Unlocking Rural and Remote Coverage with Small Cells and Satellite

According to the Global System for Mobile Alliance (GSMA), in 2017, there were around 3.3 billion people connected to the mobile Internet. This represented an upward surge in global coverage compared to previous years. However, more than one billion people are still not covered by mobile broadband networks, representing what is termed “the coverage gap”. Uncovered populations typically live in rural locations with low population densities, low per-capita income levels and weak or non-existent enabling infrastructure, and thus, closing the mobile coverage gap seems to be more of an economic challenge, than a pure technical one. This paper presents an overview of the need for rural and remote coverage, both from an operator and consumer as well as government perspective. It then presents the major challenges, and necessary actions to be taken by industry, Government and other stake-holders to drive rural and remote coverage by significantly lowering the cost of network roll-out and increase incentives for such deployments. The paper therefore, presents a technical and business case for the use of “Small Cells” in conjunction with satellites with a view to opening up huge markets via collaboration between the mobile operators and satellite system owners, while offering significant improvements in the coverage and capacity needs of remote, rural or underserved end-users in a cost-effective and scalable manner. Detailed insights to these two technologies are presented, including the innovations to overcome technical and regulatory challenges. Lastly, some real-life deployments are given and the paper concludes with some recommendations for Government and network operators presente

Upgrading n-Heptane via Catalytic Hydroisomerisation

An atmospheric pressure upgrading of n-heptane was carried out in a temperature range of 300 to 450oC over an in situ developed molybdenum carbide phase supported over sulphated zirconia. Although a decreased in surface area with increased in pore volume were observed after carburization, the physicochemical data showed no noticeable alteration to the zirconia structure or the sulphate species. The catalyst formed a good system with high selectivity to iso-heptanes under either low temperature or high space velocity. It therefore has promising features that could offer mitigation to some of the challenges faced by the petroleum refineries with noble metals promoted zeolites. Keywords: n-heptane, hydroisomerisation, carbide catalyst, stability, sulphated zirconia

Production of Liquefied Petroleum Gas (LPG) Range Alkanes from n-Octane via Catalytic Hydroconversion

The production of light range alkanes with potentials as LPGs was carried out at 1 atm pressure over a range of reaction temperatures using both in situ and ex situ prepared molybdenum carbide supported sulphated zirconia catalysts. The in situ synthesized material formed the best system in terms of stability, conversion and selectivity to desired reaction products, as well as resistance to thermal treatment. This suggests its prospects as industrial material. Mechanistically, the reaction was believed to involved the participation of both the carbide and the sulphated zirconia surfaces via hydrogenolysis and hydrocracking, respectively. Reactions over the carbide formed mainly methane whereas propane and butanes could significantly be obtained over the sulphated zirconia. Keywords: n-octane, hydroconversion, light gases, fuel, prospect

Lessons learnt during the national introduction of human papillomavirus (HPV) vaccination programmes in 6 African countries: Stakeholders’ perspectives

Background. Infection with human papillomavirus (HPV) significantly increases the risk of developing cervical cancer later in life. Therefore, globally, HPV vaccines targeted to pre-adolescent and adolescent girls have been on the rise since the licensure in 2006. However, the introduction of HPV vaccines has been relatively slow in Africa. At the end of 2016, only 8 of the 54 countries in Africa were reported to have introduced HPV vaccination at a national level. By 2019, the number of countries had grown marginally to 11.Objectives. To investigate stakeholders’ perspectives on the experiences, challenges and lessons learnt during national HPV vaccine introduction in Africa.Methods. A questionnaire was administered to selected participants from 8 African countries. These countries had successfully introduced HPV vaccination at a national level by the end of 2016. We used in-depth interviews and self-administered online questionnaires for data collection and analysis. Data are presented without naming the country or participants; therefore, readers will not be able to identify the results that are specific to individual countries. Narrative and thematic reporting were used to describe the results.Results. We obtained results from 6 of the 8 targeted countries. The challenges reported during HPV vaccination programmes were: identifying the target population, using a school-based vaccine-delivery strategy, obtaining political support, the need to integrate HPV vaccination with existing school health programmes and engaging multiple stakeholders. These challenges were similar in all 6 countries. The lessons learnt were that a school-based delivery strategy is a successful approach for national HPV vaccination, and that identifying girls for vaccination at schools was less challenging if implemented through a class-based instead of an age-based approach.Conclusions. Most African countries do not have established platforms to deliver vaccines to pre-adolescent and adolescent populations. The successful introduction of the HPV vaccine through school-based vaccination strategies in African countries may have created a platform to deliver other adolescent vaccines. The similarity of the study findings across the 6 participating countries further strengthens the need to document and disseminate the challenges and lessons learnt during HPV vaccine introduction in Africa. Documentation and dissemination of the challenges and lessons learnt are useful to other countries in Africa that plan to introduce an HPV vaccination programme, and possibly other adolescent vaccines.

Accidental sulphuric acid poisoning in a newborn

A six hour old baby girl presented with shortness of breath and haematemesis five hours after accidental ingestion of sulfuric acid. We report the clinical presentation of corrosive ingestion in a neonate a rare and sparsely reported occurrence at such tender age.Key words: Acid ingestion, corrosives injuries, caustic substances, chemical ingestion, newborn

Identification of Radar Signals Based on Time-Frequency Agility using Short-Time Fourier Transform

With modern advances in radar technologies and increased complexity in aerial battle, there is need for knowledge acquisition on the abilities and operating characteristics of intercepted hostile systems. The required knowledge obtained through advanced signal processing is necessary for either real time-warning or in order to determine Electronic Order of Battle (EOB) of these systems. An algorithm was therefore developed in this paper based on a joint Time-Frequency Distribution (TFD) in order to identify the time-frequency agility of radar signals based on its changing pulse characteristics. The joint TFD used in this paper was the square magnitude of the Short-Time Fourier Transform (STFT), where power and frequency obtained at instants of time from its Time-Frequency Representation (TFR) was used to estimate the time and frequency parameters of the radar signals respectively. Identification was thereafter done through classification of the signals using a rule-based classifier formed from the estimated time and frequency parameters. The signals considered in this paper were the simple pulsed, pulse repetition interval modulated, frequency hopping and the agile pulsed radar signals, which represent cases of various forms of agility associated with modern radar technologies. Classification accuracy was verified using the Monte Carlo simulation performed at various ranges of Signal-to-Noise Ratios (SNRs) in the presence of noise modelled by the Additive White Gaussian Noise (AWGN). Results obtained showed identification accuracy of 99% irrespective of the signal at a minimum SNR of 0dB where signal and noise power were the same. The obtained minimum SNR at this classification accuracy showed that the developed algorithm can be deployed practically in the electronic warfare field for accurate agility classification of airborne radar signals

Waist Circumference, Waist Hip Ratio and Body Mass Index in Female Undergraduates of a Tertiary Institution in Nigeria: a Cross-sectional Study

Purpose: Obesity and overweight are associated with variety of conditions detrimental to health, wellbeing and longevity. Waist circumference and waist to hip ratio are indicators of risk of central adiposity while body mass index is an indicator of overall risk of obesity. Body mass index has been traditionally used as a standard for determining overweight and obesity. This study was designed to determine the relationship between waist circumference, waist to hip ratio and body mass index among female undergraduates of a Nigerian University. Also prevalence of obesity based on waist circumference, waist to hip ratio and body mass index was explored. Methods: Three hundred and sixty four apparently healthy subjects were recruited for the study using a cross-sectional simple random sampling technique. Waist circumference, waist to hip ratio and body mass index were determined using standard methods. Descriptive statistics were used to summarize the physical characteristics of the participants. Pearson correlation coefficient was used to analyze the relationship between waist circumference, waist to hip and body mass index. Results: The mean age, waist circumference, waist to hip ratio and body mass index of the participants were 22.5 (±2.20) years, 79.36 (±10.4) cm, 0.81 (±0.06), and 22.48 (±4.50) kg/m2 respectively. The prevalence of obesity based on body mass index, waist circumference and waist to hip ratio was found to be 6.3%, 17.6% and 25.5% respectively. Significant relationship was found between waist circumference and body mass index (r = 0.81; p\u3c 0.001), and between waist to hip ratio and body mass index (r = 0.25; p\u3c 0.001). Conclusions: Body mass index was related to waist circumference, as well as to waist to hip ratio. The prevalence of obesity based on waist to hip ratio was highest among female undergraduates in a Nigerian university. Awareness on the importance of waist to hip ratio as indicator of risk of obesity should be created among female undergraduates in Nigerian Universities and by extension among the women population in general

Effect of arbuscular mycorrhizal fungi and poultry manure on growth and nutrients contents of maize in different soil type

Public concerned about food safety and quality have raised interest in manipulating soil nutrients management strategies that could reduce potential threat on environment and sustain food production. Recently, the application of arbuscular mycorrhizal fungi (AMF)as bio-fertilizer has gained recognition especially, in low-input agriculture. The fungi are known to improve plant nutrition and growth. However, this effect may differ according to soil properties and nutrients concentration. A greenhouse experiment was conducted to investigate the effect of AMF and poultry manure (PM) on growth and nutrients contents in maize compared to chemical fertilizer; and to determine the effect of soil properties on colonization potential of AMF. The experiment consists of 13 treatments combinations in 2 soil types (loam and peat), viz; 6 application rates of composted PM in tones (t) ha-1 (0, 4, 6, 8, 10 and 12) and 2 levels of AMF; inoculated (+AMF) and un-inoculated (- AMF) plus recommended dose of NPK (RD NPK). Un-inoculated plants showed no symptoms of root colonization and recorded no AMF spore under both soils. Addition of PM stimulated AMF colonization and sporulation, the highest root colonization (RC %) and spore counts were recorded at 8 t PM+AMF under loam and 12 t PM+AMF in peat soils. Shoot dry biomass at 8 and 12 t PM+AMF under loam and peat were comparable to RD NPK. Applying 8 and 12 t PM+AMF in loam and peat recorded the highest N& K comparable to RD NPK. However, P content in shoot were statistically higher at 8,10 & 12 t PM+AMF in loam and at 12 t PM+AMF in peat compared to RD NPK. Application of 10 & 12 t PM+AMF in loam significantly decreased plant growth, lowered AMF RC%, and nutrient content (N & K). There was a strong positive correlation between shoot dry biomass and RC % in loam (R 2 = 0.740 P<0.01) and peat (R 2 =0.884 P<0.01). From the results of this study, it could be concluded that AMF have increased the efficiency use of PM and their integration have the potential to improve plant growth due to enhanced nutrients uptake and stimulated RC% in both soils. Results also indicated significantly higher shoot dry biomass, nutrients content (N, P, & K), spore counts and RC % in loam soil compared to peat, indicating that soil properties has a significant influence on effectiveness AMF

A Framework for Enhancing Contractor-Subcontractor Relationships in Construction Projects in Nigeria

The delivery capability of main contractors depends largely on the quality of their subcontractors and the harmonious relationships that exist between them. Research work was therefore conducted to identify the mechanisms to facilitate the understanding between these pairs and also develop a model that puts emphasis on the factors. To achieve this aim, one hundred questionnaires each were administered randomly to main contractors and labor-only subcontractors in the study area. Seventy-five and eighty-eight questionnaires were respectively filled and returned in this regard. The application of total weight value and rating index techniques shows that type of contract, scope of contract, payment terms, cooperative attitudes, third-party involvement are the main factors that influence this relationship and this was further validated by a model. The paper concludes that this methodology could culminate into a useful decision making tool for both main contractors and subcontractors during the development and execution stages of construction projects in the study area