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Shuttle Radar Topography Mission (SRTM) - 3 data for Digital Elevation Model through morphometric analyses of the Sanaga, Nyong and Kelle watersheds and landform were correlated with field survey in a Geographical Information System (GIS) model in the Edea-Eseka Region in SW Cameroon; erected on Paleo-to Neoproterozoic crystallophyllian rock types, Cretaceous to Recent sedimentary formations later affected by reactivated and neotectonic faults. This study that aimed to evaluate the lithology, tectonic and climate interactions on operating processes and landform characteristics based on the morphometric parameters of watersheds. Parameters vary from one watershed to another establishing one to three controls. The density drainage (0.05–0.29), the constant of channel maintenance (3.5–19.47) and the drainage pattern; outlines the lithological, the tectonic and the climate controls of the morphology. The Bifurcation ratio (2–5.25), the mean bifurcation ratio (3.67–4.09), the relative relief ratio (0.21–0.27), the watershed slope (5.75–9.35) and the watershed deviation (105–507); highlights the lithostructural controls of the morphology; whilst the wandering ratio (1.54–2.12) individualises both, the structural and climate controls. The stream number (370–2473) and the stream length ratio (0.57–1.91), the elongation ratio (0.47–0.55), the circularity ratio (0.25–0.29), fitness ratio (0.56–0.63), dissection index (0.91–0.99), the concavity index (−0.1-0.56), the hypsometric integral (0.45–0.49) and the stepped longitudinal length profiles, establishes the dominant tectonic controls of the morphology; while the rho coefficient (0.34–0.43) and drainage texture (1.91–4.75) displays the lithological control of the morphology and; the drainage intensity (1.76–7.62) and the length overland flow (1.75–9.74) typified the climate control of the morphology. The Edea-Eseka Region uplift rejuvenates old watershed each time they evolve to equilibrium because of lithological variations, neotectonics, differential erosion and climate variations; overriding its morphology. This geodynamic and climatic control of morphometric processes in the SW Cameroon can be extended to the whole of Central Africa and in Equatorial Regions that display similar evolutions.

Adverse pregnancy outcomes place the lives of mother and new born babies in jeopardy, especially in Sub Saharan Africa. Although a well-balanced network of the pregnancy-associated hormones and lipid fractions is necessary for healthy pregnancy, the profiles of some of these biomarkers alongside those of some cytokines in relation to placental malaria (PM) and poor pregnancy outcomes are unknown. Therefore between 2013 and 2014, paired peripheral and placental blood samples were collected from 135 Cameroonian women at delivery. Parasitaemia was determined microscopically and haemoglobin levels using Coulter counter. Plasma levels of cytokines (IFN-γ, IL-1β and IL-7) and pregnancy-associated hormones (17β oestradiol and progesterone) were measured by ELISA and the levels of lipid fractions: total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and triglycerides (TG) determined by Colorimetric enzymatic methods. Parasitaemia was inversely related to parity, haemoglobin levels and birth weight (P≤0.019). While the levels of IFN-γ and cholesterol (total, HDL and LDL) were higher in peripheral plasma, those of IL-1β, 17β oestradiol, progesterone and triglyceride were higher in placental blood (P

Mt. Cameroon erupted simultaneously in March–April 1999 in two distinct places on its southwestern flank. A hawaiite (with An 83-76 plagioclase phenocrysts) and an alkali basalt (with Fo 84-80 olivine phenocrysts) have been simultaneously emitted respectively at 1 400 and 2 650 m of altitude a.s.l. The eruption of these co-magmatic lavas attests to the occurrence of a unique magmatic reservoir inside which the magma differentiation took place by crystal setting of denser mineral phases.