COMPARATIVE STUDY OF BS 8110 AND EUROCODE 2 IN STRUCTURAL DESIGN AND ANALYSIS

This work was undertaken to compare the use of BS 8110 and Eurocode 2 in the design of structures and focused on outlining the relative gains and/or shortcomings of Eurocode 2 and BS 8110 under certain criteria which are loading, analysis, ease of use and technological advancement. To accomplish this, the analysis and design of the main structural elements in reinforced concrete building was undertaken using the two codes. A modest medium rise building was loaded using the two code and analyzed. Analysis was done using CSI start tedds to obtain the shear force and bending moment envelopes. For the beam, it was found that Eurocode 2 gave higher internal supports moments. For the case of maximum span moments and shear force values, the Euroode 2 values lagged behind. Column load and moments values were generally lower for Euroode 2. In summary, the comparative benefits of using Euroode 2 are that it is logical and organized, less restrictive and more extensive than the BS 8110. The new Eurocodes are claimed to be the most technically advanced code in the world and therefore should be adopted by Nigerian engineers. http://dx.doi.org/10.4314/njt.v36i3.1

Relationship between sonographic umbilical cord size and gestational age among pregnant women in Enugu, Nigeria

Background: Common fetal parameters for gestational age (GA) estimation have pitfalls especially in advanced pregnancy and pregnancy complicated by fetal structural anomaly.Objective: To assess the relationship between umbilical cord size and gestational age of the fetus.Subjects and Methods: A sonographic cross sectional study involving 300 pregnant women with GA between 14 weeks to 40 weeks was done in Enugu, Nigeria. Gestational ages were first estimated by use of Naegele’s formula for GA estimation based on the date of onset of each subject’s last menstrual period. Fetal parameters such as biparietal diameter, femur length, head circumference and abdominal circumference were measured and also used to estimate GA. Umbilical cord diameters were measured and used to compute the umbilical cord cross-sectional area.Results: The mean umbilical cord diameter and cross-sectional area were 14.5mm + 7.2mm and 201.6mm + 139.5mm2 respectively. Umbilical cord growth rate of 1.0mm/week was noted between the 14th and 35th week of pregnancy. There were significant correlations (p < 0.001) between umbilical cord size and other fetal parameters for GA estimation.Conclusion: Umbilical cord size had strong linear relationship with common fetal GA estimation parameters and could be used to compliment these parameters for GA estimation.Key words: Sonography, umbilical cord size, gestational age, Nigeria

Seismo-Structural Interpretation and Petrophysical Evaluation of Ugwu-Field, Coastal Swamp Depositional Belt of the Niger Delta Basin

Structural interpretation of 3-D seismic data and well log have been applied to unravel hydrocarbon entrapment pattern and petrophysical parameters of X-field within the coastal swamp region of the Niger Delta.. Four reservoir intervals (A, B, C and D) delineated as (W-026, 032, 042 and 048) using gamma ray and resistivity log response. Structural interpretation for inline 5158 revealed four horizons (A, B, C and D) and eight (8) faults labelled (F1, F2, F12, F13, F21, F22, F23, and F24) were mapped. It was observed that the hanging wall block due to reverse drag or rollover anticline slided over fault F12 and created fault F2, thereby creating subsidence where sediments can be deposited. Therefore, faults F2 and F12 created rollover structures which cuts across the entire four reservoirs and invaluably responsible for trapping of hydrocarbon in the field. RMS map developed for horizons \u2018A\u2019 and \u2018B\u2019 revealed high amplitude anomalies, while variance attribute for both horizons showed relatively uniform lithology observed from east to west across the study area. While from north-east to south west, variance was observed to increase relatively which indicates different lithology. These trend exposes dipping of the channel fill at both flanks by creating extensive faulting. Results of petrophysical evaluation for reservoirs \u2018A\u2019 and \u2018B\u2019 across the four wells were analyzed. For reservoir \u2018A\u2019, porosity values of 32.8%, 24.8%, 25.9% and 27.1% were obtained for wells W-048, 042, 026 and 032 respectively with an average of 27.65%, while for reservoir \u2018B\u2019 porosity values of 26.83%, 26.93%, 25.59% and 27.99% for wells W-048, 042, 026 and 032 were obtained respectively with an average of 26.84%. This porosity values were rated very good to excellent for reservoir \u2018A\u2019 and very good for reservoir \u2018B\u2019, while Permeability values of the order (K > 1000mD) were obtained for both reservoirs across the four wells and is rated excellent. Hydrocarbon saturation (Shc) across the four wells averages at 68.57% for reservoir \u2018A\u2019 and 68.67% for reservoir \u2018B\u2019 which is high. Log motifs using gamma ray log for well-026 was integrated with seismic facies to infer on depositional environment of the reservoirs horizons showed a combination of serrated funnel/blocky shape log response and coarsening upward cycles. For reservoirs \u2018A\u2019, \u2018B\u2019 and \u2018C\u2019 the log shape pattern indicates deposition in a fluvial / tidal, channel environment while for reservoir \u2018D\u2019 the pattern indicates deposition in deltaic front environment. Isochore maps computed for horizons \u2018A\u2019 and \u2018B\u2019, shows that horizon \u2018A\u2019 is relatively thick and this pattern suggests increased tectonic activities during deposition of reservoir \u2018A\u2019 and is an indication that reservoir \u2018A\u2019 is a synrift deposit

Performance of oyster mushroom (Pleurotus ostreatus) in different local agricultural waste materials

The present study was conducted to evaluate different substrates for establishment of yield performance of oyster mushroom (Pleurotus ostreatus). The substrates were prepared from single or mixture of different agricultural waste materials supplemented with lime and water as additive to each substrate. A total of eight substrates labeled 1 to 8 were prepared. Substrate 4, which is a mixture of palm kernel cake and maize cob, had the highest mycelia growth rate (80%), sprouted 15 days after inoculation and yielded the highest total fresh weight for a period of 10 harvests (2957.5 g). Substrate 3, a mixture of palm kernel cake and sawdust, had 78% mycelia growth rate, sprouted 16 days after inoculation and yielded 2535.7 g fresh mushroom. Substrate 2 is a mixture of maize straw and sawdust and had 75% mycelia growth rate, sprouted 17 days after inoculation and a total of 2207.4 g fresh weight. The mushroom grown in substrates 4, 3 and 2 produced bigger and firmer fruiting bodies, which differed significantly (P < 0.05) from the other substrates. Substrates 1 and 5 which had 50% mycelia growth rate, sprouted 31 and 33 days after inoculation and 1408.8 and 1092.6 g, respectively, were recorded after a period of 10 harvests. Substrate 4, 3 or 2 is therefore recommended for cultivation of oyster mushroom.Keywords: Oyster mushroom (Pleurotus ostreatus), mycelial growth, palm kernel cake (PKC), substrate, maturit

Scale-up and large-scale production of Tetraselmis sp CTP4 (Chlorophyta) for CO2 mitigation: from an agar plate to 100-m(3) industrial photobioreactors

Industrial production of novel microalgal isolates is key to improving the current portfolio of available strains that are able to grow in large-scale production systems for different biotechnological applications, including carbon mitigation. In this context, Tetraselmis sp. CTP4 was successfully scaled up from an agar plate to 35-and 100-m(3) industrial scale tubular photobioreactors (PBR). Growth was performed semi-continuously for 60 days in the autumn-winter season (17th October -14th December). Optimisation of tubular PBR operations showed that improved productivities were obtained at a culture velocity of 0.65-1.35 m s(-1) and a pH set-point for CO2 injection of 8.0. Highest volumetric (0.08 +/- 0.01 g L-1 d(-1)) and areal (20.3 +/- 3.2 g m(-2) d(-1)) biomass productivities were attained in the 100-m(3) PBR compared to those of the 35-m(3) PBR (0.05 +/- 0.02 g L-1 d(-1) and 13.5 +/- 4.3 g m(-2) d(-1), respectively). Lipid contents were similar in both PBRs (9-10% of ash free dry weight). CO2 sequestration was followed in the 100-m(3) PBR, revealing a mean CO2 mitigation efficiency of 65% and a biomass to carbon ratio of 1.80. Tetraselmis sp. CTP4 is thus a robust candidate for industrial-scale production with promising biomass productivities and photosynthetic efficiencies up to 3.5% of total solar irradiance.Portuguese national budget; Foundation for Science and Technology (FCT) [CCMAR/Multi/04326/2013]; INTERREG V-A Espana-Portugal project [0055 ALGARED + 5 E]; COST Action - European Network for Bio-products [1408]; FCT [SFRH/BD/105541/2014]; Nord Universityinfo:eu-repo/semantics/publishedVersio

Algae as Protein Factories: Expression of a Human Antibody and the Respective Antigen in the Diatom Phaeodactylum tricornutum

Microalgae are thought to offer great potential as expression system for various industrial, therapeutic and diagnostic recombinant proteins as they combine high growth rates with all benefits of eukaryotic expression systems. Moreover, microalgae exhibit a phototrophic lifestyle like land plants, hence protein expression is fuelled by photosynthesis, which is CO2-neutral and involves only low production costs. So far, however, research on algal bioreactors for recombinant protein expression is very rare calling for further investigations in this highly promising field. In this study, we present data on the expression of a monoclonal human IgG antibody against the Hepatitis B surface protein and the respective antigen in the diatom Phaeodactylum tricornutum. Antibodies are fully-assembled and functional and accumulate to 8.7% of total soluble protein, which complies with 21 mg antibody per gram algal dry weight. The Hepatitis B surface protein is functional as well and is recognized by algae-produced and commercial antibodies

Micro-algae come of age as a platform for recombinant protein production

A complete set of genetic tools is still being developed for the micro-alga Chlamydomonas reinhardtii. Yet even with this incomplete set, this photosynthetic single-celled plant has demonstrated significant promise as a platform for recombinant protein expression. In recent years, techniques have been developed that allow for robust expression of genes from both the nuclear and plastid genome. With these advances, many research groups have examined the pliability of this and other micro-algae as biological machines capable of producing recombinant peptides and proteins. This review describes recent successes in recombinant protein production in Chlamydomonas, including production of complex mammalian therapeutic proteins and monoclonal antibodies at levels sufficient for production at economic parity with existing production platforms. These advances have also shed light on the details of algal protein production at the molecular level, and provide insight into the next steps for optimizing micro-algae as a useful platform for the production of therapeutic and industrially relevant recombinant proteins

Bioreactor for microalgal cultivation systems: strategy and development

Microalgae are important natural resources that can provide food, medicine, energy and various bioproducts for nutraceutical, cosmeceutical and aquaculture industries. Their production rates are superior compared to those of terrestrial crops. However, microalgae biomass production on a large scale is still a challenging problem in terms of economic and ecological viability. Microalgal cultivation system should be designed to maximize production with the least cost. Energy efficient approaches of using light, dynamic mixing to maximize use of carbon dioxide (CO2) and nutrients and selection of highly productive species are the main considerations in designing an efficient photobioreactor. In general, optimized culture conditions and biological responses are the two overarching attributes to be considered for photobioreactor design strategies. Thus, fundamental aspects of microalgae growth, such as availability of suitable light, CO2 and nutrients to each growing cell, suitable environmental parameters (including temperature and pH) and efficient removal of oxygen which otherwise would negatively impact the algal growth, should be integrated into the photobioreactor design and function. Innovations should be strategized to fully exploit the wastewaters, flue-gas, waves or solar energy to drive large outdoor microalgae cultivation systems. Cultured species should be carefully selected to match the most suitable growth parameters in different reactor systems. Factors that would decrease production such as photoinhibition, self-shading and phosphate flocculation should be nullified using appropriate technical approaches such as flashing light innovation, selective light spectrum, light-CO2 synergy and mixing dynamics. Use of predictive mathematical modelling and adoption of new technologies in novel photobioreactor design will not only increase the photosynthetic and growth rates but will also enhance the quality of microalgae composition. Optimizing the use of natural resources and industrial wastes that would otherwise harm the environment should be given emphasis in strategizing the photobioreactor mass production. To date, more research and innovation are needed since scalability and economics of microalgae cultivation using photobioreactors remain the challenges to be overcome for large-scale microalgae production