Mimicking human neuronal pathways in silico: an emergent model on the effective connectivity

International audienceWe present a novel computational model that detects temporal configurations of a given human neuronal pathway and constructs its artificial replication. This poses a great challenge since direct recordings from individual neurons are impossible in the human central nervous system and therefore the underlying neuronal pathway has to be considered as a black box. For tackling this challenge, we used a branch of complex systems modeling called artificial self-organization in which large sets of software entities interacting locally give rise to bottom-up collective behaviors. The result is an emergent model where each software entity represents an integrate-and-fire neuron. We then applied the model to the reflex responses of single motor units obtained from conscious human subjects. Experimental results show that the model recovers functionality of real human neuronal pathways by comparing it to appropriate surrogate data. What makes the model promising is the fact that, to the best of our knowledge, it is the first realistic model to self-wire an artificial neuronal network by efficiently combining neuroscience with artificial self-organization. Although there is no evidence yet of the model's connectivity mapping onto the human connectivity, we anticipate this model will help neuroscientists to learn much more about human neuronal networks, and could also be used for predicting hypotheses to lead future experiments

Redefining political–administrative relationships in South Africa

This article is an overview of shifting political–administrative relationships in South Africa, with particular reference to growing politicization (partisan control of the bureaucracy). Studies of politicization of public services are important because political involvement in management has often led to negative effects on service delivery. The article sets out a theoretical framework for political–administrative relationships, examining the growing politicization of public services, the impact of New Public Management (NPM) and political–administrative relationships in developing countries. It then looks at political–administrative relationships in South Africa, including the apartheid history, the development of a new framework in the democratic South Africa and politicization in the staffing of the public service. It examines three functional areas – the decentralization of powers, contract appointments and performance man- agement – and discusses the implications of this changing framework for service delivery. The methodology consisted of interviews with a number of senior government officials, including three current directors-general and a former Minister for the Public Service and Administration, an analysis of government legislation, Public Service Commission (PSC) data including surveys, unpublished data of the Department of Public Service and Administration (DPSA), policy papers of the African National Congress (ANC) and an Organisation for Economic Co-operation and Development (OECD) study of political involvement in bureaucracies. The article concludes that growing politicization of the public service has contributed to poor service delivery, and that the South African government needs to place greater emphasis on merit as the basis for appointments and promotions

Evidence-Based Medicine and the Practicing Clinician

OBJECTIVE: To assess the attitudes of practicing general internists toward evidence-based medicine (EBM—defined as the process of systematically finding, appraising, and using contemporaneous research findings as the basis for clinical decisions) and their perceived barriers to its use. DESIGN: Cross-sectional, self-administered mail questionnaire conducted between June and October 1997. SETTING: Canada. PARTICIPANTS: Questionnaires were sent to all 521 physician members of the Canadian Society of Internal Medicine with Canadian mailing addresses; 296 (60%) of 495 eligible physicians responded. Exclusion of two incomplete surveys resulted in a final sample size of 294. MAIN RESULTS: Mean age of respondents was 46 years, 80% were male, and 52% worked in large urban medical centers. Participants reported using EBM in their clinical practice always (33, 11%), often (173, 59%), sometimes (80, 27%), or rarely/never (8, 3%). There were no significant differences in demographics, training, or practice types or locales on univariate or multivariate analyses between those who reported using EBM often or always and those who did not. Both groups reported high usage of traditional (non-EBM) information sources: clinical experience (93%), review articles (73%), the opinion of colleagues (61%), and textbooks (45%). Only a minority used EBM-related information sources such as primary research studies (45%), clinical practice guidelines (27%), or Cochrane Collaboration Reviews (5%) on a regular basis. Barriers to the use of EBM cited by respondents included lack of relevant evidence (26%), newness of the concept (25%), impracticality for use in day-to-day practice (14%), and negative impact on traditional medical skills and “the art of medicine” (11%). Less than half of respondents were confident in basic skills of EBM such as conducting a literature search (46%) or evaluating the methodology of published studies (34%). However, respondents demonstrated a high level of interest in further education about these tasks. CONCLUSIONS: The likelihood that physicians will incorporate EBM into their practice cannot be predicted by any demographic or practice-related factors. Even those physicians who are most enthusiastic about EBM rely more on traditional information sources than EBM-related sources. The most important barriers to increased use of EBM by practicing clinicians appear to be lack of knowledge and familiarity with the basic skills, rather than skepticism about the concept

Impacto da saúde bucal no cotidiano de idosos institucionalizados e não institucionalizados da cidade do Recife (PE, Brasil) Impact of oral health in the daily life of institutionalized and non institutionalized elder in the city of Recife (PE, Brazil)

Este artigo tem como objetivo avaliar a influência da saúde bucal no cotidiano de idosos institucionalizados e não institucionalizados da cidade do Recife (PE), bem como verificar se a saúde bucal tem a mesma relevância para os dois grupos estudados. Para avaliar a percepção de saúde bucal, utilizou-se o índice Geriatric Oral Health Assessment Index (GOHAI). As faixas do GOHAI foram categorizadas em baixa percepção (<= 50), média ou regular (51 a 60) e alta (57 a 60). As condições de saúde bucal foram representadas pelo índice CPO-D (dentes cariados, perdidos e obturados). Observou-se que o percentual dos que tinham o GOHAI até 50 pontos (baixa percepção de saúde bucal) foi bem elevado no grupo dos não institucionalizados em relação ao grupo dos institucionalizados (92,2% x 64,9%). As médias do CPO-D e do número de dentes perdidos foram correspondentemente mais elevadas no grupo de institucionalizados do que no grupo de não institucionalizados (96,01% x 87,87%). Conclusões: a percepção de saúde bucal foi baixa para mais da metade dos idosos examinados, existindo diferença significante entre os dois grupos em relação à categoria do GOHAI, sendo os valores mais baixos encontrados para o grupo não institucionalizado. O resultado da percepção de saúde foi compatível com o grande número de dentes cariados e perdidos.<br>The objective of the study is to assess the influence of oral health in the daily routine of both institutionalized and non-institutionalized elders living in the city of Recife-PE, as well as to come to conclusions concerning the relevance level of oral health in both groups. In order to assess the perception of oral health, it was used the Geriatric Oral Health Assessment Index (GOHAI). The GOHAI levels, concerning the perception, were categorized in: low (<= 50), average (51 to 60) and high (57 to 60). Oral health conditions were represented by the DMFT index (with cavity, lost and repaired teeth). It was observed that the percentage of elderly with a GOHAI not higher than 50 (low perception of oral health) was rather higher in the non-institutionalized group than in the institutionalized (92,2% x 64,9%). The average DMFT and the number of lost teeth were higher in the institutionalized group (96,01% x 87,87%). The perception of oral health was lower for more than half of the examined elderly population, but there being a meaningful difference between the two groups concerning the GOHAI, with lower levels for the non-institutionalized group. The result of the perception of oral health was compatible with the high number of decayed and lost teeth

Maternal anemia is a potential risk factor for anemia in children aged 6–59 months in Southern Africa: a multilevel analysis

Abstract Background The effect of maternal anemia on childhood hemoglobin status has received little attention. Thus, we examined the potential association between maternal anemia and childhood anemia (aged 6–59 months) from selected Southern Africa countries. Methods A cross-sectional study using nationally representative samples of children aged 6–59 months from the 2010 Malawi, 2011 Mozambique, 2013 Namibia, and 2010–11 Zimbabwe demographic and health surveys (DHS) was conducted. Generalized linear mixed models (GLMMs) were constructed to test the associations between maternal anemia and childhood anemia, controlling for individual and community sociodemographic covariates. Results The GLMMs showed that anemic mothers had increased odds of having an anemic child in all four countries; adjusted odds ratio (aOR = 1.69 and 95% confidence interval [CI]:1.37–2.13) in Malawi, (aOR = 1.71; 95% CI: 1.37–2.13) in Mozambique, (aOR = 1.55; 95% CI: 1.08–2.22) in Namibia, and (aOR = 1.52; 95% CI: 1.25–1.84) in Zimbabwe. Furthermore, the odds of having an anemic child was higher in communities with a low percentage of anemic mothers (aOR = 1.52; 95% CI: 1.19–1.94) in Mozambique. Conclusions Despite the long-standing efforts to combat childhood anemia, the burden of this condition is still rampant and remains a significant problem in Southern Africa. Thus, public health strategies aimed at reducing childhood anemia should focus more on addressing infections, and micronutrient deficiencies both at individual and community levels in Southern Africa