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Open Access
A proposed one-stop-shop approach for the delivery of integrated oral, mental, sexual and reproductive care to adolescents in Nigeria
(Pan African Medical Journal, 2020) Morenike Oluwatoyin Folayan; Nadia Adjoa Sam-Agudu; Abiola Adeniyi; Elizabeth Oziegbe; Nneka Maureen Chukwumah; Boladale Mapayi
The interconnectedness of oral, mental, sexual, and reproductive health (OMSRH) in adolescents prompts exploration of novel approaches to facilitate comprehensive access of this population to the relevant health services. This paper proposes an integrated one-stop-shop approach to increasing adolescents' access to OMSRH care by leveraging on dental clinics as a template for integration, using a non-stigmatized platform to deliver stigmatized healthcare. Novel healthcare delivery models are needed to enhance adolescents' access to the comprehensive prevention and treatment services that they critically need. Effective, integrated health care for this population is lacking, especially across various health areas. This is a proposal for leveraging dental clinics for integrated OMSRH care, using facility-based services, to adolescents. Emphasis will be placed on reducing stigma as a barrier to service accessibility, acceptability, equitability and appropriateness. Empirical studies will be required to test the feasibility, validity and effectiveness of this proposed model.
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Open Access
Influence of titanium solute additions on the microstructural and mechanical behaviours of Ni-B alloys
(Physics and Engineering physics,Obafemi Awolowo University, 2016) Zeblon, Ebimobowei Meshack
The study prepared seven ternary Ni-B-Ti alloys with varying compositions of titanium and one binary Ni-B alloy (control sample). It also determined the solidification path and phase formation of the alloys, their microstructures and their mechanical properties. This was with a view to determining the effect of varying amount of titanium on the microstructure and some mechanical properties of the Ni-B system. The components of the alloys were pure Ni, binary Ni-B containing 18.3wt%B and pure Ti.The components of each alloy were accurately weighed and then melted using an electric furnace. The samples were quenched in air after melting. Differential Thermal Analyzer (DTA) was used to study the solidification path and phase formation of the alloys. The heating and cooling rates ranged from 10-20oC/min. Scanning Electron Microscope (SEM) equipped with Energy Dispersive X-ray Analyzer (EDXA) and Optical Microscope (OM) were used to characterise the structures of the alloys. The sample for SEM and OM investigations were polished, then slightly etched with an etchant consisting of 5g FeCl3+10ml HCl dissolved in 50ml H2O.Instron machine was used to measure the compressive strength of the alloys while the hardness values of the alloys were measured with a micro-hardness tester on the Vickers and Rockwell-C scale. Microscopic and thermal investigations of the alloys revealed the presence of two major primary phases [Ni(α), τ] and other binary and ternary eutectic structures. Microsegregation was not observed in the quenched alloys due to their very high solidification rates. Upon subjection to slow cooling, the microstructures of the alloys becomes complex due to solid-state reactions and large undercoolings in the alloys. The addition of titanium to the Ni-B system led to a shift in microstructure of the alloys from the hypoeutectic to the hypereutectic region during slow cooling. Solid state (eutectoid) transformation of the τ phase was observed in alloys with low titanium contents. But such transformation was not observed for alloys with high titanium contents. The hardness values and Stiffness values of the Ni-B-Ti matrix increased with increase in titanium contents. The study concluded that Ni-B-Ti alloys which were suitable as coating materials to solve wear and abrasive problems in the engineering industries could also be applied to make the materials harder and stiffer.
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Open Access
Development of a Synchonous Data Transmission System.
(Obafemi Awolowo University, 1986) Agomo, Uchenna Udochukwu
The development of a 2 - channel synchronous data transmission system is presented. The system is capable of accepting at the input two separate analog voltage signals that have zeroto 1kHz frequency range and amplitude not greater than 2.5 volts. The two analog voltage signals are multiplexed at the input of the-system and converted to corresponding digital representations. These digital representations are then transmitted by means of digital gates from the transmitting section serially and with transmission clock frequency of 6.6 MHz, through cable wire to a remote receiving section, where the received digital representations are re-converted to analog voltage signals and demultiplexed to produce at the output, two separate analog voltage signals plus noise. The noise level does not exceed 5% of the signal level when filtered and leaves analog voltage signals with the same characteristics as those at the input of the system. The designed system is simple and can be used for laboratory demonstration on synchronous data transmission system. It may be useful as a communication medium for data exchange between two data processing terminals. The system may be used to transmit voltage signals from a central storage facility to a remote destination. In such circumstance the signals may be those derived from research results, medical findings and student/staff records. A computer base may then be set up and made accessible to users.
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Open Access
Allelopathic Effect of Aqueous extracts of Tithonia rotundifolia (P.M. Blake) and Murraya koenigii L. on the growth and biochemical constituents of Capsicum annuum L. and Corchorus olitorius L.
(Botany,Obafemi Awolowo University, 2012) Tijani, Musa Oyebamiji
The study was conducted to investigate the allelopathic effects of fresh shoot aqueous extracts of Murraya koenigii L. and Tithonia rotundifolia P.M. Blake on the growth and biochemical constituents of Capsicum annuum L. and Corchorus olitorius L. plants. Germination experiment was carried out by raising the seedlings of the two target crops in Petri-dishes lined with Whatman No 1 filter paper and moistened with 10 ml of different concentrations (50% and 100% representing half and full strength) of the aqueous extracts of M. koenigii and T. rotundifolia. For the growth parameters (shoot height, root length, number of leaves, leaf area, leaf area ratio ), yield parameters (fresh shoot and root weight, dry shoot and root weight) and quality parameters (chlorophyll, ascorbic acid and crude protein) analyses, potted plants were separated into the control and two other regimes namely: fresh shoot aqueous extract of T. rotundifolia (FSET) and fresh shoot aqueous extract of M. koenigii (FSEM). The pots were arranged in a completely randomized design. The control plants were supplied with 600 ml of tap water while the extract-treated plants were supplied with 600 ml of the appropriate aqueous extracts daily. Harvesting started at two weeks and continued thereafter on a weekly basis for six weeks. Chlorophyll accumulation, ascorbic acid, percentage nitrogen and crude protein content were determined using standard methods. The data were analyzed using Analysis of Variance (ANOVA) and Least Significance Difference (LSD p < 0.05). The extracts significantly inhibited the germination of the seeds and the plumule and radicle lengths of both target crops. This effect was extract concentration dependent (100% > 50% > Control). The applied extracts of M. koenigii plants significantly promoted virtually all the growth parameters such as shoot height, number of leaves, leaf area, leaf area ratio, fresh shoot weight, fresh root weight, dry shoot weight, dry root weight, chlorophyll a, chlorophyll b, total chlorophyll, ascorbic acid and protein accumulation of the two target crops. The aqueous extract of T. rotundifolia enhanced only the shoot height, leaf area, root fresh weight, chlorophyll a, chlorophyll b, total chlorophyll, ascorbic acid and protein accumulation in the shoot of C. annuum. The root length was however, significantly inhibited by both aqueous extracts. In the case of the potted plants, the effects of the extracts on the various parameters studied followed the order: FSEM > FSET > CONTROL and was target species dependent. The results presented in this work showed that FSEM had more pronounced stimulatory effects on the studied parameters than the FSET. It was evident that while the level of the allelochemicals in the extracts of the two donor plants was phytotoxic to and inhibited the germination and growth of the juvenile seedlings in the Petri-dishes, they, however, had a stimulatory effect on the growth of the matured potted plants as well as on the accumulation of the biochemical constituents studied.
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Open Access
Effect of Cassava Peel Ash on the geotechnical properties of some selected Lateritic Soil in Osun State.
(Obafemi Awolowo University, 2015) Mgboh, Chinedu Victor
This study is aimed at assessing the effect of Cassava Peels Ash (CPA) on the stabilization of lateritic soil with a view of improving its geotechnical properties. Lateritic soil samples were collected from three different locations namely, Ife-East, Ayedaade and Olorunda Local Government Areas in Osun state, Nigeria, and were termed sample A, B and C, respectively. Cassava Peels were procured from a local cassava processing factory at Oke-Baale, Osogbo, Osun State. The chemical composition of the soil samples and the CPA, and the geotechnical properties such as grain size, liquid limit (LL), plastic limit (PL), optimum moisture content (OMC), maximum dry density (MDD), California bearing ratio (CBR) and unconfined compressive strength (UCS)of the soil samples were determined in their natural states. The Cassava Peels (CP) were dried and calcined at 700oC for a period of 90 minutes in an electric furnace and the ash produced sieved through 425 µm sieve. The resulting CPA was added to the soil samples in incremental values of 2, 4, 6, and 8% by weight of the dry soil. Each soil sample was equally mixed with 4% lime by weight of the soil. The aforementioned geotechnical properties were determined for each Soil-CPA-Lime mixture. The data obtained from the tests were used to establish the optimum percentage of CPA. The results showed that the soil samples as well as CPA contain between 34 and 42% silicon dioxide. The soil samples are acidic with pH ranging from 4.2 to 5.8. Whereas the CPA is basic (pH = 11.4). On addition of CPA and lime, the LL of sample A increased from 39.0 to 41.2%, sample B decreased from 46.2 to 36.7% and sample C decreased from 35.8 to 33.4% at the ratios of 2, 2 and 4% CPA, respectively. The PI for soil sample A decreased from 3.6 to 1.7%, sample B decreased from 16.1 to 2.3% and sample C decreased from 12.4 to 2.6% at the ratios of 2, 2 and 4% CPA, respectively. The MDD generally increased for all the soil samples as % CPA increased. The MDD increased from 1558 to 2020 kg/m3, 1850 to 2080 kg/m3 and 1110 to 1940 kg/m3at the ratios of 8, 4 and 4 % for samples A, B and C, respectively. The CBR for samples A, B and C increased from 18.0 to 25.0%, 21.0 to 27.0% and 17.0 to 18.0%, at the ratios of 8, 8 and 4% CPA, respectively. The result of the UCS tests generally increased as the % CPA increased. The highest values obtained were 400, 285, 215 kN/m2at the ratios of 8, 8 and 4% CPA for samples A, B and C, respectively. The study revealed that a combination of CPA and lime has the potential of improving the geotechnical properties of lateritic soil but no optimum percentage of CPA could be established for the studied soil samples.