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

Assessment of sex differences in serum urea and creatinine levels following an acute spinal cord injury in albino rat models

Background: One of the most serious consequences of spinal cord injury (SCI) is progressive deterioration of renal function mostly as a result of urine stasis and ascending infection of the paralyzed bladder. Several studies have reported variable changes in serum urea and creatinine especially in people with chronic SCI. However, there is paucity of information on sex related differences in these parameters in response to SCI.Methods: A total of 24 adult albino rats weighing above 150g were divided equally into two groups, a control and experimental group (n = 12) each containing equal number of male and female rats. The experimental group animals were paralyzed by complete transection of spinal cord below T4 level after deep anesthesia with ketamine 75mg/kg. Blood samples were collected from both groups 5 days post SCI for analysis. Mean values of serum urea (mmol/L) and creatinine (μmol/L) for both groups were compared. P < 0.05 was considered as significant.Results: The results showed significantly higher levels (P < 0.05) of serum urea and creatinine in the male SCI models with mean values of 92.12 ± 0.98 and 2573 ± 70.97 respectively compared with their controls where the mean values for serum urea and creatinine were 6.31 ± 1.48 and 476. 95 ± 4.67 respectively. In the female SCI models, serum urea 13.11 ± 0.81 and creatinine 519.88 ± 31.13 were not significantly different from that of female controls with serum urea and creatinine levels of 11.71 ± 1.43 and 493.69 ± 17.10 respectively ( P > 0.05).Conclusion: Spinal cord injury caused a significant increase in serum Urea and Creatinine levels in the male models compared to the females. This indicated that males might have higher risk of renal dysfunction following SCI

Matrix-Norm Approach of Computing Levenberg-Marquardt Reg- ularization Parameter for Nonlinear Equations

In this paper, we present Levenberg-Marquardt method for solving nonlinear systems of  equations. Here, both the objective function and the symmetric Jacobian matrix are assumed to be Lipchitz continuous. The regularization parameter is derived using Matrix-Norm approach. Numerical performance on some benchmark problems that demonstrates the effectiveness and efficiency of our approach are reported and have shown that the proposed algorithm is very promising.Mathematics Subject Classification: 65H10, 65K05, 65F22, 65F35.keywords: Nonlinear system of equations. Levenberg-Marquardt method. Regularization. Matrix-norm. Global convergence

Over-diagnosis of malaria is not a lost cause.

BACKGROUND: Recent studies have highlighted the over-diagnosis of malaria in clinical settings in Africa. This study assessed the impact of a training programme implemented as part of an intervention trial on diagnostic behaviour of clinicians in a rural district hospital in a low-moderate malaria transmission setting. METHODS: From the beginning of 2005, a randomized controlled trial (RCT) of intermittent preventive treatment for malaria in infants (IPTi) has been conducted at the study hospital. As part of the RCT, the study team offered laboratory quality assurance, and supervision and training of paediatric ward staff using information on malaria epidemiology in the community. Data on clinical and blood slide confirmed cases of malaria from 2001 to 2005 were extracted from the hospital records. RESULTS: The proportion of blood slides positive for malaria parasites had decreased from 21% in 2001 to 7% in 2005 (p < .01). The proportion of outpatient and inpatient cases diagnosed as malaria ranged between 34% and 28% from 2001 to 2004 and this decreased substantially to 17% after the introduction of the package of training and support in 2005 (p < .01). There was no clear trend in the ratio of blood slide examined versus total diagnosis of malaria. CONCLUSION: It may be possible to change the diagnostic behaviour of clinicians by rigorous training using local malaria epidemiology data and supportive supervision

Molecular characterization of a cucumber mosaic cucumovirus isolated from lettuce in Egypt

AbstractCucumber mosaic cucumovirus (CMV) was isolated from lettuce plants (Lactuca sativa) showing virus like symptoms. Isolation was performed depending on specific polyclonal antibodies and Chenopodium quinoa as a local lesion host. Virus was purified from 200gm of virus-infected Nicotiana tabacum cv. White Burley leaves giving A260/280 ratio of 1.21 and a yield of 1.7mg. Purified virus preparation was used for rabbit immunization to produce specific polyclonal antibodies. IgGs were purified and evaluated by indirect enzyme linked immunosorbant assay (I-ELISA) to determine the dilution end point which found to be 1:512. Electron micrographs showed spherical virus particles of about 30nm in diameter. Virus coat protein (CP) molecular weight was determined using sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE), giving a single band of 25kDa within resolving gel. Immunocapture-reverse transcriptase-polymerase chain reaction (IC-RT-PCR) was used for the amplification of CMV coat protein gene (cp), the appearance of 657bp bands confirmed the expected size of such gene. Comparing virus cp gene sequence with the sequences of seven overseas isolates confirmed that the under study isolate was related to the CMV subgroup I

Impact of Urban Growth on Green Space in Maiduguri Metropolis, Borno State (1975 – 2015)

A green area in a city is an open space that is deliberately left untouched permanently. The trees, grasses and shrubs in a green area have special attributes associated with a planned city that nurture healthy living condition for the inhabitants of the city on a sustainable basis. The paper assessed the impact of urban growth on the green areas of Maiduguri city. Data was generated from the city plan and satellite images of 1975, 1986, 1999 and 2015 to determine the changing pattern of land use in the green areas. The study was conducted within an area of a 10 km radius that effectively housed the green areas of Maiduguri in 1975. The total area under study was 31,428 hectares comprising 3245 ha of green areas and 28,183 of other land use. In 1986 the green areas have reduced to 1889 hectares with a corresponding increase in other land use to 29,539 ha. The green area in 1999 has further reduced to 1114 ha with an increase of other land uses to 30,314 ha. The result indicated that the green area of 3,245 hectares in 1975 has virtually disappeared by 2015. At the same time, satellite images of the city suggest a progressive increase in other land uses (residential, institutional,commercial/industrial and transportation). The results indicated a tremendous decline in the green areas of the city. This can be attributed to a lack of adherence to planning rules and regulation and the growing need for housing and other infrastructural facilities in the city. The paper recommends the need for land-use land cover monitoring to restore the green areas in the city, pragmatic physical planning intervention by the government, an all-inclusive approach to green area management involving NGOs, individuals, traditional rulers and advocacy to regain the cities green areas among others. Keywords: Green Space, land use, Urban Growt

Strycnos spinosa decreases the blood glucose and lipid levels of diabetic albino rats

Diabetes mellitus has reached epidemic levels with an estimate of 451 million cases worldwide in 2017. Diabetes is a chronic disease that occurs when the pancreas does not produce enough insulin or when the body cannot effectively use the insulin. Strychnos spinosa has been used in folk medicine as a remedy for various diseases including diabetes but the exact mechanism of action is still unknown. The present study aimed to evaluate the hypoglycaemic and hypolipidemic effects of the methanolic extract of the Strychnos spinosa leaves on alloxan-induced diabetic albino rats. Diabetes mellitus was experimentally induced in rats by intraperitoneal injection of alloxan monohydrate at a dose of 150 mg/kg. The pure extract of S. spinosa leaf was given orally once daily for 2 weeks in three graded doses of 150, 300 and 500 mg/kg and glibenclamide was used to treat the positive control group. Following treatments, the glucose level and lipid profile assay were carried out using colorimetric methods. The extracts significantly reduced (p&lt;0.05) the fasting blood glucose, TAG and cholesterol levels of the diabetic and non-diabetic rats. Treatment with the extract also decreased mortalities of the diabetic rats. These findings provides evidence to the increased use of the plant in folk medicine

Ribosomal DNA variation in landraces of bambara groundnut

The ribosomal DNA (rDNA) is a basic component of all eukaryotic chromosomes which codes for rRNA. The rDNA is made of tandemly repeated units of 18S, 5.8S, 28S, ITS and IGS. The 18S, 5.8S and 28S are coding regions while the ITS and IGS are non coding. The rDNA evolves in a concerted manner such that rDNA units within an individual are almost completely identical making it a useful tool in taxonomic studies. The rDNA marker is used to discriminate between species in the same or different genus. Bambara groundnut is an under-utilized legume that is highly nutritious and adapted to low input farming systems. Despite its potential, Bambara groundnut is still cultivated in the form of landraces, and no true varieties have been developed. Precise estimate of genetic variation and genetic relationship is sine qua non for the development of improved cultivars. About 48 individual seeds (3 each) from seven landraces of Bambara groundnut, 9 wild/cultivated species of other legumes (cowpea, mungbean and groundnut) were used in this study. Analysis of the rDNA gene unit shows genetic variation in the species of the genus Vigna and Arachis. The UPGMA dendrogram constructed separates the plant species in this study into three (3) main clusters. The landraces of Bambara groundnut were placed in two different clusters indicating variation of rDNA gene units between the landraces. The analysis of rDNA gene in this study reveals the presence of genetic variation between the landraces of Bambara groundnut which could be used by scientists and breeders in the production of improved cultivars.Keywords: Ribosomal DNA, Bambara groundnut, ITS, IGS, DNA variationAfrican Journal of Biotechnology Vol. 12(35), pp. 5395-540

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