1,099 research outputs found
Distribution of Complex and Core Lipids within New Hyperthermophilic Members of the Archaea Domain
Core and complex lipids of several new hyperthermophilic archaeal isolates were analyzed. The organisms belong to the Sulfolobales,Archaeoglobus, Pyrobaculum, and Methanococcus. A detailed structural investigation of complex lipids of Pyrobaculum species is reported. The different lipid structures are of help for
a rapid and simple phylogenetic classification of the new isolates. They are in agreement with the classification based on other features
A new physarum learner for network structure learning from biomedical data
A novel structure learning algorithm for Bayesian Networks based on a Physarum Learner is presented. The
length of the connections within an initially fully connected Physarum-Maze is taken as the inverse Pearson
correlation coefficient between the connected nodes. The Physarum Learner then estimates the shortest indirect
paths between each pair of nodes. In each iteration, a score of the surviving edges is incremented.
Finally, the highest scored connections are combined to form a Bayesian Network. The novel Physarum
Learner method is evaluated with different configurations and compared to the LAGD Hill Climber showing
comparable performance with respect to quality of training results and increased time efficiency for large data
sets
Equilibrium and non-equilibrium effects in relativistic heavy ion collisions
The hypothesis of local equilibrium (LE) in relativistic heavy ion collisions at energies from AGS to RHIC is checked in the microscopic transport model. We find that kinetic, thermal, and chemical equilibration of the expanding hadronic matter is nearly reached in central collisions at AGS energy for t >_ fm/c in a central cell. At these times the equation of state may be approximated by a simple dependence P ~= (0.12-0.15) epsilon. Increasing deviations of the yields and the energy spectra of hadrons from statistical model values are observed for increasing bombarding energies. The origin of these deviations is traced to the irreversible multiparticle decays of strings and many-body (N >_ 3) decays of resonances. The violations of LE indicate that the matter in the cell reaches a steady state instead of idealized equilibrium. The entropy density in the cell is only about 6% smaller than that of the equilibrium state
Rollator usage lets young individuals switch movement strategies in sit-to-stand and stand-to-sit tasks
\ua9 2023, Springer Nature Limited.The transitions between sitting and standing have a high physical and coordination demand, frequently causing falls in older individuals. Rollators, or four-wheeled walkers, are often prescribed to reduce lower-limb load and to improve balance but have been found a fall risk. This study investigated how rollator support affects sit-to-stand and stand-to-sit movements. Twenty young participants stood up and sat down under three handle support conditions (unassisted, light touch, and full support). As increasing task demands may affect coordination, a challenging floor condition (balance pads) was included. Full-body kinematics and ground reaction forces were recorded, reduced in dimensionality by principal component analyses, and clustered by k-means into movement strategies. Rollator support caused the participants to switch strategies, especially when their balance was challenged, but did not lead to support-specific strategies, i.e., clusters that only comprise light touch or full support trials. Three strategies for sit-to-stand were found: forward leaning, hybrid, and vertical rise; two in the challenging condition (exaggerated forward and forward leaning). For stand-to-sit, three strategies were found: backward lowering, hybrid, and vertical lowering; two in the challenging condition (exaggerated forward and forward leaning). Hence, young individuals adjust their strategy selection to different conditions. Future studies may apply this methodology to older individuals to recommend safe strategies and ultimately reduce falls
- …