Feasibility of using phase change materials to control the heat of hydration in massive concrete structures.

This paper presents experimental results that can be applied to select a possible phase change material (PCM), such as a latent heat material (LHM), to control the hydration heat in mass concrete structures. Five experimental tests (microconduction, simplified adiabatic temperature rise, heat, and compressive strength tests) were conducted to select the most desirable LHM out of seven types of inorganic PCM used in cement mortar and to determine the most suitable mix design. The results of these experimental tests were used to assess the feasibility of using PCM to reduce hydration heat in mass concrete that was examined. The experimental results show that cement mortar containing barium- [Ba(OH)2 · 8H2O] based PCM has the lowest amount of total hydration heat of the cement pastes. The barium-based PCM provides good latent heat properties that help to prevent volume change and microcracks caused by thermal stress in mass concrete.

Gardenia jasminoides protects against cerulein-induced acute pancreatitis.

AIM: To investigate the effect of Gardenia jasminoides (GJ) on cerulein-induced acute pancreatitis (AP) in mice. METHODS: C57BL/6 mice weighing 18-20 g were divided into three groups. (1) Normal saline-treated group, (2) treatment with GJ at a dose of 0.1 g/kg, (3) treatment with GJ at a dose of 1 g/kg. GJ was administered orally (n = 6 per group) for 1 wk. Three hours later, the mice were given an intraperitoneal injection of cerulein (50 microg/kg), a stable cholecystokinin (CCK) analogue, every hour for a total of 6 h as described previously. The mice were sacrificed at 6 h after completion of cerulein injections. Blood samples were obtained to determine serum amylase, lipase and cytokine levels. The pancreas was rapidly removed for morphologic examination and scoring. A portion of pancreas was stored at -70 degree and prepared for the measurement of tissue myeloperoxidase (MPO) activity, an indicator of neutrophil sequestration, and for reverse-transcriptase PCR (RT-PCR) and real-time PCR measurements. RESULTS: Treatment with GJ decreased significantly the severity of pancreatitis and pancreatitis-associated lung injury. Treatment with GJ attenuated the severity of AP compared with saline-treated mice, as shown by reduction in pancreatic edema, neutrophil infiltration, serum amylase and lipase levels, serum cytokine levels, and mRNA expression of multiple inflammatory mediators. CONCLUSION: These results suggest that GJ attenuated the severity of AP as well as pancreatitis-associated lung injury.