1,193 research outputs found

    Development of micropropagation system for yam (Dioscorea spp.) using somatic embryogenesis

    Get PDF
    Inadequate availability of disease-free planting materials remains a major constraint to yam production. The tissue culture technique has been used to regenerate disease-free plantlets from pre-formed, heattreated meristems followed by micropropagation. This procedure, however, has a low multiplication ratio with an average of 1: 4 every eight weeks. Embryo production from somatic cells (somatic embryogenesis, SE) is a system in which each somatic cell can regenerate a complete plantlet. However, previous reports show low SE induction frequencies and significant variations in success rates among different genotypes while hardly any report exist for improved varieties that farmers desire, especially in Nigeria. Studies were carried out to evaluate the effects of different plant growth regulators (PGRs) on induction of somatic embryogenesis of the following genotypes: one improved Dioscorea alata (TDa 291) and three improved (TDr 95/19177, TDr 89/2665, TDr 95/18544) and one landrace (Obioturugo) of Dioscorea rotundata. Leaf, stem, and axillary bud explants were cultured in MS basal medium containing fifteen treatment combinations of 2,4-Dichlorophenoxyacetic acid (2,4-D), Naphthaleneacetic acid (NAA), Benzylaminopurine (BAP), Picloram, and Uniconazole-P (UP). The genotype TDr 95/19177 was tested for SE in Temorary Immersion Bioreactor System (TIBS). The incidence of induction of callus formation and plantlet regeneration from the three explants were recorded. Embryogenic callus induction was highest (87%) from axillary buds cultured on modified MS + 2 mg/l of 2,4-D + 1 mg/l of NAA while 1 mg/l of BAP + 9. 9 mg/l of UP had the highest percentage plantlet regeneration of 50% in TDr 95/18544 and an average of 37% across genotypes at a mean of 5 plantlets per explant. The genotype TDr 95/19177 was successfully regenerated via indirect somatic embryogenesis in the SETIS Type Temporary Immersion Bioreactor System

    ADAPTING MODERN METHODS OF LECTURING IN NIGERIAN UNIVERSITIES: A CRITIQUE

    Get PDF
    Different disciplines have explored the concept of lecturing from different perspectives. However, adapting some modern methods of lecturing in Nigerian universities have not been systematically studied.   Therefore, this paper examines critically the modern   methods of lecturing in our modern days tertiary institutions in Nigeria.In agreement with other researches, this paper notes that there are many challenges facing the   methods of teaching in Nigerian Universities today. Triangulation method was used to gather information for this paper, and both primary and secondary   sources were used to obtain information for this article.  The findings of this paper show that the traditional lecture method will not lead to much educational achievements unless it is combined with interactive engagements with the students and prompt feedback from the tutorsThe paper recommends that if Government could live up to her   expectation by provision of basic amenities and   state-of-the-arts teaching facilities to the tertiary institutions, the phenomenon could be reduced. A concerted effort is therefore needed among all stake holders in the education sector for the task of promoting effective teaching in our tertiary institutions

    Seed yam production in an aeroponics system: a novel technology

    Get PDF

    Retirement And Adjustment Levels: A Case Study Of Retirees In Ogun State

    Get PDF
    This study examined the level of adjustment (positive or negative) of retirees in Ogun State, Nigeria, as well as their perception (positive or negative) of retirement and the level of adjustment. A self-developed questionnaire was used for data collection. The subjects for the study were 72 retirees (34 males and 38 females), drawn from public, private and government owned companies in Ogun State. Results of the study revealed that respondents had positive perception of retirement and positive level of adjustment in retirement.  The relationship between perception and level of adjustment was not statistically significant [p > 0.05] which indicates that factors other than perception contribute to the positive level of adjustment of the respondents.  &nbsp

    Chest X-ray findings in HIV- infected Highly Active Antiretroviral Treatment (HAART) - naïve patients

    Get PDF
    Introduction: Patients with human immunodeficiency virus (HIV) infection frequently present with a wide spectrum of pulmonary and cardiaccomplications from the virus, opportunistic infections and neoplasms that may be associated with a high mortality rate. Diseases of the respiratorytract account for about half of deaths from AIDS, while cardiac diseases account for more than a quarter of deaths from AIDS. This study aimed atdetermining the prevalence of pulmonary and cardiac diseases using a chest radiograph in HAART-naïve HIV-infected patients. Methods: Thisstudy was conducted at Lagos State University Teaching Hospital (LASUTH) HIV clinic between September 2010 and August 2011 amongst allregistered HAART-naïve HIV/AIDS patients. Patients had posterior-anterior chest radiographs done in full inspiration. Participants were asked andaided to fill the structured questionnaires to obtain demographic data. Results: Out of a total of one hundred and two recruited for the study, 54 (52.94%) had a normal chest radiograph, while 48 (47.06%) had abnormal chest radiograph .The abnormal findings included, 27.45% who hadbronchopneumonia, 6.86% cardiomegaly, 5.88% pulmonary tuberculosis, 5.88% radiological features of congestive cardiac failure, and 0.98%bronchitis. Conclusion: It appears that more than half of HAART–naïve HIV-infected patients have normal chest radiographs. Bronchopneumonia(27.5%) is the commonest pulmonary abnormality associated with HIV infection, while the prevalence of pulmonary tuberculosis is 5.88%.Key words: Chest X-ray, HIV-infected, HAART-naïve

    IMPROVE:Identifying Minimal PROfile VEctors for similarity based access control

    Get PDF
    There is ample evidence which shows that social media users struggle to make appropriate access control decisions while disclosing their information and smarter mechanisms are needed to assist them. Using profile information to ascertain similarity between users and provide suggestions to them during the process of making access control decisions has been put forth as a possible solution to this problem. This paper presents an empirical study aimed at identifying the minimal subset of attributes which are most suitable for being used to create profile vectors for the purpose of predicting access control decisions. We begin with an exhaustive list of 30 profile attributes and identify a subset of 2 profile attributes which are shown to be sufficient in obtaining similarity between profiles and predicting access control decisions with the same accuracy as previous models. We demonstrate that using this pair of attributes will help mitigate the challenges encountered by similarity based access control mechanisms

    Non-sharing communities?:an empirical study of community detection for access control decisions

    Get PDF
    Social media users often find it difficult to make appropriate access control decisions which govern how they share their information with a potentially large audience on these platforms. Community detection algorithms have been previously put forth as a solution which can help users by automatically partitioning their friend network. These partitions can then be used by the user as a basis for making access control decisions. Previous works which leverage communities for enhancing access control mechanisms assume that members of the same community will have the same access to a user’s content, but whether or to what extent this assumption is correct is a lingering question. In this paper, we empirically evaluate a goodness of fit between the communities created by implementing 8 community detection algorithms on the friend networks of users and the access control decisions made by them during a user study. We also analyze whether personal characteristics of the users or the nature of the content play a role in the performance of the algorithms. The results indicate that community detection algorithms may be useful for creating default access control policies for users who exhibit a relatively more static access control behaviour. For users showing great variation in their access control decisions across the board (both in terms of number and actual members), we found that community detection algorithms performed poorly

    Comparison of the EMG Activities in the Vastus Medialis Oblique and Vastus Lateralis Muscles During Hip Adduction and Terminal Knee Extension Exercise Protocols

    Get PDF
    The purpose of this study was to compare the electromyographic (EMG) activities in the vastus medialis oblique (VMO) and vastus lateralis (VL) muscles during two open chain exercises commonly used in the management of patellofemoral pain syndrome (PFPS). Twenty-five (14 female and 11 male) healthy subjects participated in the study. The A 2 (testing condition) x 2 (exercise type) x 2 (gender) quasi-experimental design was employed. Using surface electrodes, the EMG activities in the VMO and the VL muscles during ten repetitions of hip adduction and terminal knee extension exercises were recorded. The order of presentation of the experimental conditions was randomized. The three-way repeated ANOVA revealed no significant main effects for testing conditions, exercise type or gender, but the terminal knee extension exercise type x gender interaction effect was statistically significant (F= 8.28,

    Novelty, rapidity and quality in seed yam production: the case of Temporary Immersion Bioreactors

    Get PDF

    Ovarian vein thrombosis in a polytrauma patient

    Get PDF
    A young mother presented to a Major Trauma Centre (MTC) following a road traffic collision. Her admission computed tomography (CT) traumagram demonstrated liver and renal lacerations, spinal and pelvic fractures with no abnormalities of the ovarian veins. Her inpatient course was uncomplicated other than a sustained, isolated raised c-reactive protein (CRP). CT abdomen one week after injury demonstrated stable solid organ injuries and the additional, unexpected finding of a right ovarian vein thrombosis (OVT). A pragmatic approach was taken towards the management of the OVT given the haemorrhagic risk from her traumatic injuries. A multi-disciplinary, consultant-led plan was made to slowly increase enoxaparin to a therapeutic dose under close surveillance and to then switch to warfarin following an outpatient consultation with a consultant haematologist. A magnetic resonance venogram was performed after 3 months of anticoagulation and this demonstrated complete resolution of the OVT and normal appearances of the ovary
    corecore