Investigating the effect of High Altitude Platform Positioning on Latency and Coverage of 4G Cellular Systems

Wireless communication technologies are rapidly being adopted and developed by countries all over the world as a strategy for sustaining a digital economy. This has proven very useful for economic recovery from the crises brought about by the COVID-19 pandemic of the year 2020. The latency and coverage area of a wireless network are two major areas that are always seeking improvement. The High Altitude Platform communication technology can provide improvement in speed and coverage area for 4G cellular systems. This work investigated the effect of positioning High Altitude Platforms on the latency and coverage of 4G cellular Systems. A quantitative approach was used in the methodology of this paper. A HAP model showing a single platform flying in a circular trajectory over Base Transceiver Stations BTSs and serving as a relay mobile station was presented. A detailed simulation algorithm for the HAP and results for the simulation were given. Results showed that using the HAP as a relay mobile station in a network can give a latency reduction of up to 58.9%.  Also, the altitude of the HAP directly affects the angle of reception which was found to improve the coverage

Modelling of entrepreneurial leadership for effectiveness of schools

Entrepreneurial leadership practice is an exclusive leadership practice that aid in confronting the tasks and challenges of organizations. However many questions had been raised on the influence of the leadership style in the educational settings. This paper explained the concepts of entrepreneurial leadership, school effectiveness, dimensions of entrepreneurial leadership, the role of entrepreneurial leadership in achieving school effectiveness. And finally the implications of the paper to the body of knowledge, policy makers and school principals were discussed in the paper

Channel Propagation Characteristics on the Performance of 4G Cellular Systems from High Altitude Platforms (HAPs)

In this paper, we investigated the effect of different channel propagation characteristics on the performance of 4G systems from high altitude platforms (HAPs). The use of High-Altitude Platforms for communication purpose in the past focused mostly on the assumption that the platform is quasi stationary. The technical limitation of the assumption was that of ensuring stability in the positioning of the platform in space. The use of antenna steering and other approaches were proposed as a solution to the said problem. In this paper, we proposed a channel model which account for the motion of the platform. This was done by investigating the effect of Doppler shift on the carrier frequency as the signals propagate between the transmitter and receiver while the High-Altitude Platform is in motion. The basic free space model was used and subjected to the frequency variation caused by the continuous random shift due to the motion of the HAPs. The trajectory path greatly affects the system performance. A trajectory of 30km, 100km and 500km radii were simulated. An acute elevation angle was used in the simulation. The proposed model was also compared to two other channel models to illustrate its performance. The results show that the proposed model behave similar to the existing models except at base station ID 35 and 45 where the highest deviation of 20dBm was observed. Other stations that deviated were less than 2dBm

The Use of Information and Communication Technology (ICT) by Lecturers in North-Western Nigeria

Information and communication technology (ICT) encompasses all forms of technology deployed in information dissemination in contemporary societies. Several types of ICT products that can be found and having application to education, such as teleconferencing,  audio conferencing-mails, video lessons(TVs), radio broadcasts, interactive radio counselling, interactive audio response system, audiocassettes ,whatsapps  and CD ROMs, etc. are being used in education for many purposes. This paper determined the level of ICT usage among lecturers of federal universities in North-western Nigeria. A sample of 350 lecturers was randomly selected through a multi-stage cluster paradigm. Data was collected through online survey of adopted ICT perceive ease of use Questionnaire (IPEUQ) with a return response rate of 85.7%. The data was analysed using IBM SPSS software. Findings indicate that lecturers have personal commitment to acquire ICT skills in developing their competence, to the extent that they bear the cost of training without any intervention from the authorities. The paper therefore, concludes that, insufficiency of ICT facilities and highly trained personal in the universities leads to the low level ICT competence among lecturers. Keywords: ICT usage, lecturers, North-Western Universitie

Topical application of Acacia nilotica pods' water extract enhances wound healing in Sprague-Dawley rats by alleviating oxidative stress and suppressing pro-inflammatory cytokines

This study was conducted to validate the folkloric use of Acacia nilotica pods as wound healing agent. Full thickness excision wounds of 6mm diameter were created on Sprague-Dawley rats. Prior to the wound healing assessment, the antioxidant activity of the extract was determined in vitro using 2,2ꞌ- diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. Six groups of 6 wounded rats were formed. In each group, the wounds were topically treated with either petroleum jelly (vehicle control), silver sulfadiazine (positive control), 0.5%, 1% or 2% Acacia nilotica cream (treatment groups) prepared by mixing appropriate quantity of A. nilotica pods’ aqueous extract with petroleum jelly. The negative control group received no treatment. The wound healing parameters assessed include wound contraction rate, level of pro-inflammatory cytokines Interleukin1β (IL-1 β) and Tumor Necrosis Factor-α (TNF- α) and histopathological analysis of the wound area. Wounds were assessed on 7th and 14th post wounding days. The extract showed a good, dose dependent DPPH-radical scavenging activity comparable to trolox. Topical application of A. nilotica cream significantly (P< 0.05) enhances wound contraction rate compared to the control groups in both 7th and 14th days of evaluation. The extract also significantly suppressed the expression of both IL-1β and TNF-α in dose dependent manner throughout the study period. The histological analysis revealed that the extract treatment enhanced cellular proliferation as evident by the increased capillary vessels, re-epithelization and dermal tissues regeneration. Overall study suggest that A. nilotica pods’ water extract promotes wound healing in Sprague-Dawly rats by ameliorating oxidative stress and suppression of pro-inflammatory cytokines. This study validates the folkloric use of A. nilotica pods for postpartum wound healing for the first time. Further studies aimed at identifying and isolating active principles from this plant is recommended

E-band slotted microstip patch antenna array for 5G broadband applications

An antenna is one of solution for wireless devices which can be proposed for future 5G systems for high data rate broadband, communications. The antenna system can be design for multiple-input-multiple-output (MIMO) system at a waveband of millimeter (mm) range. The MIMO system consists of the mm-wave array of 2 by 1 slot antennas. The combination of the antenna array system covers the range of frequency from 83.581GHz to 86.483GHz of mm-wave band at 85 GHz. The antenna array dimension is 0.94 mm by 2.28 mm by 0.16 mm. Results obtained from simulation across the 5G band showed peak gain values of 5.82dBi, VSWR of 1.09 with -10dB return loss of -27.5dB

Heavy metal contents of sachet water in Gombe, Nigeria.

The provision of adequate clean drinking water is a basic human need in every society. In Nigeria, like many developing countries, the provision of clean drinking water is not adequate. The introduction of sachet water is seen by many as a solution to the problem. This is because it is affordable where more than a litter of it is sold at ten Naira or even less. The availability and affordability of sachet water have made it a preferred choice for most people despite questions being raised about the purity and potential toxicity. Objectives: To evaluate the heavy metal contents of sachet water in Gombe, Nigeria. Methodology: Forty samples of sachets water were bought randomly from the streets of Gombe and were analyzed for heavy metals content (lead, cadmium, mercury, arsenic and nickel) using Atomic Absorption Spectrophotometer (AAS). The data obtained were analyzed for frequencies and percentages for qualitative data and minimum and maximum for quantitative data using the system for statistical package for the social sciences (SPSS) version 20.00 for windows. Results: None of the sachet water samples had the date of manufacture or expiry date while about 23% had no National agency for food and drug administration and control (NAFDAC) registration numbers. All the samples had lead levels above the WHO safety limits of 0.01mg/L. Mercury, cadmium and arsenic levels were higher than the safety limits in 23%, 15% and 5% of the samples respectively. No nickel was detected in all the samples. Conclusion: The majority of the sachet water in Gombe is contaminated with heavy metals lead, mercury and cadmium in concentrations above the WHO safety limits. Processes of water purification should be put in place to reduce the heavy metal contents of sachet water in Gombe

Application of innovative teaching methods in teaching of entrepreneurship in the Nigerian polytechnichs

Entrepreneurship education is intended to communicate and instil skills, abilities, understanding, and values required to identify business opportunity, establish and start new business project. It involves translating an idea into reality. However, selecting the appropriate teaching methods required meeting up with the course objectives and the needs of the students had become a challenge to lecturers in the Nigerian Polytechnics. Thus, this paper discussed the concept of entrepreneurship education, entrepreneurship education in Nigeria, pedagogical approaches in teaching entrepreneurship education, and finally the implications of the paper on both the practitioners and policy makers were discussed

Andrographolide downregulates pro-inflammatory cytokines and free radical productions to prevent dopaminergic neuro-degeneration induced by lipopolysaccharide

Oxidative stress and inflammation triggers the production of free radicals and toxic pro-inflammatory cytokines leading to neurodegeneration. Down-regulation of oxidative stress and inflammatory mediators offers defence against development and progression of the disease. Andrographolide is the most abundant diterpene lactone isolated from the leaves of Andrographis paniculata. Despite the increasing literature studies on the anti-inflammatory effect of andrographolide, there is still paucity regarding its neuroprotective role as can be ascertained from the search of literature. The present study investigated the potential therapeutic role of andrographolide as a neuroprotective agent via in vitro model of lipopolysaccharide (LPS)-induced brain injury using microglial (BV2) and dopaminergic (N27) cells. Pre-treatment of andrographolide at non-cytotoxic concentration range (0.25-2.0 µM) of BV2 cells followed by LPS dose-dependently suppressed nitric oxide production, pro-inflammatory cytokines (TNF-α, IL-6) as well as attenuating intracellular reactive oxygen species (ROS) and thiobarbituric acid reactive substance (TBARS) compared to cells without andrographolide pretreatment. Further, conditioned media (CM) of the pretreatment had diminished toxicity towards dopaminergic neurons as compared to CM without pretreatment. Keywords: Andrographolide; Proinflammatory cytokines; oxidative stress; microglial; dopaminergic neurodegeneration