Primary beam effects of radio astronomy antennas -- II. Modelling the MeerKAT L-band beam

After a decade of design and construction, South Africa's SKA-MID precursor MeerKAT has begun its science operations. To make full use of the widefield capability of the array, it is imperative that we have an accurate model of the primary beam of its antennas. We have taken available L-band full-polarization 'astro-holographic' observations of three antennas and a generic electromagnetic simulation and created sparse representations of the beams using principal components and Zernike polynomials. The spectral behaviour of the spatial coefficients has been modelled using discrete cosine transform. We have provided the Zernike-based model over a diameter of 10 deg averaged over the beams of three antennas in an associated software tool (EIDOS) that can be useful in direction-dependent calibration and imaging. The model is more accurate for the diagonal elements of the beam Jones matrix and at lower frequencies. As we get more accurate beam measurements and simulations in the future, especially for the cross-polarization patterns, our pipeline can be used to create more accurate sparse representations of MeerKAT beams.Comment: 16 pages, 18 figures. This is a pre-copyedited, author-produced PDF of an article accepted for publication in MNRAS following peer review. The version of record [K. M. B. Asad et al., 2021] is available online at: https://doi.org/10.1093/mnras/stab10

Scaling up of CSA Platforms at the Subnational (District) Levels in Ghana: a Progressive Achievement of Theghana CCAFS Science-Policy Platform

Globally the picture on climate change and its effects on humanity appear quite disturbing as food systems and consumption patterns are sliding towards low against prediction values. In Ghana population expansion as a driver has quadrupled now and calls for more food and fibre needs than ten decades ago (Karbo et al, 2015). The awareness of climate change on socio-economic development among development workers, scientists and policy decision makers appears high though more attention has been given to the search for biophysical solutions than the policy institutional environment enabling their uptake. The CCAFS programme in West Africa coordinated by ICRISAT, Bamako involving Ghana, Mali and Senegal was able to set up national multi-stakeholder platforms for sharing information on climate change and related policy issues. The platforms also provide a linkage mechanism between research, policy decision makers and community level actors in order to positively influence climate change investments and project trajectory in agriculture with effective adaptive, resilient and mitigation outcomes at the farmer level. The Ghana CCAFS Science –Policy Platform formation preceded with a meeting held in Burkina Faso in 2013 where a three member team from Ghana was involved with subsequent drafting and submission of proposal in request for funding leading to its establishment. The Ghana national climate change science policy platform as a multi-stakeholder institutional innovation came into being in 2013 with the support of CCAFS West Africa, set out to bridge science-policy literacy gap at the national and sub-national levels. In 2014, Ghana through the collaborative efforts of the national Platform implemented CCAFS Flagship4 activities which sought to deepen interaction at all levels. This culminated into the establishment of platforms at Lawra, Jirapa and Nandom districts with the view to strengthen climate change discourse, attitudinal change and actions at that level while maintaining a vibrant functional linkage mechanism with the national platforms for policy influence. An assessment of climate change policy and institutional context by Essegbey 2014, in these three districts, revealed that large gap exists between the national and subnational levels in terms of policy development and dissemination. The report identified weaknesses in harnessing societal grassroots inputs for policy formulation process and lack of awareness and knowledge about the policy especially in the decentralized levels of society in these three districts (Essegbey 2014). This suggests that policy literacy is very low and could pose challenge to effective implementation of the NCCP. The establishment of these platforms were necessary to help bridge the policy literacy gap. Today, these platforms provide soft landing for research activities and projects such ASSAR project, Water and Land Ecosystem project etc. The platforms also provide inputs into the districts level development annual plans. Effective networking with other local and international bodies have also been recognised. This info note seeks to give a process description of the scaling up of district sciencepolicy platforms in Ghana, the structures, the perceptions of the actors with particular reference to the platform, perceived functions, fears and organizational leadership diversities

Climate-Smart Agricultural Practices in Ghana

The contribution of the agricultural sector to Ghana's economy has been dwindling in relative terms from a high of 39 per cent in 1990s to about 21 per cent in 2014 (ISSER, 2015). This reduction to the sector’s GDP notwithstanding, sector continues to play a major role in the country’s socio-economic growth. However, the sector is threatened by the effects of climate variability and climate change. There are already efforts being made at various levels to address this threat through the adoption and adaption of various technologies and practices. This paper profiles technologies and practices that respond to CSA principles and characteristics in the northern Guinea savannah and Forest agro-ecological zones of Ghana. Two regional workshops were held in Wa and Kumasi for the savannah and forest zones respectively. Over 200 participants consisting of farmers, NGOs, FBOs, MoFA directors and extension workers, traditional rulers, District Chief Executives, Academia and researchers were involved in the technology identification and profiling employing a matrix-ranking tool in the working groups at the various workshops. Participants identified 61 and 21 CSA technologies and practices in the Guinea Savannah and the Forest zones respectively and recommended scaling up of these technologies in the various zones. While the traditional rulers and farmers bemoaned the lack of synergy among the institutions involved in CSA and the lack of policy continuity, policy makers called for strengthening of collaboration between the stakeholders for CSA. The policy and decision makers further called on scientists to make CSA accessible at the farmer level through demonstrations and fact sheets for awareness creation and education and promised to support research and extension with the needed funds. Representatives of Academia and Research on their part pledged solutions that are sustainable and have climate change adaptation and mitigation effects for profit and the well-being of farmers

Systems and Operations of the Ghana Science-Policy Dialogue Platform on Climate Change, Agriculture and Food Security

The threat posed by climate change and its variability within sub-Saharan Africa especially West Africa is compounded by its weak economies and high dependence on Agriculture as a major driver of economic growth. Ghana has since 2010 undertaken several initiatives towards development of comprehensive programmes (strategies) to enhance national adaptation to climate change. Diverse governmental and academic/research institutions, private sector and individuals have initiated programmes and projects aimed at delivering on CSA to enhance livelihoods, increased agricultural production and sustainable socio-economic development. However, the activities of these stakeholders in the climate change arena appeared isolated, disjointed and uncoordinated to reap desired benefits. In response, the CCAFS programme in West Africa coordinated by ICRISAT, Bamako involving Ghana, Mali and Senegal was able to set up national multi-stakeholder platforms for information sharing and learning on climate change and related policy issues. The Ghana CCAFS Science-Policy Dialogue Platform having been operational since November 2012 has wealth of experiences to share. This note is therefore designed to highlight the profile of Ghana’s platform, its structure and composition and the key achievements over the past 4-5 years of existence

Comparing health workforce forecasting approaches for healthcare planning: The case for ophthalmologists

Health workforce planning is essential in the provision of quality healthcare. Several approaches to planning are customarily used and advocated, each with unique underlying assumptions. Thus, a thorough understanding of each assumption is required in order to make an informed decision on the choice of forecasting approach to be used. For illustration, we compare results for eye care requirements in Singapore using three established workforce forecasting approaches – workforce-to-population-ratio, needs based approach, utilization based approach – and a proposed robust integrated approach to discuss the appropriateness of each approach under various scenarios. Four simulation models using the systems modeling methodology of system dynamics were developed for use in each approach. These models were initialized and simulated using the example of eye care workforce planning in Singapore, to project the number of ophthalmologists required up to the year 2040 under the four different approaches. We found that each approach projects a different number of ophthalmologists required over time. The needs based approach tends to project the largest number of required ophthalmologists, followed by integrated, utilization based and workforce-to-population ratio approaches in descending order. The four different approaches vary widely in their forecasted workforce requirements and reinforce the need to be discerning of the fundamental differences of each approach in order to choose the most appropriate one. Further, health workforce planning should also be approached in a comprehensive and integrated manner that accounts for developments in demographic and healthcare systems

Children's Medicines in Tanzania: A National Survey of Administration Practices and Preferences.

The dearth of age-appropriate formulations of many medicines for children poses a major challenge to pediatric therapeutic practice, adherence, and health care delivery worldwide. We provide information on current administration practices of pediatric medicines and describe key stakeholder preferences for new formulation characteristics. We surveyed children aged 6-12 years, parents/caregivers over age 18 with children under age 12, and healthcare workers in 10 regions of Tanzania to determine current pediatric medicine prescription and administration practices as well as preferences for new formulations. Analyses were stratified by setting, pediatric age group, parent/caregiver education, and healthcare worker cadre. Complete data were available for 206 children, 202 parents/caregivers, and 202 healthcare workers. Swallowing oral solid dosage forms whole or crushing/dissolving them and mixing with water were the two most frequently reported methods of administration. Children frequently reported disliking medication taste, and many had vomited doses. Healthcare workers reported medicine availability most significantly influences prescribing practices. Most parents/caregivers and children prefer sweet-tasting medicine. Parents/caregivers and healthcare workers prefer oral liquid dosage forms for young children, and had similar thresholds for the maximum number of oral solid dosage forms children at different ages can take. There are many impediments to acceptable and accurate administration of medicines to children. Current practices are associated with poor tolerability and the potential for under- or over-dosing. Children, parents/caregivers, and healthcare workers in Tanzania have clear preferences for tastes and formulations, which should inform the development, manufacturing, and marketing of pediatric medications for resource-limited settings

Biomass yield and fodder quality of Napier grass (Pennisetum purpureum) as affected by Pigeon pea (Cajanus cajan) intercrop and planting distance

The study sought to investigate the effect of two planting distances and Pigeon Pea (Cajanus cajan) intercrop on the biomass yield, chemical composition and in vitro organic matter digestibility (IVOMD) of Napier grass (Pennisetum purpureum). The treatments were laid in a 2x2 factorial RCBD. The factors were two planting distances (0.5x0.5 and 0.5x1m) and two levels of intercrop (Pigeon Pea intercrop and sole Napier grass). At 90-days, the grasses were harvested and biomass yield measured. The fodder was separated into leaves and stems for chemical and digestibility analysis in 2x2x2 factorial in CRD. The interaction at all levels was not significant for all the parameters. There was a significant main effect of planting distance, intercrop and botanical fraction on biomass yield, plant height, tiller number and fodder quality. Whilst biomass yield was higher (P=0.02) in the 0.5x0.5m, no significant difference was recorded in the effect of the intercrop. Whilst intercrop affected (P<0.05) IVOMD and ME, botanical fraction significantly affected DM, CP and ME. The leaf fraction had more (P<0.05) DM, CP and ME than the stem fraction. The study revealed that close planting distance enhanced biomass yield whilst Pigeon Pea intercrop and botanical fraction affected fodder quality of Napier grass

Effect of rumen content to water ratio in biogas production

Biogas technology is widely used as a better alternative in the handling of waste in many societies in the world. This study was conducted to investigate the effect of rumen content to water ratio in biogas production. An experiment was carried out using 75 litre capacity locally made anaerobic digester. Rumen contents were formulated in three proportions designated as T1, T2 and T3. T1 contained 30kg of rumen contents and 30 litres of tap water; T2 contained 20kg of rumen contents and 40 litres of tap water; and T3 contained 40kg of rumen contents and 20 litres of tap water. Each proportion was duplicated and the whole experiment was triplicated for 20 days each. The pH, substrate, ambient temperatures and the biogas produced were recorded in two days’ interval up to the 20 days. The result obtained from the study showed that there were significant differences (P < 0.05) in the average pH and the biogas produced. The pH of T2 (6.97) was significantly higher than that of T1 (6.80) and T3 (6.81). The biogas produced by T3 was significantly higher than that of T1 and T2. T3 produced the highest average volume of 16.70m3 biogas per kilogram of rumen content and the highest percentage (56.4%) of methane. There were no significant differences (P > 0.05) in the average substrate and ambient temperatures, and the volume of CO2 produced. This study revealed that it is more efficient to produce biogas using 40kg of rumen contents and 20 litres of tap water than producing biogas with 30kg of rumen contents and 30 litres of tap water or 20kg of rumen contents and 40 litres of tap water.Keywords: biogas, pH, rumen, temperature, wate

Improved forage cultivation for increased in fodder availability and climate change mitigation in the Savanna agro-ecological zone of northern Ghana

The study was conducted to investigate the biomass yield and quality of two forage species Brachiaria ruziziensis (B. ruziziensis) and Sorghum almum (S. almum) in a Randomized Complete Block Design (RCBD) in two different locations (Bihinayili in the Savelugu District and Zanlerigu in the Nabdam District) in the Savanna agro-ecological zone of Ghana. Agronomic data were collected and representative samples of forage biomass taken at 60 days after planting to estimate dry matter yield and nutritive quality. The two-way interaction effect of forage species and experimental site was not significant for both agronomic and chemical parameters except for tiller number. The average leaf size was broader (P=0.006) in S. almum (299.0 cm2) than B. ruziziensis (85.0 cm2). Number of leaves per plant was higher (P=0.016) in B. ruziziensis (10.75). Number of tillers per plant in B. ruziziensis (9.62) was higher (P=0.001) than S. almum (2.88). Plant height was however, higher in S. almum (183.1 cm) than B. ruziziensis (90.1 cm). Dry matter yield of forages at 60 days after planting was higher (P<0.001) at Bihinayili (8.49 tons/ha) than that at Zanlerigu (2.23 tons/ha). The CP content of the forages at Bihinayili (89.7 g/kg DM) was also higher (P=0.018) than that at Zanlerigu (68.6 g/kg DM). Dry matter yield of B. ruziziensis (4.84 tons/ha) did not differ significantly from that of S. almum (5.88 tons/ha). In conclusion, B. ruziziensis and S. almum performed well within the Savanna agroecological zone and could enhance fodder supply and carbon sequestration