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Late presentation of congenital diaphragmatic hernia (CDH) presents usually after the neonatal period and often misdiagnosed for other respiratory pathologies. It is crucial to differentiate late presentation of CDH from other potential causes of respiratory distress and gastrointestinal symptoms. Herein, we present 2 cases of delayed presentation of congenital diaphragmatic hernia in infants. Initially, both cases were managed as respiratory conditions in outpatient settings, with no significant improvement. The correct diagnosis was eventually made through radiological evaluation at our tertiary centre, leading to successful surgical management. Delayed presentation of CDH beyond the neonatal period is rare, owing to the wide spectrum of clinical manifestations. Early diagnosis and surgical management are crucial to reduce morbidity and mortality, making a high index of suspicion essential for timely intervention.

BACKGROUND: Tirofiban has been shown to be superior to aspirin in achieving functional independence at 3 months for acute ischemic stroke of atheromatous or microatheromatous origin. As intravenous thrombolysis (IVT) has previously been shown to be nonsuperior to aspirin in achieving functional independence at 3 months for anterior choroidal or paramedian pontine infarction (ACI/PPI), we aimed to compare the outcomes of Caucasian patients receiving IVT plus tirofiban (IVT + T) with those receiving tirofiban alone for acute ACI/PPI. METHODS: A retrospective study was conducted in patients aged ≥ 18 years with ACI/PPI treated in our stroke unit between December 1, 2020, and April 30, 2023, who received therapeutic intervention within 9 hours of symptom onset or after awakening with stroke symptoms. Modified Rankin Scale (mRS) ≤ 1 at 3 months was the primary endpoint. Secondary endpoints were National Institutes of Health Stroke Scale (NIHSS) ≤ 2 at day 7 or discharge and post-procedural neurological deterioration (PPND) within 72 hours. Symptomatic intracranial hemorrhage (SICH) and major systemic bleeding (MSB) were the safety measures of the study. RESULTS: A total of 24 patients were enrolled in the tirofiban group and 43 patients in the IVT + T group. Compared to tirofiban alone, IVT + T was associated with a higher probability of achieving mRS ≤1 at 3 months (adjusted odds ratio [aOR], 8.79; 95% confidence interval [CI], 2.06–37.52; P = 0.003) and National Institutes of Health Stroke Scale ≤2 at day 7 or discharge (aOR, 3.70; 95% CI, 1.05–12.99; P = 0.041). No significant difference was seen between the two groups in preventing postprocedural neurological deterioration. One case of SICH and two cases of MSB occurred in the IVT + T group and no cases in the tirofiban group. One case of inhospital mortality was recorded in the IVT + T group. CONCLUSIONS: Our results showed that IVT + T may be safe and effective in Caucasian patients with acute ACI/PPI.

In order to achieve a sustainable, low-carbon energy future, it is necessary to develop innovative and integrated solutions. However, one of the main obstacles to the advancement of renewable energy is storage. With this in mind, hybrid systems combining solar energy and hydrogen production have great potential. This article focuses on the evaluation of a solar PV/T (photovoltaic-thermal) system coupled with an electrolyser for the joint production of hydrogen and heat. Simulations are performed in MATLAB. The analysis reveals that with PV/T power supply, the production potential is estimated at 179.6 W and 551.9 W respectively for electrical and thermal power. An in-depth study aimed at optimizing the system by evaluating the quality of the energy used in the water electrolysis process makes it possible to analyze the effect of certain operating parameters. With a water flow of 5.7 ×10−3 m3/h, a current density of 200 mA/ cm2 and an electrolyzer temperature of 60 °C, the monthly production of hydrogen and oxygen reaches the maximum values of 4.85 m3 and 2.42 m3 respectively. This led to a maximum exergy efficiency of 57.8 %. This study demonstrates the linearity between hydrogen production and current density which at high density reduces exergy performance.

This article presents the suitability analysis of onshore wind farm sites using an AHP (Hierarchical Analysis Process) multi-criteria decision-making (MCDM) approach based on geographic information system modeling (GIS). It is based on different technical aspects (wind speed, elevation, slope), economic (proximity to the electricity network, proximity to roads) and social (proximity to residential areas, population density). The introduction of the factor “population density” and the constraint “required area” rarely used in previous studies makes it possible to refine the results. The data is classified into several categories in a gradual manner, namely unsuitable (0); less suitable (1); suitable (2); highly suitable (3) and most suitable (4). The results show us that the largest percentage relating to spatial coverage is observed in the “suitable” range with 50.89 % and the corresponding theoretical wind power potential (TWPP) is 1377.926 GW; it is followed by “highly suitable” 5.67 % and a TWPP of 153.652 GW; then “less suitable” with 1.04 % and a TWPP of 28.163 GW. No areas were identified in “most suitable” and finally the “unsuitable” range with 42.4 %. Also, the most favorable areas are located in the part of the far north of the country corresponding to the strong wind zone. The sensitivity analysis was carried out based on scenario tests (technical, economic and equal-weight) in order to give greater visibility of choice to the different stakeholders who would like to invest in onshore wind energy in Cameroon. Furthermore, a study of hybrid solar-wind systems could improve the efficiency of electricity parks in Cameroon.

An effective teaching contributes to the students' performance and this depends on qualified-trained teachers, school administration, parents and conducive environment for teaching and learning. It is proven that students are more successful in their academic achievements, in the societies where teachers perceive their profession as their job. This paper explores the impact of the society's perception on teachers' professionalism. The method employed in this paper is qualitative by using interview technique and used audio-recorded to ensure a complete transcript. The result indicated that in some developing countries including Cameroon, Kenya and Fiji has various reasons for their job. Teaching profession was affected by how the society considers teachers whereby they are perceived as disadvantaged population who cannot fully take part in the social and economic activities due to the fact that their salary is very low compared other public servants. This low salary and loss of respect of teachers by the society lead to the job dissatisfaction and made the teaching profession as a transitional job before waiting to move to another different professional field.

With the aim of diversifying different energy sources and achieving net zero emissions, hybrid renewable energy sources (HRES) represent the future of the world. However, several HRES simulation software do not integrate the Photovoltaic/thermal (PV/T) system. This article designs an optimal design model for a tri-hybrid Photovoltaic/thermal/hydroelectric (PV/T/H) system for a rural locality in the North Cameroon region. The two Demand Side Management (DSM) strategies used reveal that the DSM strategy significantly reduced the energy cost by 59 % and the emission by CO2 22 % compared to the No-DSM mode. Although the use of battery storage (BSS) is used in both cases, the optimal solutions obtained thanks to the multi-objective optimization method implemented on Matlab led to 418 PV/T panels, 2 MH generators, 2 diesel generators (DG) and 217 PV/T panels and 1 DG for DSM and No-DSM mode respectively. This study is a demonstration of the effect of dynamic tariffs and active demand management technologies on PV/T/H modeling and optimization. It also reveals the need to hybridize PV/T with other energy systems to increase performance and achieve net zero emissions.

The Stirling refrigerator is a device capable of using green energies such as solar power. In this work, a refrigerator-Stirling/photovoltaic system is proposed to harness solar energy for cold production. The system consists of photovoltaic (PV) panels that capture solar energy and convert it into electricity, and a transmission belt linking the motor to the Stirling beta refrigerator to use the electricity for cooling purposes. The system is modeled on the basis of finite-dimensional thermodynamics, taking into account the refrigerator's internal and external irreversibilities. In addition, the wiring loss, dust coverage and shading of the photovoltaic system and the mechanical power loss of the Stirling refrigerator are taken into account in this model. Power equality has been considered as a system constraint. Finally, the effects of operational and design parameters on system performance are investigated. A numerical code is written in Matlab. The effects of PV module efficiency, Stirling regenerator efficiency and PV derating factor on system performance are quantified, also the optimum operating parameters obtained. The refrigerator-Stirling/photovoltaic has a high COP and a low cooling capacity, in contrast to the refrigerator-Stirling/Dish-Stirling. The optimum solar electric COP and maximum cooling rate are 0.7063 and 1413 W respectively at an optimum panel area of 2 m2. Optimum exergy efficiency is 38.5 % at fv = 0.1, ecological coefficient of performance (ECOP) is 20.3 % at N = 48 rot.s−1, optimum exergy destroyed is 33.31 W at K1 = 21.5 W.K−1. This system can be used to preserve vaccines in hospitals.

The use of nanofluids (NFs) as heat transfer fluids (HTFs) is one way of improving the thermal performance of parabolic trough solar collectors (PTSCs). This study presents a comparative analysis of the thermal performance of a PTSC using nanofluids as HTF. Two categories of nanoparticles (NPs) (green and conventional) and two base fluids (water and Syltherm 800) giving eight nanofluids are used in a one-dimensional quasi-static thermal model, simulated from a numerical code written in Matlab. After numerical validation of the proposed model, the comparative analysis in static and dynamic regimes linked to solar radiation shows that green NPs present not only differentiated positive but also negative effects on thermal performance depending on the base fluids compared to conventional NPs, and that the combination of green nanoparticles with high thermal capacity base fluids presents more positive than negative thermal effects. The impact of conventional NPs is more significant with water, at around 0.005 MWh, than with Syltherm 800, which averages around 0.002 MWh. The use of HTF configurations based on Syltherm 800 increases production by around 1 MWh more than that of water. HTF configurations based on Syltherm 800 generate around $0.004/kWh less than water on average. HTFs based on Syltherm 800 produce around 7.5 kgCO2/year more than water.

Background: The hemodynamic performance of cardiovascular medical devices and their potential to cause blood damage are critical factors in ensuring patient safety and device efficacy. Computational Fluid Dynamics (CFD) has emerged as a valuable tool for simulating blood flow within these devices and predicting the risk of blood damage.Objective: This study aims to utilize CFD simulations to evaluate the local hemodynamic performance of a particular implantable device and to provide precise predictions about likely adverse clinical effects, cutting-edge techniques like LDA or PIV must be accessible.Methods: A patient-specific CFD model of the cardiovascular system and medical devices was developed based on medical imaging data. Hemodynamic parameters such as shear stress and flow recirculation were computed to identify regions of potential blood damage. The simulations were validated against data.Results: The CFD simulations revealed intricate flow patterns and areas of concern within the medical devices. Elevated shear stresses and prolonged residence times were identified in certain regions, indicating a risk of blood damage (Figure 2). By quantifying these parameters, the study provided a comprehensive assessment of potential blood damage locations and severity levels.Conclusion: Computational Fluid Dynamics proved to be a robust approach for evaluating blood flow within cardiovascular devices and predicting potential blood damage. The study highlighted specific design modifications that could mitigate the risk of blood damage, thus contributing to the improvement of device safety. The integration of CFD with patient-specific data offers clinicians and engineers a powerful tool for optimizing cardiovascular device design and minimizing patient risk.

Abstract Hybrid PV/T (Photovoltaic/thermal) systems are a robust alternative to the limitations of PV panels and thermal collectors in energy production. Improving their performance is therefore necessary. This article presents a new configuration of hybrid photovoltaic and thermal (PV/T) air/water-CuO/MgO/TiO2 collector which is optimized by seeking a better combination of design parameters which maximize the exergy performance. An energy and exergy analysis of the system is carried out and a multi-objective optimization with the genetic algorithm is developed using Matlab. These to determine the values of these nine (9) design parameters such as collector tilt angle, collector area, center to center distance between tubes, inside and outside diameter of tubes and thicknesses of the cells, of the glass layer, of the insulation, of the absorber. The other parameters are taken constant and a set of optimal solutions are sought for 1000 generations. The comparison of the different numerical results from this article with the design parameters from previous work shows good agreement. It is observed that the total exergy efficiency is maximum between the values of 23.41–36.6% and the majority of the design parameters studied in general are minimum. The discussions deduced that the minimization of the components of the bi-fluid PV/T hybrid collector could reduce the losses inside the latter by favoring the cooling as well as the displacement of the heat at the back of the PV cell. This work shows that the mixture of water and ternary nanoparticles with a flow rate of 0.00575 kg/s cooled more than air at 0.008 kg/s, but the system performed better when the two fluids operated simultaneously at 0.0035 kg/s. Due to the requirement of optimal efficiency and minimum costs, the hybridization of nanoparticles presents better thermo-economic performances.

Agricultural productivity in the Great Lakes Countries of Central Africa, including Burundi, Rwanda, and the Democratic Republic of Congo, is affected by a wide range of diseases and pests which are mainly controlled by chemical pesticides. However, more than 30% of the pesticides used in the region are banned in European Union due to their high toxicity. Globally available safe and eco-friendly biological alternatives to chemicals are virtually non-existent in the region. Bacillus PGPR-based biocontrol products are the most dominant in the market and have proven their efficacy in controlling major plant diseases reported in the region. With this review, we present the current situation of disease and pest management and urge the need to utilize Bacillus-based control as a possible sustainable alternative to chemical pesticides. A repertoire of strains from the Bacillus subtilis group that have shown great potential to antagonize local pathogens is provided, and efforts to promote their use, as well as the search for indigenous and more adapted Bacillus strains to local agro-ecological conditions, should be undertaken to make sustainable agriculture a reality in the region.

Photovoltaic/thermal (PV/T) hybrid systems have until now encountered a real problem of sustainability-energy-cost concordance. Faced with this situation, new types of designs are in full expansion aimed at filling the limits of some. This therefore involves a very appropriate decision-making process. The energy, exergy, economic, environmental, energo-environmental, exergo-environmental, enviro-economic, energy-enviro-economic, exergo-enviro-economic and ergonomic analysis is carried out on seven PV/T configurations and therefore the simplified models are presented for a better interpretation of the mechanisms from different perspectives and the integration of a selection algorithm. Thus, an optimal selection methodology using the hybridization of genetic algorithms and multi-objective optimization by particle swarms based on ten performance indicators is proposed. The results obtained with good convergence and precision allow us to observe that the Air PV/T model is better. However, the study shows good viability of PV/T models with a cost of energy and a return on investment time all lower than 0.1$/kWh and 3 years, respectively. Models with phase change materials (PCM) minimize thermal losses better than those with air, nanofluids or thermoelectric generator (TEG). The bifacial model stands out with a good energy-environmental balance compared to the water model which has a better durability index greater than 2.0 and a good ergonomic factor.

This paper aims to highlight the use of different heat transfer fluid (HTF) configurations based on vegetable oils in Parabolic Trough Solar Concentrator (PTSC). Rapeseed and jatropha oils as innovative heat transfer materials combined with SiO2 and Al2O3 to obtain six (6) HTF configurations are used in a 1-dimensional PTSC model. The thermophysical properties of the nanofluids are determined from correlations derived from the literature, using Gauss-Seidel method from a numerical code developed in Matlab software. Model validation is obtained. Thermal sensitivity analysis shows that the use of rapeseed increases the thermal efficiency of the PTSC by around 4.21 % compared with jatropha. The use of nanofluids reduces thermal losses within the system due to thermal gradients. For a fixed irradiance and each 1 %–4 % increase in volume fraction, thermal efficiency increases by around 1.96 % when Al2O3/rapeseed is used and by 0.47 % when SiO2/rapeseed is used compared with rapeseed. Similarly, thermal efficiency increases by around 1.98 % when Al2O3/jatropha is used and decreases by around 0.20 % when SiO2/jatropha is used compared with jatropha. However, the positive effects of nanoparticles on thermal conductivity alone are not always sufficient to improve thermal efficiency, and thermal effects on heat capacity should also be considered.

To assess the production potential, economic profitability and ecobalance of the photovoltaic/thermal (PV/T) system in Cameroon, different configurations of HTF based on water, vegetable and synthetic oils, coupled with different forms of titanium dioxide (TiO2) are used. A numerical code is written in Matlab. The PV/T model connected in direct contact PV-absorber is validated and a multi-objective optimization of the system is performed. The hourly evolution of PV cell temperature for the six HTF configurations revealed a value below 36 °C with Coton/TiO2. The platelets-and spherical-shaped nanoparticles increase the convection transfer coefficient between the fluids and the tubes. TiO2 showed a higher thermal influence in vegetable and synthetic oils than in water at a volume concentration of 4 %. The cotton/TiO2 configuration showed a 12.08 % improvement in electrical efficiency over conventional PV systems with low exergy efficiency compared to water. Configurations with therminolVP-1/TiO2 are better, with the proposed energy cost reduced to 33 % of the price of electricity in Cameroon. The PV/T-Palm/TiO2 system showed an energy cost of $0.03 with a net present value of $568.45, an emission rate of 7.78 kg, a reversibility index of 1.95, an annual cost of $7.07 and a payback time of 5.97yr. This shows that PV/T systems based on vegetable oils are economical.

Digital training plays a major role in the initial training for preschool, primary, and high school teachers in Québec, Canada. Since the mastery of information and communications technology (ICT) is prescriptive, measures have been implemented in university teacher training programs to ensure its development. Nevertheless, after this training, pre-service teachers' (PSTs') ability to transfer competency to a real context remains uncertain. We identified PSTs' levels of mastery of digital tools and competency, as well as their pedagogical usage of them during their school practicums. We sought to ascertain whether they were ready to organize collaborative learning activities with their students. Their mastery of digital tools did not go beyond the level of "good," except for tools related to office suites. They perceived themselves as having average mastery of the ability to integrate ICT. In addition, the transfer to a professional context is progressing "via" the pedagogical usage of ICT reported by PSTs during their school practicums. We observed moderate correlations between the mastery of collaborative and communication tools and of collaborative learning activities.

Abstract Health shocks are common and have serious consequences for households in developing countries where health insurance is lacking. In this study, we examine whether out-of-pocket health expenditures crowd out household consumption of non-healthcare necessities, such as education items in Benin using a sample of 14,952 households from the global vulnerability and food security analysis survey. We estimated a system of conditional Engel curves with three stage least squared (3SLS) and seemingly unrelated regression (SURE) for seven categories of goods using the Quadratic Almost Ideal Demand System (QUAIDS) in the form of budget shares corresponding to proportions of total non-health expenditure. Findings show that out of pocket health expenditure leads households to spend more on health care that in fine crowd out expenditure in other necessity goods such as education item. These findings highlight the need for social protection programs to mitigate the impact of health shocks on vulnerable households in Benin.