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Geophysical and geotechnical methods remain one of the most effective approaches for the evaluation of subsoil properties prior to engineering construction. This is important in the delineation of soil sequence and estimation of soil parameters necessary for ensuring sufficient supports for structures. This study therefore presents the results of subsoil integrity and corrosivity probability evaluation using Vertical Electrical Sounding (VES) and Standard Penetration (SPT) in Ikate Area, Lagos, Nigeria. Data were acquired in eight (8) VES positions using Pasi terameter deploying the Schlumberger array system along four traverses while SPT-N values were obtained at every 1.5m within six (6) boreholes drilled to 30.0m depth in the study area. The combined results of VES and SPT delineate four to five geologic units corresponding to topsoil, different shades of clays, peat, sandy/clayey sand and sand. The low resistivity values of the clayey, peaty, and sandy layers especially along traverse four was used to rate them as highly or extremely susceptible to corrosion. The presence of highly compressible organic clay and peat in the second layer precludes the adoption of shallow foundation in the medium dense sandy layer that made up the topsoil (0.0 – 2.50m). Foundation analysis carried out with N-values shows that pile installed within the clayed sand/sand clay and sand layers encountered between 12.0 – 27.m with diameter range of 300 – 600mm could mobilize ultimate and allowable loads ranges of [702.9 – 5012.4KN] and [234.3 – 1670.8KN]. The correlations of resistivity with N-values returned high to weak positive linear relationships suggesting that resistivity values may not be effective in estimation of the strength and stiffness of subsoil. Conclusively, the study demonstrated the complimentary role of both VES and SPT as an effective geoengineering characterization tool.

The sedimentary facies exposed at Ogbunike Area belong to the Eocene Formation that made up the Anambra Basin. This research estimates the lithology, thickness, sedimentary succession, paleo-environment, reservoir quality and source area tectonics using geological mapping, petrography, grain size distribution and statistical analysis. Geological mapping shows that the section is approximately 27m thick and consists of sandstone, shale, siltstone and ironstone lithofacies. Granulometric analysis performed on selected samples shows that the sandstones are fine to medium grained (1.15 to 2.17 ϕ), moderately sorted (average 0.96 ϕ), fine skewed (average 0.16 ϕ) and leptokurtic (average 1.17 ϕ). Bivariate plot of skeweness against sorting and mean against sorting pinpoint a fluvial origin for the sandstones. The results from rose plot point to a bimodal-bipolar paleocurrent pattern while the bi-directional paleo-flow is in the northeastern-southwestern directions, which is an indication of tidal influence suggesting shore environment of deposition. Average permeability values derived from an empirical formula indicate good potential for reservoir rock. Deductions from field observations and petrographic analysis suggests that the sandstones are submature, with angular to sub-rounded quartz. The high percentage of goethite (average 30.4%) in the ferrugenized sandstones samples suggests an environment of low oxidation. Provenance and tectonic assessment reveal metamorphic source, humid climate, high relief, recycled orogeny, and derived primarily from Cameroon Basement Complex rocks.

Face recognition has found usage in many applications from the simplest systems to the more complex systems. The years of researches in this field has witness improvements in detection accuracy. However, few studies that incorporate face recognition for access control are suitable for restricted areas. This work aims at using face recognition for access control systems using Haar cascade feature descriptor and LBPH as classifier algorithm. The system was implemented on raspberry pi 3- model B board, which consists of a solenoid lock that is activated to grant access to the user when a matching face is detected by the classifier algorithm. In the event when there is no match between the detected face and the database facial images, a red light comes on and the doorbell rang. The accuracy, sensitivity, specificity, and precision of the LBPH algorithm are respectively 96%, 97.5%, 90.5%, and 97.5%. The delay in the processing of signals to activate the door lock and doorbell is not more than 4 seconds. Thus, the system is effective as a real-time access control mechanism. Keywords— Access control, Computer vision, Facial recognition, LBPH, OpenCV.

Users need more effective ways of organizing and searching for information. It has become increasingly difficult for users to findinformation on the World Wide Web that satisfies their individual needs since information resources on the World Wide Web continue to grow. The reason is that the World Wide Web provides a bunch of information that is generic in perspective. Although, the generic search engine makes attempts to streamline searching to search-key by traversing and combing the whole bunch of stored information. Under these circumstances, the system turns out to be inefficient and many times the results do not tally to what users desire. This paper presents a system to find interesting textual content among tons of documents taking the department of computer science of the University of Abuja, Nigeria as a case study. The paper proposed a vector space ranking algorithm which is a content-based ranking method that allows the user to utilize the full co-occurrence matrix of all words in the corpus to bring out relevant material using a simple and structured query interface. The index structures of the system have been specifically designed to support the ranking scheme. One important aspect of the system is its flexibility and robustness that makes it adaptable to any domain rather than being tailored to a particular one.

Building and construction industry in Nigeria has tremendously grown in the recent past owing to its contributions to national economy. Healthy and safety is an important aspect of the industry, yet, it remains unsatisfactory in terms of frequent occurrence of accidents and ill health on construction sites. Moreover, the occurrence of accidents on construction sites usually leads to site closure for investigation, loss of man/machine hours, loss of output, loss of corporate reputation, payment of burial expenses/compensation/insurance claims for the dead. These ugly incidents have necessitated the need for an effective health and safety management in the industry. This paper therefore analyzes the global situations of health and safety in the industry, examines the sources of accidents and ill health during construction and also investigates the health and safety management system and its challenges. The paper further analyzes the duties of parties involved in management of health and safety, communication of health and safety among the parties and assesses the strategies used in communication during design and construction stages.

Information Technology has grown rapidly leading to challenges with communicating information with nodes at remote locations. There are many communication media, and certain varieties of wired links such as coaxial cables, where multiple nodes can all be linked to hear each other's transmissions either properly, correctly or with some non-zero probability. Generally, there are two rudimentary ways of sharing such stations or media, which can be the time-sharing, and frequency sharing. This paper tackles the rudimentary question of how such one common communication channel also called a shared medium can be distributed among the distinct nodes with maximum productivity. It analyzes wireless sensor networks and its accompanying technologies sighting their pros and cons. Focusing on time-sharing, we examine methodically two prevalent approaches used in obtaining this which are either by time division (split) multiple access (TDMA) or contention protocols of which both approaches are widely being used in today’s systems. It also shows that with proper time of selecting the likelihood exigency of Tame Division Multiple Access’s (TDMAs), utilization tends to 1/e (37%) but also tends to increase collision. To adapt the transmitted message likelihood, a format for calculation was adopted. The idea was to seek to gather to the favorable point of value. Slotted Aloha has twice the utilization of Unslotted-Aloha when the numbers of accumulated nodes grow. The Study also shows that each node will stake transmission within sprinkling fixed number of slots and this is guaranteed when using a related distribution in a finite window, but this is not the case with geometric distribution.

In an emerging economy like Nigeria, internet-based businesses are growing at an exponential rate but this growth is highly threatened by many instances of fraud and e-systems’ compromise. While a lot of research work has been done on how to secure e-commerce transaction protocols, improve cryptographic schemes and amend the technical and business issues in e-commerce, the area of mitigating security challenges by incorporating security modules at design time has not been thoroughly explored. Hence, in this paper we present a framework for e-commerce security with a focus on four security design countermeasures models; Authentication, Authorization, enforcement of Access Control and Protection of Transaction privacy. The proposed framework which enhances National Institutes for Standards and Technology (NIST) security model, ensures that adequate security measures are incorporated in an e-commerce system at design time. The framework also ensures designing of secured e-commerce systems which are devoid of the expensive cost implication of system development life cycle incurred by security defects in the system testing phase which traces back to design shortfalls. For the purpose of this research work, we evaluate features called Malicious Attack Enablers (MAE) which aid malicious attack to thrive. The proposed framework will, therefore, aim at securing e-systems against these MAEs while satisfying legitimate user requirements. We assert the competence of our proposed framework by incorporating our security models into a SET enabled existing e-commerce system design, which will illustrate the effectiveness of our framework at the design phase as opposed to waiting till the testing phase. So we show that our new framework will unscramble the design of cost-effective e-commerce systems with curbed security vulnerabilities while contributing to the improvement of e-commerce security standards.&nbsp

Electronic Health Records (EHRs) are one of the exploding innovations in the twenty-first century. It serves as the backbone of medical operations in the developed countries. However, many developing countries including sub-Saharan Africa are yet to incorporate EHRs, despite the multiplicity of benefit it offers. This paper presents a design model that can be implemented in these economies. A work flow of operations in a typical hospital was defined and used in the design process. The patients’ data are captured through the front end application and these were stored on the database. A role based access level is assigned to caregiver through the incorporated fingerprint access control. All the caregivers’ workstations are connected to the EHRs via a configured server. The designed EHR system will enable optimization of clinical practices and management functions when deployed. The system is affordable to clinics and hospitals in the developing world. It can be adapted to meet the specific goals or requirements of an organization. Keywords: Health record, Healthcare, Hospital workflow, Electronic medical record

In this study, the concentrations of five selected heavy metals: Lead (Pb), Nickel (Ni), Mercury (Hg), Cadmium (Cd) and Selenium(Se) were determined in water and tissues of two fish species from Opa reservoir in Obafemi Awolowo University (OAU), Ile-Ife, Nigeria, with a view to assessing its pollution level. Water samples from the reservoir, and the liver, gills and fillet of six specimens of Tilapia zillii (Gervais, 1848) and six specimens of Momyrus rume (Curvier and Valenciennes, 1846) were analyzed using Flame Atomic Absorption Spectrophotometer (FAAS) for the selected metals. The mass order of the metals in the samples was:Pb>Ni>Se³Cd>Hg for water and Ni>Pb>Se>Cd3 Hg for the fillet of both T. zillii and M. rume fillet. Ni concentration ranges in T. zillii fillet and M. rume fillet were as follows 2.60-3.00 μg/g and 2.20-2.80 μg/g, with the mean concentrations of 2.77±0.151 μg/g and 2.57±0.23. Se ranged in T. zillii fillet between 0.80 and 1.20 μg/g with mean concentration of 0.97±0.061 μg/g and in M. rume fillet, it ranged between 0.60 and 0.80 μg/g with mean concentration of 0.73±0.103 μg/g respectively. The two metals (Ni and Se) were higher in T. zillii fillet at 95% confidence interval than M. rume. Nickel and Cadmium were significantly higher at 95% level in T. zillii gill than M.rume gill. Ni in T. zillii gill ranged from 2.28-3.20 μg/g with mean concentration of 3.20±0.360 μg/g while Cd ranged from 0.60-0.80 μg/g with mean concentration of 0.73±0.103 μg/g. The concentrations of Pb, Ni and Hg in Opa reservoir water were higher than the permissible levels for EPA, 2002; WHO, 1983; WPCL, 2004 and SON, 2007 while nickel was much higher in the fillet than the FAO, 1976 and FAO 1983 recommended limits of heavy metals in fish food. The study concluded that the Opa reservoir was heavy metal polluted.Keywords: Opa Reservoir, Heavy Metals, Mormyrus rume and Tilapia zillii

This study determined the concentrations of six heavy metals; cadmium (Cd), mercury (Hg), Chromium (Cr), Nickel (Ni), Arsenic (As) and lead (Pb) in the tissue (flesh and gills) of some frozen fishes sold in Ile-Ife main market using Flame Atomic Absorption Spectrometer. Open acid digestive method was used for sample dissolution. The results obtained showed that, metal concentrations in the muscles of different species were in the range of Ni 10.35-15.40μg/g; Cr, 0.29-0.38 μg/g; Pb, 0.42-0.49 μg/g; Hg, 0.34-0.47 μg/g; As, 0.06-0.07 μg/g; Cd, 0.04-0.07 μg/g with Ni > Pb > Hg> Cr> Cd > As, while in the gills values were: Ni, 9.93-12.67 μg/g; Cr, 0.21-0.33 μg/g; Pb, 0.21-0.43 μg/g;Hg,0.37-0.43 μg/g; As, 0.06-0.07 μg/g and Cd 0.03-0.06 μg/g with Ni > Hg> Pb > Cr > As > Cd. Concentrations of Pb and Ni were above the SON (2007) and WHO (2003) guidelines for fresh water and (EC, 2000) lead permissible value in fish muscles. They are therefore not ideal for consumption as other heavy metals present at varying concentration could bioaccumulate and biomagnify and may result into health related problems in consumer. This study recommends proper scrutiny of the seafood to safe guard the health of the people.Keywords: Heavy Metal, Market, Flame Atomic Absorption Spectrometer, Environment, Pollution, Anthropogenic Activity.

The objective of this work was to determine the metal content of plantain and banana peels ash derived alkali and the possibility of using it as alternate and cheap source of alkali in soap industry. This was done by ashing the peels and dissolving it in de-ionised water to achieve the corresponding hydroxides with pH above 12. The solution was then analyzed using Atomic Absorption Spectroscopy (AAS). The analytical measurements were carried out in triplicate and the multi elemental solution was used for calibration of equipment. The abundance of essential metals was in these orders in both the banana and plantain alkalis: K > Fe > Ca > Mg > Mn > Zn > Na and Fe > K > Ca > Mg > Zn > Mn > Na, respectively. The presence of other metals besides K and Na at higher concentrations limits the foamability of the soaps but could be adapted as thickeners and emulsifiers in greases. The concentrations of elements with health risk in the ash derived alkalis are within the allowable range of the Commission of European Communities (2008) limit.Key words: Banana, plantain, ash derived alkali, major elements, minor elements.

Patients with xanthinuria have biochemical abnormalities which include high concentrations of hypoxanthine and xanthine in plasma, higher concentration of xanthine than hypoxanthine and the low concentration of uric acid in plasma and urine1-3. However, it is unresolved why the concentration of xanthine is higher than that of hypoxanthine in plasma and urine. In the present study, using xanthine oxidase-deficient hepatoma-derived cell line HuH-7 cells, we tried to elucidate the mechanism that regulated oxypurines in patients with xanthinuria.

Xanthine oxidase was purified 1600-fold from human liver cytosol. The purified enzyme was shown as a single band of 300 kDa on polyacrylamide gel electrophoresis and 150 kDa on SDS-PAGE. Using this purified enzyme, polyclonal antibody against xanthine oxidase was raised in a rabbit. On Ouchterlony's double immunodiffusion method, the raised antibody and the human liver cytosol made a precipitation line stained by activity stain and protein stain, respectively. With the raised anti-xanthine oxidase sera, the immunohistochemical localization of xanthine oxidase in human tissues was examined. Immunostaining of frozen hepatic tissue section showed that the cytoplasm of hepatocytes and endothelial lining cells were stained. In a number of other tissues, the xanthine oxidase antigen was detected only in the endothelial lining cells from heart, kidney, brain, aorta, lung and mesentery, except for the duodenal mucosa cells. A possible role for xanthine oxidase in the endothelial cells from various human tissues in the pathogenesis of reperfusion injury was suggested.

The antibody was raised against purified human liver xanthine oxidase in a rabbit. In a xanthinuric patient, the double immuno-diffusion method demonstrated the existence of an immunologically reactive duodenal mucosa xanthine oxidase which did not possess xanthine oxidase activity. These results indicated that xanthine oxidase protein is abnormal in structure and/or amino acid sequence.

Four components are said to be involved in the uric acid transport system of the human kidney, but the definite mechanism of uric acid transport has not yet been clarified. We conducted both the benzbromarone (BZB) loading test and the combined pyrazinamide (PZA) and BZB test 1) to quantify the contribution of the four components involved in the renal handling of uric acid, 2) to determine whether BZB selectively inhibits postsecretory reabsorption of uric acid.

It has been reported that a raised serum uric acid is related to the development of atherosclerosis, but the direct association between hyperuricemia and atherosclerosis remains uncertain1). Therefore, in gout it seems important to investigate serum lipids which are among the known risk factors for atherosclerosis. In previous studies, some investigators suggested that hyperlipidemia in primary gout was secondary to excessive alcohol intake2) and/or obesity3), while others suggested that hyperlipidemia was a consequence of essential factors in primary gout4).