Considering Soil Potassium Pools with Dissimilar Plant Availability

Soil potassium (K) has traditionally been portrayed as residing in four functional pools: solution K, exchangeable K, interlayer (sometimes referred to as “fixed” or “nonexchangeable”) K, and structural K in primary minerals. However, this four-pool model and associated terminology have created confusion in understanding the dynamics of K supply to plants and the fate of K returned to the soil in fertilizers, residues, or waste products. This chapter presents an alternative framework to depict soil K pools. The framework distinguishes between micas and feldspars as K-bearing primary minerals, based on the presence of K in interlayer positions or three-dimensional framework structures, respectively; identifies a pool of K in neoformed secondary minerals that can include fertilizer reaction products; and replaces the “exchangeable” K pool with a pool defined as “surface-adsorbed” K, identifying where the K is located and the mechanism by which it is held rather than identification based on particular soil testing procedures. In this chapter, we discuss these K pools and their behavior in relation to plant K acquisition and soil K dynamics

Critical care polyneuropathy in burn injuries: An integrative review

Polyneuropathy is a debilitating condition which may be associated with large burns. The aim of this integrative review is to identify factors that contribute to the development of critical care polyneuropathy in patients admitted to an intensive care unit with a severe burn injury. PubMed, Scopus, CINHAL and EMBASE were searched up until July 2016. Studies/case reports focusing on critical care polyneuropathy for burn injured patients were included. The ten studies, included a total of 2755 burns subjects and identified 128 critical care polyneuropathy patients with an incidence of 4.4%. Three case reports identified prolonged ventilation and development of critical care neuropathy. Overall, factors identified as contributing to the development of critical care polyneuropathy in burn injured patients included prolonged ventilation (>7 days), large and deep total body surface area burns (mean TBSA 40%), and sepsis. Critical care polyneuropathy in burn patients remains challenging to diagnose and treat. To date, there is a lack of long term studies describing the impact of critical care polyneuropathy on functional performance or participation in activities of daily living in the burns population and this is consistent with the general literature addressing the lack of follow up assessments and long term consequences of persistent muscle weakness