Bayesian estimation of diagnostic accuracy of fecal culture and PCR-based tests for the detection of Salmonella enterica in California cull dairy cattle.

Epidemiological studies of low prevalence disease problems are often hindered by the high cost of diagnostic testing. The objective of this study was to evaluate PCR screening of both individual and pooled fecal samples from culled dairy cows for the invA gene of Salmonella followed by culture to determine if the sensitivity and specificity were comparable to the results from traditional culture methods applied to individual samples. Cows from six different dairies were sampled in all four seasons. A total of 240 individual cow fecal samples, 24 fecal pools and 24 pools of 24-hour tetrathionate enrichment broth were tested. Diagnostic sensitivity of PCR screening followed by culture of PCR positive or indeterminate samples (i.e PCR-CUL method) was lower than that of culture (CUL) when applied to individual fecal samples (94.8%, 99.5%), however the specificity was comparable (99.6% and 97.7% respectively). For pools of five fecal samples and pools of five, 24 h tetrathionate broth samples, the specificity of both tests were comparable (∼98%); however, their sensitivity was only comparable in pooled fecal samples (∼93%) but greater for culture compared to PCR-CUL in pooled broth samples (∼99% versus ∼93%). Compared to culture results from testing of individual fecal samples, testing pooled fecal samples by culture had a relative sensitivity of 74% and relative specificity of 96%, testing pooled fecal samples by PCR-CUL resulted in relative sensitivity of 90% and relative specificity of 96%. Testing of pooled 24-hour enrichment broth by PCR-CUL increased the relative sensitivity and specificity to 100%. PCR testing followed by culture of positive or indeterminate samples is a time saving alternative to traditional methods. In addition, pooling of samples may be a useful method for decreasing cost if study aims can accommodate a moderate loss of relative sensitivity

The prospects of E-Examination Implementation in Nigeria

The massive examination leakages, demand for gratification by teachers, bribe-taking by supervisors and invigilators of examinations have become a global phenomenon. This menace has resulted to general fallen standards of education and Nigeria is no exception, particularly among developing nations. Consequent upon this, all Nigerian universities have resorted to conducting post-entrance “Post-JAMB” examination/screening because of lack of confidence in the conduct of the entrance examinations. This paper proposes a model for e-Examination in Nigeria where all applicants are subjected to online entrance examination as a way of curbing the irregularities as proposed by the Joint Admissions Matriculation Board (JAMB), the body saddled with the responsibility of conducting entrance examinations into all the Nigerian universities. This model was designed and tested in Covenant University, one of the private universities in Nigeria. There were 120 questions drawn from English (30), Mathematics (30), General Science (20), Commercial Courses (20), and Religion Knowledge (20), all for one hour duration. Questionnaires were administered to the applicants at the end of the examination to assess their level of ICT literacy, ease of use of the system and the difficulties encountered. Findings revealed that the system has the potentials to eliminate some of the problems that are associated with the traditional methods of examination such as impersonation and other forms of examination malpractices. The system is easy to use and candidates can get use to it with time. The timing of examination can be spaced without compromising the quality and integrity of the examination. However, much is still desired if the system were to be adopted on a national scale, particularly in terms of infrastructural and manpower development. Similarly, the quest for e-Examination can fast track the development of e-Learning facilities in the country with improved access to education

Do theories of change enable innovation platforms?

Theories of change (ToCs) are increasingly used to articulate pathways for interventions and to support learning. This responds to the recognition of the complexity of agricultural development. Through two examples, this paper examines how ToCs have enabled practitioners to navigate towards impact in settings characterized by a multiplicity of views from different actors on issues of joint concern. The cases discuss how the intervention programs test the ToCs, as well as organize and reflect on feedback. The cases reveal that one cannot predict the route to impact, but one can compose plausible story lines explicating the assumptions. Developing and using ToCs takes time and requires a deliberate effort to monitor actions and changes. Connecting practitioners with researchers makes it possible to use more intermediate theorisations tailored to situated and specific impact pathways. However, the dynamics captured by ToCs may contrast with the donors’ demands for accountability and consistent reliance on a rigid log-frame approach to determine project activities and outputs. Therefore, it is relevant to make explicit choices about how to relate ToCs to M&E efforts

Diversity of lactase persistence in African milk drinkers

The genetic trait of lactase persistence is attributable to allelic variants in an enhancer region upstream of the lactase gene, LCT. To date, five different functional alleles, -13910*T, -13907*G, -13915*G, -14009*G and -14010*C, have been identified. The co-occurrence of several of these alleles in Ethiopian lactose digesters leads to a pattern of sequence diversity characteristic of a 'soft selective sweep'. Here we hypothesise that throughout Africa, where multiple functional alleles co-exist, the enhancer diversity will be greater in groups who are traditional milk drinkers than in non-milk drinkers, as the result of this sort of parallel selection. Samples from 23 distinct groups from 10 different countries were examined. Each group was classified 'Yes 'or 'No' for milk-drinking, and ethnicity, language spoken and geographic location were recorded. Predicted lactase persistence frequency and enhancer diversity were, as hypothesised, higher in the milk drinkers than the non-milk-drinkers, but this was almost entirely accounted for by the Afro-Asiatic language speaking peoples of east Africa. The other groups, including the 'Nilo-Saharan language speaking' milk-drinkers, show lower frequencies of LP and lower diversity, and there was a north-east to south-west decline in overall diversity. Amongst the Afro-Asiatic (Cushitic) language speaking Oromo, however, the geographic cline was not evident and the southern pastoralist Borana showed much higher LP frequency and enhancer diversity than the other groups. Together these results reflect the effects of parallel selection, the stochastic processes of the occurrence and spread of the mutations, and time depth of milk drinking tradition

Contrasting exome constancy and regulatory region variation in the gene encoding CYP3A4: an examination of the extent and potential implications.

OBJECTIVE: CYP3A4 expression varies up to 100-fold among individuals, and, to date, genetic causes remain elusive. As a major drug-metabolizing enzyme, elucidation of such genetic causes would increase the potential for introducing personalized dose adjustment of therapies involving CYP3A4 drug substrates. The foetal CYP3A isoform, CYP3A7, is reported to be expressed in ∼10% of European adults and may thus contribute towards the metabolism of endogenous substances and CYP3A drug substrates. However, little is known about the distribution of the variant expressed in the adult. METHODS: We resequenced the exons, flanking introns, regulatory elements and 3'UTR of CYP3A4 in five Ethiopian populations and incorporated data from the 1000 Genomes Project. Using bioinformatic analysis, we assessed likely consequences of observed CYP3A4 genomic variation. We also conducted the first extensive geographic survey of alleles associated with adult expression of CYP3A7 - that is, CYP3A7*1B and CYP3A7*1C. RESULTS AND CONCLUSION: Ethiopia contained 60 CYP3A4 variants (26 novel) and more variants (>1%) than all non-African populations combined. No nonsynonymous mutation was found in the homozygous form or at more than 2.8% in any population. Seventy-nine per cent of haplotypes contained 3'UTR and/or regulatory region variation with striking pairwise population differentiation, highlighting the potential for interethnic variation in CYP3A4 expression. Conversely, coding region variation showed that significant interethnic variation is unlikely at the protein level. CYP3A7*1C was found at up to 17.5% in North African populations and in significant linkage disequilibrium with CYP3A5*3, indicating that adult expression of the foetal isoform is likely to be accompanied by reduced or null expression of CYP3A5

Perceived Correctional Officers' Power Sources and Compliance among Correctional Facility Inmates in Osun State, Nigeria

The continued crisis in correctional facilities which has led to jail breaks and avoidable deaths has been a serious problem for correctional officers and governments. Understanding the application of power sources which could have been used in gaining compliance in these facilities have been ignored by researchers in Nigeria and Africa in general. Therefore, the present study was out to investigate the influence of perceived power sources and compliance among correctional facilities inmates. 150 inmates selected from two correctional facilities in Ilesa and Ile-Ife, Osun State were used in the study.  A questionnaire measuring their demographic data and perceived power sources and compliance was used for data collection. The results of the study indicated that correctional officers’ power sources (expert, rewards, legitimate, coercive, and referent) significantly jointly influenced inmates compliance to rules and assigned duties (F (5,149), = 12.026, P < .05). Also no significant difference existed between male and female inmates’ compliance based on perceived correctional officers power sources (t= (148); = -.483, P>.05). While years of incarceration of inmates significantly influenced inmates level of compliance based on perceived correctional officer’s power sources (F (4, 149) = 1.183, P<.05). The study recommended that, the managements of correctional facilities should train their officers to acquire skills that would enable them handle inmates, promote and  assigned officers legally to positions of authority and also make available certain rewards into the officers in order to provide same to inmates who comply to rules, assigned duties and responsibilities. Keywords: Power Sources, Compliance, Perception, Correctional, Duties, Responsibilities, Inmate