Suivi de la qualité physico-chimique et bactériologique des eaux des cours d’eau de Ngaoundéré, au Cameroun

Dans le souci d’évaluer l’influence possible des activités anthropiques sur les eaux de surface à Ngaoundéré, des analyses des paramètres physico-chimiques et bactériologiques indicateurs de pollution ont été effectuées sur dix sept (17) points d’échantillonnage retenus en fonction de leur sollicitation par les populations et leur exposition aux sources probables de pollution. Les paramètres physico-chimiques (température, pH, conductivité, turbidité, matière organique en suspension, oxydabilité au permanganate de potassium, fer, bicarbonates, nitrates, phosphates et ammonium) et bactériologiques (streptocoques fécaux et vibrions) ont été analysés et comparés aux normes internationales. Les résultats montrent des fortes concentrations en matière organique (9,30 à 10,56 mgO<sub>2</sub>/L), Fer (1,69 à 5,57 mg/L), Phosphates (1,73 à 3,09 mg/L), ammonium (1,78 à 2,19 mg/L) et une de turbidité 63,32 à 64,05 NTU dans ces eaux. En plus ces eaux hébergent d’importantes communautés microbiennes parmi lesquelles les streptocoques fécaux et les vibrions. Les teneurs de ces polluants diffèrent d’un point à un autre et selon la période de prélèvement. Une approche statistique multi-variée des résultats montre que l’activité anthropique reste la source majeure des rejets polluants dans les eaux.Mots-clés: pollution, physico-chimie, bactériologie, eaux de surface, Ngaoundéré, Cameroun. Survey of physico-chemical and bacteriological quality of water along the Ngaoundere stream (Cameroon)To evaluate the possible influence of human activities and nature on Ngaoundere stream, some physicochemical and bacteriological pollution indicators were analyses carried out on 17 sites selected on the basis of their probable exposure to pollution. Physicochemical parameters (temperature, pH, conductivity, turbidity, suspended matter, organic matter, iron, bicarbonates, nitrogen, phosphates and ammonium) and bacteriological parameters (fecal streptococcus and vibrio) were determined and compared to international standards.  Results obtained showed a high concentration in organic matter (9.30 to 10.56 mgO<sub>2</sub>/L), iron (1.69 to 5.57 mg/L), phosphates (1.73 to 3.09 mg/L), ammonium (1.78 to 2.19 mg/L) and turbidity of 63.32 to 64.05 NTU. The presence of high quantities of test micro-organisms was noted in these water samples, that is fecal streptococcus and vibrio. The levels of these pollutants in the different water samples varied from one site to another and with sampling period. A multivariate statistical approach demonstrated that human activities remained the major sources of pollutants in surface water.Keywords: pollution, physicochemical, bacteriological, surface water, Ngaoundere, Cameroon

Toxicologic screening of fungi isolated from millet (pennisetum spp) during the rainy and dry harmattan seasons in Niger state, Nigeria

A survey of fungi contaminating mouldy field, stored and marketed millet samples collected during rainy and dry harmattan seasons of the year 2000 from the twenty five local government areas of NigerState, Nigeria, was conducted. Some of the fungal isolates from the two groups of samples were screened for their mycotoxin producing potentials in mice. Aflatoxin B1 content of the rainy season millet samples was determined. Aspergillus niger was the predominant fungi found in millet during the rains. Twelve out of the 49 wet season millet samples were contaminated with AFB1 at concentrations between 1370.28 and 3495.10 ug/kg. Penicillium spp. was the commonest contaminant of millet during the dry harmattan season. Thirty five of the fifty five fungal isolates screened for toxicity were found to produce toxic metabolites that were lethal to mice and were isolates of Aspergillus, Fusarium, Penicillium, Rhizopus, Mucor, Syncephalastrum, and Helminthosporium

Strategi Kepala Sekolah dalam Mengelola Konflik Menyikapi Dampak Negatif Penerapan Full Day School

This study tried to describe the principal in managing conflict of the application negative impact of the implementation of the Full Day School this research was conducted using qualitative approach with a phenomenological method. These results indicate that the principal can perform a variety of strategies to fix conflict so as not to interfere with the performance of teachers, child's comfort, and confidence of parents.Penelitian ini mencoba mendeskripsikan tentang kepala sekolah dalam melakukan strategi pegelolaan konflik menyikapi dampak negatif dari penerapan Full Day School. Penelitian ini dilakukan dengan menggunakan pendekatan kualitatif dengan metode fenomenologi. Hasil penelitian ini menunjukkan bahwa kepala sekolah dapat melakukan berbagai strategi guna menyelesaikan konflik sehingga tidak menggangu kinerja guru, Kenyamanan anak, dan kepercayaan orangtua

Effect of akyl chain length, flow, and temperature on the corrosion inhibition of carbon steel in a simulated acidizing environment by an imidazoline-based inhibitor

An imidazoline, 2-heptadecyl-1-[2-(octadecanoylamino)ethyl]-2- imidazoline (QSI) with -C17H35 as the tail chain length was synthesized, characterized, and studied as corrosion inhibitor for low carbon steel in 15% HCl solution under static and hydrodynamic conditions. Influence of addition of KI, temperature, and chain length of pendant hydrocarbon on inhibition efficiency (η) was also examined. It is found that, QSI exhibits a mixed type behavior but fairly inhibited the corrosion of low carbon steel in the studied medium. The maximum concentration studied (400 mg/L) afforded η of <50%. Addition of KI to QSI synergistically enhanced the corrosion inhibition performance of QSI, upgrading the η to approximately 90%. Increase in the system temperature increases the η of both QSI and QSI + KI. From the variation of η with temperature and the calculated corrosion kinetic parameters, chemical adsorption is proposed as the adsorption mechanism of the additives. QSI performs better under hydrodynamic condition than static condition. However, the corrosion resistance of the metal decreases at rotation speed higher than 1000 rpm. Inhibition efficiency of imidazoline decreases as the length of the hydrocarbon pendant chain increases. Imidazoline compounds with -C13H27 and - C15H31 as the length of the pendant group hydrocarbon perform better than QSI with -C17H35

Penumbra Aspiration Thrombectomy of the Superior Mesenteric Artery for Mesenteric Ischemia

Acute mesenteric ischemia from thromboembolic occlusion is a life-threatening emergency associated with a high mortality rate. Prompt diagnosis and intervention are vital to preserve viable bowel and prevent mortality. In the past decade, a shift has occurred toward minimally invasive alternatives such as endovascular therapies. We present a case of acute mesenteric ischemia from superior mesenteric artery thrombosis treated promptly with the Penumbra suction thrombectomy device (Penumbra Inc)

First report on natural Leishmania infection of Phlebotomus sergenti due Leishmania tropica by high resolution melting curve method in Southeastern Iran

Objective: To identify the Leishmania species in infected sand flies by Real-time PCR coupled with HRM analysis. Methods: Real-time PCR coupled with HRM analysis targeting the first iidnetenrtnifayl atrnadn sdcirsitbinegdu sispha cLeeri s(hITmSa1n) ioaf snpueccleieasr irnib soasnodm aflli eDsN sAp eacsi mtheen sg.e Rneetsiuc ltms:a rTkherre we aosu tu soef d1 1to5 females of Phlebotomus sergenti (P. sergenti) (2.6%) were positive to Leishmania tropica (L. tropica). Conclusions: This is the first report on P. sergenti as the main and proven vector of anthroponitic cutaneous leishmaniasis in Dehbakri County using Real-time PCR coupled with HRM analysis. Tidheias l mfoert hlaordg eis s craapleid g,e sneontsyiptiivneg apnrodj escptesc.ifi

Original Article

Abstract Background: Mosquitoes transmit several diseases to human. There are several measures for control of larvae. As part of Integrated Vector Management (IVM) program, the utility of floating layers of polystyrene beads (EPS) is a potential alternative in habitats of mosquito larva. EPS beads prevent oviposition of mosquito as well as killing the immature stages by forming a tick layer on the water surface. They are cheap, environmentally safe and do not need frequent application and remain on the surface of water for long time. The objective of the current study was to asses the effectiveness of two types of polystyrene beads of (EPS) and (SWAP) for control of mosquito larvae under laboratory conditions. Methods: Anopheles stephensi and Culex quinquefasciatus were used for experimental purposes. In each tray 250 larvae of late 3 rd and early 4 th instars were introduced. The experiment was conducted on 4 replicates for An. stephensi, Cu. quinquefasciatus and combination of both. Emerging of adult mosquitoes were calculated every day until the end of experiments. Results: Mortality rate and Inhibition of Emerge (IE) for Cu. quinquefasciatus, An. stephensi and combination of both species was 97.8%, 100% and 99.07%, respectively using EPS. In average, EPS was able to kill 98.9% of larvae. The figures with SWAP were 63%, 91.05% and 72.65%, respectively. The average mortality for mosquitoes was 75.57% Conclusion: EPS and SWAP beads can be very effective and practical for elimination of An. stephensi and Cx. quinquefasciatus under the laboratory conditions

Phylogenomics revealed migration routes and adaptive radiation timing of holarctic malaria mosquito species of the Maculipennis group

BackgroundPhylogenetic analyses of closely related species of mosquitoes are important for better understanding the evolution of traits contributing to transmission of vector-borne diseases. Six out of 41 dominant malaria vectors of the genus Anopheles in the world belong to the Maculipennis Group, which is subdivided into two Nearctic subgroups (Freeborni and Quadrimaculatus) and one Palearctic (Maculipennis) subgroup. Although previous studies considered the Nearctic subgroups as ancestral, details about their relationship with the Palearctic subgroup, and their migration times and routes from North America to Eurasia remain controversial. The Palearctic species An. beklemishevi is currently included in the Nearctic Quadrimaculatus subgroup adding to the uncertainties in mosquito systematics.ResultsTo reconstruct historic relationships in the Maculipennis Group, we conducted a phylogenomic analysis of 11 Palearctic and 2 Nearctic species based on sequences of 1271 orthologous genes. The analysis indicated that the Palearctic species An. beklemishevi clusters together with other Eurasian species and represents a basal lineage among them. Also, An. beklemishevi is related more closely to An. freeborni, which inhabits the Western United States, rather than to An. quadrimaculatus, a species from the Eastern United States. The time-calibrated tree suggests a migration of mosquitoes in the Maculipennis Group from North America to Eurasia about 20-25 million years ago through the Bering Land Bridge. A Hybridcheck analysis demonstrated highly significant signatures of introgression events between allopatric species An. labranchiae and An. beklemishevi. The analysis also identified ancestral introgression events between An. sacharovi and its Nearctic relative An. freeborni despite their current geographic isolation. The reconstructed phylogeny suggests that vector competence and the ability to enter complete diapause during winter evolved independently in different lineages of the Maculipennis Group.ConclusionsOur phylogenomic analyses reveal migration routes and adaptive radiation timing of Holarctic malaria vectors and strongly support the inclusion of An. beklemishevi into the Maculipennis Subgroup. Detailed knowledge of the evolutionary history of the Maculipennis Subgroup provides a framework for examining the genomic changes related to ecological adaptation and susceptibility to human pathogens. These genomic variations may inform researchers about similar changes in the future providing insights into the patterns of disease transmission in Eurasia

Comparative performance of imagicides on Anopheles stephensi, main malaria vector in a malarious area, southern Iran

Abstract Background &amp; objectives: Jiroft district has subtropical climate and prone to seasonal malaria transmission with annual parasite index (API) 4.2 per 1000 in 2006. Anopheles stephensi Liston is a dominant malaria vector. The monitoring of insecticide susceptibility and irritability was conducted using discriminative dose as described by WHO

Cysteine dependence of Lactobacillus iners is a potential therapeutic target for vaginal microbiota modulation

Vaginal microbiota composition affects many facets of reproductive health. Lactobacillus iners-dominated microbial communities are associated with poorer outcomes, including higher risk of bacterial vaginosis (BV), compared with vaginal microbiota rich in L. crispatus. Unfortunately, standard-of-care metronidazole therapy for BV typically results in dominance of L. iners, probably contributing to post-treatment relapse. Here we generate an L. iners isolate collection comprising 34 previously unreported isolates from 14 South African women with and without BV and 4 previously unreported isolates from 3 US women. We also report an associated genome catalogue comprising 1,218 vaginal Lactobacillus isolate genomes and metagenome-assembled genomes from >300 women across 4 continents. We show that, unlike L. crispatus, L. iners growth is dependent on L-cysteine in vitro and we trace this phenotype to the absence of canonical cysteine biosynthesis pathways and a restricted repertoire of cysteine-related transport mechanisms. We further show that cysteine concentrations in cervicovaginal lavage samples correlate with Lactobacillus abundance in vivo and that cystine uptake inhibitors selectively inhibit L. iners growth in vitro. Combining an inhibitor with metronidazole promotes L. crispatus dominance of defined BV-like communities in vitro by suppressing L. iners growth. Our findings enable a better understanding of L. iners biology and suggest candidate treatments to modulate the vaginal microbiota to improve reproductive health for women globally