ATCA monitoring of gamma-ray loud AGN

As a critical part of the Tracking Active Galactic Nuclei with Austral Milliarcsecond Interferometry (TANAMI) program, in November 2007 the Australia Telescope Compact Array (ATCA) started monitoring the radio spectra of a sample of southern hemisphere active galactic nuclei (AGN) that were selected as likely candidates for detection (as well as a control sample) by the Large Area Telescope (LAT) aboard the Fermi Gamma Ray Space Observatory. The initial sample was chosen based on properties determined from AGN detections by the Energetic Gamma Ray Experiment Telescope (EGRET). Most of the initial sample has been detected by Fermi/LAT and with the addition of new detections the sample has grown to include 226 AGN, 133 of which have data for more than one epoch. For the majority of these AGN, our monitoring program provides the only dynamic radio spectra available. The ATCA receiver suite makes it possible to observe several sources at frequencies between 4.5 and 41 GHz in a few hours, resulting in an excellent measure of spectral index at each epoch. By examining how the spectral index changes over time, we aim to investigate the mechanics of radio and gamma-ray emission from AGN jets.Comment: 5 pages, 1 figure, 2012 Fermi & Jansky Proceedings - eConf C111110

'Kids sold, desperate moms need cash': Media representations of Zimbabwean women migrants

The article draws on 575 randomly selected articles from the South African Media database to explore the representation of Zimbabwean women migrants. Using critical discourse analysis (CDA), the article shows that some of the dominant construction types depict a picture of caricatured, stereotypical and stigmatised Zimbabwean migrant women without voice and individuality. In turn, the diversity of their actualities is not captured in the process of constructing the twin images of Zimbabwean women as victims and as purveyors of decadent and other negative social ills in society. We conclude that Zimbabwean women migrants appear in the SA media primarily in three negative images: suppliers of sexual services, as un-motherly, and as victims. We also conclude that there is need for media to capture the voices of migrant women recounting their everyday lived experiences in different political and socio-economic contexts in order to account for the migrant women's voices of resilience, defiance and victimhood and of agency, against the normalising and marginalising influences of political institutions and national border controls. This would also help capture the transformative nature of migration to the women, the 'home' in Zimbabwe and the 'home' in South Africa.IS

Characterisation of Long Baseline Calibrators at 2.3 GHz

We present a detailed multi-epoch analysis of 31 potential southern hemisphere radio calibrators that were originally observed as part of a program to maintain the International Celestial Reference Frame (ICRF). At radio wavelengths, the primary calibrators are Active Galactic Nuclei (AGN), powerful radio emitters which exist at the centre of most galaxies. These are known to vary at all wavelengths at which they have been observed. By determining the amount of radio source structure and variability of these AGN, we determine their suitability as phase calibrators for long baseline radio interferometry at 2.3 GHz. For this purpose, we have used a set of complementary metrics to classify these 31 southern sources into five categories pertaining to their suitability as VLBI calibrators. We find that all of the sources in our sample would be good interferometric calibrators and almost ninety per cent would be very good calibrators.Comment: 9 pages, 7 Figures, accepted MNRA

Prognostic model to predict postoperative acute kidney injury in patients undergoing major gastrointestinal surgery based on a national prospective observational cohort study.

Background: Acute illness, existing co-morbidities and surgical stress response can all contribute to postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery. The aim of this study was prospectively to develop a pragmatic prognostic model to stratify patients according to risk of developing AKI after major gastrointestinal surgery. Methods: This prospective multicentre cohort study included consecutive adults undergoing elective or emergency gastrointestinal resection, liver resection or stoma reversal in 2-week blocks over a continuous 3-month period. The primary outcome was the rate of AKI within 7 days of surgery. Bootstrap stability was used to select clinically plausible risk factors into the model. Internal model validation was carried out by bootstrap validation. Results: A total of 4544 patients were included across 173 centres in the UK and Ireland. The overall rate of AKI was 14·2 per cent (646 of 4544) and the 30-day mortality rate was 1·8 per cent (84 of 4544). Stage 1 AKI was significantly associated with 30-day mortality (unadjusted odds ratio 7·61, 95 per cent c.i. 4·49 to 12·90; P < 0·001), with increasing odds of death with each AKI stage. Six variables were selected for inclusion in the prognostic model: age, sex, ASA grade, preoperative estimated glomerular filtration rate, planned open surgery and preoperative use of either an angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker. Internal validation demonstrated good model discrimination (c-statistic 0·65). Discussion: Following major gastrointestinal surgery, AKI occurred in one in seven patients. This preoperative prognostic model identified patients at high risk of postoperative AKI. Validation in an independent data set is required to ensure generalizability

Effects of fluoxetine on functional outcomes after acute stroke (FOCUS): a pragmatic, double-blind, randomised, controlled trial

Background Results of small trials indicate that fluoxetine might improve functional outcomes after stroke. The FOCUS trial aimed to provide a precise estimate of these effects. Methods FOCUS was a pragmatic, multicentre, parallel group, double-blind, randomised, placebo-controlled trial done at 103 hospitals in the UK. Patients were eligible if they were aged 18 years or older, had a clinical stroke diagnosis, were enrolled and randomly assigned between 2 days and 15 days after onset, and had focal neurological deficits. Patients were randomly allocated fluoxetine 20 mg or matching placebo orally once daily for 6 months via a web-based system by use of a minimisation algorithm. The primary outcome was functional status, measured with the modified Rankin Scale (mRS), at 6 months. Patients, carers, health-care staff, and the trial team were masked to treatment allocation. Functional status was assessed at 6 months and 12 months after randomisation. Patients were analysed according to their treatment allocation. This trial is registered with the ISRCTN registry, number ISRCTN83290762. Findings Between Sept 10, 2012, and March 31, 2017, 3127 patients were recruited. 1564 patients were allocated fluoxetine and 1563 allocated placebo. mRS data at 6 months were available for 1553 (99·3%) patients in each treatment group. The distribution across mRS categories at 6 months was similar in the fluoxetine and placebo groups (common odds ratio adjusted for minimisation variables 0·951 [95% CI 0·839–1·079]; p=0·439). Patients allocated fluoxetine were less likely than those allocated placebo to develop new depression by 6 months (210 [13·43%] patients vs 269 [17·21%]; difference 3·78% [95% CI 1·26–6·30]; p=0·0033), but they had more bone fractures (45 [2·88%] vs 23 [1·47%]; difference 1·41% [95% CI 0·38–2·43]; p=0·0070). There were no significant differences in any other event at 6 or 12 months. Interpretation Fluoxetine 20 mg given daily for 6 months after acute stroke does not seem to improve functional outcomes. Although the treatment reduced the occurrence of depression, it increased the frequency of bone fractures. These results do not support the routine use of fluoxetine either for the prevention of post-stroke depression or to promote recovery of function. Funding UK Stroke Association and NIHR Health Technology Assessment Programme

Independent and combined effects of improved water, sanitation, and hygiene, and improved complementary feeding, on child stunting and anaemia in rural Zimbabwe: a cluster-randomised trial.

BACKGROUND: Child stunting reduces survival and impairs neurodevelopment. We tested the independent and combined effects of improved water, sanitation, and hygiene (WASH), and improved infant and young child feeding (IYCF) on stunting and anaemia in in Zimbabwe. METHODS: We did a cluster-randomised, community-based, 2 × 2 factorial trial in two rural districts in Zimbabwe. Clusters were defined as the catchment area of between one and four village health workers employed by the Zimbabwe Ministry of Health and Child Care. Women were eligible for inclusion if they permanently lived in clusters and were confirmed pregnant. Clusters were randomly assigned (1:1:1:1) to standard of care (52 clusters), IYCF (20 g of a small-quantity lipid-based nutrient supplement per day from age 6 to 18 months plus complementary feeding counselling; 53 clusters), WASH (construction of a ventilated improved pit latrine, provision of two handwashing stations, liquid soap, chlorine, and play space plus hygiene counselling; 53 clusters), or IYCF plus WASH (53 clusters). A constrained randomisation technique was used to achieve balance across the groups for 14 variables related to geography, demography, water access, and community-level sanitation coverage. Masking of participants and fieldworkers was not possible. The primary outcomes were infant length-for-age Z score and haemoglobin concentrations at 18 months of age among children born to mothers who were HIV negative during pregnancy. These outcomes were analysed in the intention-to-treat population. We estimated the effects of the interventions by comparing the two IYCF groups with the two non-IYCF groups and the two WASH groups with the two non-WASH groups, except for outcomes that had an important statistical interaction between the interventions. This trial is registered with ClinicalTrials.gov, number NCT01824940. FINDINGS: Between Nov 22, 2012, and March 27, 2015, 5280 pregnant women were enrolled from 211 clusters. 3686 children born to HIV-negative mothers were assessed at age 18 months (884 in the standard of care group from 52 clusters, 893 in the IYCF group from 53 clusters, 918 in the WASH group from 53 clusters, and 991 in the IYCF plus WASH group from 51 clusters). In the IYCF intervention groups, the mean length-for-age Z score was 0·16 (95% CI 0·08-0·23) higher and the mean haemoglobin concentration was 2·03 g/L (1·28-2·79) higher than those in the non-IYCF intervention groups. The IYCF intervention reduced the number of stunted children from 620 (35%) of 1792 to 514 (27%) of 1879, and the number of children with anaemia from 245 (13·9%) of 1759 to 193 (10·5%) of 1845. The WASH intervention had no effect on either primary outcome. Neither intervention reduced the prevalence of diarrhoea at 12 or 18 months. No trial-related serious adverse events, and only three trial-related adverse events, were reported. INTERPRETATION: Household-level elementary WASH interventions implemented in rural areas in low-income countries are unlikely to reduce stunting or anaemia and might not reduce diarrhoea. Implementation of these WASH interventions in combination with IYCF interventions is unlikely to reduce stunting or anaemia more than implementation of IYCF alone. FUNDING: Bill & Melinda Gates Foundation, UK Department for International Development, Wellcome Trust, Swiss Development Cooperation, UNICEF, and US National Institutes of Health.The SHINE trial is funded by the Bill & Melinda Gates Foundation (OPP1021542 and OPP113707); UK Department for International Development; Wellcome Trust, UK (093768/Z/10/Z, 108065/Z/15/Z and 203905/Z/16/Z); Swiss Agency for Development and Cooperation; US National Institutes of Health (2R01HD060338-06); and UNICEF (PCA-2017-0002)

Scenario-Based Digital Forensic Investigation of Compromised MySQL Database

Insider and outsider database threats have more often than not posed a greater challenge as far as integrity and investigation of databases is concerned. Database forensic investigation is a process through which scientifically proven methods can be used to create a hypothesis that can prove or disprove the occurrence of a potential security incident. This paper explores the techniques that can be used to conduct forensic investigations of a compromised MySQL database. The authors have simulated investigative scenarios that have aided to conduct forensic investigative processes and the results are promising

The socio-ecological impacts of small dams: A case study of Mushandike Sanctuary, Zimbabwe

Demand and supply of water over space and time is being influenced by changes in land use, population growth, industrial development and construction of dams. In this study, we focus on Mushandike dam located in Mushandike Sanctuary, Zimbabwe, and evaluate the socio-ecological impacts associated with this dam. We gathered data through interviews with local farmers and agricultural extension officers. We also retrieved historical data on rainfall, water levels, fish harvest and irrigated agricultural production linked to Mushandike dam. Following Mushandike dam construction, several people were relocated and a resettlement scheme adjacent to Mushandike Sanctuary was established with water from the dam being used for irrigation. The relocation had positive impacts in the early years of the irrigated agricultural schemes as the standard of living for the families improved. However, the situation has recently changed as the farmers are now faced with water scarcity for crop irrigation. The irrigation scheme has failed to operate for over a year now due to competing demands on the water resource. This study attributes the main cause for the water level decline in Mushandike dam to the increasing losses of water as it flows from the dam and to the irrigation canals. Water scarcity has resulted in the reduction in crop production and decreased aquatic life in the dam. There is need therefore, to improve water management in Mushandike catchment to allow for sustainable conservation and development