Clautaire Mwebi Ekengoue - Academia.edu (original) (raw)

Papers by Clautaire Mwebi Ekengoue

HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific re... more HAL is a multidisciplinary open access archive for the deposit and dissemination of scientific research documents, whether they are published or not. The documents may come from teaching and research institutions in France or abroad, or from public or private research centers. L'archive ouverte pluridisciplinaire HAL, est destinée au dépôt et à la diffusion de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

Introduction: In Cameroon, the numbers of births as well as that of maternal mortalities are cons... more Introduction: In Cameroon, the numbers of births as well as that of maternal mortalities are constantly changing, as a result of high fertility and low use of modern contraception (MC). Purpose of research: The study aims to identify the obstacles to MC use in Penka-Michel Health District. Results: 331 women, 112 men and 42 health workers were surveyed. Modern contraceptive prevalence among women was about 24%. The major barriers they perceived included lack of information, desire to conceive, fear of side effects, misunderstanding of breastfeeding, and spousal opposition. For men, these barriers included the desire to have many children, fear of side effects, and infidelity of the woman. There are also some socio-cultural and religious parameters, inadequate provision of care in family planning, poor delivery of available resources and lack of financial resources. Age (OR=3.4; P=0.03), educational attainment (OR=2.4; P=0.006) and spouse (OR=5.6; P<0.0001) had a statistically significant influence on the use of MC by women. In men, the influence is marked by age (OR=3; P=0.02) and marital status (OR=11; P<0.0001). Conclusions: The increase in contraceptive prevalence is possible only through awareness and training on the indicated methods as well as the financial support of the spouse to optimize the use of MC in Penka-Michel Health District.

Indian Journal of Physics/Indian journal of physics/Indian Journal of Physics and Proceedings of the Indian Association for the Cultivation of Science, Apr 29, 2024

Physica Scripta, 2021

This paper gives a detailed description of a high-performance polariton condensate for a quantum ... more This paper gives a detailed description of a high-performance polariton condensate for a quantum mechanical two-level system (TLS). We propose a transition metal dichalcogenides (TMDs) setup and theoretically carry out the spectroscopy of these polariton condensates. Through theoretical and numerical analysis, we obtain many features in two dimensional (2D) multilayer TMDs. We compute the energy of the system and the Landau-Zener-Stückelberg (LZS) quantum tunneling probability under the effect of a sequence of laser light. At certain critical 2D TMDs parameters, the system exhibits a multi-crossing scenario in a privileged position of 2D multilayer TMDs. We predict the consecutive modulations and highlight the conservation of the LZS interference patterns mapped from the 2D TMDs system. At weak coupling regime, a successful conversion of interferometry signals is identified for some values of laser frequency. We explain such a result as a valley sensitive cavity rate model due to co...

European Scientific Journal, ESJ, 2021

The involvement of pesticides in agriculture requires the implementation of best phytosanitary pr... more The involvement of pesticides in agriculture requires the implementation of best phytosanitary practices in order to guarantee the health of populations and preserve the environment. This study focused on the assessment of phytosanitary practices of tomato producers in Foumbot,

The European Physical Journal Plus, 2020

We have investigated the dynamic of cooled and trapped polariton state using Landau–Zener–Stuckel... more We have investigated the dynamic of cooled and trapped polariton state using Landau–Zener–Stuckelberg interferometry theory (LZSIT). The effects of exciton–cavity coupling and the laser cooling over the qubit dynamics are analyzed in multi-crossing scenarios, supporting some of our basic results (Kenfack et al. in Comput Condens Matter 11:47–54, 2017; Ekengoue et al. in Comput Condens Matter 14:106–113, 2018). We have performed detailed calculations of the energy eigenvalues, non-adiabatic and adiabatic transition probabilities in the framework of weak- and strong-coupling regime under the laser light. As a main result, we pointed out the braking down of the Pauli exclusion principle providing the applicability of LZSIT for the analysis of polariton’s dynamic through a model which satisfies Fermi–Dirac statistics. Moreover, we found the generation of arbitrary waveforms of interferometric signals including sinusoidal, for weak coupling and strong laser amplitude. Thus, the dynamics of the polariton induces the destruction and the construction of interferences patterns in strong coupling between cavity laser and qubit. Extremely accurate interferometric signals generation by means of geometric phase effect has been demonstrated in this work with the goal of realizing robust control of the quantum coherent states of the polaritonic system. This geometric phase enhancement, which is essentially originated from the dynamic behavior of cooled and trapped polariton, is a significant consequence of the fastest population transfer and quantized energy of the system. Therefore, the geometric phase plays a crucial role in the study of the alter crossings behavior through cooled and trapped polariton, especially in the population transfer and energy of the system.

Computational Condensed Matter, 2018

An interaction between matter and light remains the most important physical mechanism which open ... more An interaction between matter and light remains the most important physical mechanism which open path to explore the fundamental principles of quantum mechanics. In this paper, the dynamical behavior of the system of cooled and trapped polariton is studied. In particular, we analytically and numerically studied decoherence in a system of cooled polariton under the influence of a magnetic trap by evaluating physical parameters such as force and its corresponding torque, transition probability of founding the system in the excited state and energy. It's shown that an introduction of magnetic field in the system as a trap increases considerably the total energy of the system. In the same manner, we investigated the total entropy of the system and evaluated its entanglement. We showed that, the system reaches asymptotic values of entanglement of 0.37 after some fluctuations, meaning that the magnetic field reduces considerably decoherence in the system.

Computational Condensed Matter, 2017

An interaction between electrons with photon is an important phenomenon in physics and, particula... more An interaction between electrons with photon is an important phenomenon in physics and, particularly, condensed matter and theoretical physics. The result of this interaction yields a quasi-particle called, polariton. In this study we investigated the role of polariton in cooling and trapping processes. We observed that the probability of finding cooled and trapped polariton in the excited state is controlled by the environment. Similar results are observed for other physical parameters. It is shown that the environment plays an important role in laser cooling and trapping of electrons.

Physics Letters A, 2020

We study the dynamic of magneto-polaron condensate in monolayer two dimensional (2D) transition m... more We study the dynamic of magneto-polaron condensate in monolayer two dimensional (2D) transition metal dichalcogenides (TMDs) materials of 2H types in triangular quantum well potential. Within both the quantum mechanical Schrödinger approach (QMSA) and the improved Wigner-Brillouin theory (IWBT), Landau energies levels (LELs) are derived. We have shown that the magneto-polaron condensation is enhanced in monolayer MoSe 2 compared to MoS 2 , WS 2 and WSe 2. We derive various levels by increasing a magnetic field and laser parameter. We show that the quantum confinement lifts the degeneracy of the Landau levels (LLs) resulting in an anticrossing and crossing. The dephasing effect due to the quantum well potential's parameter plays an important role in the magneto-polaron energy corrections, which are also affected by the amplitude of the laser field. The system presents Stückelberg oscillations which is important for practical applications.

International Journal of Innovation and Applied Studies, Dec 5, 2020

Environnement, Ingénierie & Développement, 2021

This paper presents the impacts of Nkol’Ossananga sand harvesting on social live and local econom... more This paper presents the impacts of Nkol’Ossananga sand harvesting on social live and local economy based on field investigations and data analysis. Laboratory analysis of sand samples from the site has shown that the cleanliness of the Nkol’Ossananga sand nears 100%. This means that Nkol’Ossananga sand is pure and clean, most appropriate for house constructions and building engineering. The activity produces incomes to all actors of the chain value and government. Incomes generated are used by artisans to build their houses, buy some electronic devices, and take care of their families or to capitalize in their business investigation. In spite of the positive impacts presumed, Nkol’Ossananga sand harvesting also stands as the origin of many negative impacts including cultural brewing, delinquency, precocious abandon of studies and abandon of agriculture. The exploitation is done with rudimentary tools and poor technics thereby exposing artisans to several risks and illnesses. For sus...

European Scientific Journal ESJ

Le but de la présente étude est de formuler et fabriquer des suppositoires à visée antipaludique ... more Le but de la présente étude est de formuler et fabriquer des suppositoires à visée antipaludique à base de matières premières locales afin d’améliorer la prise en charge du paludisme, essentiellement chez les enfants âgés de moins de 5 ans. Pour faire cela, on a utilisé comme principe actif la poudre de feuilles et tiges sèches de Artémisia annua provenant de la Région de l’Ouest-Cameroun et comme excipient le beurre de karité en provenance de la région du Nord Cameroun puis amélioré à 4% de silice colloïdale. Les essais organoleptiques ont mis en évidence une poudre de couleur grisâtre, de saveur amère et très odorante. L’analyse granulométrique a montré que la poudre de feuilles et tiges sèches de Artémisia annua a une granulométrie allant de très fine à fineLa concentration en flavonoïdes totaux de la poudre de feuilles et tiges sèches de Artémisia annua est de 76,9 μg/ml d’équivalent de quercétine. Les suppositoires à visée antipaludique fabriqués à partir de 250mg de poudre de ...

International Journal of Innovation and Applied Studies, Feb 2, 2021

Gestion des constructions des bâtiments pour habitation au Cameroun: Historique, état des lieux e... more Gestion des constructions des bâtiments pour habitation au Cameroun: Historique, état des lieux et perspectives d'une réappropriation des techniques de construction durables (ancestrales) [ Construction management of house buildings in Cameroon: History, overview and perspectives for a reappropriation of sustainable construction techniques (ancestral) ]

Cleaner Engineering and Technology

Abstract This paper focuses on assessing and development of water purification system for address... more Abstract This paper focuses on assessing and development of water purification system for addressing water quality effects associated with sand mining in Toutsang locality, West-Cameroon. The study approach involved field investigations, laboratory analysis and design of waste water treatment system. Water samples were randomly collected from the study into well-labelled containers and conveyed to Unite de Recherche d’Analyse des Sols et Chimie de l’Environnement, Faculte d’Agronomie et des Sciences Agricoles (FASA) at the University of Dschang for analysis. Results from the physico-chemical analysis show elevated levels of total suspended solids (TSS), magnesium (Mg), turbidity and iron (Fe) in water samples collected downstream of the River close to the mining site, which exceeds the World Health Organization (WHO) standards. Based on the results of the physico-chemical analysis, a waste water treatment comprising of sedimentation tanks is proposed to treat waste water from the sand mining site. The designed water treatment system can be used to treat contaminated water from sand mining sites for domestic use. The proposed model tank needs to be implemented to restore Toutsang Water quality for indoor purpose and household use.

European Scientific Journal, ESJ, 2018

Sand is classified among the low value development minerals, even though it is massively used in ... more Sand is classified among the low value development minerals, even though it is massively used in the world. The exploitation of that construction mineral at Nkol’Ossananga, around Yaounde, is done by craftsmen in unsafe conditions, such as: the exposure to a wide range of diseases and the destruction of the environment. We carried out a study on occupational health and safety and environmental impacts on the Nkol’ossananga site. Our method consisted firstly of the bibliographic review, sandpit quarry investigations afterwards, and lastly the data analysis. Tabulation of results showed that the population in the site is essentially threatened by diseases such as dysentery (15%), fibromyalgia (25%), typhoid fever (55%), otalgia (10%), ocular pains (15%), and malaria (45%). Craftmen work without any personal protective equipment (PPE) and are often victims of drowning and bacterial infections. The high demand of sand in Yaounde involves the development of the activity in other sites an...

Keywords: Sand mining Toutsang locality Toutsang water quality Physico-chemical analysis Sediment... more Keywords: Sand mining Toutsang locality Toutsang water quality Physico-chemical analysis Sedimentation tank Indoor purpose and household use A B S T R A C T This paper focuses on assessing and development of water purification system for addressing water quality effects associated with sand mining in Toutsang locality, West-Cameroon. The study approach involved field investigations , laboratory analysis and design of waste water treatment system. Water samples were randomly collected from the study into well-labeled containers and conveyed to Unit e de Recherche d'Analyse des Sols et Chimie de l'Environnement, Facult e d'Agronomie et des Sciences Agricoles (FASA) at the University of Dschang for analysis. Results from the physico-chemical analysis show elevated levels of total suspended solids (TSS), magnesium (Mg), turbidity and iron (Fe) in water samples collected downstream of the River close to the mining site, which exceeds the World Health Organization (WHO) standards. Based on the results of the physico-chemical analysis, a waste water treatment comprising of sedimentation tanks is proposed to treat waste water from the sand mining site. The designed water treatment system can be used to treat contaminated water from sand mining sites for domestic use. The proposed model tank needs to be implemented to restore Toutsang Water quality for indoor purpose and household use.