Conservation et étude de la valeur nutritive des larves de Rhynchophorus phoenicis (Curculionidae) et Oryctes rhinoceros (Scarabeidae), deux coléoptères d’intérêt alimentaire au Congo-Brazzaville

Des larves appartenant à deux espèces de coléoptères, Rhynchophorus phoenicis (Curculionidae) et Oryctes rhinoceros (Scarabeidae), prélevées dans les marchés et dans des palmiers de forêts galeries ont étéramenées au laboratoire puis élevées séparément dans les conditions ambiantes. Des coeurs de palmiers appartenant à Elaeis guinensis et Raphia sp ont été placés tous les cinq jours dans les conditions d’élevage (à 26,20 °C et 72,71% HR% en moyenne) afin de stimuler la croissance larvaire. Leur conservation a été réalisée jusqu’à l’émergence des imagos. Les résultats obtenus montrent que les larves de stade II de R.phoenicis atteignent le stade nymphal à partir du 40ème jour et restent à ce stade pendant 60 jours, à l’issu desquels le premier adulte est obtenu. Par contre, les larves de O. rhinoceros conservées, n’atteignent le stadenymphal qu’après 50 jours d’élevage. Les premières émergences d’imagos sont observées à partir du 94ème jour. L’extraction des lipides à l’hexane avec la méthode de Soxhlet indique que les larves de R. phoenicis ontdes taux plus élevés d’acides gras que celles de O. rhinoceros, tandis que les taux de protéines sont plus élevés chez O. rhinoceros. Les éléments minéraux comme le sodium, le magnésium, le fer et le calcium montrent des valeurs plus élevés chez R. phoenicis

Fragmentation d’un écosystème Littoral : cas de la baie de Loango au Congo-Brazzaville

L’action de l’homme sur la modification profonde et dans certains cas irréversibles de son milieu est étudiée dans une partie de la baie de Loango, à Matombi au Nord de Pointe-Noire. Nous avons par des étudespréliminaires, recensé différentes perturbations de cet écosystème littoral et analysé les pressions écologiques exercées par la modification des biotopes voisins. Les observations se sont déroulées du 07 au 21 septembre en 2007, et en 2008 du 13 juin au 10 août puis du 27 octobre au 09 décembre de la même année, à une fréquence d’une visite tous les deux jours, soit quatre visites par semaine et seize visites par mois. Les précipitations, l’abattage des arbres et des arbustes, l’élimination abusive de la strate herbacée à des fins touristiques et l’érosion marine sur le continent sont les principaux facteurs concourant à la perturbation du littoral de Matombi. Ce processus se traduit par une modification de la répartition des espèces animales et végétales, des habitats et microhabitats et stimule les possibilités adaptatives des espèces animales Invertébrés (comme les crustacés, certains hyménoptères, des Isoptères) mais aussi des Vertébrés (Oiseaux et certains petits mammifères).Mots clés: Dégradation, écosystèmes côtiers, Habitats, Biodiversité, tropica

What do students know and understand about the Holocaust? Evidence from English secondary schools

This research report has been written under the auspices of the University College London (UCL) Centre for Holocaust Education. The Centre is part of the UCL Institute of Education – currently the world’s leading university for education – and is comprised of a team of researchers and educators from a variety of different disciplinary fields. The Centre works in partnership with the Pears Foundation who, together with the Department for Education, have co-funded its operation since it was first established in 2008. A centrally important principle of all activity based at the UCL Centre for Holocaust Education is that, wherever possible, classroom practice should be informed by academic scholarship and relevant empirical research. In 2009, Centre staff published an extensive national study of secondary school teachers’ experience of and attitudes towards teaching about the Holocaust (Pettigrew et al. 2009). This new report builds on that earlier work by critically examining English school students’ knowledge and understanding of this history. In both cases, research findings have been – and will continue to be – used to develop an innovative and ground-breaking programme of continuing professional development (CPD) for teachers and educational resources that are uniquely responsive to clearly identified classroom needs. The UCL Centre for Holocaust Education is the only institution of its kind, both within the United Kingdom and internationally, where pioneering empirical research is placed at the heart of work to support teachers and their students encountering this profoundly important yet complex and challenging subject in schools. The Centre offers a wide-ranging educational programme appropriate to teachers at all stages of their careers through a carefully constructed ‘pathway of professional development’. This provides opportunities for individuals to progressively deepen their knowledge and improve their practice. It offers a national programme of Initial Teacher Education in Holocaust education and a variety of in-depth and subject-specific CPD. In addition, the Centre also offers online distance learning facilities, including a fully accredited taught Masters-level module The Holocaust in the Curriculum. Through its Beacon School programme, Centre staff work intensively with up to 20 schools across England each year in order to recognise and further develop exemplary whole-school approaches and effective pedagogy. All of the courses and classroom materials developed by the UCL Centre for Holocaust Education are available free of charge to teachers working in England’s statefunded secondary schools. Further information can be found at www.ioe.ac.uk/holocaust

Larval ecology and infestation indices of two major arbovirus vectors, Aedes aegypti and Aedes albopictus (Diptera: Culicidae), in Brazzaville, the capital city of the Republic of the Congo.

BACKGROUND Invasive mosquito species, such as Aedes albopictus in Congo can affect the distribution of native species, changing the vector composition and pattern of disease transmission. Here, we comparatively establish the geographical distribution and larval habitat preference of Ae. aegypti and Ae. albopictus and the risk of arbovirus disease outbreaks using Stegomyia indices in the city of Brazzaville, the capital of the Republic of the Congo. METHODS Human dwelling surveys of water-holding containers for immature stages of Aedes was carried out in December 2017 in Brazzaville through a random cluster sampling method. A total of 268 human dwellings distributed in 9 boroughs and 27 neighbourhoods were surveyed across the city. RESULTS Overall, 455 potential larval habitats were surveyed. Both Ae. aegypti and Ae. albopictus were collected across the city with an overall high prevalence of Ae. aegypti (53.1%) compared to Ae. albopictus (46.9%). Geographical distribution analysis showed that Ae. aegypti was more abundant (mean = 6.6 ± 1.4) in neighbourhoods located in downtown, while the abundance of Ae. albopictus was low (mean = 3.5 ± 0.6) in suburbs. Peridomestic containers, especially discarded tanks, were the most strongly colonized productive larval habitat for both mosquito species with the prevalence of 56.4% and 53.1% for Ae. aegypti and Ae. albopictus, respectively. Globally, the house index (HI), Breteau index (BI) and container index (CI) were high for Ae. aegypti (26.6%, 38.4% and 22.6%) and Ae. albopictus (33.3%, 49.6% and 26.6%) compared to the transmission risk threshold (5%, 5% and 20%) established by the WHO/PAHO. Overall, pupae-based indices (the pupae index and the pupae per person index) were not significantly different between Ae. aegypti (273.4% and 23.2%) and Ae. albopictus (228.8% and 19.5%). CONCLUSIONS The findings of this study suggest a high risk for transmission of arbovirus diseases in Brazzaville and call for an urgent need to implement vector control strategies against these vectors in the Republic of the Congo

Geographical distribution of Aedes aegypti and Aedes albopictus (Diptera: Culicidae) and genetic diversity of invading population of Ae. albopictus in the Republic of the Congo [version 1; referees: 2 approved]

Background: The arbovirus vector, Aedes albopictus, originating from Asia, has recently invaded African countries, including the Republic of the Congo, where it was associated with a chikungunya outbreak. Up until now, little was known about its distribution in relation to the native Aedes aegypti and how the invasion will modify the epidemiology of arboviral diseases. Here, we assessed the current distribution of Ae. albopictus and Ae. aegypti in the Republic of the Congo and explored the genetic diversity of the invading species, Ae. albopictus. Methods: Immature stages of Aedes were collected in nine locations in the Republic of the Congo in 2017 following a north-south transect and reared to adult stage. Adults were morphologically identified, counted and grouped according to species and location. Genetic diversity of Ae. albopictus was assessed by analyzing the cytochrome oxidase I (COI) gene. Results: Ae. albopictus and Ae. aegypti were found together across the country in all the locations investigated. The invasive species is predominant over the native species in all locations except Brazzaville, suggesting that Ae. albopictus is displacing Ae. aegypti across Congo. When comparing the species distributions across the two largest cities, Brazzaville and Pointe Noire, Ae. albopictus was more prevalent than Ae. aegypti in the suburbs whereas the opposite situation was reported in the city centre. Mitochondrial DNA analysis revealed very low genetic diversity of Ae. albopictus with only three haplotypes recorded across the country supporting the recent introduction of this species in the Republic of the Congo. Phylogenetic tree analysis revealed that Ae. albopictus from Congo originated from other tropical Asian countries such as China, likely as a result of increasing trade links. Conclusion: These findings are important for the implementation of vector control strategies and can serve as a foundation for further research on these vectors in the country

Value of minimum intensity projections for chest CT in COVID-19 patients

Purpose: To investigate whether minimum intensity projection (MinIP) reconstructions enable more accurate depiction of pulmonary ground-glass opacity (GGO) compared to standard transverse sections and multiplanar reformat (MPR) series in patients with suspected coronavirus disease 2019 (COVID-19). Method: In this multinational study, chest CT scans of 185 patients were retrospectively analyzed. Diagnostic accuracy, diagnostic confidence, image quality regarding the assessment of GGO, as well as subjective time-efficiency of MinIP and standard MPR series were analyzed based on the assessment of six radiologists. In addition, the suitability for COVID-19 evaluation, image quality regarding GGO and subjective time-efficiency in clinical routine was assessed by five clinicians. Results: The reference standard revealed a total of 149 CT scans with pulmonary GGO. MinIP reconstructions yielded significantly higher sensitivity (99.9 % vs 95.6 %), specificity (95.8 % vs 86.1 %) and accuracy (99.1 % vs 93.8 %) for assessing of GGO compared with standard MPR series. MinIP reconstructions achieved significantly higher ratings by radiologists concerning diagnostic confidence (medians, 5.00 vs 4.00), image quality (medians, 4.00 vs 4.00), contrast between GGO and unaffected lung parenchyma (medians, 5.00 vs 4.00) as well as subjective time-efficiency (medians, 5.00 vs 4.00) compared with MPR-series (all P <.001). Clinicians preferred MinIP reconstructions for COVID-19 assessment (medians, 5.00 vs 3.00), image quality regarding GGO (medians, 5.00 vs 3.00) and subjective time-efficiency in clinical routine (medians, 5.00 vs 3.00). Conclusions: MinIP reconstructions improve the assessment of COVID-19 in chest CT compared to standard images and may be suitable for routine application

Role of aldosterone on lung structural remodelling and right ventricular function in congestive heart failure

<p>Abstract</p> <p>Background</p> <p>The mechanisms of benefit of mineralocorticoid receptors antagonists in congestive heart failure (CHF) are still debated. We hypothesized that aldosterone contributes to pulmonary remodelling and right ventricular (RV) dysfunction associated with CHF by stimulation of lung myofibroblasts (MYFs) proliferation.</p> <p>Methods</p> <p>Rats with moderate to large myocardial infarcts (MI) and CHF were studied. Two weeks after MI, spironolactone 100 mg/kg/day (n = 21) or no treatment (n = 24) were given for 3 weeks and compared to sham (n = 8).</p> <p>Results</p> <p>Infarct size was similar by ultrasound and pathologic measures in both MI groups.</p> <p>The MI-untreated group developed important lung remodelling with nearly doubling of dry lung weight (p < 0.01), reduced left ventricular (LV) fractional shortening (16 ± 2% vs. 53 ± 1%; mean ± SEM, p < 0.0001), pulmonary hypertension (RV systolic pressure: 40 ± 3 mmHg vs. 27 ± 1 mmHg, p < 0.01) and RV hypertrophy (RV/(LV + septum): 38 ± 3% vs. 24 ± 1%, p < 0.05). Spironolactone had no effect on these parameters and did not improve LV or RV performance (tricuspid annular plane systolic excursion and RV myocardial performance index) measured by echocardiography. CHF induced a restrictive respiratory syndrome with histological lung fibrosis: this was also unaffected by spironolactone. Finally, isolated lung MYFs did not proliferate after exposure to aldosterone.</p> <p>Conclusion</p> <p>Aldosterone does not significantly contribute to pulmonary remodelling and RV dysfunction associated with CHF. Other mechanisms are responsible for the beneficial effects of spironolactone in CHF.</p