Rivers State University of Science and Technology

About: Rivers State University of Science and Technology is a education organization based out in Port Harcourt, Rivers, Nigeria. It is known for research contribution in the topics: Population & Threatened species. The organization has 1826 authors who have published 1833 publications receiving 15183 citations.

Design and Fabrication of a Modified Portable Biogas Digester for Renewable Cooking-Gas Production

Abstract: This research paper focuses on re-engineering design and fabrication of a modified potable biogas digester for the production of biogas as a renewable energy source for domestic use. Digesters used around the world are commonly big in size. There is need to modify and re-engineer an existing biogas digester to fit in to modern day design for better efficiency, portability and safety. Floating drum and Flexible balloon are digesters to be modified as a thin walled pressure vessel with radius-thickness ratio greater than 10. ASME codes and standards were used to carry out the sizing calculations, thickness and pressure calculations for the cylindrical pressure vessel shells and also calculations for the storage tank hemisphere shell. AISI 304 (Chromium-Nickel steel) is used for the vessel shell and the maximum allowable stress is 137 MPa. Weld efficiency (85%), corrosion allowance (0.02mm), of 24 (for digester), of 18 (for collector) and of 20 (storage tank). 17 kg of cow dung and 34 kg of water with temperature of 32 o C were the raw materials used for this research to produce a cumulative gas volume of 0.1243 m 3 for 30 days. Furthermore, a bike pump is modified and used to increase methane gas pressure from 4.903 kPa to 345 kPa to suit the modern day gas cookers design and storage tank. Unlike other biogas plant, an electronic smoke alarm detector (model: Ei100) is placed 300 mm below the digester top for effective fire protection. Series of tests were performed to ensure that the constructed prototype met the specifications/standards. Such test include, smoke detector test, pressure testing, gas leak test, and a unit test run also confirmed that the aim of research was achieved.

Effect of cassava based diet on some heamatological parameters in albino rats fed petroleum contaminated diet

Abstract: The study was carried out to ascertain the effect of a cassava based diet (gari) on crude oil heamato-toxicity in albino rats by feeding diet contaminated with various concentrations of crude oil mixed with 20% gari to determine the protective effect of gari. The haematological parameters haemoglobin (Hb), Packed cell volume (PCV) and white blood cell count (WBC)(Total and differential) were monitored in the animals. Gari feeding at 20% caused insignificant dose dependent decrease in Hb and PCV but significant dose dependent white blood cell count in gari fed albino rats compared with Petroleum fed albino rats (P<0.05). Dose dependent decrease in Hb, PCV and white blood cell count was also observed in petroleum fed rats compared with their controls (P<0.05). The study showed that ingestion of petroleum contaminated diet caused decreased haemoglobin (Hb), Packed cell volume (PCV) and white blood cell count, an indicator of possible blood damage but supplementation of the diet with 20% gari decreased the haemoglobin (Hb), Packed cell volume (PCV) and white blood cell count observed in petroleum fed albino rats. This study showed that feeding on gari diet did not reverse the damage caused by crude petroleum as evidenced by insignificant differences in Hb and PCV concentrations possibly as result of cyanide present in the gari. Industrial relevance Cassava is a staple food in human diets in over 80 countries (Gomez, et al 1988). Gari a starchy food prepared from cassava (Manihot utilisima) tubers is one of the most popular staple foods of the people of the rain forest belt of West Africa. Gari contains mainly starch-20% amylase and 70% amylopectin having lost the soluble carbohydrates. Crude petroleum is capable of eliciting haemolytic toxicity of the blood cells in conditions of long- exposure causing decrease haemoglobin, white cell count and PCV levels. The study was carried out to see the effect of gari, a staple food on haemolytic toxicity caused by crude petroleum. Keywords: Cassava; Gari; Petroleum; haemato-toxicity

Plasmid Profile and Antibiotic Resistance Pattern of Bacteria from Abattoirs in Port Harcourt City, Nigeria

Abstract: Several activities occur in abattoirs including receiving, slaughtering and sale of cattle for meat protein. In rearing of these animals, antibiotics and vaccines are incorporated as part of their meals as well as in the treatment of their infections. The regular use of antibiotics leading to the increased occurrence of antibiotic resistant organisms worldwide and also from abattoir samples, has prompted the determination of plasmid profile in these microorganisms as the plasmids act as a faster means of transmission of resistance genes. This study was thus aimed at determining the plasmid profile of multi-resistant microorganisms isolated from abattoirs. Several samples including swabs from the tables, cow blood, faecal matter and service water were collected from the Iwofe, Rumuodumaya and Trans-Amadi abattoirs located within Port Harcourt City. Antibiotics including Gentamicin (10 µg), Ofloxacin (5 µg), Augmentin (30 µg), Ceftazidime (30 µg), Cefuroxime (30 µg), Nitrofurantoin (300 µg), Cefixime (5 µg) and Ciprofloxacin (5 µg) were used to determine the sensitivity pattern of the isolated microorganims.The plasmid profile of the multiple antibiotic resistant microorganisms was determined using standard microbiological procedures. From the results, gram-positive isolates of the genera Bacillus and Staphylococcus exhibited 100% resistance to Cefuroxime, Ceftazidime and Augmentin while they exhibited 100% susceptibility to Ofloxacin. The gram negative isolates including those of the genus Escherichia, Pseudomonas and Proteus exhibited 100% resistance to Cefuroxime as well as 100% susceptibility to Ofloxacin. Strains of Escherichia coli, Bacillus amyloliquefaciens, Bacillus flexus and Klebsiella pneumoniae lacked plasmids while strains of Pseudomonas, Klebsiella, Escherichia, Staphylococcus aureus and Proteus mirabilis had at least one plasmid each. The absence of plasmids in some of these isolates, indicate that their resistance may be chromosome-mediated and not plasmid-mediated. The occurrence of plasmids in multi-resistant microorganisms, poses a serious public health threat as other susceptible organisms may become resistant to the regularly used antibiotics over time.

Distance-Generated Field Density Estimates for the Threatened Sahel Tortoise Centrochelys sulcata</i

Abstract: In this paper, the results of the first density investigations (via Distance methodology on line transect surveys) for the threatened African spurred tortoise Centrochelys sulcata from West African Sahel (Niger and Burkina Faso) are reported. Spurred tortoises were encountered in 51.8% of Burkina Faso transects ( n = 27) and in 60.7% of Niger transects. In several transects we found evidence of the tortoise presence, but without actually seeing any individual. Pooling all the transects from which tortoise density was calculated, the mean density of tortoises in Burkina Faso was 0.0021 ind./ha, and in Niger was 0.167 ind./ha. Nonetheless, there was a considerable variability in density estimates by transect in both countries, and especially in Tenere-Termit (Niger), the density of tortoises was very high (over 2 ind./ha). Tenere-Termit region in Niger may therefore represent a potentially crucial area for the conservation of this declining species.

From diurnal to nocturnal activity: a case study of night-light niche expansion in Agama agama lizards

Abstract: Most species of lizard are either diurnal or nocturnal, and it is extremely rare to find species that operate both diurnally and nocturnally, or that may shift from diurnality to partial nocturnali...