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The ice nucleation activities of five different Pseudomonas syringae, Pseudomonas viridiflava and Erwinia herbicola bacterial species and of Snomax™ were investigated in the temperature range between −5 and −15 • C. Water suspensions of these bacteria were directly sprayed into the cloud chamber of the AIDA facility of Forschungszentrum Karlsruhe at a temperature of −5.7 • C. At this temperature, about 1% of the Snomax™ cells induced immersion freezing of the spray droplets before the droplets evaporated in the cloud chamber. The living cells didn't induce any detectable immersion freezing in the spray droplets at −5.7 • C. After evaporation of the spray droplets the bacterial cells remained as aerosol particles in the cloud chamber and were exposed to typical cloud formation conditions in experiments with expansion cooling to about −11 • C. During these experiments, the bacterial cells first acted as cloud condensation nuclei to form cloud droplets. Then, only a minor fraction of the cells acted as heterogeneous ice nuclei either in the condensation or the immersion mode. The results indicate that the bacteria investigated in the present study are mainly ice active in the temperature range between −7 and −11 • C with an ice nucleation (IN) active fraction of the order of 10 −4 . In agreement to previous literature results, the ice nucleation efficiency of Snomax™ cells was much larger with an IN active fraction of 0.2 at temperatures around −8 • C.

It has become evident that students have diverse preferred learning styles and effective instructors must design and deliver courses to meet the needs of those students. This study investigates the four physiological learning styles of visual, aural, read‐write and kinesthetic as they apply to online education. Findings suggest that online students are more likely to have stronger visual and read‐write learning styles. Further, read‐write learners and students that were strong across all four learning styles were likely to evaluate course effectiveness lower than other students while aural/readwrite learners and students that were not strong on any learning style were more likely to evaluate course effectiveness higher than other students.

Background: Medium chain triglycerides (MCT) are ketogenic but the relationship between the change in plasma ketones and the change plasma medium chain fatty acids (MCFA)—octanoate, decanoate, or dodecanoate—after an oral dose of MCT is not well-known. An 8 h metabolic study day is a suitable model to assess the acute effects on plasma ketones and MCFA after a dose of tricaprylin (C8), tricaprin (C10), trilaurin (C12) or mixed MCT (C8C10). Objective: To assess in healthy humans the relationship between the change in plasma ketones, and octanoate, decanoate and dodecanoate in plasma total lipids during an 8 h metabolic study day in which a first 20 ml dose of the homogenized test oil is taken with breakfast and a second 20 ml dose is taken 4 h later without an accompanying meal. Results: The change in plasma acetoacetate, β-hydroxybutyrate and total ketones was highest after C8 (0.5 to 3 h post-dose) and was lower during tests in which octanoate was absent or was diluted by C10 in the test oil. The plasma ketone response was also about 2 fold higher without an accompanying meal ( P = 0.012). However, except during the pure C10 test, the response of octanoate, decanoate or dodecanoate in plasma total lipids to the test oils was not affected by consuming an accompanying meal. Except with C12, the 4 h area-under-the-curve of plasma β-hydroxybutyrate/acetoacetate was 2–3 fold higher when no meal was consumed ( P < 0.04). Conclusion: C8 was about three times more ketogenic than C10 and about six times more ketogenic than C12 under these acute metabolic test conditions, an effect related to the post-dose increase in octanoate in plasma total lipids.

Through multiscale simulations, we explore the influence of both smooth and atomically rough indenter tips on the nucleation of dislocations during nanoindentation of single-crystal aluminum. We model the long-range strain with finite element analysis using anisotropic linear elasticity. We then model a region near the indenter atomistically and perform molecular dynamics with an embedded atom method interatomic potential. We find that smooth indenters nucleate dislocations below the surface but rough indenters can nucleate dislocations both at the surface and below. Increasing temperature from 0 to 300 K creates prenucleation defects in the region of high stress and decreases the critical depth.