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Perovskite solar cells (PSCs) have gained a lot of attention due to their high efficiency and low cost. In this research paper, a methylammonium tin iodide (CH3NH3SnI3) based solar cell was simulated using a one-dimensional solar cell capacitance simulation (SCAPS-1D) tool. The SCAPS-1D tool is based on Poisson and the semiconductor equations. After thorough investigation, the initial device presents the following parameters; power conversion efficiency (PCE)=15.315%, fill factor (FF)=64.580%, current density (Jsc)=29.152 mA/cm2, and open circuit voltage (Voc)=0.813 V. The effect of absorber and ETL thicknesses were explored systematically. The performance of the simulated device was significantly influenced by the thickness of the absorber and ETL. The optimized absorber thickness was 0.5 µm and the ETL thickness was 0.02 µm, giving rise to an optimized PCE of 15.411%, FF of 63.525%, Jsc of 29.812 mA/cm2, and Voc of 0.814 V. Additionally, the effect of temperature on the optimized device was evaluated and found that it affects the performance of the device. This model shows the prospect of CH3NH3SnI3 as a perovskite material to produce toxic-free environment-friendly solar cells with high efficiency.

Many nations have long been actively supporting the development of electric vehicles (EVs). The adoption of the sustainable development goals (SDGs) actions in that direction have been accelerated to ensure that the 24% of the CO2 emission of the transport sector is brought down to the barest minimum. The focus of this paper is on the necessary measures and effective ways of acquiring EV technologies for developing countries such as Nigeria. The steps needed towards the development of the EV sector in Nigeria and the research and development strategies needed to address the challenges facing Nigeria in its quest to build a formidable EV industry are x-rayed. Finally, the opportunity for energy diversification towards confronting the challenges occasioned by inadequate electricity supply and distribution on the EV value chain is identified and analysed with recommendations made on the way forward. Since the EV industry cannot be true of zero-emission until its source of electricity is of zero-emission, the inherent potentials of using renewable electricity in the form of hydrogen fuel cells and harnessing the potential for solar photovoltaics (PV) of about 210 GW and concentrated solar power of approximately 88.7 GW is highlighted and recommended for the evolving EV market in Nigeria.

The development of efficient metal doped semiconductors for Photovoltaic applications has gained a lot of research attention. In this present paper, pure and silver nanoparticles (AgNPs)-modified TiO2 nanocrystals (NCs) with different amount of AgNPs (say 50, 100, 150, 200, and 250 µL) were achieved and the effects of AgNPs on the TiO2 NCs were explored systematically. The optical, structural and morphological properties were probed using UV-visible spectrophotometer, X-ray diffraction (XRD), and scanning electron microscope (SEM). The results of the optical studies showed a characteristic peak of TiO2 and the redshifting of the peak position was observed by introducing AgNPs. The synergetic effects from AgNPs and TiO2 results to diminished band gap. The XRD result confirmed the formation of a tetragonal anatase TiO2 phase with a decrease in crystallite size with increasing AgNPs content. The SEM images show enhanced nucleation and film growth with presence of shining surface which can be seen to contribute to good photon management by enhancing light scattering. The unadulterated TiO2 and AgNPs-modified TiO2 have spherical morphology and uniform size distribution ranging from 20 to 30 nm. This study established the view that surface modification of TiO2 with AgNPs is a viable approach towards achieving an efficient light photocatalyst.

Perovskite solar cells have garnered significant attention from solar cell researchers due to their potential for achieving high efficiency, primarily attributed to their exceptional Electron Transport layer (ETL). One of the key elements of perovskite solar cells for transporting electrons to generate current is the ETL material. Moreover, there is a promising avenue for enhancing stability and reducing fabrication costs by substituting the transport layer. In this study, TiO2 and SnO2 were used as ETL materials in the architecture of perovskite solar cells for a comparative analysis between two devices featuring distinct structures: TiO2/CH3NH3PbI3/Spiro-OMeTAD and SnO2/CH3NH3PbI3/Spiro-OMeTAD. To evaluate the performance of each electron transport layer (ETL), the SCAPS 1D tool was employed. The investigation involved varying the thickness of the electron transport layers, interface defect density and working temperature, allowing for a comprehensive assessment of key parameters such as voltage at open circuit (Voc), short circuit current density (Jsc), fill factor (FF), and overall efficiency (PCE%). Remarkably, when employing SnO2 as the ETL, the achieved efficiency stands at 10.10 %. In contrast, utilizing TiO2 as the ETL yields a slightly higher efficiency of 12.84%. These findings underline the nuanced influence of transport layer materials on the overall performance of perovskite solar cells.

The rise of the Internet of Things (IoT), marked by unprecedented growth in connected devices, has created an insatiable demand for supplementary computational and communication resources. The integration of Unmanned aerial vehicles (UAVs) within IoT ecosystems presents a promising avenue to surmount these obstacles, offering enhanced network coverage, agile deployment capabilities, and efficient data gathering from geographically challenging locales. UAVs have been recognized as a compelling solution, offering extended coverage, flexibility, and reachability for IoT networks. Despite these benefits, UAV technology faces significant challenges, including limited energy resources, the necessity for adaptive responses to dynamic environments, and the imperative for autonomous operation to fulfill the evolving demands of IoT networks. In light of this, we introduce an innovative UAV-assisted data dissemination framework that aims to minimize the total energy expenditure, considering both the UAV and all spatially-distributed IoT devices. Our framework addresses three interconnected subproblems: device classification, device association, and path planning. For device classification, we employ two distinct types of deep reinforcement learning (DRL) agents—Double Deep Q-Network (DDQN) and Proximal Policy Optimization (PPO)—to classify devices into two tiers. To tackle device association, we propose an approach based on the nearest-neighbor heuristic to associate Tier 2 devices with a Tier 1 device. For path planning, we propose an approach that utilizes the Lin-Kernighan heuristic to plan the UAV’s path among the Tier 1 devices. We compare our method with three baseline approaches and demonstrate through simulation results that our approach significantly reduces energy consumption and offers a near-optimal solution in a fraction of the time required by brute force methods and ant colony heuristics. Consequently, our framework presents an efficient and practical alternative for energy-efficient data dissemination in UAV-assisted IoT networks.

Background and Aim: One Health (OH) approach is crucial for the effective management of emerging and re-emerging infectious diseases and other public health threats. A meta-analysis was conducted to explore the benefits and challenges encountered in the practical implementation of multisectoral coordination in the fight against public health threats and to identify similarities between countries in the practical implementation of multisectoral coordination and cooperation across sectors in OH. Materials and Methods: To identify relevant studies published globally between 2010 and 2023, a literature search was conducted online using Google Scholar and PubMed search engines. Inclusion criteria were adopted based on key search terms “One Health,” “multisectoral coordination,” “One Health framework,” and related terms “multisectoral collaboration” and “multidisciplinary.” Unpublished manuscripts, dissertations, and conference reports were excluded from the review. A total of 307 articles were retrieved. Titles, abstracts, and keywords were screened for inclusion criteria. We extracted and analyzed 46 full-text articles published in English. Unpublished manuscripts, dissertations, and conference reports were excluded from the study. Results: This study found that most countries have similar challenges that hamper the coordination of OH activities implementation. Of the 46 articles reviewed, 69.6% (n = 32) focused on the benefits of adopting the OH approach and 73.9% (n = 34) focused on multisectoral coordination and collaboration among sectors. In addition, 58.7% (n = 27) of the articles indicated that governments need to invest more resources in OH implementation, and 50% (n = 23) proposed that policies, guidelines, and plans should be integrated to facilitate multisectoral coordination and collaboration. In addition to inadequate coordination and funding, other reported challenges were limited knowledge (34.8%) (n = 16) and inadequate resources (32.6%) (n = 15). In addition, 21.7% (n = 10) highlighted different sectoral priorities and interests as obstacles to effective coordination in the implementation of OH activities. Conclusion: Multisectoral coordination plays a key role in the effective management of public health threats through OH. The creation of mechanisms for regular communication, the promotion of mutual trust, and the strengthening of relations between sectors will enhance cooperation. The similarity in challenges across regions observed in this study calls for countries across regions to prioritize OH operationalization and collaboration among sectors, strengthen collaboration, and synergize activities to enhance future changes in the mitigation of public health threats.

Abstract Citizen science projects are expanding globally, with the African continent, particularly Nigeria, registering significant growth. Here, we document and analyse novel operations of the Nigerian Bird Atlas Project (NIBAP), 2015–2022. This project has employed the use of ornithologists, mainly trained at the A. P. Leventis Ornithological Research Institute (APLORI) located in Jos, Nigeria, and its 28 bird clubs established across Nigeria to enlist 827 bird enthusiasts that contribute regular and near real‐time data about bird distribution and relative abundance in the country. Interestingly, NiBAP has recorded about 75% of the bird species known from Nigeria in only about 50% of Nigeria's total surface area, including 39 nationally threatened species. The Common Bulbul Pycnonotus barbatus, Laughing Dove Spilopelia senegalensis, and Grey‐backed Camaroptera Camaroptera brevicaudata were the most commonly recorded species, while Amurum Forest Reserve, Rennajj Fish Farm, and Obudu Cattle Ranch were the most surveyed sites during the period. Thus, our approach reveals how to increase involvement of nature enthusiasts, ornithologists, and a regional research institute to build local capacity and contribute rich information necessary to alleviate the lack of distributional data about Afrotropical avifauna. We strongly recommend our approach to boost other citizen science projects across Africa and beyond to address the huge lack of biodiversity data, create public awareness, and foster conservation education.

Photovoltaic technology has been widely recognized as a means to advance green energy solutions in the sub-Saharan region. In the real-time operation of solar modules, temperature plays a crucial role, making it necessary to evaluate the thermal impact on the performance of the solar devices, especially in high-insolation environments. Hence, this paper investigates the effect of operating temperature on the performance of two types of organometallic halide perovskites (OHP) - formamidinium tin iodide (FASnI3) and methylammonium lead iodide (MAPbI3). The solar cells were evaluated under a typical Nigerian climate in two different cities before and after graphene passivation. Using a one-dimensional solar capacitance simulation software (SCAPS-1D) program, the simulation results show that graphene passivation improved the conversion efficiency of the solar cells by 0.51 % (FASnI3 device) and 3.11 % (MAPbI3 device). The presence of graphene played a vital role in resisting charge recombination and metal diffusion, which are responsible for the losses in OHP. Thermal analysis revealed that the MAPbI3 device exhibited an increased fill factor (FF) in the temperature range of 20–64 °C, increasing the power conversion efficiency (PCE). This ensured that the MAPbI3 solar cell performed better in the city and the season with harsher thermal conditions (Kaduna, dry season). Thus, MAPbI3 solar cells can thrive excellently in environments where the operating temperature is below 65 °C. Overall, this study shows that the application of OHP devices in sub-Saharan climatic conditions is empirically possible with the right material modification.

Telecommunications plays a crucial role in facilitating the transmission of voice, data, and multimedia over extended distances. This paper explores the significance of telecommunications, particularly in Nigeria, the largest ICT market in Africa, where telecom and internet usage hold substantial importance. However, the sector's heavy reliance on fossil fuels has resulted in environmental challenges. This research underscores the imperative to transition to clean energy sources, aligning with the commitment of the Nigerian Communications Commission. The paper presents a case study of a solar hybrid system designed to enhance Base Transceiver Station (BTS) coverage, emphasizing notable challenges such as elevated costs and the industry's familiarity with fossil fuels. The optimal power configuration for a BTS, as identified in the study, features a 16kW PV (photovoltaic) array, 14kW Diesel Generator (DG), 32kWh Battery Energy Storage System (BESS), and Utility, achieving the lowest Levelised Cost of Energy (LCOE) at $0.255/kWh. The production summary for the Solar PV array is 24,767 kWh/year (76%), the Diesel Generator is 1,250 kWh/year (4%), and the Utility is 6,503 kWh/year (20%). Consequently, the total estimated production is 32,520 kWh/year, constituting 100% of the energy requirement for the BTS. The study proposes solutions to challenges, including local clean energy component production, capacity building, and regulatory alignment. In conclusion, the adoption of clean energy is deemed essential for sustainability, with recommendations for policy adoption and efficient equipment utilisation.

The existing methods of callose quantification include epifluorescence microscopy and fluorescence spectrophotometry of aniline blue-stained callose particles, immuno-fluorescence microscopy and indirect assessment of both callose synthase and β-(1,3)-glucanase enzyme activities. Some of these methods are laborious, time consuming, not callose-specific, biased and require high technical skills. Here, we describe a method of callose quantification based on Sandwich Enzyme-Linked Immunosorbent Assay (S-ELISA). Tissue culture-derived banana plantlets were inoculated with Xanthomonas campestris pv. musacearum (Xcm) bacteria as a biotic stress factor inducing callose production. Banana leaf, pseudostem and corm tissue samples were collected at 14 days post-inoculation (dpi) for callose quantification. Callose levels were significantly different in banana tissues of Xcm-inoculated and control groups except in the pseudostems of both banana genotypes. The method described here could be applied for the quantification of callose in different plant species with satisfactory level of specificity to callose, and reproducibility. Additionally, the use of 96-well plate makes this method suitable for high throughput callose quantification studies with minimal sampling and analysis biases. We provide step-by-step detailed descriptions of the method.

The objective of this study is to examine the potential product yields and energy recovery of maize cobs (MC) through carbon dioxide-assisted torrefaction using thermogravimetric analysis (TGA). The CO2-assisted torrefaction of MC was performed from 240 °C to 300 °C (Δ 30 °C) for the residence time of 30 minutes based on the selected non-isothermal/isothermal heating program of the TGA. Furthermore, the physicochemical, microstructure and mineral characteristics of MC were examined. The results showed that the CO2-torrefaction of MC resulted in a mass loss (ML) ranging from 18.45% to 55.17%, which resulted in the mass yield (MY) ranging from 81.55% to 44.83%. The HHV of the solid product was in the range from 22.55 MJ/kg to 26 MJ/kg, which indicates the CO2-torrefaction process enhanced the energy content of MC by 40% – 60%. In conclusion, the findings showed that the CO2 torrefaction is a practical, sustainable, and cost-effective approach for the valorization of MC into a clean solid biofuel for enhanced energy recovery.

In this paper, a new derivative-free approach for solving nonlinear monotone system of equations with convex constraints is proposed. The search direction of the proposed algorithm is derived based on the modified scaled Davidon-Fletcher-Powell (DFP) updating formula in such a way that it is sufficiently descent. Under some mild assumptions, the search direction is shown to be bounded. Subsequently, the convergence result of the proposed method is established. The performance of the proposed algorithm on a collection of some test problems as well as signal recovery problems is demonstrated in comparison with some existing algorithms with similar characteristics. The results of the numerical experiments confirm the efficiency as well as the robustness of the proposed algorithm by comparing it with some existing methods in the literature.

We derive a deterministic mathematical model that scrutinizes the dynamics of cholera pathogen carriers and the hygiene consciousness of individuals, before the illness, during its prevalence, and after the disease's outbreaks. The dynamics can effectively help in curtailing the disease, but its effects had less coverage in the literature. Boundedness of the solution of the model, its existence, and uniqueness are ascertained. Effects of cholera pathogen carriers and hygiene consciousness of individuals in controlling the disease or allowing its further spread are analyzed. The differential transformation method is used to obtain series solutions of the differential equations that make the system of the model. Simulations of the series solutions of the model are carried out and displayed in graphs. The dynamics of the concerned state variables and parameters in the model are interpreted via the obtained graphs. It is observed that higher hygiene consciousness of individuals can drastically reduce catching cholera disease at onset and further spread of its infections in the population, this in turn, shortens the period of cholera epidemic. [ABSTRACT FROM AUTHOR]