies using commercial ELISA kits, then strong positive samples (N = 84) were selected and rescreened for HEV IgM and HEV RNA by RT PCR. SPSS version 24.0 was used for analysis. Results: Out of 300 male participants, 36.3% (109/300) were positive for HEV IgG. However, only one participant was IgM positive, while the HEV RNA was negative. The highest prevalence rates of the virus were 42 (44.6%) among the age group of 31–40 years, 20 (48.8%) in those who consumed food from outside, 13 (50%) in three to four multiple blood donations, and 5 (62.5%) in those who consumed water from the river source. A significant association of HEV IgG prevalence concerning the occupation of the participants being students or farmers was detected using univariate and multivariate analysis (P-value = 0.007). Conclusion: High prevalence of HEV IgG was demonstrated among the healthy blood donors in this study. Given the possibility of HEV transmission by transfusion from donors to recipients, we recommend that routine screening for HEV should be adopted by blood banks in Sudan

The role of liver in leptin metabolism in experimental nephrotic syndrome

Leptin is a hormone influencing food intake, energy expenditure and body weight. It is pro-duced by adipocytes, exerts its effects on brain, endocrine pancreas and other organs by acti-vating trans-membrane receptors and is cleared from plasma mainly by the kidneys. Several studies have suggested that leptin's effects on metabolism are mediated by the liver. Our aim was to evaluate the role of the liver in the metabolism of leptin by comparing the serum leptin level in the portal vein with that in inferior vena cava and to study the relationship between leptin and lipoprotein levels in healthy and nephrotic rats. Experimental nephrotic syndrome was conducted in rats by intraperitoneal injection of the supernatant from the kidney suspen-sion obtained by previous unilateral nephrectomy of the same rat and complete Freund's adju-vant. There was a highly significant rise in leptin and lipid profile levels in the nephrotic rats compared with the normal rats. A highly significant increase in leptin in the inferior vena cava was detected compared with the level in the portal veins of nephrotic rats, while insignificant difference was observed in normal rats. This work has stressed the role of liver in leptin and lipid metabolism in nephrotic rats

Impact of Sever Plasmodium falciparum infection on Platelets Parameters among Sudanese children Living in Al-Jazira State

Background: Falciparum malaria remains one of the most global infection among children particularly in communities with poor resources. Falciparum malaria associated with several hematological changes that affect the major blood cell lines such as platelets lead to platelets parameters (platelets count and indices) abnormalities. Objectives: The aim of this study was to evaluate the effects of falciparum malaria on platelets parameters (platelets count and indices) among Sudanese children. In addition to study relationships and correlation between platelets parameters and malaria parasitemia and parasite count. Materials and Methods: A case control study was conducted in Wad Medani Pediatric Hospital in collaboration with Faculty of Medical laboratory Sciences, University of Gezira, Sudan among 100 children with severe falciparum malaria (mean age 8.63 ± 3.40 years; 61% males), 100 children with uncomplicated falciparum malaria (mean age 8.83 ± 4.20 years; 45% males) and 100 children with normal healthy children controls (mean age 10.08 ± 3.58 years; 50% males). Parasitemia and parasite count (%) was determined directly from thick and thin blood films respectively. The platelets parameters (platelets count and indices) measured by using Sysmex XP 300 N automated analyzer, and platelets count was confirmed and assessed using stained thin blood film. SPSS software (V 20.0) and Stat disk software (V 13.0) were used for data analysis. Results: 72 % of severe falciparum malaria (SM) have hyperparasitemia, while 18 % among uncomplicated falciparum malaria (UM). The thrombocytopenia account for 43 % (SM: 30.5 %; UM: 12.5 %), low PCT account for 35.5 % (SM: 27 %; UM: 8.5 %) and high PDW account for 46.5 % (SM: 23.5 %; UM: 23 %) in falciparum malaria cases. The mean PLTs count and PDW were statistically significantly differences between falciparum malaria cases and normal healthy control (P value 0.000 and 0.008 respectively). The mean PLTs count and PCT in severe falciparum malaria cases were lower than uncomplicated falciparum malaria cases (P value 0.005 and 0.000 respectively). The PLTs count and PCT had significant negative correlation within malaria parasitemia (P value 0.000; r -0.286; P value 0.004; r -0.205 respectively) and malaria parasite count (P value 0.000; r -0.450; P value 0.000; r -0.270 respectively). Conclusion: The study concluded that thrombocytopenia, low PCT and high PDW were observed as most platelets parameters changes in falciparum malaria. PLTs count along with PCT to be recommended as hematological diagnostic markers and prognostic tool to assess the disease severity and to improve the management of falciparum malaria among patients