Showing papers by "University of Nigeria, Nsukka published in 1976"
TL;DR: The nitrogen and phosphorus contents of organic materials as a factor in determining the trend of mineralization of these elements when plant materials are added to the soil, were studied in an incubation experiment over a period of 12 weeks as mentioned in this paper.
Abstract: The nitrogen and phosphorus contents of organic materials as a factor in determining the trend of mineralization of these elements when plant materials are added to the soil, were studied in an incubation experiment over a period of 12 weeks. Nitrogen mineralization increased with decreasing C:N ratio. No nitrogen mineralization was recorded above C:N ratio of 16.1 and the critical ratio lay between this and 23.0, with the plant materials used. Initial phosphorus immobilization occurred when plant materials ranging in C:P ratio from 501 to 112 were decomposed in the soil. The release of the immobilized phosphorus as incubation progressed suggests that green manuring should be considered of long-term benefit as far as phosphorus is concerned.
75 citations
TL;DR: The physiological and biochemical mechanisms involved in the formation of the egg-shell while conserving resources lead to the emergence of unique structural properties in the eggshell, providing for the developing embryo a self-contained and precisely regulated environment.
Abstract: Publisher Summary This chapter discusses the physiological aspects of reproduction in nematodes. A general survey of the range of reproductive phenomena in the Nematoda indicates that all the main cytogenetic mechanisms observed in the animal kingdom are apparently represented in this phylum. In the pursuit of reproductive efficiency, there has been an elaboration of the reproductive systems, particularly in the parasitic members, such that greater histological and cytological differentiation has engendered precise and, perhaps, unique physiological mechanisms that ensure a successful fertilization and development of the embryo. In particular, the physiological and biochemical mechanisms involved in the formation of the egg-shell while conserving resources lead to the emergence of unique structural properties in the eggshell, providing for the developing embryo a self-contained and precisely regulated environment. The great success of nematodes as parasites is derived mainly from their ability to maintain reproductive efficiency with little morphological specialization while retaining at the same time some capability for biological variation in ontogeny.
65 citations
TL;DR: In this paper, the design, construction and development of a continuous-process mechanical peeler for cassava processing is described, which consists of a cylindrical knife assembly and a solid cylinder, both mounted parallel and 20 mm apart on an inclined frame.
24 citations
Journal Article•
TL;DR: In this article, the authors evaluated the textural and petrographic attributes of sandstones of several Cretaceous formations of southern Nigeria sedimentary basin have been evaluated and found that nearness of the Abakaliki basin to the source region of Cameroun basement complex was the governing factor in the survival and accumulation of feldspars in the sand of the first cycle.
Abstract: Textural and petrographic attributes of sandstones of several Cretaceous formations of southern Nigeria sedimentary basin have been evaluated. Sandstones of the first sedimentary cycle (Albian-Santonian) confined mainly to the Abakaliki basin are feldspathic and those of the second sedimentary cycle (Campanian-Eocene) confined mainly to the Anambra-Afikpo basin are quartz arenites. Nearness of the Abakaliki basin to the source region of Cameroun basement complex was the governing factor in the survival and accumulation of feldspars in the sand of the first cycle. Although detritus of the second cycle was derived from the same source region, it underwent intense chemical weathering in a humid climate and during long transportation to the Anambra site of deposition, and thereby attained a high degree of mineralogical maturity. In both cases, duration of erosion played a critical role in the presence or absence of feldspar in sediments. Quartz arenites with low textural index are perhaps indicative of a miogeosynclinal deposition whereas texturally mature quartz arenites are characteristic of cratonic or stable platform. Fragmentation of large polycrystalline quartz grains into finer subindividuals in a dynamic environment is advanced as an adequate mechanism to account for the origin of fine and silt-size particles in a sedimentary system.
22 citations
TL;DR: In this paper, the extent of sulphur deficiencies in the soil in Nigeria was investigated using greenhouse experiments, and the results showed that the soils with low buffer capacity are more likely to respond to sulphur application than soils with high buffer capacity.
20 citations
TL;DR: The Stanford Watershed Model was tested on two Nigerian watersheds and it was shown that model parameters for ungaged streams may be correlated on a regional basis from parameters of nearby gaged streams as mentioned in this paper.
Abstract: The Nigerian version of the Stanford Watershed Model was tested on two Nigerian watersheds. It was shown that model parameters for ungaged streams may be correlated on a regional basis from parameters of nearby gaged streams.
18 citations
TL;DR: In this article, the phonon-phonon half-widths have a strong dependence on the temperature and magnitude of the stackrel, but are roughly independent of the direction of thestackrel.
Abstract: Phonon decay rates in potassium due to phonon-phonon and electron-phonon scattering are calculated and compared for small wave numbers at low temperatures (\ensuremath{\sim}1 to 10 K). We find that the phonon-phonon half-widths ${\ensuremath{\Gamma}}_{\mathrm{pp}}$ have a strong dependence on the temperature and magnitude of $\stackrel{\ensuremath{\rightarrow}}{\mathrm{q}}$, but are roughly independent of the direction of $\stackrel{\ensuremath{\rightarrow}}{\mathrm{q}}$. The electron-phonon half-widths ${\ensuremath{\Gamma}}_{\mathrm{ep}}$ are temperature independent, vary slowly with $q$ (linear in $q$ for $q\ensuremath{\lesssim}0.3\ifmmode\times\else\texttimes\fi{}\frac{2\ensuremath{\pi}}{a}$), and have a strong directional dependence on $\stackrel{\ensuremath{\rightarrow}}{\mathrm{q}}$ for the transverse phonon modes. The umklapp contribution ${\ensuremath{\Gamma}}_{\mathrm{pp}}^{U}$ to the total phonon-phonon decay rate ${\ensuremath{\Gamma}}_{\mathrm{pp}}^{\mathrm{TOT}}$ is also calculated for small $q$ and is shown to have a pronounced temperature dependence whereby $\frac{{\ensuremath{\Gamma}}_{\mathrm{pp}}^{U}}{{\ensuremath{\Gamma}}_{\mathrm{pp}}^{\mathrm{TOT}}}$ decreases rapidly at lower temperatures. In comparing the various half-widths we find that at high temperature (\ensuremath{\gtrsim} 30 K) ${\ensuremath{\Gamma}}_{\mathrm{pp}}$ dominates ${\ensuremath{\Gamma}}_{\mathrm{ep}}$. At lower temperatures the two are comparable to each other and the situation is complex. Along certain directions in $\stackrel{\ensuremath{\rightarrow}}{\mathrm{q}}$ space for certain branches ${\ensuremath{\Gamma}}_{\mathrm{ep}}$ may dominate whereas along symmetry directions at small $q$ for the transverse branches ${\ensuremath{\Gamma}}_{\mathrm{ep}}$ is zero and ${\ensuremath{\Gamma}}_{\mathrm{pp}}$ dominates. The relevance of these and other results are discussed in the context of low-temperature transport properties. Finally we briefly compare our results for potassium with those for two other simple metals, rubidium and aluminum.
17 citations
TL;DR: A study of the patterns of vocational choice and aspiration of a group of postprimary schools in Nigeria, using a questionnaire schedule, revealed a durable and early crystalization of vocational decision and commitment.
15 citations
TL;DR: Evidence is presented which indicates that the female substance originates in the female reproductive system in certain secretory cells located in the pulvilus while the male substance may be secreted by the male caudal glands.
14 citations
TL;DR: In this paper, the reactions of 2-amino-3-hydroxypyridine and 2-chloro-3 -nitropyridine in various solvents and in the presence of certain catalysts were studied.
11 citations
TL;DR: The incidence of yeast-like fungi on normal skin was investigated in 52 healthy Nsukka individuals comprising 21 adults, 24 children, and 7 infants, and eighty-six isolates of yeasts and 2 of Geotrichum candidum were recovered.
Abstract: The incidence of yeast-like fungi on normal skin was investigated in 52 healthy Nsukka individuals comprising 21 adults, 24 children, and 7 infants. Eighty-six isolates of yeasts and 2 of Geotrichum candidum were recovered. The yeasts included Candida tropicalis — 36 isolates, C. guilliermondii — 3, C. parapsilosis — 2, Candida spp. (unidentified) — 16, Cryptococcus albidus — 6, Trichosporon cutaneum — 7, Trichosporon spp. — 8 and Rhodotorula spp. — 8 isolates. The isolates originated from various sites, predominantly from nails and finger clefts. The significance of the findings is discussed with particular reference to the absence of C. albicans and the frequent isolation of C. tropicalis, T. cutaneum and C. albidus.
TL;DR: In this paper, a Green's function approach is used to formulate and obtain the stress field, under torsional loads in a radially finite solid cylinder with radially variable elastic modulus.
Abstract: A Green's function approach is used to formulate and obtain the stress field, under torsional loads in a radially finite solid cylinder with radially variable elastic modulus. With this approach a certain dual static-geometric analogy in the solution is readily proved and applied to generate the solution with stress boundary conditions from that with displacement boundary conditions and vice-versa. The problem is solved using both boundary conditions and for an exponentially varying shear modulus. In particular, under displacement boundary conditions, the stress field in the solid with a generalised Reissner-Sagoci boundary condition is easily deduced. With stress boundary conditions, the criteria for crack propagation in such elastic models are also obtained using the Griffith-Irwin condition of rupture.
TL;DR: In this paper, a dehumidification system was designed to draw moist air through a bed of sorbent which absorbed moisture from the air to yield air of lower relative humidity.
TL;DR: Pot experiments were carried out to investigate the real effects of Dalapon and Amionotriazole herbicides on the development of mycorrhiza in seedlings of P. sylvestris, and both adversely affected mycotrophy, confirming their toxic tendency shown in earlier in vitro experiments.
Abstract: Pot experiments were carried out to investigate the real effects of Dalapon and Amionotriazole herbicides on the development of mycorrhiza in seedlings of P. sylvestris. Despite their different toxicity, both adversely affected mycotrophy, confirming their toxic tendency shown in earlier in vitro experiments. It is consequently suggested that much consideration should be given to choice of herbicides, as mycorrhiza forming fungi, as well as ectotrophic mycorrhizae, are sensitive to these toxicants.
TL;DR: SAR arcs were observed from Southern Africa on 17/18 December 1971, 4/5 August 1972 and 1/2 April 1973 with the equatorwards edge at L = 1.8.
TL;DR: A survey of the chemical literature recently undertaken by us, has revealed that much greater attention is being given nowadays to organo-sulfur compounds as discussed by the authors, and many of them were isolated from coal, 3 plant, animals' and soil microbes.
Abstract: A survey of the chemical literature recently undertaken by us, has revealed that much greater attention is being given nowadays to organo-sulfur compounds. New products containing sulfur have emerged and many of them were isolated from coal, 3 plant, animals' and soil microbes. 6 A great majority of them are, however, man-made and are obtained by intricate but often exciting synthetic procedures which give rise to new reactions, new chemistry and a great variety of potentially useful chemical compounds. These studies led to the synthesis of derivatives of phenothiazine (1)7 the sulfur analog of phenoxazine, and to dithieno(2,3-b: 2′,3′-e)(l,4)thiazine (2)′, cyclopental(1,2-b: 4,3-bf)-dithiophene (3)9 and benzothienoacridine (4) derivatives which are thiophene analogs of phenothiazine, fluorene and benz(c)acridine respectively.
TL;DR: Adequate measures should be taken to minimize adverse effects of the projects on the public health, as such water resources development may increase the incidence of Schistosomiasis, Malaria, Onchocerciasis, and TrypanosOMiasis.
Abstract: . The Governments of Nigeria have planned to build 395 dams in the next five years. Such water resources development may increase the incidence of Schistosomiasis, Malaria, Onchocerciasis, and Trypanosomiasis. Adequate measures should be taken to minimize adverse effects of the projects on the public health.
TL;DR: A pamphlet war as puritan propaganda sought to force a reappraisal of the Anglican Church's religious settlement included the codification of the canons which gave definition and cohesion to the church and reformed her adminstrative machinery as discussed by the authors.
Abstract: King James I's reign was a landmark in the history of the Anglican Church. His religious settlement included the codification of the canons which gave definition and cohesion to the church and reformed her adminstrative machinery. But this touched off a pamphlet war as puritan propaganda sought to force a reappraisal of the settlement. They alleged that bishops harassed and deprived hard-working, conscientious, loyal clergymen who merely rejected the ceremonies. The bishops employed young apologists to discredit the opposition and plead for conformity. They claimed that only thirty to sixty puritan clerics were deprived.
TL;DR: An energy-dependent polymerization-depolymerization phenomenon in the beta-glucosidase (beta-D-glUCoside glucohydrolase, EC 3.2.1.21) in the gut contents of the giant African snail Achatina achatina has been observed.
TL;DR: Calcium ethylenediaminetetraacetate (CaEDTA) was found to induce definite ultrastructural changes in the rat kidney, when infused intravenously at toxic doses (6 mmoles/kg/24 h).
TL;DR: In this paper, the authors investigated the problem of using quaternionic scalar fields as Higg's mesons in theories of spontaneously broken symmetries and were led to the symplecticSp(1,Q) ⊗U(1) as a possible gauge group for a unified theory of electromagnetic and weak interactions.
Abstract: We investigate the problem of using quaternionic scalar fields as Higg's mesons in theories of spontaneously broken symmetries. We are led to the symplecticSp(1,Q) ⊗U(1) as a possible gauge group for a unified theory of electromagnetic and weak interactions. The features of this model are worked out and compared with those of Weinberg'sSU(2) ⊗U(1) model.
Journal Article•
TL;DR: The value of finding out the causative allergen by a detailed case- history and later by a skin-testing against the most probable allergens (as suggested by the case-history)--is stressed.
Abstract: The importance of Allergy in the causation of several important diseases e.g. Asthma, is well known (Voohorst 1962; Voorhorst, Spieska-Beezeman and Spieska 1964-). In this article, the value of finding out the causative allergen by a detailed case-history and later by a skin-testing against the most probable allergens (as suggested by the case-history)--is stressed. The major allergens responsible for the Allergic immunopathies in Nigeria--as found by testing in 50 cases are mentioned. It is hoped that more hospitals will be stimulated to perform skin-testing in view of the encouraging results and responses to de-sensitization so far obtained in different centres practising this procedure.
TL;DR: Light microscope studies showed that Meloidogyne hapla biotype developed within corn root tissue, and although giant cell development occurred mainly in the stele, there was the rare case of giant cell formation in the cortex.
Abstract: Light microscope studies showed that Meloidogyne hapla biotype developed within corn root tissue. Although giant cell development occurred mainly in the stele, there was the rare case of giant cell formation in the cortex. Giant cells contained several nuclei, either scattered or in clusters; cytoplasm of the giant cells was dense and cell walls thickened.
TL;DR: Furthermore, in spite of its potential and importance in terms of its working force and its contribution to the gross domestic product, of the estimated private sector investment amounting to about £816 million, during the 1970-1974 plan period, only £123 million or 15 per cent was estimated investment expenditure by the rural sector as discussed by the authors.
Abstract: Furthermore, in spite of its potential and importance in terms of its working force and its contribution to the gross domestic product, of the estimated private sector investment amounting to about £816 million, during the 1970-1974 plan period, only £123 million or 15 per cent was estimated investment expenditure by the rural sector (3). And of the £780 million planned public investment, only about £140 million or 18 per cent was for direct or indirect investment in the rural areas, as the following table shows :
TL;DR: In this paper, the authors extend JureckovS's (1969) results to the case where the initial randan variables nay not be identically distributed, and show that the result holds even when the initial variables are not identical.
Abstract: This note extends JureckovS's (1969) results to the case where the initial randan variables nay not be identically distributed.