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This paper presents an analysis of the effect of two synthetic antioxidants on the vaporization processes of coconut and linseed oils for fuel use. Several studies agree on the effectiveness of synthetic or natural antioxidants against the polymerization of vegetable oils. The principle of action of the latter is to increase the rate of vaporization, to the detriment of polymer formation. The droplet suspension technique where a fiber is used to hold a stationary droplet has been used. The vaporization was conducted within a closed chamber under ambient pressure conditions in an inert and oxidizing environment at temperatures of 703 K. The method involves monitoring the projected surface area of vegetable oil droplet blended with antioxidants. The projected area (mm2) of the droplet during the vaporization process as a function of time (s) has been used to determine the vaporization coefficient, or the residue formation rate. The main findings are that the two antioxidants used at 200 ppm and 500 ppm have no influence on the vaporization of saturated oils like coconut, while on unsaturated oils like linseed the two antioxidants appear to reduce slightly the deposition of residues which are identified as polymers and increase slightly vaporization rate. In practice, antioxidants could be used as additives in vegetable oils to facilitate their combustion in diesel engines, representing a potential solution for improving combustion efficiency. To enhance the reliability of the findings, it would be advisable to increase the number of antioxidants and extend the study to encompass a wider range of vegetable oils.

Le présent travail vise à contribuer à une meilleure connaissance des déterminants de l’insertion professionnelle des étudiants en fin de cycle de l’Institut Burkinabè des Arts et métiers (IBAM). Deux enquêtes ont été réalisées auprès de cent (100) diplômés et de onze (11) entreprises qui emploient des diplômés de l’IBAM. Les résultats obtenus montrent que le niveau d’instruction, l’expérience, les compétences, les stages et la spécialité de formation sont les facteurs qui influencent l’insertion professionnelle des diplômés ; et que les employeurs ont une bonne perception sur leurs compétences professionnelles. Des suggestions, aussi bien des étudiants que des employeurs sont faites pour améliorer la qualité de la formation.

L’objectif de cette recherche est d’analyser la relation entre la dette extérieure et la vulnérabilité économique en considérant le rôle des ressources naturelles et de la qualité des institutions en Afrique subsaharienne. Nous utilisons un modèle de panel dynamique de 41 pays, estimé par la méthode des GMM en système sur la période 2000 à 2018. Les résultats suggèrent qu’une plus grande vulnérabilité économique tend à entraîner une augmentation de la dette extérieure. La qualité des institutions peut amoindrir le recours à la dette extérieure. Pour les pays disposant de fortes rentes de ressources naturelles, une meilleure qualité des institutions peut ne pas creuser la dette mais seulement jusqu’à un certain seuil de vulnérabilité économique.

Theories of contraception and fertility are currently dominated by economic and cultural arguments. A demographic perspective can usefully expand these theories through “addition,” “explication,” and “reconciliation.” The addition is about drawing attention to salient demographic forces that have previously been underconsidered whether these forces operate at the macro, meso, or microlevels. Explication is about adding explanatory flesh to proximate economic or cultural influences, which can themselves result from more fundamental demographic changes. Finally, reconciliation is about moving beyond an “economy -OR- culture” binary to seek complementarities and synergies. Decomposition methods inspired by a demographic perspective help such reconciliation. They offer handy empirical tools for assessing how economic, cultural, and demographic forces jointly shape changes in national rates of contraception, and how their contributions may change over time. Thus, demographic perspectives are not offered as a substitute but as an avenue to integrate cultural, economic, and demographic perspectives and to foster richer contextual analysis.

The widespread use of herbal preparations during childbirth and postnatal care in some developing countries is generating interest in scientific research about their standardized use. This study aims to compare the phytochemical profiles, the antioxidant properties, and the contractile effects of plants used to manage the childbirth of seven samples of plants (bark of Acacia senegal (L.) Willd, leaves and bark of Sclerocarya birrea, leaves of Lawsonia inermis L, whole plant of Sesamum alatum, whole plant of Ceratotheca sesamoides Endl. and brak of Ficus platyphylla). Qualitative and quantitative phytochemical screening was carried out using HPTLC and colorimetric methods. Antioxidant activity was evaluated using DPPH, ABTS and FRAP methods. Enzyme inhibition was performed on lipid peroxidation (LPO) and 15-Lipoxygenase (15-LOX). The contractile effect of uterine smooth muscle in NMRI mice was assessed ex vivo. The screening revealed the presence of several phytoconstituents, such as tannins, flavonoids, coumarins, saponins, sterols, and triterpenes. The highest content of phenolic compounds and tannins, respectively 980.61 ± 0.60 and 764.80 ± 0.54 µg GAE/mg dE, were obtained with the ethanolic extract of bark of Sclerocarya birrea (eth-Dn-e). The highest content of flavonoids (456.95 ± 0.89 µg QE/mg dE) was obtained with the ethanolic extract of Ceratotheca sesamoides (eth-Y). The ethanolic extract of Ficus platyphylla bark (eth-G) effectively reduced DPPH, with an IC50 of 1.46 ± 0.06 µg/mL. The highest ferric ion-reducing power was obtained with Sclerocarya birrea bark decoction (Da-Dn-e), (78.95 ± 5.74 mmol AAE/g). Ethanolic macerate of Acacia senegal bark (eth-D) showed the lowest IC50 against 15-LOX at 32.18 µg/mL. The aqueous macerate of Ceratotheca sesamoides (Ma-Y) gave the highest percentage inhibition of LPO, at 62.07 ± 0.01 %. The highest uterine contraction at 10 mg/mL was 1.38 [A(cm)/uterus(cm)], obtained with ethanolic maceration of the whole plant of Ceratotheca sesamoides Endl. (eth-Y). The traditional use of plants during childbirth could be linked to the antioxidant and/or uterotonic effects of phytoconstituents. These constitutes a scientific basis that could justify the use of these plants in the management of childbirth.

This article examines the repercussions of growing insecurity, particularly linked to terrorism, on mobility and development in Burkina Faso. The aim is to examine the impact of this insecurity on internal travel and to highlight potential levers for strengthening the resilience of transport systems in the face of current security challenges. An analysis based on a literature review reveals that insecurity has profoundly disrupted mobility, hampering trade and restricting access to essential services, particularly in rural areas. However, community initiatives and the establishment of secure corridors have been put in place to mitigate these negative impacts. Although these efforts have led to a partial improvement in mobility and a limited recovery of the economy, it is imperative that the government, in partnership with the international community, step up its actions in terms of security and strengthen transport infrastructures. At the same time, support for resilience programmes targeting vulnerable populations must be a priority in order to provide a sustainable response to the challenges posed by this persistent insecurity.

This paper presents an analysis of three vegetable oil droplets vaporization process in the range temperature from 473 to 723 K corresponding to low temperature conditions found in diesel engine cold parts. This process is analyzed for a droplet evaporating in a hot environment at atmospheric pressure using the fiber-suspended droplet technique well used in the literature, and analyzing the droplet normalized square diameter and temperature evolution surrounding the droplet when vaporizing. The main difference between those already studied in literature is the range temperature which varies between 473 and 723 K in which vegetable oils vaporizing problems leading to deposits formation in the cold regions of diesel engines especially in direct injection. This presents a scientific challenge for resolving deposit formation. The findings reveal that vegetable oil droplets experience expansion and heating for temperatures below 623 K: no other changes are observed. Between temperatures of 623 and 683 K, an increase in temperature, expansion, and an inconsistent vaporization is observed. This is followed by a phase of low and constant vaporization. From 683 K, vegetable oils experience an initial stage of heating and expansion, which is accompanied by a phenomenon of puffing and bursting. Finally, in the last phase, residue formation occurs. Puffing and bursting phenomena manifest once the temperature reaches 683 K, indicating the emergence of substantial quantities of light compounds including carboxylic acids, aromatics, acrolein, ketene, and fatty acids. These compounds are formed through the thermal degradation and polymerization of vegetable oils. This process causes deposits to form in the colder areas of diesel engines

The basement aquifers in Burkina Faso are increasingly exposed to groundwater pollution, largely due to socio-economic activities and climatic fluctuations, particularly the reduction in rainfall. This pollution makes the management and understanding of these aquifers particularly complex. To elucidate the processes controlling this contamination, a methodological approach combining principal component analysis (PCA) and multivariate statistical techniques was adopted. The study analyzed sixteen physicochemical parameters from 58 water samples. The primary objective of this research is to assess groundwater quality and deepen the understanding of the key factors influencing the spatial variation of their chemical composition. The results obtained will contribute to better planning of preservation and sustainable management measures for water resources in Burkina Faso. The results show that three principal components explain 72% of the variance, identifying anthropogenic inputs, with two components affected by mineralization and one by pollution. The study reveals that the groundwater is aggressive and highly corrosive, with calcite saturation. Water-rock interactions appear to be the main mechanisms controlling the hydrochemistry of groundwater, with increasing concentrations of cations and anions as the water travels through percolation pathways. PCA also revealed that the residence time of the water and leaching due to human activities significantly influence water quality, primarily through mineralization processes. These results suggest that rock weathering, coupled with reduced rainfall, constitutes a major vulnerability for aquifer recharge.

Introduction: This study was carried out to assess the quality of sheep meat sold to consumers in Saaba municipality. Methods: A preliminary survey consisted of assessing hygiene and sampling meat in butchers’ stores. To achieve this, 100 sales outlets were surveyed for their hygiene conditions. 25 mutton meat samples were sampled in the three villages in Saaba district and analyzed using conventional microbiological techniques. The analysis consisted of determining the microbiological characteristics. Results: According to the results of this study, 100% of the butchers surveyed were men of the region. Among these men, 13% had secondary education, 46% had primary education and 41% were illiterate. Of the 100 retail outlets visited, 96% of the sellers were unaware of the hygiene rules and the dangers of microorganisms. The microbiological analysis of the samples revealed that 100% of the meat was of unsatisfactory microbiological quality. The average contamination rate by total aerobic mesophilic flora, total coliforms, Staphylococcus aureus and yeasts and molds was 8.93 × 106, 3.12 × 105, 3.69 × 106, and 6.74 × 103 CFU/g respectively. No Salmonella strain was detected in any of the samples analyzed. Conclusion: Our results pointed out the unsatisfactory safety quality of the sheep meat sold in the sheep meat and good hygiene practices.

Research in Anglophone literature and psychology often involves studying the internal attributes of authors, characters, and even readers for a better understanding of works. Researchers from the departments of Anglophone studies and psychology at UJKZ follow this method, often applying psychological theories to their studies. Surprisingly, researchers from both departments do not fully utilize the benefits of interdisciplinarity, despite its contribution to more conclusive results. This article aims at promoting interdisciplinarity between Anglophone literature and psychology at UJKZ by examining existing scientific collaborations, identifying their challenges, and proposing solutions for better interdisciplinary collaboration. A quantitative method approach is used, drawing on William H. Newell’s (2001) theory of interdisciplinarity. Lack of communication is identified as the main obstacle to interdisciplinarity among these researchers, emphasizing the need for improving communication to reach more effective scientific collaboration. Keywords: Anglophone, interdisciplinarity, literature, psychology, research.