Evaluation de la charge polluante des rivières des eaux usées ménagères et pluviales dans la ville de Bukavu, République Démocratique du Congo

La présente étude porte sur l’évaluation de la charge polluante des rivières dans la ville de Bukavu. Les paramètres de pollution, mesurés dans cette étude sont la demande chimique en oxygène (DCO), l’azote total et le phosphore total, et la demande biochimique en oxygène (DBO5). Les valeurs de la DBO5 des rivières de Bukavu varient d’une rivière à l’autre dont la moyenne est comprise entre 620 mg/L et 1063 mg/L. Les valeurs moyennes de DCO varient entre 517 mg/L et 1747 mg/L. Ces valeurs de DCO et DBO5 sont très largement supérieures à la norme, qui indique une forte pollution car les résultats sont loin de la situation critique. Le débit a été mesuré systématiquement, ce qui a permis d’évaluer la charge polluante déversée dans le lac Kivu soit de 0,195 à 9,899 kg/j de DBO, de 0,393 à 22,581 kg/j de DCO, de 0,0045 à 0,3217 kg/j d’azote et 0,00015 à 0,0422 kg/j de phosphore. Une grande partie de matière organique est non biodégradable dans la rivière Wesha suite au rapport DCO/DBO5 = 2,4. Néanmoins, pour les restes des rivières leurs matières organiques sont biodégradables, ce qui indique que les rivières sont capables de se dépolluer pourvu que la quantité de décharges soit réduite. Pour la rivière Wesha il faudra investiguer la source de la pollution.Mots-clés: charge polluante, eaux usées ménagères, rivières, Bukavu, lac Kivu. Assessment of the charge polluting of the rivers, wast domestic flowing waters and vain streaning in the Bukavu city south kivu, Democratic Republic of Congo The present survey is about the assessment of the pollution load of the rivers in the city of Bukavu. The parameters of pollution, measured in this survey are the chemical demand in oxygen (DCO), the total nitrogen and the total phosphor, and the biochemical demand in oxygen (DBO5). The values of the DBO5 of the rivers of Bukavu vary from a river to the one of whose average is consisted between 620 mg/L and 1063 mg/L. The middle values of DCO vary between 517 mg/L and 1747 mg/L. These values of DCO and DBO5 are very extensively superior to the norm, which indicates a strong pollution because the results are far from the critical situation. The flow has been measured systematically, what permitted to value the pollution load poured in the Kivu lake is from 0,195 to 9,899 kg/j of DBO, of 0,393 to 22,581 kg/j of DCO, of 0,0045 to 0,3217 kg/j of nitrogen and 0,00015 to 0,0422 kg/j of phosphor. A big part of organic matter is non-biodegradable in the Wesha river following the DCO/DBO5 report = 2,4. Nevertheless, for the rests of the rivers their organic matters are biodegradable, what indicates that the rivers are capable of himself depolluted so long as the quantity of discharges is reduced. For the Wesha river it will need to study the source of the pollution.Keywords: pollution load, waters worn-out housewives, rivers, Bukavu, lake Kivu

Artemisia Spp. Derivatives for COVID-19 Treatment: Anecdotal Use, Political Hype, Treatment Potential, Challenges, and Road Map to Randomized Clinical Trials

The world is currently facing a novel COVID-19 pandemic caused by SARS-CoV-2 that, as of July 12, 2020, has caused a reported 12,322,395 cases and 556,335 deaths. To date, only two treatments, remdesivir and dexamethasone, have demonstrated clinical efficacy through randomized controlled trials (RCTs) in seriously ill patients. The search for new or repurposed drugs for treatment of COVID-19 continues. We have witnessed anecdotal use of herbal medicines, including Artemisia spp. extracts, in low-income countries, and exaggerated claims of their efficacies that are not evidence based, with subsequent political controversy. These events highlight the urgent need for further research on herbal compounds to evaluate efficacy through RCTs, and, when efficacious compounds are identified, to establish the active ingredients, develop formulations and dosing, and define pharmacokinetics, toxicology, and safety to enable drug development. Derivatives from the herb Artemisia annua have been used as traditional medicine over centuries for the treatment of fevers, malaria, and respiratory tract infections. We review the bioactive compounds, pharmacological and immunological effects, and traditional uses for Artemisia spp. derivatives, and discuss the challenges and controversies surrounding current efforts and the scientific road map to advance them to prevent or treat COVID-19

Molecular data show Clinostomoides Dollfus, 1950 is a junior synonym of Clinostomum Leidy, 1856, with redescription of metacercariae of Clinostomum brieni n. comb

The genus Clinostomoides Dollfus, 1950 was erected to accommodate a single worm from Ardea goliath sampled in the Belgian Congo. The specimen was distinguished from other clinostomids by its large size and posterior genitalia. In the following years, metacercariae of Clinostomoides brieni, have been described in Clarias spp. in southern and western Africa. A few authors have referred to Clinostomum brieni, but all such usages appear to be lapsus calami, and the validity of Clinostomoides remains widely accepted. In this study our aim was: position C. brieni among the growing clinostomids molecular database, and redescribe the species with emphasis on characters that have emerged as important in recent work. We sequenced two nuclear (partial 18S and ITS) and one mitochondrial marker (partial cytochrome c oxidase I) and studied morphology in metacercariae from hosts and localities likely to harbour the type species (Clarias spp., Democratic Republic of the Congo, South Africa). Phylogenetic analysis shows C. brieni belongs within Clinostomum Leidy, 1856. We therefore transfer C. brieni to Clinostomum, amend the diagnosis for the genus Clinostomum and provide a critical analysis of other species in Clinostomoides, all of which we consider species inquirendae, as they rest on comparisons of different developmental stages

Investigation of the biological activity in MSW landfills under dry climates (Tunisia and Haiti)

This paper presents the results of the investigations carried out over two years (April 2000 – February 2002) to quantify the biological activity that develops in four municipal solid waste landfills located in different regions of two dry climate countries i.e. Haiti and Tunisia. Since the climatic water balance is negative (potential evapotranspiration being 1.5 to 5 times higher than rainfall), it has often been considered that this kind of landfill has neither environmental impact nor efficient biological activity. However, after five campaigns of sampling and analysis at different seasons, the results of the investigations show a relatively stable biological activity in the four landfills with biogas often containing more than 60 percent of methane. Indeed, under the upper waste layer that was effectively dry (dry weight from 85 to 98 %), the core of refuse contained between 35 and 65 % of dry matter. In some boreholes, the produced gases periodically expelled leachates like small geysers. Therefore, the results assert that landfill management in countries with dry climate should be considered with adapted technologies, not necessary the same as under temperate or humid climates