The snow must go on: Ground ice encasement, snow compaction and absence of snow differently cause soil hypoxia, CO2 accumulation and tree seedling damage in boreal forest

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Influence of dietary taurine on vitamin D absorption

To evaluate the influence of dietary taurine supplementation on vitamin D absorption, we studied three groups of infants: 21 (11 preterm) were fed a taurine-free formula, 21 (10 preterm) were fed a taurine-supplemented formula (50 mg/100 g of powder) and 20 (9 preterm) were fed human, not heat-treated milk. Taurine, total bile acids, glyco-(GBA) and tauro-(TBA) conjugated bile acids, 25-hydroxyvitamin D3 (25OHD3) and 1,25-dihydroxyvitamin D3 (1,25OH2D3) were determined in all infants at birth in blood cord and at one and three months of life. In preterm infants fed a taurine-free formula, we found lower plasma taurine levels than in infants of other groups at one and three months of life. In these infants, GBA predominated, with a G/T ratio of 1.1 and 1.4 at one and three months of life, whereas in all other infants TBA predominated with a G/T ratio always < 1. Also, 25OHD3 and 1,25OH2D3 levels were significantly lower in preterm infants fed a taurine-free formula than in infants fed a taurine-enriched formula or human milk. Term infants fed a taurine-free formula did not show differences in the parameters studied in comparison to infants of other groups. Low taurine dietary intake appears to compromise vitamin D absorption in preterm infants, and therefore taurine supplementation of preterm infant formulas should be encouraged

Dew point effect of cooled hydrogel pads on human stratum corneum biosurface.

BACKGROUND: Cooled hydrogel pads are used to prevent overheating effects of laser therapy. They do not induce cold injuries to the skin, but their more subtle physiological effects have not been thoroughly studied. PURPOSE: To describe the changes in transepidermal water loss and electrometric properties of the skin surface following application of cooled hydrogel pads. Measurements were performed on normal forearm skin of 27 healthy volunteers and on freshly excised skin from abdominoplasty. METHODS: LaserAid hydrogel pads cooled to 4 degrees C were placed for 15 min on the forearm skin. Measurements of transepidermal water loss (TEWL) and electrometric properties (Corneometer, Nova DPM 900) were performed before application and after removal of the cooled pads. RESULTS: A consistent increase in corneometer units, dermal phase meter (DPM) values and TEWL were recorded at removal of the cooled hydrogel pads. Both the in vivo and in vitro assessments brought similar information. DISCUSSION: The similar changes disclosed in vitro and in vivo suggest that a common physical process is operating in these conditions. The observed phenomenon is opposite to the predicted events given by the Arrhenius law probably because of the combination of cooling and occlusion by the pads. A dew point effect (air temperature at which relative humidity is maximal) is likely involved in the moisture content of the stratum corneum. Thus, the biological impact of using cooling hydrogel pads during laser therapy is different from the effect of a cryogenic spray cooling procedure. The better preservation of the water balance in the stratum corneum by the cooled hydrogel pads could have a beneficial esthetic effect on laser treated areas