Trends and Future Directions in Open and Distance Learning Practice in Africa

Open and Distance Learning (ODL), formerly known as Distance Education (DE) is one of the most rapidly growing fields of education in recent time. Distance education has experienced remarkable growth in national and international scenes since the early 1980s. In spite of recent phenomenal developments in the world of electronic networks, especially the recent global attention to the Internet, which has provided the primary technological thrust, several other emerging technologies have also promised to change the landscape of education in general, and distance education in particular drastically. The field of distance education is therefore, at the centre of dynamic growth and change. This paper focuses on current trends in ODL from African perspective. It examines some of the definitions that have been put forward by experts in the field, as well as some features that characterized ODL. The paper also reflects on some practices in Africa’s ODL programmes. Furthermore, current trends in the practice of ODL in African countries like South Africa, Zimbabwe, Tanzania, Bostwana and Nigeria are critically discussed. Some of the policy recommendations highlighted in the paper include the need to invest more in ODL through meaningful budgetary allocations and cost sharing at higher levels of education, creation of partnerships and networking among ODL institutional providers within the continent, private telecommunication sector, and Non Governmental Organizations (NGOs)

Radiographic studies on morphological anomalies in artificially spawned Heterobranchus longifilis Valenciennes, 1840 F1 generation

This study was designed to examine radiographically the morphological anomalies in artificially spawned 24-week-old Heterobranchus longifilis. A total of 22 morphological deformities observed from an F1 population of 4,871 were classified. Based on anatomical positions, most of the anomalies (49.99%) manifested in the bodies as stunted growth with a weight range of 240-358g, standard length (SL) of 18.7-29.1cm and stump body trait with a weight range of 445-810g, SL of 22.9-35.9cm. Anomalies of the vertebral column accounted for 27.27% with a weight range of 410-945g, SL of 27.4-36.8cm. Fin aberrations including agenesis were seen in 22.73% with a weight range of 548-840g, SL of 34.1-39.2cm. Radiographic examination revealed anomalies such as hypoplasia and hyperplasia of fins, supernumeracry and agenesis of fins, fin cleft, and fusion of fins, scoliosis and kyphosis. The phenotypic lateral body curvatures and stump body trait were basically due to varying degrees and positions of scoliosis and thus, pathological. The fin aberrations and agenesis were probably congenital. The anomalies affected feed accessibility; thus; impaired the growth of the fishes evidenced by the low body weights recorded in the deformed fish compared to the normal fish. In conclusion, the percentage of morphological aberrations observed in the F1 population is negligible (0.45%), thus it will not adversely affect production of H. longifilis via artificial induction.Keywords: Artificial induction, Heterobranchus longifilis, Morphological anomalies, Radiograph

Cognitive impairment and decline in cognitively normal older adults with high amyloid-β: A meta-analysis

AbstractIntroductionThis meta-analysis aimed to characterize the nature and magnitude of amyloid (Aβ)-related cognitive impairment and decline in cognitively normal (CN) older individuals.MethodMEDLINE Ovid was searched from 2012 to June 2016 for studies reporting relationships between cerebrospinal fluid or positron emission tomography (PET) Aβ levels and cognitive impairment (cross-sectional) and decline (longitudinal) in CN older adults. Neuropsychological data were classified into domains of episodic memory, executive function, working memory, processing speed, visuospatial function, semantic memory, and global cognition. Type of Aβ measure, how Aβ burden was analyzed, inclusion of control variables, and clinical criteria used to exclude participants, were considered as moderators. Random-effects models were used for analyses with effect sizes expressed as Cohen's d.ResultsA total of 38 studies met inclusion criteria contributing 30 cross-sectional (N = 5005) and 14 longitudinal (N = 2584) samples. Aβ-related cognitive impairment was observed for global cognition (d = 0.32), visuospatial function (d = 0.25), processing speed (d = 0.18), episodic memory, and executive function (both d's = 0.15), with decline observed for global cognition (d = 0.30), semantic memory (d = 0.28), visuospatial function (d = 0.25), and episodic memory (d = 0.24). Aβ-related impairment was moderated by age, amyloid measure, type of analysis, and inclusion of control variables and decline moderated by amyloid measure, type of analysis, inclusion of control variables, and exclusion criteria used.DiscussionCN older adults with high Aβ show a small general cognitive impairment and small to moderate decline in episodic memory, visuospatial function, semantic memory, and global cognition

Valproic acid is associated with cognitive decline in HIV-infected individuals: a clinical observational study

BACKGROUND: Valproic acid (VPA) is often used to control pain in HIV-related neuropathy. However, the effect of VPA on cognitive functions in advanced HIV-infected individuals is largely unknown. A recent study would suggest that it may have a neuroprotective effect, the doses used were low and the observation period short. METHODS: We used a well studied HIV-infected cohort assessed for a median of 15 (range 6–27 months) to determine whether individuals who were receiving VPA showed any cognitive benefits. Multiple regression procedures allowed us to control for the effects of HAART and HIV disease status as well as numbers of visits and variation in VPA intake over-time. RESULTS: We found a negative effect of VPA (mean dose of 850 mg/d for 18 months on average; range 6–27 months) on cognitive performance in eight advanced HIV-infected individuals compared to 32 advanced HIV-infected individuals on no VPA who had comparable neuropsychological performance at baseline. Control for plasma HIV viral load provided similar results. CONCLUSION: Our results suggest that further studies of VPA in advanced HIV-infection should cautiously include high doses over prolonged periods of at least 18 months in order to more accurately determine whether the posited neuroprotective benefit of VPA still occurs or whether it is replaced by toxicity

Acceptability and usability of computerized cognitive assessment among Australian Indigenous residents of the Torres Strait Islands

Objectives: This cross-sectional study aimed to investigate the acceptability and usability of the Cogstate Brief Battery (CBB) in a community-based sample of Australian Indigenous people from the Torres Strait region, based on a user experience framework of human-computer interaction. Methods: Two-hundred community participants completed the four subtests of the CBB on an iPad platform, during a free adult health check on two islands in the region, between October and December 2016. Acceptability was defined as completing the learning trial of a task and usability as continuing a task through to completion, determined by examiner acumen and internal Cogstate completion and integrity criteria. These were combined into a single dichotomous completion measure for logistic regression analyses. Performance-measured as reaction times and accuracy of responses-was analyzed using linear regression analyses. Results: CBB completion ranged from 82.0% to 91.5% across the four tasks and the odds of completing decreased with age. After adjusting for age, iPad/tablet familiarity increased the odds of completion for all tasks while level of education and employment increased the odds for some tasks only. These variables accounted for 18.0%-23.8% of the variance in reaction times on speeded tasks. Age and education had the most effect, although semipartial correlations were modest. Conclusions: When administered in a health-screening context, the acceptability and usability of the CBB were greatest in young- to middle-aged participants with some education and iPad/tablet experience. Older and more vulnerable participants may have benefited from additional time and practice on the CBB prior to administration

Using health check data to investigate cognitive function in Aboriginal and Torres Strait Islanders living with diabetes in the Torres Strait, Australia

Background: Type 2 Diabetes (T2DM) has a subtle deleterious effect on cognition and imposes a higher lifetime risk of cognitive impairment and dementia. In populations where both T2DM and dementia are highly prevalent, understanding more about the early effects of T2DM on cognition may provide insights into the lifetime risks of this disease. Methods: In 2016, 186 Australian Aboriginal and/or Torres Strait Islander residents of the Torres Strait (54% female, mean age =8.9 years, SD =15.9, range =15–74) participated in a community health check. The effect of diabetes (Type 1 or Type 2) on speed of thinking and working memory was assessed with the Cogstate Brief Battery (CBB) during the health check. Results: One third of participants had diabetes (n = 56, 30.1%). After adjusting for age, education and previous iPad/Tablet experience, participants with diabetes had a small, yet significant reduction in accuracy on the One Back working memory task (β = −.076, p =.010, r2 =.042). The effect was most pronounced among participants with diabetes aged 20–49 years (n = 20), who also had evidence of poorer diabetes control (eg HbA1c% ≥6.5, 76.6%), relative to participants with diabetes aged 50 years and over (n = 31) (HbA1c% ≥6.5, 32.0%, p =.005). Conclusions: Early and subtle decrements in working memory may be a potential complication of diabetes among Aboriginal and Torres Strait Islander residents of the Torres Strait. Several potentially influential variables were not captured in this study (eg medication and diabetes duration). Greater preventative health resources are required for this population, particularly given the emerging elevated dementia rates linked to chronic disease

Evaluation of the effect of Cooled HaEmodialysis on Cognitive function in patients suffering with end-stage KidnEy Disease (E-CHECKED): feasibility randomised control trial protocol

BACKGROUND: Cognitive impairment is common in haemodialysis (HD) patients and is associated independently with depression and mortality. This association is poorly understood, and no intervention is proven to slow cognitive decline. There is evidence that cooler dialysis fluid (dialysate) may slow white matter changes in the brain, but no study has investigated the effect of cooler dialysate on cognition. This study addresses whether cooler dialysate can prevent the decline in cognition and improve quality of life (QOL) in HD patients. METHODS: This is a multi-site prospective randomised, double-blinded feasibility trial. SETTING: Four HD units in the UK. PARTICIPANTS AND INTERVENTIONS: Ninety HD patients randomised (1:1) to standard care (dialysate temperature 36.5 °C) or intervention (dialysate temperature 35 °C) for 12 months. PRIMARY OUTCOME MEASURE: Change in cognition using the Montreal Cognitive Assessment (MoCA). SECONDARY OUTCOME MEASURES: Recruitment and attrition rates, reasons for non-recruitment, frequency of intradialytic hypotension, depressive symptom scores, patient and carers burden, a detailed computerised cognitive test and QOL assessments. ANALYSIS: mixed method approach, utilising measurement of cognition, questionnaires, physiological measurements and semi-structured interviews. DISCUSSION: The results of this feasibility trial will inform the design of a future adequately powered substantive trial investigating the effect of dialysate cooling on prevention and/or slowing in cognitive decline in patients undergoing haemodialysis using a computerised battery of neuro-cognitive tests. The main hypothesis that would be tested in this future trial is that patients treated with regular conventional haemodialysis will have a lesser decline in cognitive function and a better quality of life over 1 year by using cooler dialysis fluid at 35 °C, versus a standard dialysis fluid temperature of 36.5 °C. This also should reflect in improvements in their abilities for activities of daily living and therefore reduce carers' burden. If successful, the treatment could be universally applied at no extra cost. TRIAL REGISTRATION: ClinicalTrials.gov NCT03645733 . Registered retrospectively on 24 August 2018

Amyloid-Related memory decline in preclinical Alzheimer’s Disease is dependent on APOE ε4 and is detectable over 18-Months

High levels of β-amyloid (Aβ) in the brain and carriage of the APOE ε4 allele have each been linked to cognitive impairment in cognitively normal (CN) older adults. However, the relationship between these two biomarkers and cognitive decline is unclear. The aim of this study was to investigate the relationship between cerebral Aβ level, APOE ε4 carrier status, and cognitive decline over 18 months, in 317 cognitively healthy (CN) older adults (47.6% males, 52.4% females) aged between 60 and 89 years (Mean = 69.9, SD = 6.8). Cognition was assessed using the Cogstate Brief Battery (CBB) and the California Verbal Learning Test, Second Edition (CVLT-II). Planned comparisons indicated that CN older adults with high Aβ who were also APOE ε4 carriers demonstrated the most pronounced decline in learning and working memory. In CN older adults who were APOE ε4 non-carriers, high Aβ was unrelated to cognitive decline in learning and working memory. Carriage of APOE ε4 in CN older adults with low Aβ was associated with a significantly increased rate of decline in learning and unexpectedly, improved cognitive performance on measures of verbal episodic memory over 18 months. These results suggest that Aβ and APOE ε4 interact to increase the rate of cognitive decline in CN older adults and provide further support for the use of Aβ and APOE ε4 as biomarkers of early Alzheimer’s disease