815 research outputs found
AL 3 (BH 261): a new globular cluster in the Galaxy
AL~3 (BH 261), previously classified as a faint open cluster candidate, is
shown to be a new globular cluster in the Milky Way, by means of B, V and I
Color-Magnitude Diagrams. The main feature of AL~3 is a prominent blue extended
Horizontal Branch. Its Color-Magnitude Diagrams match those of the intermediate
metallicity cluster M~5. The cluster is projected in a rich bulge field, also
contaminated by the disk main sequence. The globular cluster is located in the
Galactic bulge at a distance from the Sun d = 6.00.5 kpc. The
reddening is E(B-V)=0.360.03 and the metallicity is estimated to be [Fe/H]
-1.30.25. AL~3 is probably one of the least massive globular
clusters of the Galaxy.Comment: 6 figures. Astrophysical Journal Letters, in pres
Diet and exercise:a match made in bone
Purpose of Review: Multiple dietary components have the potential to positively affect bone mineral density in early life and reduce loss of bone mass with aging. In addition, regular weight-bearing physical activity has a strong positive effect on bone through activation of osteocyte signaling. We will explore possible synergistic effects of dietary components and mechanical stimuli for bone health by identifying dietary components that have the potential to alter the response of osteocytes to mechanical loading. Recent Findings: Several (sub)cellular aspects of osteocytes determine their signaling towards osteoblasts and osteoclasts in response to mechanical stimuli, such as the osteocyte cytoskeleton, estrogen receptor α, the vitamin D receptor, and the architecture of the lacunocanalicular system. Potential modulators of these features include 1,25-dihydroxy vitamin D3, several forms of vitamin K, and the phytoestrogen genistein. Summary: Multiple dietary components potentially affect osteocyte function and therefore may have a synergistic effect on bone health when combined with a regime of physical activity
Reaming debris as a novel source of autologous bone to enhance healing of bone defects
Item does not contain fulltextReaming debris is formed when bone defects are stabilized with an intramedullary nail, and contains viable osteoblast-like cells and growth factors, and might thus act as a natural osteoinductive scaffold. The advantage of using reaming debris over stem cells or autologous bone for healing bone defects is that no extra surgery is needed to obtain the material. To assess the clinical feasibility of using reaming debris to enhance bone healing, we investigated whether reaming debris enhances the healing rate of a bone defect in sheep tibia, compared to an empty gap. As golden standard the defect was filled with iliac crest bone. Bones treated with iliac crest bone and reaming debris showed larger callus volume, increased bone volume, and decreased cartilage volume in the fracture gap, and increased torsional toughness compared to the empty gap group at 3 weeks postoperative. In addition, bones treated with reaming debris showed increased torsional stiffness at 6 weeks postoperatively compared to the empty defect group, while bending stiffness was marginally increased. These results indicate that reaming debris could serve as an excellent alternative to iliac crest bone for speeding up the healing process in bone defects that are treated with an intramedullary nail
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