Estimation of the Cutting Force Using the Dynamic Friction Coefficient Obtained by Reaction Force During the Needle Insertion

Estimation of the linear thermal expansi

Estimation of the linear thermal expansion coefficient in friction-deposited, oriented poly(tetrafluoroethylene) films by temperature-dependent lateral force microscopy

✍ Stefan Förster; Guobin Liu; G. Julius Vancso 📂 Article 📅 1996 🏛 Springer 🌐 English ⚖ 832 KB

Does support surface coefficient of fric

Does support surface coefficient of friction influence postural dynamics and isometric force productions of the upper extremities performed by seated subjects?

✍ C Gaudez; S Le Bozec; J Richardson 📂 Article 📅 2004 🏛 Elsevier Science 🌐 English ⚖ 142 KB

The friction coefficient of a Lennard-Jo

The friction coefficient of a Lennard-Jones fluid from the random force autocorrelation function determined as a memory function by molecular dynamics calculations

✍ R. Vogelsang; C. Hoheisel 📂 Article 📅 1989 🏛 Springer 🌐 English ⚖ 609 KB

Saliva and serum samples were collected

Saliva and serum samples were collected from eight healthy volunteers every two hours during a 26-hour period. Melatonin concentrations were measured by radioimmunoassay after chloroform extraction using radioiodinated melatonin as a tracer. Five of the subjects had high serum melatonin levels at night (peak levels higher than 75 pg/ml); in three subjects the highest serum melatonin concentration was 20-40 pg/ml. All subjects had low levels (P <0.001, was obtained for all detectable value pairs (n= 73). The regression and correlation coefficients were almost equal for the peak values of melatonin and during the rising and descending phases of the secretion patterns. However, no significant correlation was found between low daytime salivary and serum concentrations when calculated separately. In the five high-secretors the melatonin levels in saliva reflected reliably the changes in serum, but in the three low-secretors the correlation between salivary and serum melatonin was not significant. The proportion of melatonin found in saliva decreased with increasing serum melatonin levels. Circadian rhythm parameters were estimated by single cosinor analysis. The acrophases did not differ significantly within a subject in the concomitant measurements of serum and salivary melatonin. The measurements of salivary melatonin levels seem valid for studies on melatonin rhythms, but the melatonin concentrations measured in saliva do not always consistently reflect the absolute concentrations in blood.

✍ Maija-Liisa Laakso; Tarja Porkka-Heiskanen; Aino Alila; Dag Stenberg; Gunnar Joh 📂 Article 📅 1990 🏛 John Wiley and Sons 🌐 English ⚖ 622 KB