Influence of temperature on the frictional properties of water-lubricated surfaces

The influence of temperature on the lubricating properties of neat water for tribopairs with varying bulk elasticity moduli and surface hydrophilicity, namely hard-hydrophobic interface (h-HB), hard-hydrophilic interface (h-HL), soft-hydrophobic interface (s-HB), and soft-hydrophilic interface (s-HL), has been investigated. With increasing temperature, the coefficients of friction generally increased due to the decreasing viscosity of water. This change was more clearly manifested from soft interfaces for more feasible formation of lubricating films. Nevertheless, dominant lubrication mechanism appears to be boundary and mixed lubrication even for soft interfaces at all speeds (up to 1200 mm/s) and temperatures (1 to 90 °C) investigated. The results from this study are expected to provide a reference to explore the temperature-dependent tribological behavior of more complex aqueous lubricants, e.g., those involving various additives, for a variety of tribosystems

A new dynamic property of human consciousness

As pointed out by William James, "the consciousness is a dynamic process, not a thing" , during which short term integration is succeeded by another differentiated neural state through the continual interplay between the environment, the body, and the brain itself. Thus, the dynamic structure underlying successive states of the brain is important for understanding human consciousness as a process. In order to investigate the dynamic property of human consciousness, we developed a new method to reconstruct a state space from electroencephalogram(EEG), in which a trajectory, reflecting states of consciousness, is constructed based on the global information integration of the brain. EEGs were obtained from 14 subjects received an intravenous bolus of propopol. Here we show that the degree of human consciousness is directly associated with the information integration capacity of gamma wave, which is significantly higher in the conscious state than in the unconscious state. And we found a new time evolutional property of human consciousness. The conscious state showed a lower dimensional dynamic process which changed to a random-like process after loss of consciousness. This characteristic dynamic property, appeared only in the gamma band, might be used as an indicator to distinguish the conscious and unconscious states and also considered as an important fact for the human consciousness model

The Mesocallis Matsumura (Hemiptera: Aphididae) of the Korean peninsula with descriptions of two new species

This study reviewed the aphid genus Mesocallis from the Korean peninsula. A total of five species are recognized using morphological and molecular evidence, including two new species, Mesocallis (Mesocallis) carpinicola sp. nov. and M. (Paratinocallis) occulta sp. nov., one newly recorded species, M. (M.) pteleae Matsumura, 1919, and the two species M. (M.) sawashibae (Matsumura, 1917) and M. (P.) corylicola (Higuchi, 1972). Species description, illustrations and distributional and biological data were provided for all Korean Mesocallis species along with a pictorial key. Pairwise distances, a neighbor-joining tree and a median-joining network are also given

Pararhabdepyris Gorbatovskii (Hymenoptera: Bethylidae), new to Korea and the first host record of Allobethylus Kieffer

AbstractPararhabdepyris Gorbatovskii (Hymenoptera: Bethylidae) is newly recognized from South Korea. The genus can be easily recognized from other genera in Scleroderminae by having the head wider than it is long, the antenna with 10 flagellomeres, the clypeus with short projected median lobe, and the metasomal tergite II longer than the combined length of remained tergites. Description and illustrations of diagnostic characteristics of Pararhabdepyris paradoxus Gorbatovskii are provided. In addition, the present paper provides the first host record of Allobethylus Kieffer of Scleroderminae from the world. A revised key to genera and species of South Korean Scleroderminae is also presented