A pilot lifestyle intervention study: effects of an intervention using an activity monitor and Twitter on physical activity and body composition.

BACKGROUND: This pilot study aimed to examine the effects of a lifestyle intervention comprising an activity monitor and the concurrent use of Twitter, on physical activity (PA) and body composition. METHODS: Seventeen healthy volunteers (36±3 years) were randomly assigned to normal (N, N.=8) or Twitter (T, N.=9) intervention groups for six weeks. Participants in both groups wore an activity monitor but those in the T group also tweeted daily about their PA. An observer read the tweets from each participant and provided feedback. Body composition was determined using bioelectrical impedance analysis before and after the intervention. RESULTS: Significantly more daily steps and PA at an intensity of ≥3 metabolic equivalents (METs) were recorded by the T than the N during six weeks. The number of steps and PA did not significantly change over time in the N, but significantly increased in the T from weeks one to six (8170±1130 to 12,934±1400 steps/day and 2.6±0.5 to 5.0±0.8 METs·h/day). In addition, significantly more body fat was lost in the T, than in the N (-1.1±0.2 vs. -0.1±0.3 kg), and the changes in PA significantly correlated with the changes in body fat (r=-0.713). CONCLUSIONS: Lifestyle intervention can increase daily PA and reduce body fat more effectively when using an activity monitor and Twitter than an activity monitor alone.

Quantitative assessment of the effect of purity on the properties of single wall carbon nanotubes.

We quantitatively demonstrate the importance of high purity for the application of single wall carbon nanotubes (SWCNTs), materials solely composed of one surface, by examining the effects of carbon impurities on the electrical, thermal, and mechanical properties of both as-grown SWCNT forests and processed buckypaper. While decreases in properties were expected, our results showed the extreme sensitivity of SWCNT properties to carbonaceous impurities either through scattering in the individual SWCNTs or an inhibition of the ability to form inter-SWCNT junctions. Each property showed a nonlinear decrease (as high as 40%) with the addition of low levels of carbon impurities (∼15 wt%), which demonstrates that purity is as important as the crystalline structure.

Effectiveness of scaffolds with pre-seeded mesenchymal stem cells in bone regeneration--assessment of osteogenic ability of scaffolds implanted under the periosteum of the cranial bone of rats.

To date, there has been no study on the development of novel regimens based on the following tissue engineering principles: seeding and culturing mesenchymal stem cells (MSCs) on a scaffold before surgery or injecting cultured MSCs into a scaffold during surgery. The purpose of this study was to assess the in vivo osteogenic ability of scaffold/MSCs implanted beneath the periosteum of the cranial bone of rats in three different sample groups: one in which MSCs were pre-seeded and cultured on a scaffold to produce the 3-D woven fabric scaffold/MSC composite using osteo-lineage induction medium, one in which cultured MSCs produced by osteo-lineage induction in cell cultivation flasks were injected into a scaffold during surgery and a control group, in which only the 3-D woven fabric scaffold was implanted. The results indicate that pre-seeding MSCs on a scaffold leads to a higher osteogenic ability than injecting cultured MSCs into a scaffold during surgery.