Specific diversity, structure and carbon stock of urban plant formations in southern Benin

The sustainable management of urban green spaces requires the monitoring of the structural parameters of theirs trees. This study, which was carried out in the cities of Abomey-Calavi, Allada and Cotonou in southern Benin, aimed to describe the dendrometric parameters and the rate of carbon stored by urban trees. The inventory of trees planted in two types of urban forests (greened public spaces and shade rows) was performed using the roving survey method at the level of each city. Then, presence and absence data of all trees, as well as diameter at breast height (DBH) >= 10 cm and height >= 2 m were measured. These data were analyzed using R 4.0.5 software. The calculated dendrometric parameters were subjected to variance tests to assess their significance. The different counts allowed us to identify 5128 individual trees. The density per hectare varied from 36.7 to 83.1 between cities and from 40.5 to 80.4 between types of green spaces. Basal area varied from 2.25 to 11.4 m²/ha within cities. In all three cities in the study, trees had an aggregative spatial distribution, but with low numbers of individuals per site. All of the trees studied have a carbon sequestration rate of 689 t/ha. It is therefore necessary to take precautions for the strengthening and preservation of urban trees and their diversity for a more sustainable urban ecological balance. Keywords: Benin, Biomass, Carbon storage, Tree structure, Urban forest

Spatial Diagnosis and Conceptualisation of Greening Plan of Seme-Podji, Benin (West Africa)

Conservation and sustainable management of natural resources are increasingly recommended in decentralized territories. The most effective approach for this process is the participation of local communities because their knowledge is valuable in policy implementation. The study aims to propose a sustainable management model of a territory based on the needs of communities in order to conserve the natural resources in the Sèmè-Podji municipality in Benin, West Africa. Local knowledge and community’s needs have been used in association with GIS technics to make a diagnosis of the territory and propose a land use map for the municipality. The spatial diagnosis revealed an anthropization of the land cover, with a predominance of agro-systems, built up areas, croplands and fallow which represent 80.03% of the total area of the municipality. The marshlands which mostly serve as a refugium and support biodiversity represent 5.42%. The proposed plan showed that 84.79% (p ˂ 0.001) of socio-professional needs are explained. Therefore, the proposed actions were related to the restoration of ecological continuity, creation of new green recreational spaces, the protection of marshlands, the management of natural protected areas and the creation of fuel wood tree plantations. The current information can contribute to a sustainable and inclusive landscape planning for such municipalities, like our study site at Sèmè-Podji in Benin

GAD65 antibody prevalence and association with c-peptide, HLA class II alleles in Beninese patients with type 1 diabetes

Background: Antibodies to glutamic acid decarboxylase and particularly their isoforms in 65 kDa are one of markers for the diagnosis of the type 1 diabetes (T1D). The aim of this study is to assess the prevalence of GAD65 antibodies (GAD65Ab) and investigate the association of GAD65Ab with C-peptide values, HLA Class II alleles genotyping. The diagnosis of T1D was set up according to American Diabetes Association criteria.Methods: Radioimmunoassay was used to determine the GAD65Ab and C-peptide values. Class II HLA genotyping was performed in 51 patients with T1D and 51 healthy unrelated as control by using the PCR-SSP method. The sensitivity and specificity of the tests were calculated by standard formula.Results: Result revealed that GAD65Ab were present in 74.5% (38/51) of the patients with T1D. There was no significant difference between the positivity or the negativity of GAD65Ab and gender, onset and duration of diabetes, frequencies of HLA-DR4, HLA-DR3-DR4, HLA-DQB1*0201. However, GAD65Ab values are linked to C-peptide concentration (χ2 =15.73, P=0.0001), the presence of HLA-DR3 (χ2 =9.75, P= 0.002), HLA-DQA1*0501 (χ2 =4.09, P= 0.043) alleles. The GAD65Ab test sensitivity and specificity were 74.5% and 94.1%, respectively. The C-peptide test showed a sensitivity around 82.4 % and 86.3 % for the specificity.Conclusions: GAD65Ab showed to be a valuable early predictive marker and is associated with the risk to develop of T1D

Metrology in Africa: role of the CAFMET

This article presents the CAFMET (African Committee of Metrology), a non-profit organization that aims to meet the needs of African countries in the field of metrology. Its objectives are to spread a metrology culture in Africa via various domains in metrology such as, analysis, tests, and calibration. The difficulties of the development of metrology in Africa and the different activities, events and projects of the CAFMET are all presented

Interactions of melatonin with mammalian mitochondria. Reducer of energy capacity and amplifier of permeability transition.

Melatonin, a metabolic product of the amino acid tryptophan, induces a dose-dependent energy drop correlated with a decrease in the oxidative phosphorylation process in isolated rat liver mitochondria. This effect involves a gradual decrease in the respiratory control index and significant alterations in the state 4/state 3 transition of membrane potential (ΔΨ). Melatonin, alone, does not affect the insulating properties of the inner membrane but, in the presence of supraphysiological Ca2+, induces a ΔΨ drop and colloid-osmotic mitochondrial swelling. These events are sensitive to cyclosporin A and the inhibitors of Ca2+ transport, indicative of the induction or amplification of the mitochondrial permeability transition. This phenomenon is triggered by oxidative stress induced by melatonin and Ca2+, with the generation of hydrogen peroxide and the consequent oxidation of sulfydryl groups, glutathione and pyridine nucleotides. In addition, melatonin, again in the presence of Ca2+, can also induce substantial release of cytochrome C and AIF (apoptosis-inducing factor), thus revealing its potential as a pro-apoptotic agent

Diversite floristique et facteurs d’influence de la survie des jeunes arbres d’accompagnement de rue dans la ville de Cotonou : Floristic diversity and factors affecting the survival of young avenue trees in the city of Cotonou

De nombreux paramètres influencent la croissance des arbres d’accompagnement de rue, entrainant parfois la destruction ou l’échec des plantations d’alignement. Le présent travail a pour objectif d’analyser la contribution des facteurs de réussite et d’échec à la survie des jeunes plantations dans la ville de Cotonou. L’approche méthodologique utilisée a permis de dénombrer systématiquement tous les jeunes arbres plantés et de répertorier tous les facteurs d’influence de leur viabilité sur 20 kilomètres de rues nouvellement aménagées. Les paramètres de diversité sont calculés pour apprécier potentiel floristique, puis la liste des facteurs d’influence est établie, et mise en relation avec les quartiers traversés à travers une analyse factorielle des correspondances. Les résultats obtenus révèlent 1034 individus, répartis en 7 espèces de 7 familles différentes. L’indice moyen de diversité de Shannon (2,55±0,14 bits) et l’équitabilité de Pielou (0,91±0,05) révèlent la dominance de quelques espèces, dont les plus représentatives sont Spathodea campanulata P. Beauv. et Cordia sebestena L. avec respectivement 25,53 % et 19,05 % de l’effectif total des individus. Dix-neuf facteurs d’influence (14 facteurs de réussite et 5 facteurs d’échec) sont observés autours des jeunes plantations, avec une forte contribution des facteurs de réussite à la survie des arbres. Cette étude révèle qu’après la réalisation des plantations urbaines, il est important de mettre en place un dispositif de suivi afin de leur assurer une bonne croissance et un taux de réussite conséquent pour le bien-être des citadins. Many parameters influence the growth of avenue trees supporting roadways, sometimes leading to the destruction or failure of street trees. The objective of this work is to analyze the contribution of success and failure factors to the survival of young plantations in the city of Cotonou. The methodological approach used made it possible to systematically count all the young trees planted and to list all the factors influencing their viability on 20 kilometers of newly developed streets. The diversity parameters are calculated to assess plant potential, then the list of influencing factors is established, and related to the neighborhoods crossed through a factorial correspondence analysis. The results obtained reveal 1034 individuals, divided into 7 species from 7 different families. Shannon's mean diversity index (2.55 ± 0.14 bits) and Pielou fairness (0.91 ± 0.05) reveale the dominance of some species, the most representative of which are Spathodea campanulata P. Beauv. and Cordia sebestena L. with respectively 25.53% and 19.05% of the total number of individuals. Nineteen influencing factors (14 success factors and 5 failure factors) are observed around young plantations, with a strong contribution of success factors to tree survival. This study reveals that after the completion of urban plantations, it is important to set up a monitoring system in order to ensure good growth and a consequent success rate for the well-being of the city-dwellers

Identical and reduced-order synchronizations of some Josephson junctions model

In this work, the identical and reduced-order synchronizations between four different Josephson junction models are studied. First, we realized the synchronization between two Resistive–Capacitive–Inductive-Shunted Junction (RCLSJ) models taking into account its non-harmonic dynamics of the junction current IJ using the backstepping technique. Next, we showed that this third-order Josephson model can be synchronized with three other second-order Josephson models using both the feedback control technique and Lyapunov’s stability theory for different values of the non-harmonicity constant

Assessing the direct and indirect impacts of breeding activities on residential values: a spatial hedonic approach in Brittany

Agriculture contributes to the production of a large range of externalities. Their valuation is a critical issue for the design of agro-environmental policies. Hedonic pricing method allows for such valuation using house prices and attributes. However, several endogenous biases affect the estimation. Some of these biases are due to spatial effects, which arise when observations are spatially correlated. The objective of the paper is to apply latest developments of spatial econometrics on a hedonic model to estimate the value of agricultural externalities from Brittany (France). We focused especially on externalities from breeding. We distinguish between direct and spatially indirect impacts of nitrogen pollution, but also on green algae presence, i.e. a nitrogen-related pollution arising on Breton seacoasts for years. Using a database of 8,075 transactions from 2010 to 2012, we run several linear and spatial hedonic models. A Spatial Durbin Error Model (SDEM) is selected as the best model. Our estimations reveal that swine and poultry breedings reduce house prices while cattle breeding has almost no impact on house prices. We highlight that the pollution from swine and poultry overlaps from the municipality where the production occurs. The green algae pollution of the closest beach decreases houses prices by 13.5%. Acknowledgement : This research was funded by the EU s Horizon 2020 program under grant agreement n 633838 (PROVIDE project, http://www.provide-project.eu/). This work does not necessarily reflect the view of the EU and in no way anticipates the Commission s future policy

Epidemiology de l’hepatite virale B chez les Ogo du Togo : prevalence et marqueurs serologiques

But de l’étude: –L’épidémiologie des hépatites virales est peu connue dans les ethnies isolats du Togo. Cette étude a pour but d’évaluer la séroprévalence et l’évolution de l’hépatite virale B chez les Ogo.Patients et méthodes. – Une étude transversale a concerné 538 sujets apparemment sains 433 Ogo et 105 témoins vivant tous dans le même village. La créatinine, les transaminases et gamma-GT ont été dosées. Le dépistage de l’AgHBs et la recherche des marqueurs sériques antigènes et anticorps ont été effectués par immunochromatographie basée sur la technique double sandwich.Résultats. –L’Ag HBs était présent chez 9,96 % des Ogo et 18% des témoins. On observe que 2,94% des Ogo présentaient une hépatite aiguë ou chronique active. L’infection chronique était observée chez 6,05% des Ogo et 5% des témoins. Tandis que 6,2% des Ogo et 8% des témoins étaient guéris mais mal protégés. Les sujets convalescents étaient de 6,48% chez les Ogo et 5% chez les témoins. Les concentrations des transaminases étaient significativement plus élevées chez les témoins (p<0.001) que chez les Ogo.Conclusion: Cette étude révèle que la prévalence de l’HVB est moins élevée chez les Ogo que chez les témoins. Les 14% de la population qui sont des porteurs chroniques sont des sujets vecteurs pour de propagation du virus et présentent des risques de développer à long terme des cirrhoses ou un carcinome. Ces résultats devraient permettre la mise en place de programmes de sensibilisation et de prise en charge sanitaire plus efficaces des populations rurales.Mots clés: Hépatite virale B, Séroprévalence, Ethnie Ogo, TogoEnglish Title: Epidemiology of hepatitis viral B in Ogo population of Togo: prevalence and serological markers English AbstractObjectives: - Epidemiology of viral hepatitis is little known in Togolese isolated ethnic groups. The aim of this study was to investigate seroprevalence and evolution of viral hepatitis B in Ogo population.Patients and methods: - A cross-sectional study involved 538 apparently healthy subjects. They were 433 Ogo subjects and 105 control subjects all living in the same village. Creatinine, transaminases and gamma GT were performed. Screening of HBsAg and the detection of the viral markers: antigens and antibodies were performed by immunochromatography double sandwich technique.Results: Ag HBs was present in 9.96% of Ogo and 18% of controls. We observed that 2.94% of Ogo had acute or chronic hepatitis. Chronic hepatitis was observed in 6.05% Ogo and 5.01% controls. While 6.2% of Ogo and 8% of controls were cured but poorly protected and 6.48% of Ogo and 5% of control were convalescent. Transaminase concentrations were significantly elevated in controls subjects than Ogo (p <0.001).Conclusion - This study reveals that seroprevalence of viral hepatitis B was lower in Ogo than in control. The 14% of the population who are chronic carriers are potential subjects for spreading the virus and present risks of developing long-term cirrhosis or hepatocellular carcinoma. These results will allow to the setting up of a sensitization and health care programs for the rural populations.Keywords: Viral hepatitis B, seroprevalence, Ogo ethnic group, Tog