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BACKGROUND Hyperphosphatemia, hypocalcemia, and elevation of parathyroid hormone (PTH) are typical abnormalities of uremic patients with Secondary hyperparathyroidism (SHPT). However, metabolic imbalance associated with SHPT is not well understood. METHODS A total of 15 SHPT patients with an intact parathyroid hormone (iPTH) level > 600 pg/mL were set as preoperative (PR) group, 15 age- and gender-matched controls who had undergone parathyroidectomy plus forearm transplantation because of hyperparathyroidism and achieved an iPTH level

The use of catalytic distillation (CD) in chemical production has gained popularity in recent years, as it results in minimized installation costs and increased efficiency. However, the design of suitable modular catalytic structured packing (MCSP) for CD processes remains a challenge. This paper presents a novel MCSP named Winpak-C. The hydraulic performance of Winpak-C is investigated in a 400-mm diameter column with an air-water system. Predictive models for the pressure drop and liquid holdup are proposed, which provide reasonably close predictions. The models describe the gas loading point, which reflects the transition from the liquid loading regime to the unstable flooding regime. Further, a visual experiment is performed to determine the maximum liquid load of the catalyst-containing bags, and the flow behaviours around the liquid load point are described. In addition, a tracer method is employed to determine the liquid residence time distribution (RTD). The Peclet number and axial dispersion coefficient deduced from RTD curves are discussed and compared with those for traditional MCSP. This study on the hydraulics of Winpak-C is significant for the design and scale-up of CD processes.