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The potential for top-down control of phytoplankton populations by zooplankton in tropical lentic systems was examined in 12 shallow reservoirs using a 15 year data set. Regression analyses showed that calanoid, cyclopoid, and rotifer, but not cladoceran, abundances were important in infl uencing the structure of phytoplankton communities. Counts of chlorophytes Ankistrodesmus, Cosmarium and Peridinium decreased with increasing calanoid, cyclopoid and rotifi er numbers while populations of the diatoms Melosira and Synedra, Planktotrix and Scenedesmus were inversely correlated with the abundance of calanoid copepods. Cyanobacteria populations, with the exception of Planktotrix, were not negatively affected by increasing zooplankton numbers. This study supports the hypothesis that zooplankton exert 'top-down' control on certain algal communities in tropical lentic systems, however, the use of broad taxonomic groups (calanoids, cyclopoids, cladocerans, and rotifers) potentially masks information on how specifi c zooplankton exert control on phytoplankton communities. We suggest that a greater taxonomic resolution of the zooplankton fauna is necessary to further understand the complex associations between phytoplankton and zooplankton communities within tropical reservoirs. Nevertheless, even at this coarse scale of investigation, this paper presents clear trends that support the importance of zooplankton in the control of freshwater algal abundance. [ABSTRACT FROM AUTHOR]

Peritoneal dialysis (PD) is the only well-established home-based dialysis therapy in Singapore. As it is a home-based modality, PD should be considered as a preferred mode of kidney replacement therapy (KRT) for patients with kidney failure during this COVID-19 pandemic as it avoids frequent visits to hospitals and/or satellite dialysis centres. The highly infectious nature of this virus has led to the implementation of the Disease Outbreak Response System Condition orange status in Singapore since early February 2020. This paper summarises the strategies for management of several aspects of PD in Singapore during this COVID-19 pandemic, including PD catheter insertion, PD training, home visit and assisted PD, outpatient PD clinic, inpatient management of PD patients with or without COVID-19 infection, PD as KRT for COVID-19 patients with acute kidney injury, management of common complications in PD (peritonitis and fluid overload), and management of PD inventory.