Mathematical Properties of a Class of Four-dimensional Neutral Signature Metrics

While the Lorenzian and Riemanian metrics for which all polynomial scalar curvature invariants vanish (the VSI property) are well-studied, less is known about the four-dimensional neutral signature metrics with the VSI property. Recently it was shown that the neutral signature metrics belong to two distinct subclasses: the Walker and Kundt metrics. In this paper we have chosen an example from each of the two subcases of the Ricci-flat VSI Walker metrics respectively. To investigate the difference between the metrics we determine the existence of a null, geodesic, expansion-free, shear-free and vorticity-free vector, and classify these spaces using their infinitesimal holonomy algebras. The geometric implications of the holonomy algebras are further studied by identifying the recurrent or covariantly constant null vectors, whose existence is required by the holonomy structure in each example. We conclude the paper with a simple example of the equivalence algorithm for these pseudo-Riemannian manifolds, which is the only approach to classification that provides all necessary information to determine equivalence.Comment: 18 page

Skills acquired and passed on: the collaboration between the University of Bergen and Makerere University libraries and their new partners in the north and south

Makerere University in Uganda and the University of Bergen in Norway celebrate ten years of collaboration in 2009. The collaboration includes the libraries in the two Universities, focusing on continuing professional development. This paper reports the activities of the collaboration between the two University libraries, and highlights the multiplier effect of the collaboration, which has led to new partners at the University of Juba in Southern Sudan, the East African School of Library and Information Science (EASLIS) at Makerere and the Norwegian School of Librarianship at Oslo University College. The new partners have joined to implement the Juba University Library Automation Project (JULAP) that is funded by the Norwegian Ministry of Foreign Affairs. JULAP aims to rebuild the Juba University Library that was closed because of the war in 1985. The project has two main components: automation of the library and training of library staff who are already working in the library, as well as sponsoring young people for a Bachelor’s degree in Librarianship at EASLIS. The training of library staff has a theoretical component conducted by EASLIS, while the practical component is handled by Makerere University Library staff using the skills they acquired over time from collaborations with skilled librarians from the North. Part of the project includes the acquisition of a library system, and the training of staff to use the system. The paper then outlines the activities of the project, the challenges faced and how they have been addressed, the achievements and future plans. Although most collaboration usually involves two institutions, this paper highlights the growth of the collaboration from two institutions to where it is now, and the audience is encouraged to learn from this experience and replicate it to be able to ‘build bridges’ of LIS education in Developing countries

Reducing child undernutrition through dietary diversification, reduced aflatoxin exposure, and improved hygiene practices: the immediate impacts in central Tanzania

Open Access Article; Published online: 28 Nov 2019The study aimed to quantify the immediate effects of dietary diversification, food safety, and hygiene interventions on child undernutrition in four rural villages in Kongwa district of central Tanzania. One hundred mothers with their children of less than 24 months old were recruited for this study. The difference-in-difference (DID) method was used to assess the effects of intensive intervention through a learning-by-doing process on the topic of aflatoxin free diversified food utilization and improved hygiene practices. Periodic anthropometric measurements were conducted on the 0th, 7th, 14th, and 21st days, and DID estimator showed the significant and positive average marginal effects of the intervention on Z-Scores being 0.459, 0.252, and 0.493 for wasting, stunting, and underweight, respectively. Notably, at the end of the study, the mean aflatoxin M1 level in urine samples decreased by 64% in the intervention group, while it decreased by 11% in the control group. The study provides quantitative evidence on intensive 21-day training for mothers incorporating integrated technologies yielded positive impacts on their children’s nutritional outcomes

Growth, immune and viral responses in HIV infected African children receiving highly active antiretroviral therapy: a prospective cohort study.

BACKGROUND: Scale up of paediatric antiretroviral therapy in resource limited settings continues despite limited access to routine laboratory monitoring. We documented the weight and height responses in HIV infected Ugandan children on highly active antiretroviral therapy and determined clinical factors associated with successful treatment outcomes. METHODS: A prospective cohort of HIV infected children were initiated on HAART and followed for 48 weeks. Body mass index for age z scores(BAZ), weight and height-for-age z scores (WAZ & HAZ) were calculated: CD4 cell % and HIV-1 RNA were measured at baseline and every 12 weeks. Treatment outcomes were classified according to; both virological and immunological success (VS/IS), virological failure and immunological success (VF/IS). virological success and immunological failure (VS/IF) and both virological and immunological failure (VF/IF). RESULTS: From March 2004 until May 2006, 124 HIV infected children were initiated on HAART. The median age (IQR) was 5.0 years (2.1 - 7.0) and 49% (61/124) were female. The median [95% confidence interval (CI)] BAZ, WAZ and HAZ at baseline were 0.29 (-2.9, -1.2), -1.2 (-2.1, -0.5) and -2.06 (-2.9, -1.2) respectively. Baseline median CD4 cell % and log10 HIV-1 RNA were; 11.8% (7.5-18.0) and 5.6 (5.2-5.8) copies/ml. By 48 weeks, mean WAZ and HAZ in the VF/IS group, which was younger, increased from - 0.98 (SD 1.7) to + 1.22 (SD 1.2) and from -1.99 (1.7) to + 0.76 (2.4) respectively. Mean increase in WAZ and HAZ in the VS/IF group, an older group was modest, from -1.84 (1.3) to - 0.41 (1.2) and -2.25 (1.2) to -1.16 (1.3) respectively. Baseline CD4 cell % [OR 6.97 95% CI (2.6 -18.6)], age [OR 4.6 95% CI (1.14 -19.1)] and WHO clinical stage [OR 3.5 95%CI (1.05 -12.7)] were associated with successful treatment outcome. CONCLUSIONS: HIV infected Ugandan children demonstrated a robust increase in height and weight z scores during the first 48 weeks of HAART, including those who failed to completely suppress virus. Older children initiating HAART with severe immune suppression were less likely to achieve a successful treatment outcome. These data emphasize the importance of initiating HAART early to ensure adequate immune and growth responses

Reducing Child Undernutrition through Dietary Diversification, Reduced Aflatoxin Exposure, and Improved Hygiene Practices: The Immediate Impacts in Central Tanzania

The study aimed to quantify the immediate effects of dietary diversification, food safety, and hygiene interventions on child undernutrition in four rural villages in Kongwa district of central Tanzania. One hundred mothers with their children of less than 24 months old were recruited for this study. The difference-in-difference (DID) method was used to assess the effects of intensive intervention through a learning-by-doing process on the topic of aflatoxin free diversified food utilization and improved hygiene practices. Periodic anthropometric measurements were conducted on the 0th, 7th, 14th, and 21st days, and DID estimator showed the significant and positive average marginal effects of the intervention on Z-Scores being 0.459, 0.252, and 0.493 for wasting, stunting, and underweight, respectively. Notably, at the end of the study, the mean aflatoxin M1 level in urine samples decreased by 64% in the intervention group, while it decreased by 11% in the control group. The study provides quantitative evidence on intensive 21-day training for mothers incorporating integrated technologies yielded positive impacts on their children’s nutritional outcomes

Sociocultural factors influencing breastfeeding practices in two slums in Nairobi, Kenya

Background: Despite numerous interventions promoting optimal breastfeeding practices in Kenya, pockets of suboptimal breastfeeding practices are documented in Kenya’s urban slums. This paper describes cultural and social beliefs and practices that influence breastfeeding in two urban slums in Nairobi, Kenya. Methods: Qualitative data were collected in Korogocho and Viwandani slums through 10 focus group discussions and 19 in-depth interviews with pregnant, breastfeeding women and community health volunteers and 11 key-informant interviews with community leaders. Interviews were audiotaped, transcribed verbatim, coded in NVIVO and analyzed thematically. Results: Social and cultural beliefs and practices that result to suboptimal breastfeeding practices were highlighted including; considering colostrum as ‘dirty’ or ‘curdled milk’, a curse ‘bad omen’ associated with breastfeeding while engaging in extra marital affairs, a fear of the ‘evil eye’ (malevolent glare which is believed to be a curse associated with witchcraft) when breastfeeding in public and breastfeeding being associated with sagging breasts. Positive social and cultural beliefs were also identified including the association of breast milk with intellectual development and good child health. The beliefs and practices were learnt mainly from spouses, close relatives and peers. Conclusion: Interventions promoting behavior change with regards to breastfeeding should focus on dispelling the beliefs and practices that result to suboptimal breastfeeding practices and to build on the positive ones, while involving spouses and other family members as they are important sources of information on breastfeeding

Perinatal risk factors for neonatal encephalopathy: an unmatched case-control study

OBJECTIVE: Neonatal encephalopathy (NE) is the third leading cause of child mortality. Preclinical studies suggest infection and inflammation can sensitise or precondition the newborn brain to injury. This study examined perinatal risks factor for NE in Uganda. DESIGN: Unmatched case-control study. SETTING: Mulago National Referral Hospital, Kampala, Uganda. METHODS: 210 term infants with NE and 409 unaffected term infants as controls were recruited over 13 months. Data were collected on preconception, antepartum and intrapartum exposures. Blood culture, species-specific bacterial real-time PCR, C reactive protein and placental histology for chorioamnionitis and funisitis identified maternal and early newborn infection and inflammation. Multivariable logistic regression examined associations with NE. RESULTS: Neonatal bacteraemia (adjusted OR (aOR) 8.67 (95% CI 1.51 to 49.74), n=315) and histological funisitis (aOR 11.80 (95% CI 2.19 to 63.45), n=162) but not chorioamnionitis (aOR 3.20 (95% CI 0.66 to 15.52), n=162) were independent risk factors for NE. Among encephalopathic infants, neonatal case fatality was not significantly higher when exposed to early neonatal bacteraemia (OR 1.65 (95% CI 0.62 to 4.39), n=208). Intrapartum antibiotic use did not improve neonatal survival (p=0.826). After regression analysis, other identified perinatal risk factors (n=619) included hypertension in pregnancy (aOR 3.77), male infant (aOR 2.51), non-cephalic presentation (aOR 5.74), lack of fetal monitoring (aOR 2.75), augmentation (aOR 2.23), obstructed labour (aOR 3.8) and an acute intrapartum event (aOR 8.74). CONCLUSIONS: Perinatal infection and inflammation are independent risk factors for NE in this low-resource setting, supporting a role in the aetiological pathway of term brain injury. Intrapartum antibiotic administration did not mitigate against adverse outcomes. The importance of intrapartum risk factors in this sub-Saharan African setting is highlighted