Packet filter performance monitor (anti-DDOS algorithm for hybrid topologies)

DDoS attacks are increasingly becoming a major problem. According to Arbor Networks, the largest DDoS attack reported by a respondent in 2015 was 500 Gbps. Hacker News stated that the largest DDoS attack as of March 2016 was over 600 Gbps, and the attack targeted the entire BBC website. With this increasing frequency and threat, and the average DDoS attack duration at about 16 hours, we know for certain that DDoS attacks will not be going away anytime soon. Commercial companies are not effectively providing mitigation techniques against these attacks, considering that major corporations face the same challenges. Current security appliances are not strong enough to handle the overwhelming traffic that accompanies current DDoS attacks. There is also a limited research on solutions to mitigate DDoS attacks. Therefore, there is a need for a means of mitigating DDoS attacks in order to minimize downtime. One possible solution is for organizations to implement their own architectures that are meant to mitigate DDoS attacks. In this dissertation, we present and implement an architecture that utilizes an activity monitor to change the states of firewalls based on their performance in a hybrid network. Both firewalls are connected inline. The monitor is mirrored to monitor the firewall states. The monitor reroutes traffic when one of the firewalls become overwhelmed due to a HTTP DDoS flooding attack. The monitor connects to the API of both firewalls. The communication between the rewalls and monitor is encrypted using AES, based on PyCrypto Python implementation. This dissertation is structured in three parts. The first found the weakness of the hardware firewall and determined its threshold based on spike and endurance tests. This was achieved by flooding the hardware firewall with HTTP packets until the firewall became overwhelmed and unresponsive. The second part implements the same test as the first, but targeted towards the virtual firewall. The same parameters, test factors, and determinants were used; however a different load tester was utilized. The final part was the implementation and design of the firewall performance monitor. The main goal of the dissertation is to minimize downtime when network firewalls are overwhelmed as a result of a DDoS attack

A Federated Architecture for Heuristics Packet Filtering in Cloud Networks

The rapid expansion in networking has provided tremendous opportunities to access an unparalleled amount of information. Everyone connects to a network to gain access and to share this information. However when someone connects to a public network, his private network and information becomes vulnerable to hackers and all kinds of security threats. Today, all networks needs to be secured, and one of the best security policies is firewall implementation. Firewalls can be hardware or cloud based. Hardware based firewalls offer the advantage of faster response time, whereas cloud based firewalls are more flexible. In reality the best form of firewall protection is the combination of both hardware and cloud firewall. In this thesis, we implemented and configured a federated architecture using both firewalls, the Cisco ASA 5510 and Vyatta VC6.6 Cloud Based Firewall. Performance evaluation of both firewalls were conducted and analyzed based on two scenarios; spike and endurance test. Throughputs were also compared, along with some mathematical calculations using statistics. Different forms of packets were sent using a specialized tool designed for load testing known as JMeter. After collecting the results and analyzing it thoroughly, this thesis is concluded by presenting a heuristics method on how packet filtering would fall back to the cloud based firewall when the hardware based firewall becomes stressed and over loaded, thus allowing efficient packet flow and optimized performance. The result of this thesis can be used by Information Security Analyst, students, organizations and IT experts to have an idea on how to implement a secured network architecture to protect digital information

Nutrient and Anti-Nutritional Composition of Jam Prepared from Pineapple Ananas Comosus

An investigation was conducted to evaluate the nutrient and anti-nutritional composition of jam prepared from Pineapple (Ananas comosus). The result of the proximate analysis indicated that processing caused a reduction in the moisture (30.0 + 0.08) protein content (0.8 + 0.008). However, processing  pineapple to jam caused an increase in the crude lipid (3.4 + 0.26), Carbohydrate (58.6 + 0.30), Ash content (5.0 + 0.8) and crude fibre (2.2 + 0.08). The result obtained for the anti-nutritional factors showed that processing caused a reduction in phytate content (0.67 + 0.004), Tannin (0.19 + 0.004) and Oxalate (8.64 + 0.008). Keywords: Ananas comosus, Processing, Jam, Tannin, Crude Fat, Oxalate

Isolation and Estimation of DNA Level in Coconut Leaf (Coccos Nucifera)

The DNA Level of Coconut leaf was determined using agarose gel electrophoresis and UV-double beam spectrophotometer. 30?g leaf sample was weighed; chemical homogenization using mortar and pestle was done using lyses buffer and “Morning fresh” detergent. Whole sample was centrifuged at 10,000 rpm for 20 minutes; the supernatant was decamped into clean microcentruifuge tubes. Ethanol (500ml) was added and mixed thoroughly and incubated at room temperature for 30 minutes. DNA is insoluble in ethanol and so will appear as white precipitate at the bottom of the tube. Sample was centrifuged at 10,000 rpm for 5 minutes, thereafter the content was exposed to the atmosphere for 10 minutes to rid off remaining solvent (Ethanol). The pellets were dissolved in 50ml of TE (Tris-EDTA) buffer. The DNA (25ml) was taken and diluted in 1.75ml of TE Buffer and absorbance read at 260nm and 280nm with purity of DNA calculated followed by Electrophoresis. 25ml of the DNA sample was taken and ran on 0.8% agarose gel electrophoresis using a standard marker for 60 minutes. The analysis was done in triplicate with the ratio of absorbance at 260 and 280nm (1.79, 1.76 and 1.84) showing the purity of the DNA sample. Keywords: Coccos nucifera, Percentage Purity, DNA Sample, TE Buffer, Agarose Gel Electrophoresis

Assessment of regulation compliance and quality of sachet water factories In Ibadan North Local Government, Oyo State, Nigeria

Provision of clean drinking water is one of the basic human necessities for healthy livelihood. In Nigeria, many people relied on sachet waters as an alternative source of clean drinking water. However, complaints abound regarding lack of proper water quality standard being used which is a major health concern. This study assessed the regulatory compliance of some sachet water production companies and water quality standard in Ibadan North Local Government Area, Oyo State, Nigeria. Questionnaires were administered on factory’s organisational structure and staffing; facilities and equipment; water treatment processes and sanitation practices, Also, Sachet water samples were analysed for the contaminants of Turbidity, Colour, Odour, pH, Nitrate, Chloride, Iron, Electrical conductivity and E-coli count. From the questionnaire analysis, the adherence level with the regulations was poor as majority (60%) of the sachet water factories have poor organisational structure and only 33% have adequate facilities and equipment. However, water quality analysis showed that most of the sachet water parameters tested were within the standard range except for pH values and E Coli count which majority (70%) falls below standard for both. The study concludes that most sachet water brands produced are unsafe for human consumption. There is need for proper monitoring by relevant agencies towards ensuring sachet water factories continuously complied with standard operations for better public health in the study area

Effect of Imbibition Time on Hormonal Changes of Germinating Tamarindus indica and Prosopis juliflora

Imbibition time and hormonal changes play a significant role in seed germination. This study, evaluated the effects of some phytohormones; indole acetic acid (IAA), abscisic acid (ABA), gibberellin and cytokinins) and imbibition time (0, 48 and 96 hours) on Tamarindus indica and Prosopis juliflora. High-Performance Liquid Chromatography (HPLC) was used to determine the concentrations of the hormones. Results indicated significantly higher and faster in P. juliflora than T. indica. The germination rate was 4.1 - 68.1% and 4.0 - 61.4%, and model for inhibition time 28.256ln(x) and 25.791ln(x), respectively. Similarly, results also expressed highly significant variable changes in the concentrations of the four studied phytohormones between T. indica (0.491 - 0.705 mg/ml) and P. Juliflora (0.109 - 1.130 mg/ml). The concentrations of IAA and ABA were significantly higher by 60.6% and 77.7% in the seeds of T. indica than P. juliflora, respectively. P. juliflora had 37.6% and 12.5% higher cytokinin and gibberellin than T. indica, respectively. Cytokinin (0.7951 - 1.0939 mg/ml), gibberellins (0.535 - 0.757 mg/ml), IAA (0.363 - 0.419 mg/ml) and ABA (0.250 - 0.335 mg/ml) also varied significantly over the periods. In general, cytokinin and gibberellins increased by 8.1 - 27.3% and 22.9 - 23.0%, while that of IAA and ABA decreased 13.6 - 15.4% and 26.4 - 34.0%, over the imbibitions time of 0-96 hours. In conclusion, higher germination of P. juliflora is attributed to cytokinin and gibberellins, and the lower germination in T. indica to the higher inhibitory effects of IAA and ABA

Clausenidin from Clausena excavata induces apoptosis in hepG2 cells via the mitochondrial pathway

Ethnopharmacological relevance: Clausena excavata Burm.f. is used locally in folk medicine for the treatment of cancer in South East Asia. Aim of the study: To determine the mechanism of action of pure clausenidin crystals in the induction of hepatocellular carcinoma (hepG2) cells apoptosis. Materials and methods: Pure clausenidin was isolated from Clausena excavata Burm.f. and characterized using 1H and 13C NMR spectra. Clausenidin-induced cytotoxicity was determined by MTT assay. The morphology of hepG2 after treatment with clausenidin was determined by fluorescence and Scanning Electron Microscopy. The effect of clausenidin on the apoptotic genes and proteins were determined by real-time qPCR and protein array profiling, respectively. The involvement of the mitochondria in clausenidin-induced apoptosis was investigated using MMP, caspase 3 and 9 assays. Results: Clausenidin induced significant (p<0.05) and dose-dependent apoptosis of hepG2 cells. Cell cycle assay showed that clausenidin induced a G2/M phase arrest, caused mitochondrial membrane depolarization and significantly (p<0.05) increased expression of caspases 3 and 9, which suggest the involvement of the mitochondria in the apoptotic signals. In addition, clausenidin caused decreased expression of the anti-apoptotic protein, Bcl 2 and increased expression of the pro-apoptotic protein, Bax. This finding was confirmed by the downregulation of Bcl-2 gene and upregulation of the Bax gene in the treated hepG2 cells. Conclusion: Clausenidin extracted from Clausena excavata Burm.f. is an anti-hepG2 cell compound as shown by its ability to induce apoptosis through the mitochondrial pathway of apoptosis. Clausenidin can potentially be developed into an anticancer compound

Prevalence and Determinants of Endothelial Dysfunction among Adults Living with HIV in Northwest Nigeria

Background: Endothelial dysfunction constitutes an early pathophysiological event in atherogenesis and cardiovascular disease. This study aimed to assess the prevalence, determinants, and degree of endothelial dysfunction in antiretroviral therapy (ART)–treated people living with HIV (PLWH) in northwestern Nigeria using brachial flow-mediated dilatation (FMD). Methods: This was a comparative, cross-sectional study. A total of 200 ART-treated adults living with HIV with no evidence of kidney disease were compared with 200 HIV-negative participants attending a tertiary hospital in Kano, Nigeria, between September 2020 and May 2021. Endothelial function was evaluated by measuring FMD with a high-resolution vascular ultrasound transducer. FMD was calculated as the ratio of the brachial artery diameter after reactive hyperemia to baseline diameter and expressed as a percentage of change. Blood and urine samples were obtained from participants in both arms. Urine albumin-to-creatinine ratio (uACR) was calculated using the 2021 CKD-EPI estimated glomerular filtration rate (eGFR) creatinine-cystatin C equation without the race variable, and low-density lipoprotein (LDL) cholesterol was measured using enzymatic method. Results: The overall mean age (± standard deviation) of the study participants was 42 ± 11 years. Participants in the comparison arm were younger than PLWH (38 ± 11 versus 46 ± 10 years, respectively). The median (interquartile range) uACR was 41.6 (23.2–162.9) mg/g for the ART-treated PLWH versus 14.5 (7.4–27.0) mg/g for healthy controls. PLWH had a significantly lower mean percent FMD when compared to HIV-negative participants (9.8% ± 5.4 versus 12.1% ± 9.2, respectively). Reduced FMD was independently associated with HIV infection (β = –2.83%, 95% CI, –4.44% to –1.21%, p = 0.001), estimated glomerular filtration rate (β = –0.04%, 95% CI, –0.07% to –0.01%, p = 0.004) and LDL cholesterol (β = –1.12%, 95% CI, –2.13% to –0.11%, p = 0.029). Conclusion: HIV-positive status, lower estimated GFR, and higher LDL cholesterol levels were independently associated with endothelial dysfunction. Future prospective studies with larger cohorts of persons living with HIV (and age- and sex-matched HIV-negative controls) are needed to gain further insight into these important findings. In the interim, aggressive management of modifiable risk factors is warranted

Carbapenem resistance expressed by Gram-negative bacilli isolated from a cohort of Libyan patients

Background and objectives: Carbapenem-resistant Enterobacteriaceae (CRE) and other Gram-negative bacteria are among the most common pathogens responsible for both community and hospital acquired infection. The global spread of cephalosporinases in Enterobacteriaceae has led to the increased use of carbapenems resulting in the emergence and rapid spread of CRE. This has become an alarming public health concern, yet the condition in Libya remains unclear. The aim of this study was to obtain a better understanding of CRE strains prevalent in Libyan patients by investigating their phenotypic characteristics and antibiograms. Methods: Gram-negative bacterial species were collected from Misrata Central Hospital, Misrata Cancer Centre and Privet Pathology Laboratories. Clinical samples and swabs were obtained from hospitalised and non-hospitalised patients and from mechanical ventilation and suction machines. Patients who had received antibiotic therapy for at least three days prior to the study were excluded. The identification and characterization of the isolated species were achieved using the growth characteristics on MacConkey and blood agar, spot tests and API 20E or API 20NE biochemical testing systems. Screening for carbapenem resistance was performed using the disk diffusion method with carbapenem 10 μg and cephalosporin 30 μg disks and minimum inhibitory concentrations (MIC) determined using the Sensititre Gram-negative Xtra plate format (GNX2F). All strains demonstrating resistance or reduced susceptibility to one of the four carbapenems were subjected to carbapenememase activity detection using the RAPIDEC CARBA NP test, Modified Hodge test and carbapenem inactivation methods. Results: A total of one hundred and forty isolates representing fourteen bacterial species were isolated from 140 non-duplicated specimens. Clinical specimens included urine samples (96/140, 68.57%), sputum (15/140, 10.71%), surgical wound swabs (18/140, 12.85%), foot swabs from diabetes mellitus (DM) patients (6/140, 4.29%), ear swabs (3/140, 2.14%) and wound swabs (2/140, 1.43%). Thirty-four (24.29%) isolates demonstrated resistance to at least one of the four carbapenems with Klebsiella pneumoniae representing 73.53% (25 isolates) of all carbapenem resistant species, followed by 8.82% for Pseudomonas aeruginosa (3 isolates), 5.88% for both Proteus mirabilis (2 isolates) and Escherichia coli (2 isolates) and 2.94% for both Citrobacter koseri (1 isolate) and Rahnella aquatilis (1 isolate). The other isolates were either susceptible or cephalosporinase producers. Conclusion: This study has revealed the high rate of carbapenem resistance amongst Libyan patients and emphasizes the crucial need for accurate screening, identification and susceptibility testing to prevent further spread of nosocomial and community acquired resistance. This may be achieved through the establishment of antibiotic stewardship programmes along with firm infection control practices.National Research Foundation of South Africa; Libyan GovernmentWeb of Scienc