Effect of Temperature and Catalyst on Biofuel Yields from Pyrolysis of African Copaiba Balsam (Daniellia Oliveri) Sawdust

The effect of sodium carbonate (Na2CO3) on biofuel yields from pyrolysis of Daniellia oliveri sawdust in a fixed bed reactor has been studied. The sawdust was procured from the New Sawmill, along Ilorin-Ibadan expressway, Ogbomoso, South-Western Nigeria. The sample was sundried for three days to reduce its moisture content. Catalytic pyrolysis of the sawdust was performed with different weight percentages of catalyst (10, 20, 30 and 40 wt.%) in the feed. Noncatalytic pyrolysis was also performed for the same temperatures and biofuel yields from both sets of experiments were compared. Char yield increased with an increasing percentage of catalyst and were higher than those from non-catalytic pyrolysis in all but one case, the highest being 49.42% at 500 oC (biomass/catalyst ratio of 60/40) and the lowest, 15.41% at a non-catalytic temperature of 400 oC. Bio-oil yields at 400 and 600 oC followed the same trend up to biomass/catalyst ratio of 70/30 while the yields at 500 oC, though higher than those from noncatalytic experiments in most cases, did not significantly change with an increasing percentage of catalyst. The highest yield of bio-oil (37.64%) was obtained at 600 oC (biomass/catalyst ratio of 90/10) and the lowest (16.41%) at 400 oC (biomass/catalyst ratio of 80/20). Gas yields in most cases decreased with an increasing percentage of catalyst and were all lower than those from non-catalytic experiments, the highest yield (62.77%) obtained at a temperature of 400 oC (noncatalytic) and the lowest (19.73%) at 500 oC (biomass/catalyst ratio of 60/40)

Cacao Genetic Resources Conservation and Utilization for Sustainable Production in Nigeria

Theobroma cacao, the source of chocolate, is one of the most important tree-crop that serves the purpose of sustaining the economy of millions of households and the largest non-oil foreign exchange earnings in Nigeria. The management of cacao genetic resources as it affects sustainable production of cocoa in Nigeria is reviewed. These include details of the diversity present in the germplasm collections, their utilization in varietal development and current status of the field genebanks as revealed by DNA fingerprinting using single nucleotide polymorphisms (SNPs) markers. Factors contributing to continuing backlash in the annual outputs of cocoa in Nigeria are also highlighted. The prospects of advances in the science of cacao genomics for up-scaling production and its impacts on the improvement of the industry in the country are discussed

ESTIMATION OF ATTRIBUTABLE FRACTION FOR MALARIA IN PREGNANT WOMEN

 This study applied the estimation of logit model of fever risk as a disease function of parasite density, age and season to give a more precise estimate. The data used for this study was obtained from the University College Hospital (UCH). Asymptomatic carriage of malaria parasites occurs frequently in endemic areas and the detection of parasites in a blood film from a febrile individual which does not necessarily indicate clinical malaria. In areas of very high transmission such estimates of the attributable fraction may be imprecise because very few individual pregnant women are without parasites. Furthermore, non-malaria fevers appear to suppress low levels of parasitaemia resulting in biased estimates of attributable fraction. We therefore, propose a qualitative response regression model for obtaining precise estimates of the probabilities of pregnant women with different level of parasitaemia having fever due to malaria. Logistic regression methods which model fever risk as a continuous function of parasite density, age, and season to give a more precise estimates than simple analyses of parasite prevalence and overcome problems of bias caused by the effects of non-malaria fevers. The result indicate that age is not a predicting factor affecting the pregnant women living in endemic areas, and also season has a slight effect while the parasite level is a major factor

Molecular Characterization and Antimicrobial Susceptibility of Staphylococcus aureus Isolates from Clinical Infection and Asymptomatic Carriers in Southwest Nigeria

Few reports from Africa suggest that resistance pattern, virulence factors and genotypes differ between Staphylococcus aureus from nasal carriage and clinical infection.We therefore compared antimicrobial resistance, selected virulence factors and genotypes of S. aureus from nasal carriage and clinical infection in Southwest Nigeria. Non-duplicate S. aureus isolates were obtained from infection (n = 217) and asymptomatic carriers (n = 73) during a cross sectional study in Lagos and Ogun States, Nigeria from 2010–2011. Susceptibility testing was performed using Vitek automated systems. Selected virulence factors were detected by PCR. The population structure was assessed using spa typing. The spa clonal complexes (spa-CC) were deduced using the Based Upon Repeat Pattern algorithm (BURP). Resistance was higher for aminoglycosides in clinical isolates while resistances to quinolones and tetracycline were more prevalent in carrier isolates. The Panton-Valentine leukocidin (PVL) was more frequently detected in isolates from infection compared to carriage (80.2 vs 53.4%; p<0.001, chi2-test). Seven methicillin resistant S. aureus isolates were associated with spa types t002, t008, t064, t194, t8439, t8440 and t8441. The predominant spa types among the methicillin-susceptible S. aureus isolates were t084 (65.5%), t2304 (4.4%) and t8435 (4.1%). spa-CC 084 was predominant among isolates from infection (80.3%, n = 167) and was significantly associated with PVL (OR = 7.1, 95%CI: 3.9– 13.2, p<0.001, chi2- test). In conclusion, PVL positive isolates were more frequently detected among isolates from infection compared to carriage and are associated with spa-CC 084

Mutagenic Effects of Gamma Radiation on Eight Accessions of Cowpea (Vigna unguiculata

Abstract Mutagenesis is used for creating new genetic variability in cultivar improvement. Optimal mutagenic treatment is required for effective mutation induction in crop species. Therefore, radiosensitivity of cowpea accessions to gamma irradiation was investigated. Seeds of eight cowpea accessions were irradiated with 60 Co gamma radiation doses of 100, 200, 300, 400 and 500 Gy. The seeds were sown in pots to evaluate the treatment effects on seed germination (SG), seedling survival (SS) and growth habits of M1 generation. Data were analyzed using descriptive statistics. Low rates of SG (10% -45%) were recorded at higher doses (500 -400 Gy) in Ife Brown (IB) and its derivatives, whereas high SG rates (74% -94%) were observed in IT90K-284-2 across all treatments. Percentage SS was inversely related to gamma dosage. A wide range of LD50 for SG (329 -1054 Gy) and SS (149 -620 Gy) were observed across the cowpea accessions. Low LD50 scores for SG (329 -516 Gy) and SS (149 -357 Gy) were observed among cowpea with rough seed coat, whereas cowpea with smooth seed coat recorded higher LD50 for SG (521 and 1054 Gy) and SS (449 and 620 Gy). Seed germination LD50 and SS LD50 were highly correlated with mean coat thickness (0.899 and 0.937) than mean seed weight (0.621 and 0.678). Gamma irradiation of cowpea seed at low dosage (100 Gy) increased the vigor of M1 seedlings with respect to primary leaf area, terminal leaflet area, seedling height and plant height at six weeks. Doses of 200 Gy and above resulted in a progressive reduction in vigor of plant and seed setting of cowpea. Radio-sensitivity varied with cowpea genotype and was associated with seed testa texture, thickness and seed weight. Low gamma * Corresponding author. F. O. Olasupo et al. 340 irradiation treatment (100 Gy) may be used to enhance seedling vigor, vegetative growth and yield of cowpea at M1 generation

A Rationalist Critique of Sally Gadow’s Relational Nursing Ethics

The ethic of care proposed by Carol Gilligan in late twentieth century instantly elicited a wide range of adaptations and elaborations in numerous disciplines, under the banner of ‘relational ethics’. Sally Gadow’s ‘relational narrative’ is one of these adaptations. Like Gilligan, Gadow aims to dismantle ethical rationalism or universalism, wherein the foregoing mainstream nursing practice had purportedly focused on applying existing philosophical theories of ethics to all conceivable clinical situations. For Gadow, every moral engagement, such as that between a nursing professional and a patient, comes with inherent unique features that render impotent any attempt at universalisation. Each clinical encounter is rather defined by the ability of the professional to engage the client in an intimate, caring relationship that enables healing to take place. Against this backdrop, this paper argues that the theory of Relational Narrative, particularly as&nbsp; conceptualised and articulated by Sally Gadow, cannot be carried through without making some rationalist assumptions, because professionalism in nursing practice is by definition, a deeply embedded ingredient of rational reflection. Furthermore, nursing professionals can make progress or impact only by having recourse to the code of ethics; also, direct application of Gadow’s theory puts the nurse in a dilemma when it comes to dealing with patients suffering from chronic contagious diseases, such as the Ebola or the coronavirus disease (COVID-19). Finally, juxtaposing Gadow’s work with the ideas of the earlier scholars she criticises unsparingly, the paper found that traces of universalist, rationalist assumptions abound in her thought precisely because of the wealth of influence she has garnered from philosophers and psychologists; influences going as far back as Descartes and Kant, down to Rawls and Kohlberg. The data used for this study came from library and archival materials, as well as from internet resources. &nbsp

Studies on the Physicochemical and Physico-Mechanical Properties of Activated Palm Kernel Shell blended with Carbon Black filled NR Vulcanizates

Palm kernel shell was activated using chemical activation of H3PO4 and KOH. Various amounts of activated palm kernel shell (APKS) couple with carbon black (CB) and other conventional ingredients were used to produce natural rubber vulcanizates (NR vulcanizates). The NR vulcanizates were compounded on a two-row mill and tested for its physico-mechanical properties. The results for characterization of physicochemical properties carried out on APKS  were ash content (2.06%), moisture content (8.06%), %carbon (54.41%), particle size (4.00, 3.35, 2.00, 1.18mm), bulk density (0.62g/ml) and pH (5.3).The results show significant values for all, the moisture and ash content were within the recommended standard of ASTM (3-10max) and (< or =8) respectively. The filler loading concentrations CB/APKS were labeled as mixes 1 to 7. The composition of CB/APKS filler loading ratios were 30:0, 25:5, 20:10, 15:15, 10:20, 5:25, and 0:30 samples 1,2,3,4,5,6 and 7 respectively. Results obtained showed that CB/APKS filled vulcanizates exhibited improvement in the physico-mechanical properties investigated. The results obtained for CB/APKS across the samples filler loading shows that CB composition possess higher UTS, EB and rubber fatigue test while APKS filler loading composition exhibited higher hardness and young modulus. Abrasion resistance was excellent for both CB and APKS filler loading composition.Keywords: Activated Palm Kernel Shell, filler, carbon black, Chemical Activation, Natural Rubber