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Behavioural adaptations to moisture as an environmental constraint in a nocturnal burrow-inhabiting Kalahari detritivore Parastizopus armaticeps Peringuey (Coleoptera: Tenebrionidae)
O.A.E Rasa
Koedoe : African Protected Area Conservation and Science , 1994, DOI: 10.4102/koedoe.v37i1.326
Abstract: The nocturnal desert detritivore Parastiz.opus armaticeps shows differences in surface activity patterns and burrow fidelity depending on surface humidity. After rain approximately half of the beetle population, independent of sex, is highly vagile and disperses over long distances. During drought, beetles are more sedentary and show higher burrow fidelity. They also inhabit burrows that are longer and deeper than non-inhabited ones, such burrows being relatively scarce. Burrow fidelity and the adoption of a more sedentary habit during drought are considered strategies to avoid the risks of not locating a suitable burrow before sunrise and subsequent desiccation in shallow burrows.
Reproduction in the yellow mongoose revisited
O.A.E. Rasa,B.A. Wenhold,P. Howard,A. Marais
African Zoology , 2012,
Abstract: ENGLISH ABSTRACT: Previous reports on female reproduction in yellow mongooses, based on anatomical examination of specimens, concluded that this species is monoestral but with an extended breeding period. Our long-term studies on known females provide clear evidence of the production of two litters annually within a period of 2-4 months, females initiating a new oestrus cycle while still lactating. We present a biological explanation for the adaptive significance of polyoestry in this species based on a unique mode of infant nutrition for viverrids. ******* AFRIKAANSE OPSOMMING: Anatomiese ondersoeke van volwasse vroulike geelmuishonde het aangetoon dat dit 'n mono-estrusspesie is met 'n verlengde teelperiode. Ons langtermynstudie van bekende wyfies toon dat daar jaarliks twee werpsels binne 'n periode van 2-4 maande geproduseer word waar die wyfies 'n tweede estrussiklus tydens laktasie ondervind. 'n Biologiese verklaring vir hierdie verskynsel is gebaseer op die wyse waarop die kleintjies in die spesie gevoed word. Die manier van voeding is uniek aan die Viverridae
Youth Participation in Rural Development Projects in Surulere Local Government Area of Oyo State, Nigeria
E. Ayanwuyi,O.A. Akinboye,O.A. Olaniyi
The Social Sciences , 2013,
Abstract: The study was carried out in Surulere Local Government Area of Oyo State primarily to assess the youths level of participation in rural community projects. The study identified the type of rural community development projects in which youths participated, various types of contribution of rural youth to community development projects, problems encountered by youth in community developments and to determine the level of contribution of youth to community developments projects. Multistage sampling techniques was used. Firstly, purposive sampling technique was used to select ten rural based community from 5 cells out of the eight cells in one block of the study area. Secondly, 2 villages was purposively selected from each cells where ten respondents were selected for the study. Data was collected with the use of well structured interview schedule while data collected was subjected to descriptive and inferential statistical analysis. The findings revealed that a larger proportion of the respondents were educated farmer, participated in road construction and maintenance and contributed at different level of rural community development. However, problems that prevents youths from participating fully in rural development projects was identified as fund mismanagement, low price of agriculture produce, lack of government assistance and land dispute and rivalry among community leaders. Statistical analysis performed revealed that there was significant relationship between respondents personal characteristics and their level of participation in community development projects.
Corrosion Behavior of 18/8 Stainless Steel and Nickel-Plated Low Carbon Steel in Cassava Fluid  [PDF]
O.O. Oluwole, P.O. Atanda, O.A. Odekunbi, E. Odegbaju
Journal of Minerals and Materials Characterization and Engineering (JMMCE) , 2009, DOI: 10.4236/jmmce.2009.810069
Abstract: This research work investigated the corrosion resistance of nickel- plated medium carbon steel and 18/8 stainless steel in cassava fluid (i.e. containing hydrogen cyanide). It simulated the effect of continuous use of the materials in a cyanide environment where corrosion products are left in place. Low carbon steel sample was nickel electroplated at 4V for 35 minutes. The plated sample, the unplated and the 18/8 stainless steel were then subjected to a cassava fluid environment for thirty days. The electrode potentials, in mV (SCE), were measured every day. Weight loss was determined at intervals of 5 days for duration of the exposure period. The result showed little corrosion attack on the nickel-plated steel on the fifth and tenth days which quickly dropped to zero by the 15th day and remained at the passive state till the 20th day when corrosion picked up again increasing steadily, linearly until the end of the test day. Corrosion of the 18/8 stainless steel was very low as well decreasing till the last day of the test. The pH of the cassava solution which initially was acidic because of the cyanide content in the cassava was observed to progress to neutrality within five days and to alkalinity at the end of the thirty days test (because of corrosion product contamination of the cyanide). Un-plated steel was found to be unsuitable for the fabrication of cassava processing machinery because of the very high corrosion rate. 18/8 stainless steel was found suitable for use in this environment. The renewed corrosion activity on nickel plated steel after the 20th day (pH=12) of continuous use in cyanide environment makes it unsuitable for use.
Evaluation of the Compressive Strength of Hybrid Clay Bricks  [PDF]
O. Azeez, O. Ogundare, T.E. Oshodin, O.A. Olasupo, B.A. Olunlade
Journal of Minerals and Materials Characterization and Engineering (JMMCE) , 2011, DOI: 10.4236/jmmce.2011.107046
Abstract: This work has presented the evaluation of the compressive strength of hybrid clay bricks from interlocking brick making machine. The mixture of clay and cement at varying proportions was loaded into the mould compartment, mechanically rammed and hydraulically controlled. The raw clay was sourced from Ilesa and Akure in the south-western part of Nigeria. The results showed that when the cement content was 6%, the highest compressive load and energy at break were obtained in hybrid bricks from both Ilesa and Akure samples. However, the optimum service performance under compressive loading was attained at 6% cement in Ilesa hybrid bricks. Ilesa hybrid bricks possess better reliability and workability under loading than the Akure bricks.
Control of Traffic Congestion in a Packet-Switching Network Using Routing Algorithms
O.A. Afolabi,E.O. Justice,O.A. Isola
International Journal of Soft Computing , 2012,
Abstract: This research discussed the application of routing algorithms to the control of the congestion of the traffic of packets in a packet-switching network, it is required to find the path with the least total cost of transmitting the packets, with the shortest possible distance between a packet source and a destination host and also to reduce the amount of time that takes the packet to get through to its destination. The routing algorithms considered are Dijkstra algorithm and the Floyd s algorithm, they are reviewed, implemented and compared with respect to there performances. The Floyd s algorithm implementation tends to find the path between all pairs of nodes in the network according to the changes in the costs of each path due to the packet passing through them. This makes Floyd s algorithm implementation one of the best ways of find paths through a network compared to the Dijkstra algorithm implementation which is good particularly for path finding between two specific nodes in the network.
Effect of Tillage Systems and Different Fertilizer Rates on Growth Parameters and Fruit Yield of Okra (Abelimoscus Esculentus)
S.O. Afolayan,O.A. Oladapo,O.A. Akintola,E.F. Muibi
Agricultural Journal , 2013,
Abstract: The interactions between tillage techniques and fertilization play a major role in determining the sustainability of production of okra. Fields experimental were studied in 2004 and 2005 respectively to determine the effect of tillage methods and fertilizer application on crop growth and fruit yield of okra. Three different tillage methods: Ridging (R) Harrowing (H) and Bedding (B) in combination with three fertilizer sources: Control- no fertilizer-S1, NPK (20-10-10) -S2 , Urea (45,0,0)-S3 and 0rgano-mineral (2.25, 0.89, 2.01)-S4 were considered for the first year. The second year experiment retained the tillage systems but adopted the best fertilizer source of the first year at four different rates 0 kg ha 1 (F1), 200 kg ha 1 (F2), 300 kg ha 1 (F3) and 400 kg ha 1 (F4). Soil properties were conducted before and after the experiments. Growth indices such as Number of Leaves (NL), Plant Height (PHT), Stem Diameter (SD) and Leaf Area (LA) were measured. Results obtained revealed that there were no significant differences (p< 0.05) in bulk density (R = 1.29 gm cm 3, p = 1.40 gmkm3, H = 1.44 g km3, B = 1.45 gm cm 3) conducted after the first season. However, cone penetration resistances were greatly influenced by tillage methods (p = 0.065 kg s 1, R = 0.93 kg s 1, H = 0.93 kg s 1, B = 0.95 kg s 1). There were significant differences in all the crop growth and fruit yields of the two seasons. In the first year, S4 fertilizer source in combination with R had the best mean leaf area followed by S2 fertilizer source in combination with H. S1R, S2R and S4R appeared most stunted in growth at p< 0.05. Generally, S3 fertilizer source combined with H tillage method (S3H) recorded the highest mean yield at 2.4/ha followed by S2H at 2.3t ha 1. The second year experiment recorded significant differences (p< 0.05) among the treatments in growth and fruit yield. F3P produced the highest mean PHT (744.33 mm), F2B had the best NL and F3B producing best robust plants in terms of SD, F1B appeared to be the treatment with the most luxuriant canopies respect to LA and F2P having the highest mean yield at 5.53t ha 1. Overall result showed that 200kg ha 1 of NPK fertilizer in combination with ploughing (F2Pi) was suggested as the best treatment option for the sustainable cultivation of okra.
Effects of Cigarette Tobacco Infusion on Root Regeneration and Proliferation of Two Cultivars of Garden Croton (Codiaeum variegatum)
O.A. Alabi,O.A. Akinbami,K.O. Ogunwenmo,E.B. Esan
Asian Journal of Plant Sciences , 2010,
Abstract: Garden croton, an ornamental shrub or tree with diverse beautifully colored leaves, shapes and sizes, is used as informal hedge or screen for landscape, interiorscape and bouquet. This study, investigated the effects of cigarette tobacco extract on plant mutation, root regeneration and proliferation in a plant-plant interactive hydroponic assay using two well known reciprocal mutant cultivars (Guinea broad leaf and Guinea narrow leaf) of garden croton. The results showed that 1x10-(4-8) logarithm dilution of a standard teacup (270 mL) cigarette tobacco-infusion enhanced root regeneration, elongation and proliferation above control level. Higher concentrations of extract inhibited root elongation and proliferation. Undiluted tobacco infusion extract (100%) delayed root initiation until four weeks. Overall, the extract enhanced root elongation and proliferation better in the Guinea broad leaf than the Guinea narrow leaf cultivar. There was no sign of induced mutation in the plant cultivars by the extract.
Epistaxis in Sagamu
O.A Sogebi, E.A Oyewole, O.A Adebajo
Nigerian Journal of Clinical Practice , 2010,
Abstract: Epistaxis is a common nasal complaint with varied aetiologies. Physicians need to know the characteristics of epistaxis in their area of practice in order to give the best amongst the various treatment options.The aimof this studywas to analyze the causes,management and outcome of epistaxis in Sagamu This is an analysis of the patients who had epistaxis and were managed in the Ear, Nose and Throat department of Olabisi Onabanjo University Teaching Hospital in Sagamu, Ogun state between July 2003 and June 2007. Therewere seventy-nine patients M:F ratiowas 1.3:1. Therewere two peak age groups between 1- 10 and 31-40, with a mean age of 34.8 years. Anterior epistaxis was present in 60.8%, 11.4% had posterior, 5.1% had combined anterior and posterior,while the location of the bleeding could not be ascertained in 22.8% of the patients. The leading causes noted were idiopathic 29.1%%, road traffic accidents 24.1%, sinonasal and nasopharyngeal malignancies 22.8%. 77.3% of the patients had their epistaxis controlled with nasal packs, with 72.2% of the nasal bleeds being well controlledwithout complications. 2.5% of the patients had recurrent epistaxis and 1.3% died. The trend of epistaxis in our study is in agreement with that found in previous studies. Nasal packingswere effectivemethods of treatment.
Persistence of Rhizobium inoculants originating from Leucaena leucocephala fallowed plots in Southwest Nigeria
O.A. Ojo, O.E. Fagade
African Journal of Biotechnology , 2002,
Abstract: Ten core soil samples were collected from experimental plots at IITA, SW Nigeria that were previously inoculated with Rhizobium strains (IRC1045 and IRC 1050) specific for Leucaena leucocephala at two depths; 0—15 cm and 15—30 cm. The control soil samples were collected at similar depths from an adjacent field with no previous history of legume cultivation. Six weeks after planting of L. leucocephala in the soil samples in the greenhouse shoots, roots and nodules were harvested aseptically. Typing of the nodules as well as the identification of the persisting population of the introduced strains were based on the intrinsic resistance of IRC 1045 and IRC 1050 to streptomycin at 500 mg/ml and nodules were found to be made up of 100% of previously introduced strains. The potency and competitive ability of the recovered IRC 1045 and IRC 1050 were thus confirmed via the pot experiment and plant reinfection experiment in the greenhouse. At 0—15 cm and 15—30 cm depths 8.0 x 104 and 9.0 x 104 rhizobia/g of soil were recovered respectively in spite of the 10-year fallow period. Biomass production with the three woody legumes revealed Root and Shoot dry weights of the following order of magnitude Senna siamea > L. leucocephala > Senna spectabilis. This report showed the great potential of application of Rhizobium technology in low input sustainable agricultural practice and environmental pollution abatement for non-use of chemical nitrogen fertilizers. (African Journal of Biotechnology: 2002 1(1): 23-27)
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