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Contains fulltext : 291985.pdf (Publisher’s version ) (Open Access) We describe the MalariaGEN Pf7 data resource, the seventh release of Plasmodium falciparum genome variation data from the MalariaGEN network. It comprises over 20,000 samples from 82 partner studies in 33 countries, including several malaria endemic regions that were previously underrepresented. For the first time we include dried blood spot samples that were sequenced after selective whole genome amplification, necessitating new methods to genotype copy number variations. We identify a large number of newly emerging crt mutations in parts of Southeast Asia, and show examples of heterogeneities in patterns of drug resistance within Africa and within the Indian subcontinent. We describe the profile of variations in the C-terminal of the csp gene and relate this to the sequence used in the RTS,S and R21 malaria vaccines. Pf7 provides high-quality data on genotype calls for 6 million SNPs and short indels, analysis of large deletions that cause failure of rapid diagnostic tests, and systematic characterisation of six major drug resistance loci, all of which can be freely downloaded from the MalariaGEN website.

Le maraîchage urbain joue un rôle très important dans la sécurité alimentaire et la résorption du chômage. Cependant, l’intensification des pratiques culturales peuvent altérer les propriétés physicochimiques des sols et réduire les rendements. La présente étude avait pour but de caractériser les pratiques culturales maraîchères à Brazzaville et de déterminer leur influence sur les propriétés physicochimiques des sols. Dans les sites retenus, des enquêtes structurées ont été menées auprès des maraîchers et des échantillons de sol ont été prélevés suivant des transects. Les analyses physiques et chimiques des sols ont été réalisées suivant les procédures courantes de laboratoire. Les résultats obtenus ont montré que les pratiques culturales dans les sites étudiés sont intensives. Les sols étudiés sont sableux à plus de 95%, acides, pauvres en matière organique et ont une CEC relativement faibles. Cependant on relève une sursaturation en bases échangeables sur l’ensemble des sites. Ainsi, cette sursaturation serait liée à l’intensification des pratiques culturales. Urban market gardening plays a very important role in food security and the reduction of unemployment. However, intensification of soil use can alter soil properties and reduce yields. This study aims to characterize vegetable farming practices in Brazzaville and to determine their influence on soil properties. In the selected sites, structured questionnaire was conducted among market gardeners and soil samples were taken following transects. Soil physical and chemical analyses were carried out following lab common procedures. The results showed that the cultivation practices in the sites studied are intensive. The soils studied are more than 95% sandy, acidic, low in organic matter and have a relatively low CEC. However, there is an oversaturation in exchangeable bases on all sites. Thus, this oversaturation would be linked to the intensification of cultural practices.

This study was performed to evaluate the change in seasonal abundance and distribution of individual mosquito vectors (Culex, Anopheles, and Aedes) in relation to the climatic factors in Eastern Province, Saudi Arabia, for the study period of 2014. The association between mosquito abundance and environmental parameters was investigated using bivariate and multivariate analysis. The study showed the range of temperature and relative humidity required for individual mosquito larvae abundance varies for Culex, Anopheles, and Aedes. However, no variation was observed in the range of temperature and relative humidity required for the abundance of adult Culex and Anopheles. The results revealed a negative relationship between mosquito larval/adult abundance and temperature (Total number of larva/adult is 671/11 in July, While it is 2462/221 in January). There is a link between relative humidity and rainfall, as the three climatic factors together were responsible for 33.1% (R2 = 0.331), 54.6% (R2 = 0.546), and 86.6% (R2 = 0.866) of the variance on Culex, Anopheles, and Aedes larvae, respectively. The effects of the three climatic parameters of temperature, relative humidity, and rainfall on mosquito larval and adult abundance were discussed. In addition, influences of other environmental factors on larval/adult mosquito distribution and abundance were also explained.

We describe the MalariaGEN Pf7 data resource, the seventh release of Plasmodium falciparum genome variation data from the MalariaGEN network. It comprises over 20,000 samples from 82 partner studies in 33 countries, including several malaria endemic regions that were previously underrepresented. For the first time we include dried blood spot samples that were sequenced after selective whole genome amplification, necessitating new methods to genotype copy number variations. We identify a large number of newly emerging crt mutations in parts of Southeast Asia, and show examples of heterogeneities in patterns of drug resistance within Africa and within the Indian subcontinent. We describe the profile of variations in the C-terminal of the csp gene and relate this to the sequence used in the RTS,S and R21 malaria vaccines. Pf7 provides high-quality data on genotype calls for 6 million SNPs and short indels, analysis of large deletions that cause failure of rapid diagnostic tests, and systematic characterisation of six major drug resistance loci, all of which can be freely downloaded from the MalariaGEN website.

Scanning electron microscopy picture of bacterial strains, and metabolites of benzo(a)pyrene generated by these bacteria.

Ce travail a pour objet de contribuer à la connaissance de l’orpaillage et de ses impacts dans l’environnement forestier du secteur de Souanké au Nord-Ouest de la République du Congo. La méthodologie est basée sur l’inventaire des types et des caractéristiques des exploitations, et sur une évaluation des impacts environnementaux observés à l’aide de la grille de Fecteau et des analyses au spectrophotomètre. La télédétection a servi à l’évaluation de la dégradation forestière. Occupant 18 sites sur les 20 identifiés, l’exploitation artisanale reste dominante (soit 90%) par rapport à celle semi-industrielle. L’exploitation artisanale est pratiquée par des Congolais et certains étrangers (Camerounais, Tchadiens, Ouest africains, Congolais de la RDC) organisés en équipes légères tandis que l’exploitation semi-industrielle est pratiquée par des sociétés chinoises. Les impacts négatifs relevés sur l’environnement du secteur sont : dégradation du couvert végétal, perturbation du milieu, excavations, stagnation des eaux et asphyxie des plantes, éboulements, modification du paysage, tas de graviers et morts terrains abandonnés, augmentation de la turbidité des eaux, perturbation du régime d’écoulement des cours d’eau, risques d’accident. Les impacts identifiés pour l’orpaillage semi-industriel et l’orpaillage artisanal sont respectivement : majeurs (50% vs 31%), moyens (29% vs 15%), mineurs (21% vs 54%). La turbidité est supérieure à 500 NTU du point de lavage jusqu’à 1000 m en aval dans les sites mécanisés alors qu’elle décroit rapidement en aval des sites traditionnels. La superficie forestière dégradée par les activités d’orpaillage est évaluée à 934 ha sur 13.912 ha, soit un taux de 6.7%.

Ce travail a pour objet de contribuer à la connaissance de l’orpaillage et de ses impacts dans l’environnement forestier du secteur de Souanké au Nord-Ouest de la République du Congo. La méthodologie est basée sur l’inventaire des types et des caractéristiques des exploitations, et sur une évaluation des impacts environnementaux observés à l’aide de la grille de Fecteau et des analyses au spectrophotomètre. La télédétection a servi à l’évaluation de la dégradation forestière. Occupant 18 sites sur les 20 identifiés, l’exploitation artisanale reste dominante (soit 90%) par rapport à celle semi-industrielle. L’exploitation artisanale est pratiquée par des Congolais et certains étrangers (Camerounais, Tchadiens, Ouest africains, Congolais de la RDC) organisés en équipes légères tandis que l’exploitation semi-industrielle est pratiquée par des sociétés chinoises. Les impacts négatifs relevés sur l’environnement du secteur sont : dégradation du couvert végétal, perturbation du milieu, excavations, stagnation des eaux et asphyxie des plantes, éboulements, modification du paysage, tas de graviers et morts terrains abandonnés, augmentation de la turbidité des eaux, perturbation du régime d’écoulement des cours d’eau, risques d’accident. Les impacts identifiés pour l’orpaillage semi-industriel et l’orpaillage artisanal sont respectivement : majeurs (50% vs 31%), moyens (29% vs 15%), mineurs (21% vs 54%). La turbidité est supérieure à 500 NTU du point de lavage jusqu’à 1000 m en aval dans les sites mécanisés alors qu’elle décroit rapidement en aval des sites traditionnels. La superficie forestière dégradée par les activités d’orpaillage est évaluée à 934 ha sur 13.912 ha, soit un taux de 6.7%.

"This book argues that renewable electrification in developing countries provides important opportunities for local economic development, but new pathways are required for turning these opportunities into successful reality. Building Innovation Capabilities for Sustainable Industrialisation offers a novel input into the debate on development of capabilities for sustainable industrialisation and delivers key insights for both researchers and policy makers when it comes to the question of how to increase the economic co-benefits of renewables expansion. The chapters in the book use a tailored analytical framework in their studies of renewable electrification efforts in Kenya and other countries in sub-Saharan Africa. They draw on a mix of project, sector and country level case studies to address questions such as: What capabilities are developed through on-going renewable electrification projects in developing economies? How can the expansion of renewable electrification be supported in a way that also encourages sustainable economic development? What role do international linkages (South-South and North-South) play and what role should they play in the greening of energy systems in developing economies? The authors provide a new understanding of how green transformation and sustainable industrialisation can be combined, highlighting the opportunities and constraints for local capability building and the scope for local policy action. This book will be of great interest to students and scholars of development studies, energy studies, sustainability and sustainable development, as well as practitioners and policy makers working in development organisations and national governments"

This book argues that debates about renewable electrification must move beyond their predominant focus on access to clean energy. Increased access to electricity makes important contributions to sustainable development but it does not produce the full range of co-benefits which can arise from green energy investments. The book argues that policy makers need to start focusing more heavily on questions of the development of local activities and capabilities in designing, constructing, and operating renewable electricity infrastructure. A key issue is the degree to which sustainable access to clean energy will be sustainable when these renewable energy supply mechanisms are often designed, constructed, operated, and maintained predominantly with foreign equipment, foreign financing, and foreign workers. This is what this book sets out to examine and discuss in the context of green industrialisation discourses. This chapter outlines the background to the sustainable industrialisation debate. It also specifies the objectives and provides an overview of the book and its key themes.

This chapter is structured as follows: the next section reiterates the key research themes addressed in this book in order to situate the findings in wider debates about pathways to sustainable industrialisation. The following section forms the bulk of the chapter. It conveys the findings regarding the relative importance and dynamics of different aspects of renewable electrification for enhancing capability outcomes. It is structured around aspects related to the three key themes of the book, (a) projects design, organisation and linkages, (b) deployment model and choice of technology and (c) policies and political actors at the national and international level. The final section brings out the implications for policy. We summarise key findings arising from the research presented in this book, with the hope that the pointers for policy action can prove useful for more sustainable pathways that combine primary energy benefits and secondary localised economic co-benefits in the context of renewable electrification and the green transformation more broadly.

Silk being one of the organic natural fibers, is susceptible to microorganisms attack thus leading to loss of physical aesthetic and mechanical properties. The present study was focused on optimizing the dyeing process parameters (Extract concentration and dyeing temperature) of dyestuff extracts from the Galinsoga Parviflora plant and analyzing the antibacterial activity of the dyed silk fabric. The Pad-dry method was used for the application of herbal dye extract onto selected silk fabric and the AATCC 100:2019 test method was used in assessing the treated fabric quantitatively against Staphylococcus Aureus and Pseudomonas Aeruginosa bacterial strains. Dyeing conditions obtained using Central Composite Design (CCD) indicated that dye concentration and temperature of 39.14 percent and 700C respectively could be deemed as optimum. Also, the Analysis of Variance (ANOVA) results showed that extract concentration has a statistically significant effect on bacterial count whereas the effect of temperature was not so much influential. Silk fabric dyed with optimized values demonstrated a 99.33% and 99.15% reduction in the bacterial count against Staphylococcus Aureus and Pseudomonas Aeruginosa bacterial strains respectively. Also, its fastness properties to light, washing, and Rubbing ranged from very good to excellent (4-5 to 5). Thus, in general, this research confirmed that Galinsoga Parviflora plant leaves, abundantly available in most parts of Uganda can be used as an antibacterial finish on silk fabric for improved bacterial resistance.

Thus far, only a handful of bacterial strains that can independently degrade and utilize benzo[a]pyrene (BaP) as the sole carbon source have been isolated and characterized. Here, three new bacterial strains, JBZ1A, JBZ2B, and JBZ5E, were isolated from contaminated soil and, using 16S rRNA sequencing, were identified as Bradyrhizobium japonicum, Micrococcus luteus, and Bacillus cereus, respectively. The growth ability of each individual strain and a consortium of all strains in the presence of BaP (4–400 µmol·l−1, pH 7, 37°C) was identified by the doubling time (dt). The results illustrated that dt decreased with increasing BaP concentrations for individual strain and the consortium. The optimum growth conditions of the consortium were 37°C, 0.5% NaCl (w/v), and pH 7. Under these conditions, the degradation rate was 1.06 µmol·l−1·day−1, whereas that of individual strains ranged 0.9–0.38 µmol·l−1·day−1. B. cereus had the strongest contribution to the consortium’s activity, with a degradation rate of 0.9 µmol·l−1·day−1. The consortium could also remove BaP spiked with soil, but at a lower rate (0.01 µmol.l−1.day−1). High-performance liquid chromatography–high-resolution tandem mass spectrometry permitted the detection of the metabolites of these strains, and a biodegradation pathway has been proposed.

The study was conducted in Brazzaville, and data collection covers the period from May to June 2017. The methodology is based on literature review and floristic and equipment inventory. Nine green spaces spread over two out of nine townships in the capital city. Four are located in Bacongo and five in Poto-Poto. According to the classification standards, 5 squares and 4 gardens were studied. Except for one square, all the others, including the gardens, are planted with trees. The equipment inventory lists 183 benches, including 63.83% permanently and/or partially in the sun, 4 playgrounds, no games for children, and 3 cultural monuments. The flora and health of the trees stands shows 186 trees and 279 shrubs, all corresponding to 26 species. An examination of the health status reveals that 57% of trees show anthropogenic injuries. Floral analysis shows that exotic plants (76.92%) predominate over local plants (23.07%). The average basal area of trees in all green spaces is 1.95 m2·ha−1. The diametric structure is erratic within all green spaces, with a dominance of large diameter subjects. This leads to poor natural regeneration of woody plants. The green spaces in Brazzaville, which are very unevenly distributed within the urban fabric, do not meet the international standards disseminated by the World Health Organization (WHO) and do not fully play their biodiversity conservation and recreational and ecological functions. History of green spaces in Brazzaville states that no creation was born after independence. The existing land has been reduced in size, and the new land has been used for other purposes.

Avec l’adhésion tardive de la République Démocratique du Congo à l’espace OHADA, il s’est posé les problèmes de vulgarisation à grande échelle et d’appropriation de l’ancien acte par les différents utilisateurs. Avec la révision de l’ancien acte menant vers les IFRS, les mêmes problèmes se posent encore avec acuité. Dans le souci de faciliter l’appropriation du nouvel acte comptable de l’OHADA, cette étude tente de ressortir à l’attention des théoriciens et praticiens de la comptabilité exerçant dans l’espace OHADA, quelques innovations majeures et améliorations opérées dans l’acte uniforme relatif au droit comptable et à l’information financière. Celles-ci se rapportent aux traitements des charges immobilisées, des frais de recherche et développement, des contrats pluri-exercices, des frais accessoires d’achat, les instruments de monnaies électroniques, l’approche par composant et l’attribution gratuite d’actions au personnel et dirigeant. Nous procéderons par analyse comparative des traitements comptables de l’ancien acte à ceux de l’acte révisé.

Avec l���adh��sion tardive de la R��publique D��mocratique du Congo �� l���espace OHADA, il s���est pos�� les probl��mes de vulgarisation �� grande ��chelle et d���appropriation de l���ancien acte par les diff��rents utilisateurs. Avec la r��vision de l���ancien acte menant vers les IFRS, les m��mes probl��mes se posent encore avec acuit��. Dans le souci de faciliter l���appropriation du nouvel acte comptable de l���OHADA, cette ��tude tente de ressortir �� l���attention des th��oriciens et praticiens de la comptabilit�� exer��ant dans l���espace OHADA, quelques innovations majeures et am��liorations op��r��es dans l���acte uniforme relatif au droit comptable et �� l���information financi��re. Celles-ci se rapportent aux traitements des charges immobilis��es, des frais de recherche et d��veloppement, des contrats pluri-exercices, des frais accessoires d���achat, les instruments de monnaies ��lectroniques, l���approche par composant et l���attribution gratuite d���actions au personnel et dirigeant. Nous proc��derons par analyse comparative des traitements comptables de l���ancien acte �� ceux de l���acte r��vis��.

This chapter is structured as follows: the next section reiterates the key research themes addressed in this book in order to situate the findings in wider debates about pathways to sustainable industrialisation. The following section forms the bulk of the chapter. It conveys the findings regarding the relative importance and dynamics of different aspects of renewable electrification for enhancing capability outcomes. It is structured around aspects related to the three key themes of the book, (a) projects design, organisation and linkages, (b) deployment model and choice of technology and (c) policies and political actors at the national and international level. The final section brings out the implications for policy. We summarise key findings arising from the research presented in this book, with the hope that the pointers for policy action can prove useful for more sustainable pathways that combine primary energy benefits and secondary localised economic co-benefits in the context of renewable electrification and the green transformation more broadly.

National audience

Polycyclic aromatic hydrocarbons (PAHs), which consist of low-molecular-weight PAHs (LMW-PAHs) and high-molecular-weight PAHs (HMW-PAHs), form an important class of pollutants. Pyrene and benzo[a]pyrene (BaP) are the main pollutants belonging to HMW-PAHs, and their degradation by microorganisms remains an important strategy for their removal from the environments. Extensive studies have been carried out on the isolation and characterisation of microorganisms that actively degrade LMW-PAHs, and to a certain extent, the HMW-PAH pyrene. However, so far, limited work has been carried out on BaP biodegradation. BaP consists of five fused aromatic rings, which confers this compound a high stability, rendering it less amenable to biodegradation. The current review summarizes the emerging reports on BaP biodegradation. More specifically, work carried out on BaP bacterial degradation and current knowledge gaps that limit our understanding of BaP degradation are highlighted. Moreover, new avenues of research on BaP degradation are proposed, specifically in the context of the development of “omics” approaches

Petroleum products consist mainly of aliphatics, aromatics, asphaltenes and resins. After oil exploitation, the concentrations of asphaltenes and resins are high in oil reservoirs; however, they are also the petroleum pollutants most recalcitrant to degradation, leading to high oil viscosity. A sizable amount of work has been dedicated to understand the degradation mechanisms of aliphatics and aromatics; however, in comparison, little work has been carried out on asphaltene and resin degradation. This review discusses our current knowledge on the understanding of asphaltene and resin degradation. More specifically, it sheds light on work carried out to date on the degradation of these pollutants, and highlights the major gaps that limit our understanding of their degradation pathways. It also presents new potential research areas that can be explored to fill in these gaps.

This chapter is structured as follows: the next section reiterates the key research themes addressed in this book in order to situate the findings in wider debates about pathways to sustainable industrialisation. The following section forms the bulk of the chapter. It conveys the findings regarding the relative importance and dynamics of different aspects of renewable electrification for enhancing capability outcomes. It is structured around aspects related to the three key themes of the book, (a) projects design, organisation and linkages, (b) deployment model and choice of technology and (c) policies and political actors at the national and international level. The final section brings out the implications for policy. We summarise key findings arising from the research presented in this book, with the hope that the pointers for policy action can prove useful for more sustainable pathways that combine primary energy benefits and secondary localised economic co-benefits in the context of renewable electrification and the green transformation more broadly.

To date, only a handful of bacterial strains that can independently degrade and utilize benzo[a]pyrene (BaP) as the sole carbon source has been isolated and characterized. Here, three new bacterial strains—JBZ1A, JBZ2B, and JBZ5E—were isolated from contaminated soil and, using 16S rRNA sequencing, were identified as Brad rhizobium japonicum, Micrococcus luteus, and Bacillus cereus, respectively. The growth ability of each individual strain and a consortium of all strains in the presence of BaP (4–400 µmol·L−1, pH 7, 37 °C) was identified by the doubling time (dt). The results illustrate that dt decreased with increasing BaP concentrations for individual strains and the consortium. The optimum growth conditions of the consortium were 37 °C, 0.5% NaCl (w/v), and pH 7. Under these conditions, the degradation rate was 1.06 µmol·L−1·day−1, whereas that of individual strains ranged from 0.9 to 0.38 µmol·L−1·day−1. B. cereus had the strongest contribution to the consortium’s activity, with a degradation rate of 0.9 µmol·L−1·day−1. The consortium could also remove BaP spiked with soil but at a lower rate (0.01 µmol L−1.day−1). High-performance liquid chromatography–high-resolution tandem mass spectrometry permitted the detection of the metabolites of these strains, and a biodegradation pathway is proposed.

Rumex vesicarius (RVE) mediated chitosan–AgNPs composite was produced in situ by using an aqueous extract of Rumex vesicarius leaves as the reducing agent to reduce Ag+ to Ag0. The synthesized composite was evaluated as a sweet (CO2) corrosion inhibitor (CI) for C1018 carbon steel (CS) in 3.5 wt% NaCl solution under static and hydrodynamic conditions. The corrosion inhibitive performance was evaluated using electrochemical impedance spectroscopy (EIS), linear polarization resistance (LPR), and potentiodynamic polarization (PDP) techniques, as well as scanning electron microscopy (SEM)/energy dispersive X-ray spectroscopy (EDAX), and atomic force microscopy (AFM) on corroded C1018 CS without and with additives. The effect of concentration, immersion time, temperature, and rotation speed on the CI performance of the composite was also investigated. The corrosion inhibitive effect increased with increasing composite dosage, with the highest inhibition efficiency (IE) acquired at the maximum composite dosage of 0.3%. Beyond this concentration, the IE decline with increasing concentration. Furthermore, IE was found to increase with immersion time and decline with a temperature rise from 25 to 40 °C, with the optimum temperature of 60 °C found to accelerate corrosion without and with RVE-mediated Chi–AgNPs composite. Under high shear stress, the Chi–AgNPs composite exhibits moderate corrosion inhibition under hydrodynamic conditions. The surface analysis results validate the formation of a protective covering due to composite adsorption on the CS surface. The RVE-mediated chitosan–AgNPs composite could be recommended as a CI for C1018 CS in sweet (CO2) corrosion environments at ambient temperature.

Ce travail a pour objet de contribuer à la connaissance de l’orpaillage et de ses impacts dans les écosystèmes forestiers du secteur de Souanké au Nord-Ouest de la République du Congo. La méthodologie est basée sur l’inventaire des types et des caractéristiques des exploitations, et sur une évaluation des impacts environnementaux observés à l’aide de la grille de Fecteau et des analyses au spectrophotomètre. La télédétection a servi à l’évaluation de la dégradation forestière. Occupant 18 sites sur les 20 identifiés, l’exploitation artisanale reste dominante (soit 90%) par rapport à celle semi-industrielle. L’exploitation artisanale est pratiquée par des Congolais et certains étrangers (Camerounais, Tchadiens, Congolais de la RDC et des ressortissants des pays Ouest africains,) organisés en équipes légères tandis que l’exploitation semi-industrielle est pratiquée par des sociétés chinoises. Les impacts négatifs relevés sur l’environnement du secteur sont : dégradation du couvert végétal, perturbation du milieu faunique, excavations, stagnation des eaux et asphyxie des plantes, éboulements, modification du paysage, amoncellements de graviers et morts-terrains, augmentation de la turbidité des eaux, perturbation du régime d’écoulement des eaux, risques d’accident. Les impacts identifiés pour l’orpaillage semi-industriel et artisanal sont respectivement : majeurs (50 % vs 31%) ; moyens (29% vs 15%) ; mineurs (21% vs 54%). La turbidité est supérieure à 500 UTN du point de lavage jusqu’à 1000 m en aval dans les sites mécanisés alors qu’elle décroit rapidement en aval des sites traditionnels. La superficie forestière dégradée par les activités d’orpaillage est évaluée à 934 ha sur 13.912 ha, soit un taux de 6.7%. The aim of this work is to contribute to the knowledge of gold artisanal mining and its impacts in the forest ecosystems of Souanké sector in the northwest of the Republic of Congo. The methodology is based on an inventory of the types and characteristics of mining operations, and on an assessment of the environmental impacts observed using the Fecteau grid and spectrophotometer analyses. Remote sensing was used to assess forest degradation. Of the 20 sites identified, 18 are dominated by artisanal mining (90%) compared to semi-industrial mining. Artisanal mining is carried out by Congolese and some foreigners (Cameroonians, Chadians, West Africans, and Congolese from the DRC) and organized in small teams, whereas semi-industrial mining is carried out by Chinese companies. The negative impacts noted on the environment of the sector are degradation of the vegetation cover, environmental disturbance, excavations, stagnation of water and asphyxiation of plants, landslides, modification of the landscape, heaps of gravel and dead land abandoned, increase in water turbidity, disturbance of the flow regime of watercourses, risks of accidents. The impacts identified for semi-industrial and artisanal gold mining are respectively: major (50% vs. 31%), medium (29% vs. 15%), and minor (21% vs. 54%). Turbidity is above 500 NTU from the washing point to 1000m downstream in mechanized sites, whereas it decreases rapidly downstream in artisanal sites. The forest area degraded by gold mining activities is estimated at 934 ha out of 13,912 ha, corresponding to a rate of 6.7%.

Located in the hearth of Africa, the Congo basin is the world’s second largest rainforest ecosystem, spanning over nine countries including the Republic of the Congo. Nature-based solutions, i.e., afforestation, reforestation or agroforestry supplying wood energy, halting food insecurity, restoring land desertification and fostering mitigation and adaptation to climate warming, have been increasingly used in the past decades. Within this framework, Congolese coastal plains have been afforested using fast growing trees since the early 1950s. Due to the low forest productivity and soil fertility, sustainable management of these forest ecosystems (trees, soils and environment) have been performed. Improved germplasms, increased stand wood biomass and healthier soils have the potential to enhance wood and fuel wood energy supply, mitigation and adaptation to climate change, food security, restoration of land and ecosystem biodiversity. This meets ten out of the seventeen sustainable development goals (SDG #), specifically goals related to alleviating poverty (1) and hunger (2), improving health (3), education (4), sanitation and access to clean water (6). Other goals include providing affordable clean energy (7), sustainable production and consumption (12), action on climate change (13), life on land (15), and partnerships for goals (17). Nature-based solutions help to face important societal challenges meeting more than half of SDGs of the United Nations.

We report a new assay system for the detection of miR-21 in cancer cells. The new assay works at room temperature and it does not involve enzymatic amplification. It consists a hairpin smart probe, designed to specifically recognize miR-21 target sequence. We tested the performance and sequence recognition capability of the smart probe to confirm desired specifications. We used the smart probe for the sequence-specific recognition of synthetic miR-21 oligonucleotides as well as mismatch sequences and we found that the probe recognizes the target sequence-specifically, while discriminating against mismatched sequences. We determined the limit of detection and limit of quantitation for the miR-21 oligonucleotides to be 1.72 nM and 5.78 nM, respectively, while the sensitivity is 6.90 × 10

The study aimed at evaluating the natural regeneration of some characteristic species in the Loukaya peri-urban forest was carried out in Brazzaville, over three surveys of one hectare each. The botanical inventory of the 23 species monitored covers the subjects of 2 ≤ d0.20 < 10 cm and d1.30 ≥ 10 cm. The study shows 1255 individuals of which 68.27% are 2 ≤ d0.20 < 10 cm. While being tropophilic and mesophilic, this ecosystem is pauciflorous and paucispecific. The phytoecological data show that this formation, which is a link in the African dense humid forest, presents values far below those known elsewhere; while being faithful to the forests of the Cataractes Plateau. As for the rate of natural regeneration, this index is greater than or equal to 100 for 69.56% of the taxa. Sarcochores and heliophytes are the taxa that best support this natural regeneration. This high rate of regeneration would be correlated with the high level of anthropization, whose large canopy gaps are accompanied by a flow of light conducive to the installation of seedlings.

The synthesis of geological and petroleum research undertaken in the coastal Sedimentary Basin of the Pointe-Noire region enabled the establishment of a lithostratigraphic scale. It has been observed that the order in which the series observed in outcrop and those encountered by deep wells succeed each other has allowed a value to be given to this relative scale. The study area corresponds to a longitudinal tectonic accident, fault or flexure. It belongs to the Cretaceous and Tertiary coastal sedimentary basin covered by the Plio-Pleistocene age formations (series of circuses), formed of highly permeable sands comprising multiple resistant horizons that store large bodies of water whose reserves are considered very important. Hydrographic network is composed of four main basins with a mediocre size. The quality of this groundwater is considered to be satisfactory for household consumption, but the sustainable management of these reserves requires constant checks on their quality as well as on the level of the reserves. All these resources put the agglomeration of Pointe-Noire close to large exploitable water reserves that meet the need for drinking water, even if, on the whole, the agglomeration is still experiencing many difficulties in terms of its drinking water supply.

MalariaGEN is a data-sharing network that enables groups around the world to work together on the genomic epidemiology of malaria. Here we describe a new release of curated genome variation data on 7,000 Plasmodium falciparum samples from MalariaGEN partner studies in 28 malaria-endemic countries. High-quality genotype calls on 3 million single nucleotide polymorphisms (SNPs) and short indels were produced using a standardised analysis pipeline. Copy number variants associated with drug resistance and structural variants that cause failure of rapid diagnostic tests were also analysed. Almost all samples showed genetic evidence of resistance to at least one antimalarial drug, and some samples from Southeast Asia carried markers of resistance to six commonly-used drugs. Genes expressed during the mosquito stage of the parasite life-cycle are prominent among loci that show strong geographic differentiation. By continuing to enlarge this open data resource we aim to facilitate research into the evolutionary processes affecting malaria control and to accelerate development of the surveillance toolkit required for malaria elimination.

MalariaGEN is a data-sharing network that enables groups around the world to work together on the genomic epidemiology of malaria. Here we describe a new release of curated genome variation data on 7,000 Plasmodium falciparum samples from MalariaGEN partner studies in 28 malaria-endemic countries. High-quality genotype calls on 3 million single nucleotide polymorphisms (SNPs) and short indels were produced using a standardised analysis pipeline. Copy number variants associated with drug resistance and structural variants that cause failure of rapid diagnostic tests were also analysed. Almost all samples showed genetic evidence of resistance to at least one antimalarial drug, and some samples from Southeast Asia carried markers of resistance to six commonly-used drugs. Genes expressed during the mosquito stage of the parasite life-cycle are prominent among loci that show strong geographic differentiation. By continuing to enlarge this open data resource we aim to facilitate research into the evolutionary processes affecting malaria control and to accelerate development of the surveillance toolkit required for malaria elimination.

Investments in renewable energy are increasing rapidly in sub-Saharan Africa. An interesting trend to note is the rapid increase and likely future growth of Chinese involvement in large-scale renewable-energy infrastructure projects. Our focus in this chapter is to determine the extent of co-benefits created when renewable-energy projects are developed by Chinese investors. For this, we undertake an in-depth micro-level analysis of three Chinese renewable-energy investment projects in hydro (Ghana), wind (Ethiopia), and solar photovoltaic (PV) (Kenya), based on primary data. Overall, we find evidence of ‘bounded benefits'. On the one hand, we can identify some newly created jobs, linkages generated with actors in local systems of production, and training activities involving local staff. On the other hand, the extent of these benefits is very limited. The results suggest that policymakers should be wary of overly optimistic expectations when it comes to assessing the co-benefits of renewable energy projects in the context of scarce pre-existing capabilities. However, the adoption of pro-active strategies and the implementation of carefully designed policies can increase the local economic co-benefits.

Contains fulltext : 238195.pdf (Publisher’s version ) (Open Access) MalariaGEN is a data-sharing network that enables groups around the world to work together on the genomic epidemiology of malaria. Here we describe a new release of curated genome variation data on 7,000 Plasmodium falciparum samples from MalariaGEN partner studies in 28 malaria-endemic countries. High-quality genotype calls on 3 million single nucleotide polymorphisms (SNPs) and short indels were produced using a standardised analysis pipeline. Copy number variants associated with drug resistance and structural variants that cause failure of rapid diagnostic tests were also analysed. Almost all samples showed genetic evidence of resistance to at least one antimalarial drug, and some samples from Southeast Asia carried markers of resistance to six commonly-used drugs. Genes expressed during the mosquito stage of the parasite life-cycle are prominent among loci that show strong geographic differentiation. By continuing to enlarge this open data resource we aim to facilitate research into the evolutionary processes affecting malaria control and to accelerate development of the surveillance toolkit required for malaria elimination.

Renewable energy systems provide a resilient access pathway to affordable and sustainable energy for millions of people in regions with no or undeserved grid. In this work, a multi-objective Hybrid Optimization Model for Electric Renewables (HOMER) software has been applied to design and assess the techno-economic feasibility of Hybrid Renewable Energy Systems (HRESs) for Malawi’s off-grid communities. The study targeted the use of decentralized photovoltaic (PV), wind, diesel generator, and battery storage technologies to electrify three villages of Chigunda, Mdyaka, and Kadzuwa, which had estimated daily electrical energy peak demands of 14.53, 8.09, and 6.40 kW, respectively. Wind and solar resource data were used as inputs to generate multiple combinations of energy systems in HOMER. The sensitivity of the output systems was tested by varying the wind velocity and diesel pump prices. The optimization results showed that for Chigunda, the optimal configuration comprised PV-wind-battery, while for Mdyaka and Kadzuwa, the PV-battery combinations were ideal. In all the cases, the optimal systems were more sensitive to changes in wind velocity. The systems were, however, found to be infeasible economically as the costs of energy were higher than the per kilowatt-hour cost of US$ 0.120 for electricity in Malawi.

MalariaGEN is a data-sharing network that enables groups around the world to work together on the genomic epidemiology of malaria. Here we describe a new release of curated genome variation data on 7,000 Plasmodium falciparum samples from MalariaGEN partner studies in 28 malaria-endemic countries. High-quality genotype calls on 3 million single nucleotide polymorphisms (SNPs) and short indels were produced using a standardised analysis pipeline. Copy number variants associated with drug resistance and structural variants that cause failure of rapid diagnostic tests were also analysed. Almost all samples showed genetic evidence of resistance to at least one antimalarial drug, and some samples from Southeast Asia carried markers of resistance to six commonly-used drugs. Genes expressed during the mosquito stage of the parasite life-cycle are prominent among loci that show strong geographic differentiation. By continuing to enlarge this open data resource we aim to facilitate research into the evolutionary processes affecting malaria control and to accelerate development of the surveillance toolkit required for malaria elimination.

Summary The oldest known shipwreck in southern Africa was found in Namibia in 2008. 1 , 2 , 3 , 4 Forty tons of cargo, including gold and silver coins, helped identify the ship as the Bom Jesus, a Portuguese nau (trading vessel) lost in 1533 while headed to India. 4 , 5 , 6 The cargo included >100 elephant tusks, 7 which we examined using paleogenomic and stable isotope analyses. Nuclear DNA identified the ivory source as African forest (Loxodonta cyclotis) rather than savanna (Loxodonta africana) elephants. Mitochondrial sequences traced them to West and not Central Africa and from ≥17 herds with distinct haplotypes. Four of the haplotypes are known from modern populations; others were potentially lost to subsequent hunting of elephants for ivory. Stable isotope analyses (δ13C and δ15N) indicated that the elephants were not from deep rainforests but from savanna and mixed habitats. Such habitats surround the Guinean forest block of West Africa 8 and accord with the locations of major historic Portuguese trading ports. 9 , 10 West African forest elephants currently range into savanna habitats; 11 , 12 , 13 our findings suggest that this was not consequent to regional decimation of savanna elephants for their ivory in the 19th and 20th centuries. During the time of the Bom Jesus, ivory was a central driver in the formation of maritime trading systems connecting Europe, Africa, and Asia. Our integration of paleogenomic, archeological, and historical methods to analyze the Bom Jesus ivory provides a framework for examining vast collections of archaeological ivories around the world, in shipwrecks and other contexts.

Three strains of novel bacteria were isolated from oil-contaminated sediment from the Arabian Gulf (Brevibacillus brevis T2C2008, Proteus mirabilis T2A12001, and Rhodococcus quinshengi TA13008). The isolated strains were tested for their degrading efficacy of low and high molecular hydrocarbon (naphthalene and pyrene). The efficacy of the two-hydrocarbon degradation by the isolates bacterial was determined at a temperature of 25 °C and 37 °C and pH of 5.0 and 9.0. In inoculated media at 37 °C, Rhodococcus qinshengi fully metabolized naphthalene and degrade 56% of pyrene. Brevibacillus brevis break down over 80% of naphthalene at room temperatures (25 °C). However, it was found that P. mirabilis and R. qinshengi biodegraded nearly 94% of naphthalene in the incubated media. The capacity for pyrene and naphthalene degradation in varying pH and temperature conditions was shown to be significant in Rhodococcus qinshengi because of its mineralization exceeding 50% across the tested pH and temperature. This implies that the isolated strains are ideal for biodegradation of contaminated sediment with naphthalene and pyrene.

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Chitosan/silver nanofluids were prepared using Phoenix dactylifera (DPLE) or Rumex vesicarius (HEL) extracts as the reducing agent, characterized using Fourier-transform infrared spectroscopy (FTIR), ultraviolet&ndash, visible (UV-vis), X-ray diffraction (XRD), and transmission electron microscope (TEM). The antimicrobial effect of the nanofluids against Gram positive, Bacillus licheniformis, Staphylococcus haemolyticus, Bacillus cereus, and Micrococcus luteus, and Gram-negative Pseudomonas aeruginosa, Pseudomonas citronellolis, and Escherichia coli bacteria has been studied. The nanoparticles were polydispersed in the chitosan matrix and are highly stable. The zeta potential of the silver nanoparticles in DPLE- and HEL-mediated composites is +46 mV and +56 mV, respectively. The FTIR results reveal that the free carboxylate groups in the plant biomaterial took part in stabilization process. HEL is a stronger reducing agent than DPLE and nanoparticles generated with HEL are smaller (8.0&ndash, 36 nm) than those produced with DPLE (10&ndash, 43 nm). DPLE- and HEL-mediated composites effectively inhibit the growth of the studied bacteria but HEL-mediated composite exhibited higher effect. The higher antimicrobial activity of HEL-mediated composite is linked to the smaller nanoparticles. The foregoing results indicate that HEL extract can be used in the green production of potential antimicrobial chitosan/silver nanofluids for biomedical and packaging applications.

Chitosan-copper oxide (CHT-CuO) nanocomposite was synthesized using olive leaf extract (OLE) as reducing agent and CuSO4⋅5H2O as precursor. CHT-CuO nanocomposite was prepared using an in situ method in which OLE was added to a solution of chitosan and CuSO4⋅5H2O mixture in the ratio of 1:5 (v/v) and heated at a temperature of 90 °C. The obtained CHT-CuO nanocomposite was characterized using field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), ultraviolet-visible (UV-Vis) spectrophotometry, energy-dispersive X-ray spectroscopy (EDAX), Fourier transform infrared spectroscopy (FTIR), and high-resolution transmission electron microscopy (TEM). TEM results indicated that CHT-CuO nanocomposite are spherical in shape with size ranging from 3.5 to 6.0 nm. Antibacterial activity of the synthesized nanocomposites was evaluated against Gram-positive (Bacillus cereus, Staphyloccous haemolytica and Micrococcus Luteus) and Gram-negative (Escherichia coli, Pseudomonas citronellolis, Pseudomonas aeruginosa, kliebisella sp., Bradyrhizobium japonicum and Ralstonia pickettii) species by cup platting or disc diffusion method. Overall, against all tested bacterial strains, the diameters of the inhibition zone of the three nanocomposites fell between 6 and 24 mm, and the order of the antimicrobial activity was as follows: CuO-1.0 > CuO-0.5 > CuO-2.0. The reference antibiotic amoxicillin and ciprofloxacin showed greater activity based on the diameter of zones of inhibition (between 15–32 mm) except for S. heamolytica and P. citronellolis bacteria strains. The nanocomposites MIC/MBC were between 0.1 and 0.01% against all tested bacteria, except S. heamolityca (>0.1%). Based on MIC/MBC values, CuO-0.5 and CuO-1.0 were more active than CuO-2.0, in line with the observations from the disc diffusion experiment. The findings indicate that these nanocomposites are efficacious against bacteria; however, Gram-positive bacteria were less susceptible. The synthesized CHT-CuO nanocomposite shows promising antimicrobial activities and could be utilized as an antibacterial agent in packaging and medical applications.

This paper discusses the prospects for developing production and innovation capabilities arising from renewable electrification efforts. This discussion falls at the intersection of several literatures within innovation studies and development studies. It requires a combination of ideas from across several academic fields of study. This paper focuses on value chain linkages and interactive learning. Because this is largely unexplored terrain, the paper seeks to provide conceptual framing based on insights from the literature and it discusses whether linkages within the global South offer specific advantages over North–South linkages. It then uses this conceptual framing to draw insights from the case of renewable electrification with wind and solar PV in Kenya. It ends by identifying key avenues for promoting interactive learning in this context.