Runners with an elevated bone turnover buy GDC-0941 (EBT) (n = 13) had a lower body mass, fewer menstrual cycles in the past year, lower estradiol and 25-hydroxycholecalciferol
concentrations, and a higher prevalence of body mass index <10% for age, vitamin D insufficiency, amenorrhea, and low bone mass. Girls with EBT consumed less than the recommended amounts of energy and had a higher prevalence of consuming <1300 mg Ca than did those with normal bone turnover.
Conclusions: Runners with EBT had a profile consistent with energy deficiency. Nutritional support to increase energy, calcium intake, and 25-hydroxycholecalciferol concentrations may improve bone mineral accrual in young runners with EBT. This trial was registered at clinicaltrials.gov as NCT01059968. Am J Clin Nutr 2010;92:652-9.”
“Percolation phenomena in bionanocomposites composed of the bioplastic polylactide and surface decorated supramolecular multiwalled carbon nanotubes (MWCNTs) are investigated. MWCNTs GSK2879552 manufacturer with three distinct surface chemistries-a native surface, a hydroxyl functionalized surface, and a short hydrocarbon functionalized surface-are prepared
and studied. Two experimental methods are used to determine percolation thresholds; melt rheology provides a measure of the mechanical percolation threshold and electrical impedance spectroscopy provides values of the electrical percolation threshold. The MWCNT-loading level required to obtain mechanical percolation is systematically found to be lower than the loading level needed to achieve electrical percolation. Hydroxylated MWCNTs have the highest percolation thresholds of 1.8 (mechanical) and 6.7 wt % (electrical), which is attributed to aggregation caused by hydrogen bonding. Alkane-grafted MWCNTs have lower percolation thresholds of 0.76 (mechanical) and 2.8 wt % ( electrical). see more However, untreated MWCNTs have the lowest thresholds of 0.16 (mechanical) and 1.5 wt % (electrical). The reduced percolation threshold observed upon conversion of the hydroxylated surface to the alkylated surface is attributed to morphological differences-functionalization disrupts hydrogen bonding and leads
to better nanotube dispersion. The combination of higher inherent conductivity and more favorable nanotube-polylactide interactions implies that unmodified MWCNTs are preferred to produce electrically conductive bionanocomposites. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 122: 2563-2572, 2011″
“We investigate the effect of particle size on reduction temperatures in surfactant capped fine iron oxide (Fe3O4) nanoparticles in size ranging from 7 to 3 nm using in situ high temperature X-ray diffraction (HTXRD). The 7 nm size particles are reduced to metallic alpha-Fe and FeO phase at 400 degrees C and remains stable up to 600 degrees C. On further heating, alpha-Fe phase grows at the expense of FeO and the growth process completes at 800 degrees C.