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Item BIOSYSTEMATIC STUDIES IN SOME NIGERIAN SPECIES OF ANTHERICUM LIN. AND CHLOROPHYTUM KER-GAWL. (LILIACEAE)(1981-03) ADEYEMI, F. A.Field surveys and investigations of representatives of Anthericum L. and Chiprophytum Ker-Gawl. complex in Nigeria were carried out in their natural habitats in at least sixteen States of the Nigerian Federation. All herbarium specimens in the Forestry Research Institute, Ibadan and in nine Nigerian Univetfsities visited were examined (if any). So far, ten species of Anthericum and fifteen species of Chlorophytum have been reported and collected in Nigeria. They were all studied morphologically. Detailed ecological analyses including the Chemical composition of their soils were carried out on three taxa of Anthericum and ten taxa of Chrolophytum. Many living populations were sampled from their different natural habitats in Nigeria, Their representatives were cultivated in three locations for experimental studies. Data were collected on the morphology by conventional methods and analysed. Anatomical data were amassed from the leaf surface patterns and the roots. Types of leaf margin anatomy were noted. Cytological studies were carried out in five taxa of Anthericum and eleven taxa of Chlorophytum. There were inter-generic hybridization tests. The use of lea f vein spacing interval and anther: filament ratio as taxonomic criteria have been suggested and their usefulness in the monocotyledon taxonomy, especially in Liliaceae, needed to be further explored. The importance of leaf margin anatomy as a taxonomic criterion above species level was highlighted. Chromosome counts for seven taxa were confirmed, viz; C. macrophvllum (A. Rieh.) Aschers 2n = 28. C. blepharophvllum gchwinf. ex Bak. 2n = 28. C. atenopetalum I Bak. 2n = 14. C. atenopetalum II (sp. nov.) 2n = 14. C. laxum R. Br. 2n = 14. C. inomatum Ker-Gawl. 2n = 14. C. togoense Engl. 2n = 14. New chromosome counts were recorded in :- C. geophilum Peter ex. v. Poelln. 2n = 28. C. alisaifolium Bak. 2n = 16. Chiprophytum X ( related to C. elatum ) 2n = 16. C . caulescens (Bak.) Marais & Reilly ( formerly A. caulescens Bak.) 2n = 16. A. Limosum Bak. 2n = 16. A. pterooaulon I Welw. ex Bak 2n = 24. A. Pterocaulon II 2n = 16. A. nubicum Bak. 2n = 16. A. pubirhachis Bak. 2n = 16. A. uvuiense 2n = 16. The possible evolution o f chromosome numbers in the complex has been postulated. The possible chromosome evolution o f the complex based on the available data from this work and existing literature has been proposed. Evidence was adduced to Support the Suggestion that the possible basic Chromosome number in the complex was x = 4, and that n = 8 Was a secondary basic number. It has also been contended that n =7 and n= 6 evolved from a more primitive n = 8. Supplementary evidence in Support of Marais and Reilly’ s (1978) transfer of A. caulescens from Anthericum into Chloronhytum as C. caulescens was adduced. A form of C.stenopetalum has been elevated to species level on account of its morphological, cytological and genetic differences. A new taxonomic key has been proposed for the Separation of Anthericum and Chiprophytum. The possible mode of evolution of some Nigerian species of Anthericum and Chlorophytum. based mainly on their leaf surface patterns, has been proposed.Item SPIN COMPLEXES IN FERROMAGNETISM(1988-11) AGBOOLA, A. I.The spin-wave theory in Heisenberg model of ferromagnetism is investigated with the Holstein - Primakoff transformation and with emphasis on the spin wave interactions. The temperature Tₒ below which the concept of magnons is valid is determined. By a special expansion formalism of operator (l-a+a/2S)1/2 which yields 1+(1-(1-1/2S)1/2 )a+a it is shown that quantized spin waves which behave like spin 1 quasiparticles (with dispersion relation ω~ k2 ) called magnons at temperatures T < Tₒ, are Bosons with an effective (negative) electrochemical potential µ that varies as T in the wave-wave interaction approximation. The various coefficients of Tv in the expression of the spontaneous magnetization M(T)/M(o) = l-(C1T3/2+C2T5/2+C3T7/2+C4T4) as well as the specific heat for some ferromagnets are calculated. The results are remarkably close to the experimental values obtained by other investigators. The method used enables one to deal especially with regimes of small spin values S for which µ differs substantially from zero. The influence of the chemical potential on some thermodynamic quantities are found for ferromagnets with Hexagonal-close-packed structures, as well as for cubic crystals, The existence of the spin wave interactions and hence of non-zero effective chemical potential is shown to give rise to a lowering of the thermodynamic internal energy with the implication that spin waves, on the average, form bound states called spin complexes. The kinematical as well as the dynamical interactions on the thermodynamic quantities are also found for some ferromagnets, by subjecting the magnons to intermediate statistics. The influence of the spin-wave-spin-wave-spin-wave interactions on the coefficients of Tv in the expression of the spontaneous magnetization of some ferromagnets are found to be negligible in comparison with wave-wave interactions. An attempt is made to extend the above calculations to spin complexes in antiferromagnetism, a phenomenon which seems to be relevant to high temperature superconductivity.Item MICROBIOLOGICAL STUDIES OF GUINEA CORN FERMENTATION FOR OGI-BABA PRODUCTION(1986-01) ADEYELE, S.Item An evaluation of the prevalence and intensity of liver fluke infection in cattle slaughtered in Jos abattoir with comments on the incidence of amphistome infection(1986) Okwuosu, V. N.; Ariyo, S. A.An evaluation of the prevalence of liver fluke disease of cattle revealed an upward trend for an urban abattoir. A total of 3072 animal gall bladders were assayed between December 1980 and January 1982 and 74.06 + 6.46% were positive, the major fluke species were Fasciola gigantic and diocrocoellum hospes with a few case of schistosoma bovis. The max/min. monthly prevalence rates were 85.42% and 60.00% respectively. The mean rates for D. hospes and F. gigantic were 57.95 + 6.58% nd 48.71 + 11.66% respectively. T-test assessments showed these mean to be significantly different. The study further showed that for natural infections of cattle mixed infections were more frequent than singe infections. The mean value were 32.13% as against X single infection rates of 25.5% and 16.45% for D. hospes and F. gigantic. Chi-square analysis confirmed that mixed infection rates were significantly higher than single infections for both species. The flike species were highly prolific, producing mac egg count of 50 x 103 and 60 x 103 c.p.ml for F. gigantic and D. hospes respectively. There was variation in egg count due to seasons with significantly more eggs produced in the dry than in the wet season, for freely infected animals, there wa suppression of egg production in mixed infections which though affecting the species, had more effect on F gigantic, this resulted in significantly more eggs being produces by either species in single than in mixed infectionsItem PHYSIOLOGICAL STUDIES ON BACILLUS SPECIES ISOLATED EROM FERMENTED AFRICAN LOCUST BEAN [PARKIA BIGLOBOSA (JACQ.) BENTH-](1988-09) ADERIBIGBE, E. Y.The physiological activities of Bacillus species that ferment African locust bean (Parkia biqlobosa (Jacq.) Benth] to produce ‘iru’ were investigated. The strains studied belong to the B. subtillis group and were designated BS1, BS2, BS3, BLl, BL2, BL4 and BP2. These seven strains showed significant differences (at α= 0.05) in growth and extracellular proteinases production. The following (descending) order was obtained for the growth of the organisms in liquid medium: BS3 > BS1 > BL4 > BL2 > BS2 > BL1 > BP2 The order of proteolytic activity (in descending Order) of the strains in nutrient broth medium containing African locust beans was: BL2 > BP2 > BS2 > BL4 > BS3 > BL1 > BS1 The best three strains (oh the basis of proteinase production) BL2, BP2 and BS2 showed further Variation in the production of other extracellular enzymes. The three strains produced amylase and polygalacturonase constitutively and varied amounts of sucrase and galactanase. Phytase activity was not detected in culture broth of strain BS2. None of the strains BS2, BL2 and BP2 produced pectinmethylesterase in nutrient broth medium with or without African locust bean. The three strains were lipolytic on tributyrate agar plates and produced trace amounts of lipase in broth medium containing African locust bean. In most cases, presence of African locust bean in culture medium enhanced production of extracellular enzymes significantly in the three strains. Agitation was found to be necessary for optimal production of extracellular proteinases by the strains BS2 and BL2. Among the carbon sources used, fructose and glucose repressed proteinase production significantly (at α = 0.05) in strain BS2 while raffinose and starch favoured proteinase production. Among the carbohydrates which favoured the production of proteinases are, inorder raffinose > starch > arabinose > galactose > sucrose. The effects of different nitrogen sources on proteinase production by strain BS2 were also investigated. Casein enchanced preduction but the effect was not significant (at α = 0.05) while other nitrogen sources repressed proteinase production significantly. The nitrogen sources repressed proteinase production in the Order: Leucine > Urea > KNO3 > NH4NO3 > Aspartic acid > Glutamic acid > Alanine. The presence of African locust bean in culture medium enhanced proteinase production in the three strains, but the effect was not significant (at α = 0.05). The crude proteinases of sttain BS2 had Optimum activity at pH 7.5. Optimum temperature for activity of the proteinases was 35°C, and the proteinases were relatively stable at 60°C, but were quickly denatured at temperatures > 70 C. The apparent Km of the crude proteinases of the strains BS2, BL2 and BP2 were approximately 39.14mg/ml, 33.29mg/ml and 44.1mg/ml respectively. Multiple proteinase bands were obtained after electrophoretic Separation of the crude enzymes in all strains. During purification, the proteinases were precipitated out between 55 - 70% of ammonium sulphate Saturation levels. There was a substantial loss in proteolytic activity during the salting out process. Three proteolytic activity peaks were obtained during ion-exchange chromatography of crude enzymes of strains BS2 and BL2. The peaks I, II and III were identified to be serine proteinase, neutral proteinase and an esterase (with low proteolytic activity) respectively. The serine proteinases of the two strains BS2 and BL2 showed hydrophobic properties. The molecular weights of the serine, neutral and esterase proteinases for strain BS2 were 29800, 24000 - 27400 and 33900 - 38400 respectively while those of strain BL2 were 18200 - 19700, 22600 and 33500 respectively. The purified neutral proteinase had higher specific activity than the serine proteinase while the esterase was characterized by low specific activity. The esterase was responsible for the multiple proteinase bands pattern observed in the electrophoresed crude enzymes. The possibility of selecting strains capable of producing wider variety and higher yields of extracellular enzymes to bring about more digestible fermented product is discussed.Item DESULPHURIZATION OF NIGERIAN LAFIA COAL FOR METALLURGICAL COKE PREPARATION(1988-01) ADERONPE, W. I. A.The Government-owned integrated iron and steel plant under construction in Ajaokuta has been designed to operate through the blast-furnace process. The blast-furnace requires metallurgical coal. It therefore became necessary and relevant to the national economy to scientifically work on Nigerian coals with a view to using same as metallurgical coal. Lafia coal is the only Nigerian coal that produces coke lump after dry distillation (carbonization). The property of coke- ability therefore attracted attention towards Lafia coal. The main interest was to so prepare the coal that as much as possible of it will be usable for metallurgical coke preparation for use in Ajaokuta blast-furnace. Lafia coal was subjected to chemical characterization and petrological studies. It became clear that it was high in ash and sulphur. Silicates, pyrites and carbonates of various elements constituted the inorganic mineral inclusions. Analytical data gave the sulphur varieties in Lafia coal to be organic (0.1 - 0.7%), pyritic (1.4 - 4.4%) and sulphate (0.01 - 0.07%). Pyritic sulphur which predominates in Lafia coal can be removed by physical means. Chemical desulphurization which is reducto-oxidative type of chemical reaction impares coal cokeability. A plunge was thus made for physical desulphurization techniques to bring down the total sulphur in Lafia coal to the level that will make it acceptable as a metallurgical coal with regards to its sulphur content. Trace elements in Nigerian coal ash determined using the Atomic Absorption Spectrophotometer (AAS) and confirmed with the Inductively Coupled Plasma Emission Spectrophotometer (ICPES) showed that the relative abundance of the elements in the coals depended on the biogeo-chemistry of the area of the deposit as follows: Lafia coal; F>Zn>Mn»V Cr>Ni>Cu>B>Pb>Ca>Be>Mo>Cd>Hg Enugu coal; B>Mn>V F>Cr>Zn>Cu>Pb Ni>Co>Be>Mo>Hg Okaba coal; Mn»B»V>Cr>Cu>Pb>F=Ni>Zn Co>Be>Mo>Hg Trace element content of coal was considered in connection with the impact of coal utilization on the environment. From the study it was concluded that either the wet concentrating table or the froth flotation method could be used to substantially desulphurize Lafia coal to meet the requirement of metallurgical coal.Item SOME ASPECTS OF THE ATMOSPHERIC ELECTRIC CLIMATE AT IBADAN(1980-07) ADEWOLU, D. O.The diurnal variations of the atmospheric electric Parameters and meteorological Parameters for the harmattan season of November 1978 to March 1979 are presented. The percentage variations of temperature are mirror images of those of vapour pressure which show pronounced depressions around noon when the little available moisture in the air near the ground is distributed over greater and greater heights by convection. The diurnal patterns of dust concentration, measured for the first time in this locality, is single periodic with minimum between 0400 hrs and 0800 hrs L.T. and maximum around 20 hrs L.T. This pattern is closely related to that of windspeed, and is explained in terms of the copious amount of dust transported southwards from the Sahara desert. The diurnal curves of the electric elements. I, H and p show pronounced “austausch” depressions around noon and marked peaks at 08.00 hrs which are attributable to the sunrise effect. An average value of the total nuclei concentration during the Harmattan months is computed to be about 2.8x10(10) particles per m(3) for this Station. This value is based on the measurements of the polar conductivities made for the first time in Ibadan.Item PETROLEUM HYDROCARBONS POLLUTION OF NIGERIAN WATERS AND SEDIMENTS AROUND LAGOS AND NIGER DELTA AREA OF NIGERIA(1989-03) ADEKANMBI, O. E.There is a paucity of scientific data on the levels and pattern of distribution of petroleum hydrocarbons in the Nigerian aquatic environment. The levels of total hydrocarbons in 241 water and 222 sediment samples in’ the major river systems draining into Nigerian coastal environment around Lagos and the Niger Delta area have been used to monitor the pattern of distribution of hydrocarbons within these areas over different weather regimes during 1984-85. The Utorogu pipeline oil spillage incident in Bendel State of Nigeria in 1984 was used as a case study for assessment of environmental impact of oil spillage in aquatic ecosystem in Nigeria. Samples were also collected and analyzed for total hydrocarbons from Kaduna (Northern Nigeria) and Ibadan (Western Nigeria) for comparative information and controls respectively. Water samples were analyzed for petroleum hydrocarbon by infrared (IR) and gas chromatographic (GC) techniques whereas sediment samples were analyzed by gravimetry and gas chromatography (GC). The infrared (IR) results for 1984 (wet season) showed that Lagos and Lekki lagoons had hydrocarbon level (presented as range followed by mean value in bracket), 1.64-11.40 (5.60) mg/1; Niger Delta, ND (net detectable)-70.70 (6.18)mg/1; Utorogu 0.17-10.50 (2.22)mg/1; Kaduna 4.30-9.90 (6.98)mg/1, while Ibadan water samples (serving as control area) showed no detectable levels of hydrocarbon. In 1985 (dry season) there was a decrease in the hydrocarbon levels found in the water samples. Lagos and Lekki lagoons recorded 0.10-0.41 (0.25)mg/1; Niger Delta 0.10-1.80(0.52)mg/1 and Utorogu 0.17-4.67 (2.14)mg/1. The gas chromatographic values for hydrocarbon concentration in water were much lower than the infrared values. All the samples except Upomani discharge point (3.36 mg/1) had values below 1 mg/1 by GC. Nonetheless, the IR values correlated well with the GC values. The corresponding hydrocarbon levels (on dry weight basis) in sediment samples in 1984 were: Lagos and Lekki lagoons ND-95.54 (30.33) µg/g; Niger Delta ND-74.05 (9.09) µg/g; Utorogu 14.04- 267.48 (98.88) µg/g and Kaduna 0.62-21.52 (12.36) µg/g. In 1985 the values of hydrocarbon levels recorded in the sediment samples were as follows: Lagos and Lekki lagoons 0.20-10.30 (4.20) µg/g; Niger Delta 0.05-44.06 (6.64) µg/g; Utorogu (Jan-Feb.) ND-9.41 (2.98) µg/g; Utorogu (June-July) 0.03- 68.06 (21.66) µg/g; Kaduna 2.91-5.00 (3.96) µg/g and Ibadan 8.09-27.79 (17.94) µg/g. The Lagos lagoon sediment samples monitored from January to December 1985 gave ND-2766.27 (11.13) µg/g. The results of this work showed that Lagos lagoon was more polluted than the Niger Delta in terms of petroleum hydrocarbons. Highest values of petroleum hydrocarbons were recorded close to oil activity points such as Ogharife field effluent canal, Chanomi creek at Egwa field, Orughene creek, in the Niger Delta area; or near human settlements such as Obotebe and Bakana or in an industrial area like Lever Brother's discharge point and Berger/National Oil/Ijora in Lagos. The results of Utorogu oil spillage gave a picture of the impact of oil in the aquatic environment. During the first sampling trip which took place within four months after the oil incident, aquatic lives (plants and animals) were seriously affected in the Utorogu swamp, but before the end of the study period (June 1985) the swamp had recovered and was bubbling with life again. Oil pollution indicator parameters such as the Carbon Preference Index (CPI), Pristane: Phytane ratio (Pr/Ph); Presence of Phytane, and Unresolved Complex Mixture (UCM) and the Marine Oil Pollution Index (MOPI) indicated that some of the stations were polluted by oil while most of the points studied in both Lagos and the Niger Delta were contaminated with petroleum hydrocarbons which may be from crude oil, refined oil or both. Moreover, all the contaminated and polluted samples showed petroleum hydrocarbon at different stages of weathering as reflected in their carbon range, the Pristane: n-C(17); Phytane:n-C(18) and UCM: n-alkane ratios.Item NEW CHROMONE ALKALOIDS FROM THE ROOT -BARK OF SCHUMANNIOPHYTON MAGNIFICUM (HARMS)(1981-09) ADEBOYE, J. O.The chemical investigations of some representative alkaloids of Rubiaceae are reviewed. The total syntheses of emetine and quinine are also reviewed while the biogenesis of anthraquinones and biosyntheses of chromones, nicotinic acid 'and nicotine are outlined. The bronchiodilator activities of Khellin and some chromone derivatives are compared and a brief review of the pharmacological activities of a few of the Rubiaceous alkaloids is given. From the methanol extract of the root-bark of Schumanniophyton magnificum, a well known chromone, 5, 7-dihydroxy-2-methylchromone (noreugenin) 97 was isolated in addition to five alkaloids designated SRB2, SRB3, SRB(3)’, SRB(3)" and SRB(4). The constitutional formulae of two of these alkaloids, schumannificine (SRB ) 4 -138 and N-methylschumannificine (SEB(3) 147, have been shown to be new linear tetracyclic compounds with ring D being piperidine in nature on the basis of the chemical evidence and spectral analyses. SRB(2) has been shown to be identical in physical and spectral properties with the product of dehydrogenation of schumannificine (SRB(4) which was named dehydroschumannificine 142. The synthesis of dehydroschumannificine 142 was attempted , This was done in order to correlate the structure that was assigned to it with the natural alkaloids, schumannficine 138and N-methylschumannificine 147, but only the first intermediate, 2,4,6-trihydroxynicotinophenone no 146 was obtained. It was characterised by its spectral properties. The spectral properties of SEB(2)' and SEB(3)" are discussed briefly arid since no conclusive work has been done on then they are tentatively assigned structures 148 & 149 respectively on the basis of their spectral, data.Item INITIAL STAGES AND SOME CHARACTERISTICS OF WEST AFRICAN LINE SQUALLS(1983-03) ADEDOYIN, J. A.A review of West African synoptic weather pattern reveals that the sub-region experiences a special kind of atmospheric disturbance -the line squall - whenever the south-westerlies cover, approximately, the whole of Nigeria. Various methods that have been used to study the squalls (i.e. observational investigations, satellite investigations and modelling) have not been very successful in isolating the trigger mechanism of the phenomenon. It is been proposed that line squalls are initiated through the amplification (with time) of any wave-like perturbation along the surface of discontinuity between the south-westerlies and the north-easterlies. The amplifying perturbations could block the 650 mb. mid-tropospheric jet which further distorts the 'bump' formed by the undulating perturbation. This distortion forces the southwesterlies further up and they could condense. The precipitates fall into the underlying, dry jet and some of them evaporate; the latent heat of evaporation being supplied by the jet. The jet, now cooler, sinks. On sinking, the jet could hit the surface of the earth on which it forms the squall front and crawls; thereby lifting the south-westerlies ahead of it. The cycle of condensation, evaporation and sinking then continunes. A gravity-wave model of this mechanism is presented through the solution of a frequency equation with the aid of a two-layer atmospheric model. The solution is an eigenvalue problem from which many modes of different growth rates and phase velocities could be obtained. Some of these phase velocities will be complex - the real part representing the phase velocity while the imaginary part represents the amplification. Waves with the largest amplifications (i.e. the largest imaginary part) are those that could possibly block the 650 mb. mid-tropospheric jet and trigger off line squalls. Among others, this proposal on the trigger mechanism of line squalls is able to explain: (i) the preference of highlands as places of origin of line squalls, (ii) the close association between the speeds of propagation of line squalls and the mid-tropospheric jet and (iii) the observed overturning of the atmosphere after the passage of line squalls.