It Pays To Be in Phase Itakura, Alan K; Futia, Raymond A; Jarosz, Daniel F
Biochemistry,
05/2018, Volume:
57, Issue:
17
Journal Article
Peer reviewed
Open access
To survive, organisms must orchestrate competing biochemical and regulatory processes in time and space. Recent work has suggested that the underlying chemical properties of some biomolecules allow ...them to self-organize and that life may have exploited this property to organize biochemistry in space and time. Such phase separation is ubiquitous, particularly among the many regulatory proteins that harbor prion-like intrinsically disordered domains. And yet, despite evident regulation by post-translational modification and myriad other stimuli, the biological significance of many phase-separated compartments remains uncertain. Many potential functions have been proposed, but far fewer have been demonstrated. A burgeoning subfield at the intersection of cell biology and polymer physics has defined the biophysical underpinnings that govern the genesis and stability of these particles. The picture is complex: many assemblies are composed of multiple proteins that each have the capacity to phase separate. Here, we briefly discuss this foundational work and survey recent efforts combining targeted biochemical perturbations and quantitative modeling to specifically address the diverse roles that phase separation processes may play in biology.
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IJS, KILJ, NUK, PNG, UL, UM
Underground Coal Gasification (UCG) is a technology to recover combustible gases by drilling holes and in-situ gasification. The establishment of a safe UCG system requires monitoring of the ...gasification reaction area because the gasification process that occurs in the underground is an invisible event. It is considered that Acoustic Emission (AE) monitoring is an effective technique for monitoring the underground gasification area since many fracturing activities occur in the coal seam due to coal heating. Therefore, the temperature condition of AE generations is investigated using the coal heating experiments and examines the applicability of AE measurement as a monitoring method for UCG. Measurements of temperature change and AE events with the thermocouples and the acceleration transducers during the coal specimen were heated. As a result, many AE events are found when the temperature of coal is changed and detected in the sensor where its location was near the heat source. Additionally, AE sources are expanded widely with the expansion of the high-temperature region based on the analysis results of the AE source location. It is possible to monitor the temperature change of coal and the expansion of the high-temperature region by applying AE measurement monitoring during UCG.
We present a systematic, and fully analytic, study of the ratio
R
p
A
between the gluon distribution in a nucleus and that in a proton scaled up by the atomic number
A. We consider initial conditions ...of the McLerran–Venugopalan type, and quantum evolution in the Color Glass Condensate, with both fixed and running coupling. We perform an analytic study of the Cronin effect in the initial conditions and point out an interesting difference between saturating effects and twist effects in the nuclear gluon distribution. We show that the distribution of the gluons which make up the condensate in the initial conditions is localized at low momenta, but this particular feature does not survive after the quantum evolution. We demonstrate that the rapid suppression of the ratio
R
p
A
in the early stages of the evolution is due to the DGLAP-like evolution of the proton, whose gluon distribution grows much faster than that in the nucleus because of the large separation between the respective saturation momenta. The flattening of the Cronin peak, on the other hand, is due to the evolution of the nucleus. We show that the running coupling effects slow down the evolution, but eventually lead to a stronger suppression in
R
p
A
at sufficiently large energies.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
We propose an effective theory which governs pomeron dynamics in QCD at high energy, in the leading logarithmic approximation, and in the limit where Nc, the number of colors, is large. In spite of ...its remarkably simple structure, this effective theory generates precisely the evolution equations for scattering amplitudes that have been recently deduced from a more complete microscopic analysis. It accounts for the BFKL evolution of the pomerons together with their interactions: dissociation (one pomeron splitting into two) and recombination (two pomerons merging into one). It is constructed by exploiting a duality principle relating the evolutions in the target and the projectile, more precisely, splitting and merging processes, or fluctuations in the dilute regime and saturation effects in the dense regime. The simplest pomeron loop calculated with the effective theory is free of both ultraviolet or infrared singularities.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Machine elements in humanoid robots for our life support require light weight, high accuracy and high output torque. In order to achieve low transmission error of the humanoid robot joints, wear of ...reinforced poly-ether-ether-ketone (PEEK) bushes against the 7075 aluminium alloy cam plates is investigated. Sliding fatigue wear tests of PEEK bushes in the humanoid robot leg joint were performed under various load torques. In the case of the bush under 127 Nm load torque at 5·7 mm s
−1
sliding velosity, the backlash values were stable after the running process in fatigue wear test. PEEK film was formed by the friction between PEEK bush and 7075 cam plate under compression load. The oscillation angle of the output axis in the robot joint was stable after early stage because of the solid lublication caused by the film. This means the backlash value was stable and decreased due to the PEEK film between the bush and the cam plate.
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BFBNIB, GIS, IJS, KISLJ, NUK, PNG, UL, UM, UPUK
A system simulation model of a solid oxide redox flow battery (SORFB) was developed and calculations were carried out to investigate fundamental characteristics of the system. The SORFB is a new-type ...storage battery consisting of solid oxide electrochemical cell (SOEC) and redox metal; as redox metal, iron is assumed. The developed model is based on 0-D models of the consisting components such as SOEC, redox reactor and heat exchangers. The energy flow of one cycle of charge/discharge operation was evaluated. The results provide foundation for discussion on the system efficiency of SORFB.
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