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Study region: The Upper Athi River Basin (Lat: 1°25′17.61°S and Long: 37°15′29.55°E) in Kenya, East Africa. Study focus: The effects of land use/land cover type on suspended sediment concentrations and yield were investigated in the upper Athi river basin in Kenya. The suspended sediment concentrations and yield, river discharges, water levels and flow velocities were monitored in stations established at the outlets of sub-basins and also at the outlet of the main basin in period 2012–2015. New hydrological insights: The magnitude of river discharge in the upper Athi river basin is not only a function of the magnitude of rainfall, but combination of land uses/land covers determined the magnitude of sediment yield in the sub-basins. The highest sediment yield occurred in a semi-arid sub-basin dominated by savannah grassland and livestock grazing. The lowest occurred in the high rainfall sub-basins dominated by forest with mixed farming and settlements. Significant sediment transport commenced at an effective river discharge of 405 m3s−1 which is a frequent discharge event resulting in significant sediment load transport in most rainy seasons and years. The magnitude of suspended sediment discharge is a function of the magnitude of rainfall such that the greatest sediment transport occurs during the long rainy seasons (54%) as compared to 41% during the short rainy season. The total annual suspended sediment load in the basin ranged 2.11–3.77 × 106 tons.yr−1 and sediment production rate ranged 205–366 tons.km−2.year−1.

Study region: This study was undertaken in the Athi-Sabaki river basin in Kenya in East Africa. Study focus: The study focused on the determination of the influence of streamflow variability on salt fluxes. This involved monitoring of river discharge and river salinity in the period between 2012 and 2018. New hydrological insights: : This study demonstrates that Athi-Sabaki river discharges significant quantity of salt to the sea. There are significant seasonal and inter-annual variations in salt fluxes that are due to variations in river discharge and rainfall in the basin. The relationship between streamflow variations and variations of salinity in the river was inverse with highest salinity concentrations and fluxes occurring during low flow conditions. The river salinity and TDS concentrations decreased with an increase in river discharge due to dilution effect and flushing of salt from the river. The highly polluted sub-basins draining through the City of Nairobi exhibited relatively higher salinity and salt fluxes as compared to non-polluted ones draining rural areas. The total salt flux in the basin ranged between 29 × 103 and 261 × 103 tons year−1. The relatively high salinity and salt fluxes were attributed to the discharge of wastewaters, seepage of groundwater and irrigation return flows. The study calls for water pollution control, sustainable irrigation and landuse practices in the basin. Keywords: Athi-Sabaki river, Streamflow variations, Salinity variations, Water pollution, Salt fluxes, Kenya

This review provides an overview of recent theoretical and empirical developments regarding psychosocial factors related to the prediction and prevention of sport injuries, and highlights some of the most interesting areas of investigation that have been carried out in the past few years. For instance, a systematic review of the most cited and used theoretical framework in the field has recently been performed, which supports the model's suggestion that psychosocial variables, as well as psychologically based interventions, can influence injury risk among athletes. Based on substantial empirical evidence it is also shown that changes in stress and perceived recovery appear to predict injury occurrence in sport. Current studies, focusing on overuse injuries, also suggest that cultural norms and rules can be seen as factors that can indirectly influence the risk of becoming injured. Future research directions are presented such as the need for interdisciplinary injury prevention programs based on a combination of physiological and psychological interventions., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Increased concentrations of C3dg were demonstrated in plasma from patients with primary biliary cirrhosis (PBC), indicating in vivo activation of C3. Rapid spontaneous C3 cleavage by the classical pathway was observed in vitro in serum and in EDTA plasma reconstituted with Ca++ and Mg++, suggesting the presence of complement-activating substances. On incubation with fresh normal serum, purified polyclonal IgM from patients with PBC induced C1 activation, C4 cleavage, and C3dg formation. No C3 cleavage was observed when PBC-IgM was incubated with a C2-deficient serum. We suggest that the complement activation in vivo in PBC, which occurs predominantly by the classical pathway and is characterized by increased concentrations of C1 activation complexes, decreased C4 concentrations, and hypercatabolism of C3, is attributable to an abnormal IgM population.