Usages des plantes à effet pesticide au Cameroun. Poster communications – P47

Les pesticides d'origine végétale constituent une des alternatives à la lutte chimique avec des produits de synthèse et un moyen complémentaire aux autres méthodes de lutte. Dans le cadre du projet Knomana (Knowledge management), portant sur la gestion des connaissances et la conservation des données relatives aux plantes pesticides en Afrique (http://urlz.fr/6P4a), un état des lieux des usages expérimentaux (laboratoire et champs) et des utilisations par les producteurs a été réalisé. La recherche des articles publiés, leurs saisies pour alimenter une base de connaissances et l'analyse préliminaire effectuée ont permis de recenser 48 espèces végétales utilisées au Cameroun pour protéger 14 espèces végétales : Apium graveolens, Citrus sinensis, Monodora myristica, Oryza sativa, Phaseolus vulgaris, Pisum sativum, Solanum lycopersicum, Sorghum bicolor, Triticum sp., Vigna mungo, Vigna radiata, Vigna subterranea, Vigna unguiculata, Zea mays. Les travaux ont notamment concerné la composition chimique des extraits de plantes, leurs propriétés insecticide et antimicrobienne. Les usages relevés concernent la protection des semences contre des maladies telles que la pourriture des racines et des épis du maïs causé par le champignon Fusarium verticiloïdes, la maladie des taches brunes du riz (due au pathogène Bipolaris oryza) et le flétrissement de la tomate (Ralstonia solanacearum). Les connaissances enregistrées relevant de la protection contre les insectes des cultures concernent essentiellement ceux des denrées stockées comme Sitophilus zeamais ou Callosobruchus maculatus et d'autres espèces du genre Sitophilus. À ce stade de la collecte des informations les usages en protection foliaire semblent donc faibles dans ce pays. Les résultats obtenus indiquent clairement qu'il existe plusieurs plantes à effet pesticide dans la flore végétale du Cameroun. En dehors du neem (Azadirachta indica) déjà bien connu en Afrique, des espèces apparaissent intéressantes à exploiter de façon extemporanée par les agriculteurs ou à développer de façon commerciale à l'exemple de Ocimum gratissimum, Callistemon citrinus, Cymbopogon citratus, Ageratum conyzoides, Tephrosia vogelii, Bidens pilosa, Commelina benghalensis, Emilia coccinea, Erigeron floribundus, Eucalyptus tereticornis, Euphorbia hirta, Oxalis barrelieri, Podocarpus milanjianus. Dans certains cas, l'adoption nécessitera des études complémentaires sur les risques de toxicité vis-à-vis des organismes non cibles (dont l'homme) et de l'environnement

Atg11 and Atg9 interaction in selective autophagy

Selective autophagy, induced by cellular stresses, degrades/recycles a specific cargo. Ithelps prevent diseases like Parkinson’s, Huntington\u27s, cancer, and bacterial infections. It involves the formation of an autophagosome, a double-membrane vesicle that takes the cargo to the vacuole/lysosome for degradation. Atg11, the central organizer of selective autophagy, acts as a scaffold protein, interacting with Atg9, Atg1 and other Atg proteins. Our research focuses on finding mutations in Atg11 that specifically disrupt its interaction with Atg9 without affecting its dimerization or interaction with Atg1. We targeted residues 455-535 of Atg11 as a putative Atg9 interaction site, performing mutagenesis on four key residues in this region. The quadruple mutant (Y468A, D516A, L517A, L526A) disrupted Atg11 and Atg9 interaction. However, Y468A, L526A did not, while D516A, L517A showed only partial disruption. We aim to further investigate other potential residues within this region that may be crucial for Atg11 and Atg9 interaction

Using a Policy of "Gross National Happiness" to Guide the Development of Sustainable Early Learning Programs in the Kingdom of Bhutan: Aspirations and Challenges

A national study on demand for early childhood care and development programs in Bhutan found strong support for development of a new early childhood care and development (ECCD) sector.  A wide range of stakeholders participating in the study, including ministries of education and health, post-secondary institutions, private preschool providers, community management committees, parents and children, emphasized the goal of preschool to promote success in English-medium formal education.  Promoting cultural traditions was also a priority, while developing children’s proficiency in home languages was hardly mentioned. The study highlighted the changing needs of Bhutanese families in the current context of increasing urbanization, dual career parents, and a shift from extended to nuclear family homes. Recommendations derived from the study encouraged a made in Bhutan approach to ECCD policy, programs, and professional education.  Subsequent to the study, the national education policy included plans for implementation of ECCD covering children from birth to 8 years old. To ensure the sustainability and cultural congruence of new programs and investments with the Kingdom’s Gross National Happiness Policy, a Gross National Happiness Commission screened and approved the new National Education Policy, which the Ministry of Education is charged with implementing. The emergence of an ECCD sector in Bhutan points to the role that national aspirations and value-driven policies and review processes could play in maintaining language diversity and transmitting culturally based knowledge

Design of Radiation Tolerant Materials Via Interface Engineering

A novel interface engineering strategy is proposed to simultaneously achieve superior irradiation tolerance, high strength, and high thermal stability in bulk nanolayered composites of a model face-centered-cubic (Cu)/body-centered-cubic (Nb) system. By synthesizing bulk nanolayered Cu-Nb composites containing interfaces with controlled sink efficiencies, a novel material is designed in which nearly all irradiation-induced defects are annihilated.United States. Dept. of Energy. Office of Basic Energy Sciences (Energy Frontiers Research Center. Award 2008LANL1026

Improvement of Cracking Resistance for the Semi-Rigid Base Layer Reinforced by Geogrid

Reinforcement using an interlayer system appears nowadays as one of the techniques which is commonly used in asphalt pavement construction to improve its performances, extend its projected service life and reduce its structural cross section. Among a large number of existing interlayer systems, the geogrid has shown an effective use in pavement reinforcement with hot mix asphalt overlay. This article aims to research the mechanism leading to the spread of reflective crack and the anti-cracking effect of geogrid in semi-rigid pavement. The 3D finite element modeling package (ANSYS) has been used as tool to analyze the mechanical response of pavement model unreinforced and reinforced with different numbers of geogrid placed at different positions in the base layer under the influence of axle load. The results obtained from the finite element analysis have shown that, the use of geogrid in the semi-rigid base aids to reduce the stresses and strains both at the bottom of asphalt and base layer. Keywords: Reinforcement, Asphalt pavement, geogrid, Reflective crack, Anti-cracking effect

Evaluation of anti-inflammatory activity of Oxalis corniculata in experimentally induced inflammatory bowel disease in rats

Background: Oxalis corniculata is traditionally well-known for its versatile uses. The present study was carried out to evaluate the anti-inflammatory activity of the ethanolic extract of O. corniculata (EEOC) leaves in experimentally induced inflammatory bowel disease in rats.Methods: Rats were treated with the extract for 7 days following which acetic acid was used to induce colitis. Animals were euthanized, 24 hrs after induction of colitis and colon was removed and assessed for macroscopic injury, as well as also processed for histopathological examination. Sulfasalazine 360 mg/kg was used as the standard drug. The extract was used in 200 mg/kg, 300 mg/kg and 400 mg/kg doses.Results: At all the three doses, the EEOC showed significant (p<0.01) anti-inflammatory activity in experimental models.Conclusion: Results obtained in this study substantiate the anti-inflammatory effect of EEOCleaves

Evaluation of the anti-nociceptive potential of ethanolic extract of leaves of Bryophyllum pinnatum in experimental animals

Background: The plant Bryophyllum pinnatum is traditionally used for the treatment of pain and inflammation. The present study was carried out to evaluate the antinociceptive effect of the ethanolic extract of the leaves of B. pinnatum (EEBP) using a hot plate method and acetic acid induced writhing test in mice.Methods: In the hot plate analgesiometer method, the time between the placement on the hot plate and the occurrence of licking of the paws, shaking or jumping off from the plate was recorded as response latency. Total numbers of stretching episodes for 30 mins immediately after acetic acid injection in all the groups were recorded in acetic acid induced writhing method. Pentazocine (10 mg/kg intraperitoneal) and aspirin (500 mg/kg) were used as the standard drugs in the hot plate and acetic acid induced writhing method, respectively. Extract was used in 200, 300 and 400 mg/kg doses.Results: At all the three doses the EEBP showed significant (p<0.01) anti-nociceptive activity in experimental models of Eddy’s hot plate analgesiometer and acetic acid induced writhing method in mice.Conclusion: The observed pharmacological activities provide the scientific basis to support traditional claims, as well as exploring some new and promising leads in the management of pain

Evaluation of antidiabetic activity of Oxalis corniculata in streptozotocin induced diabetic rats

Background: Oxalis corniculata is traditionally well known for its versatile uses. The present study was carried out to evaluate the antidiabetic action of ethanolic extract of Oxalis corniculata in streptozotocin induced diabetic albino rats.Methods: To look for the antidiabetic effect the albino rats were divided into 5 groups, each consisting of 6 animals. Diabetes was induced by a single i.p. injection of streptozotocin at a dose of 50mg/kg body weight. Standard drug, glibenclamide and ethanolic extract of Oxalis corniculata (EEOC) at doses 200mg/kg and 400mg/kg body weight was fed to the rats and it was continued till the end of the study. The blood glucose levels were estimated on day 0, 3, 7, 14 and 21 day. The standard drug and the extract were fed from day 4 onwards.Results: The antidiabetic property of the extract has shown increasing trend with   increase in dose and there was a gradual decrease in blood glucose levels with increased period of exposure to the test drug.Conclusions: Results obtained in this study substantiate the anti-diabetic activity of EEOC leaves

Epilepsie tardive avec abus de marijuana: corrélation clinico-radiologique (à propos d’un cas)

Background: Marijuana is the most widely used illicit substance in the world. The relation between marijuana use and epileptic seizures is still controversial. Authors report a case of late onset epilepsy with marijuana abuse and brain magnetic resonance imaging (MRI) findings. Observation: A 44-year-old patient was admitted for 03 isolated episodes of secondary generalized tonic-clonic seizures. He had a history of 26 years regular marijuana smoking. On admission, we found a tachycardia, psychomotor slowing, asymmetric hyperreflexia, bilateral Babinski sign without weakness. Laboratory work-up showed a high level of urine of-9-tétrahydroxycannabinol. Electroencephalogram was normal. Brain MRI revealed abnormal signal intensities in the right frontal lobe and basal ganglia. Seizures cessation was obtained with antiepileptic treatment. Conclusion: The relationship between marijuana abuse and epilepsy remains unclear. Marijuana abuse could lead indirectly to epilepsy through epileptogenic focal brain lesion(s) or play as a trigger factor for pre-existing epileptic seizures.Introduction : La marijuana est la drogue la plus consommée dans le monde. La relation entre la consommation de cette substance et l’épilepsie reste controversée. Les auteurs rapportent un cas d’épilepsie tardive avec abus de marijuana. Observation : Le patient âgé de 44 ans était admis pour trois épisodes isolés de crise focale tonicoclonique secondairement généralisée avec une notion de consommation régulière de marijuana depuis 26 ans. A l’admission, l’examen retrouvait une tachycardie, un ralentissement psychomoteur, une hyperréflexie bilatérale asymétrique, un signe de Babinski bilatéral, mais sans déficit moteur. Les examens biologiques avaient montré un taux élevé de Δ-9-tétrahydroxycannabinol urinaire. L’électroencéphalogramme était normal et l’IRM cérébrale montrait des anomalies de signal dans le lobe frontal droit et les ganglions de la base. L’arrêt des crises était obtenu sous traitement antiépileptique. Conclusion : L’abus de marijuana pourrait favoriser les crises épileptiques soit indirectement en provocant des lésions cérébrales focales épileptogènes, soit en agissant comme facteur déclenchant de crises épileptiques préexistantes

Factors Affecting Online Teaching and Learning Amidst Covid-19 in College of Science and Technology

COVID-19 had an enormous influence on students, teachers, and educational institutions all over the world, as it did on so many other aspects of everyday life. Schools and colleges were closed across the world to comply with social distancing initiatives. In order to ensure education continuity, the traditional mode of face-to-face learning has been replaced by online learning. This paper sets out to determine the factors affecting online teaching and learning amidst COVID-19 in College of Science and Technology. The research is based on a mixed methodology consisting both qualitative &amp; quantitative approach which is used mainly to gain more in-depth understanding of the factors that affect online teaching and learning for both tutors and students. Firstly, the quantitative approach is applied whereby an online survey will be carried out in order to see the   core factors in the bigger picture. The survey was conducted via Google form for the students and collected the data from 297 respondents. It was then followed by the qualitative approach whereby four teachers and nine students were interviewed (semi-structured interview) to validate the findings collected from the survey and consequently find the recurring factors. Then, to get a true integration of data and the relations between the qualitative and quantitative aspects of the data sets, the Dedoose software is used to analyze as a whole rather than two different components that must be pieced together. It was found that network connectivity, equipment availability for practical classes, nature of student and tutors, data insufficiency, favorable environment, module content and how adaptive student and tutor were to online platform were the factors identified affecting online teaching and learning at CST during Covid-19. Keywords:Online teaching and learning, Factors, Equipment availability, Network connectivity, Student characteristics, Tutors characteristics, Data insufficiency, Favorable environment, Module content DOI: 10.7176/JEP/13-20-03 Publication date:July 31st 202