Towards ensuring scalability, interoperability and efficient access control in a multi-domain grid-based environment

The application of grid computing has been hampered by three basic challenges: scalability, interoperability and efficient access control which need to be optimized before a full-scale adoption of grid computing can take place. To address these challenges, a novel architectural model was designed for a multi-domain grid based environment (built on three domains). It was modelled using the dynamic role-based access control. The architecture’s framework assumes that each domain has an independent local security monitoring unit and a central security monitoring unit that monitors security for the entire grid. The architecture was evaluated using the Grid Security Services Simulator, a meta-query language and Java Runtime Environment 1.7.0.5 for implementing the workflows that define the model’s task. In terms of scalability, the results show that as the number of grid nodes increases, the average turnaround time reduces, and thereby increases the number of service requesters (grid users) on the grid. Grid middleware integration across various domains as well as the appropriate handling of authentication and authorisation through a local security monitoring unit and a central security monitoring unit proved that the architecture is interoperable. Finally, a case study scenario used for access control across the domains shows the efficiency of the role based access control approach used for achieving appropriate access to resources. Based on the results obtained, the proposed framework has proved to be interoperable, scalable and efficiently suitable for enforcing access control within the parameters evaluated.Department of HE and Training approved lis

Symptomatic, radiological profile of patients with endobronchial aspergilosis: a descriptive study

Background: Aspergillosis is a common presentation, involving respiratory system and is usually seen as a fungus ball that colonizes and grows into a pre-existing lung cavity, in the majority of cases secondary to pulmonary tuberculosis (PT). An endobronchial aspergilloma (EBA) is a rare disease, and another, but unusual, presentation of aspergillosis, characterized by the growth of Aspergillus species into the bronchial lumen. These two different presentations of aspergillosis can co-exist in the same patient. endobronchial aspergillosis, a variant of invasive aspergillus tracheobronchitis, a rare manifestation, where disease is limited to tracheobronchial tree without invasion of lung parenchyma and in many cases incidentally diagnosed, in a patient who had undergone a bronchoscopy to investigate haemoptysis, or for another reason.Methods: Patients who were attending respiratory OPD with symptoms of cough with expectoration with immune compromised status or previous history of tuberculosis with abnormal chest X-ray were subjected to chest CT scan, with abnormal endobronchial mass in CT scan were further investigated with fibreoptic bronchoscopy and histopathological examination.Results: 16 patients were diagnosed as endobronchial aspergilloma of which 11 patients were having past history of tuberculosis, 9 patients were having type 2 diabetes mellitus on treatment, 2 were having cardiac disease.Conclusions: IATB is a rare manifestation caused by Aspergillus species affecting people with immunocompromised status or previous respiratory pathology like tuberculosis leading to formation of mass like growth obstructing the airway lead to respiratory distress and it should be taken as differential diagnosis in patients with previous respiratory pathology presented with mass like growth in bronchi

Alkylating efficiency of sodium azide on pod yield, nut size and nutrition composition of Samnut 10 and Samnut 20 varieties of groundnut (Arachis hypogea L.)

Mutation has been utilised to improve growth and yield of many food crops, but only little effort has been made to ascertain the nutritional advantages in such improved crops. The present study evaluates the alkylating efficiency of sodium azide of different concentrations on pod yield, nut size and nutritional composition of two groundnut varieties. Dry seeds of groundnut (Arachis hypogea L.); Samnut 10 and Samnut 20 varieties obtained from the Ministry of Agriculture, Ilorin, Kwara State of Nigeria were treated with different sodium azide concentrations (10, 20, 30, 40 and 50mM) for 12 hours. Seeds soaked in distilled water for 12 hours were used as control for each variety. The treated seeds and control were sown in planting bags in randomized complete block design with three replicates. Alkylating effects of the treatments were studied on pod parameters and nut size while proximate analysis was carried out on the nuts to determine their nutritional composition. The results showed that sodium azide treatment of 50 mM produced significantly taller plants with more branches and leaves. Analysis of collected data revealed that sodium azide is effective in achieving significantly earlier- maturing plants with higher pod yield, bigger nut size and heavier nuts. All concentrations of Sodium azide applied induced significant higher crude protein and fat with respect to control in samnut 10 while 50 mM yielded highest protein and fat in samnut 20 variety. Generally, nutritional values of the studied groundnut were improved by sodium azide treatments with respect to protein and fat content which are the most important constituents in groundnut utilization as food or raw material for edible oil. The study concluded that the alkylating effect of sodium azide was effective on pod yield, nut size and other nut characteristics of groundnut and could be employed to improve protein, crude fat and other nutrition contents of the nuts for human and animal consumption as well as industrial applications.Key words: Alkylating effect, nutrition composition, sodium-azid

Neuroecotoxicology: effects of environmental heavy metal exposure on the brain of african giant rats

n/

MODIFICATION OF NIGERIAN BENTONITE FOR UTILIZATION IN OIL WELL DRILLING OPERATIONS

More than 80 bentonite clay deposit sites had been identified in Nigeria. Yet, almost all clay and additives used for drilling oil well are imported. The reason is partly that in their natural states, they do not swell while polymers in their raw forms remain unstable at high temperatures. This study aimed at evaluating the potentials of chemically modified Nigerian bentonite for application in the oil and gas industry. The Gombe bentonite from Gombe State was beneficiated using NAHCO3 and slurries were made by dispersion in distilled water. In the presence of other local additives, evaluation of the slurries was carried out on the basis of filtration loss and rheology at different temperatures (30, 60 and 85 oC) using a Central Composite Design (CCD). The clay sample was characterized for mineral and elemental compositions using X-ray diffractometer (XRD) and X-ray fractometer (XRF) while proximate analysis was carried out on the additives. At the optimum condition, the result shows a significant improvement in mud rheology and fluid loss at various temperatures which are in close agreement with the API recommended standard

Bacteriological pollution indicators in Ogun River flowing through Abeokuta Metropolis

Water resources are significant part of integrated community development policy and good health. Hence, the need to reduce the impact of natural and anthropogenic pollution causes so as to enhance water quality. The bacteriological quality of the Ogun River was investigated to determine the sanitary conditions of the water body between March and August, 2014. Total heterotrophic bacteria counts (THBC), total coliform counts (TCC) and total Escherichia coli counts (TEC) using standard plate count and Most Probable Number (MPN) techniques were determined. The isolates were identified using 16SrRNA gene. Total heterotrophic bacteria counts varied between 1.13 × 106 and 4.1 × 107 CFU/ml, TCC ranged between 2.5 × 105 and 2.33× 107 CFU/ml and TEC was between 5 × 104 and 1.3 × 106 CFU/ml. Most Probable Number of coliforms in all samples varied between 120 and 1600 MPN/100 ml. Isolated microorganisms include Escherichia coli strain SUS9EC, Escherichia coli O157:H7 strain SSI7, Escherichia coli strain BW25113, Escherichia coli strain C-X1B, and Klebsiella oxytoca strain KU-5. One-wayanalysis of variance showed significant difference within the samples at (P<0.05).The results revealed high bacteria counts which is higher than the recommended value of 1.2 × 102 for THBC, a zero E. coli count and not more than 10 coliforms per 100 ml by World Health Organization standards for drinking water.Keywords: Water, bacteria, Escherichia coli, pollutio

Structure of triosephosphate isomerase (TIM) from Methanocaldococcus jannaschii

The crystal structure of a recombinant triosephosphate isomerase (TIM) from the archaeabacterium Methanocaldococcus jannaschii has been determined at a resolution of 2.3 Å using X-ray diffraction data from a tetartohedrally twinned crystal. M. jannaschii TIM (MjTIM) is tetrameric, as suggested by solution studies and from the crystal structure, as is the case for two other structurally characterized archaeal TIMs. The archaeabacterial TIMs are shorter compared with the dimeric TIMs; the insertions in the dimeric TIMs occur in the vicinity of the tetramer interface, resulting in a hindrance to tetramerization in the dimeric TIMs. The charge distribution on the surface of the archaeal TIMs also facilitates tetramerization. Analysis of the barrel interactions in TIMs suggests that these interactions are unlikely to account for the thermal stability of the archaeal TIMs. A novelty of the unliganded structure of MjTIM is the complete absence of electron density for the loop 6 residues. The disorder of this loop could be ascribed to a missing salt bridge between residues at the N- and C-terminal ends of the loop in MjTIM

Threats to E-Government Implementation in the Civil Service: Nigeria as a Case Study

The rapid advancement in Information and Communication Technology (ICT) has undoubtedly influenced positive changes in carrying out administrative functions in government institutions. The ICT adoption rate in Africa is not impressive when compared to the more developed countries of the world. Nigeria, as a case study in this scenario, has also not implemented E-Government impressively, according to the required standards set up by the International Telecommunications Union (ITU). A comprehensive study conducted on the application and implementation of E-Government in Nigeria has provided some metrics that examine the stumbling blocks for realization of adequate and efficient E-Government implementation in the civil service. The research was carried out in the federal civil service in Nigeria in two phases namely, pre-IT implementation phase and post-IT implementation phase. Our findings reveal that ICT implementation will remain elusive in the civil service as long as the as threats explained below remain unaddressed. It has therefore been asserted that the need to overcome these threats is a precondition for realization of E-Government implementation in the federal civil servic

The cardio- and endothelial protective effects of ethyl methyl hydroxyl pyridine malate in modeling L-name induced nitric oxide deficiency

Currently, endothelial dysfunction is considered as a predictor of a number of pathologies, including arterial hypertension, ischemic heart disease, chronic heart failure, and is also a pathogenetic component of organ damage in diabetes, hypo estrogenic and other conditions. The purpose of the study is an experimental study of the cardio and vasoprotective effects of etoxidol under conditions of endothelial dysfunctio