Optimizing grain yields reduces CH4 emissions from rice paddy fields.

Microbial production in anoxic wetland rice soils is a major source of atmospheric CH4 the most important non-CO2 greenhouse gas. Much higher CH4 emissions from well managed irrigated rice fields in the wet than in the dry season could not be explained by seasonal differences in temperature. We hypothesized that high CH4 emissions in the wet season are caused by low grain to biomass ratios. In a screenhouse experiment, removing spikelets to reduce the plants' capacity to store photosynthetically fixed C in grains increased CH4 emissions, presumably via extra C inputs to the soil. Unfavorable conditions for spikelet formation in the wet season may similarly explain high methane emissions. The observed relationship between reduced grain filling and CH4 emission provides opportunities to mitigate CH4 emissions by optimizing rice productivity.

Fluxes and pools of methane in wetland rice soils with varying organic inputs.

Measurements of methane emission rates and concentrations in the soil were made during four growing seasons at the International Rice Research Institute in the Philippines, on plots receiving different levels of organic input. Fluxes were measured using the automated closed chambers system (total emission) and small chambers installed between plants (water surface flux). Concentrations of methane in the soil were measured by collecting soil cores including the gas phase (soil-entrapped methane) and by sampling soil solution in situ (dissolved methane). There was much variability between seasons, but total fluxes from plots receiving high organic inputs (16-24 g CH4 m(-2)) always exceeded those from the low input plots (3-9 g CH4 m(-2)). The fraction of the total emission emerging from the surface water (presumably dominated by ebullition) was greater during the first part of the season, and greater from the high organic input plots (35-62%) than from the low input plots (15-23%). Concentrations of dissolved and entrapped methane in the low organic input plots increased gradually throughout the season; in the high input plots there was an early-season peak which was also seen in emissions. On both treatments, periods of high methane concentrations in the soil coincided with high rates of water surface flux whereas low concentrations of methane were generally associated with low flux rates.

[Fatty emulsions in parenteral feeding following liver transplantation. A study of the neurotropic effect of MCT/LCT emulsions using EEG]. / Fettemulsionen in der parenteralen Ernährung nach Lebertransplantation. Eine Untersuchung zur neurotropen Wirkung von MCT/LCT-Emulsionen mittels EEG.

In the early postoperative period after liver transplantation a possible neurotropic side effect of middle-chain triglycerides used for total parenteral nutrition (TPN) was evaluated by EEG and Glasgow Coma Scale. Group I: no fat for TPN; Group II: 0.7 g/kg body weight (BW) and day, of MCT/LCT emulsion; Group III: 1.5 g/kg BW and day, of MCT/LCT emulsion. Only on postoperative day 5/6 significant differences in distribution of background activity in the EEG were seen between Group I and II. Patients in Group I showed more pathological EEG patterns (Mann-Whitney-U-test p less than 0.05). Per discriminant analysis an influence of applicated fatty acids on the registered background activity could be excluded. Instead an underlying rejection of the graft in 7 of 10 patients could be made responsible for deterioration of the EEG pattern. Following the presented data a negative neurotropic effect of MCT/LCT emulsions in the described dosages can be negated.

Fat emulsions in parenteral nutrition after liver transplantation: The recovery of the allografts RES function and histological observations.

Following liver transplantation, the effect of post-operative parenteral nutrition with MCT LCT (Medium Chain Triglycerides/Long Chain Triglycerides) fat emulsions on the recovery of allografts RES function was investigated in a randomised prospective study of three groups of patients (group I, n = 14: 50g MCT LCT fats twice weekly, group II, n = 15: 0.7 g/kg body weight per day MCT LCT fats, group III, n = 17: 1.5 g/kg body weight per day MCT LCT fats). RES function was assessed using the (99m)Tc-HSA-MM-Clearance ((99m)Technitium-Human serum albumen-Millimicrosphere-Clearance). There were no statistically significant differences in the recovery of RES function between the groups. A negative effect on RES function as a result of the administration of MCT LCT fat emulsions up to 1.5 g/kg b.w. per day can therefore be excluded. The evaluation of liver biopsies before the administration of fats and at the end of TPN (Total Parenteral Nutrition) showed no evidence, in the 20 patients investigated, of any fatty changes in the liver caused by the infusion of fat.

[Fat emulsions in parenteral feeding following liver transplantation. I. Effect on the recovery of RES function in the transplant]. / Fettemulsionen in der parenteralen Ernährung nach Lebertransplantation. I. Einfluss auf die Erholung der RES-Funktion im Transplantat.

Following liver transplantation, the effect of postoperative parenteral nutrition with MCT/LCT fatty emulsions on the recovery of RES function in the allograft was investigated in a randomised prospective study of three groups of patients (group I: 50 g MCT/LCT fats twice weekly, group II: 0.7 g/kg body weight per day MCT/LCT fats, group III: 1.5 g/kg body weight per day MCT/LCT fats). RES function was assessed using 99mTc-HSA-MM clearance. There were no statistically significant differences in the recovery of RES function after transplantation between the three groups. A negative effect on RES function as a result of the administration of MCT/LCT fats up to 1.5 g/kg body weight per day can therefore be excluded.