To determine the phase boundary between diaspore (α–AlOOH) and δ–AlOOH, in situ X–ray diffraction experiments were carried out using a multi–anvil high–pressure apparatus and synchrotron X–ray. The ...stability of each phase was determined by observing the change in powder X–ray diffraction patterns. The equilibrium phase boundary is described by the formula P (GPa) = 12.2 (±4.9) + 0.0027 (±0.0044) × T (K). The boundary determined in this study is located at a lower pressure than that estimated by previous quenching experimental studies.
Three types of capillaries, namely continuous, fenestrated, and sinusoidal, form the microvascular system; each type has a specialized structure and function to respond to the demands of the organs ...they supply. The endothelial glycocalyx, a gel-like layer of glycoproteins that covers the luminal surface of the capillary endothelium, is also thought to maintain organ and vascular homeostasis by exhibiting different morphologies based on the functions of the organs and capillaries in which it is found. Recent advances in analytical technology have enabled more detailed observations of the endothelial glycocalyx, revealing that it indeed differs in structure across various organs. Furthermore, differences in the lectin staining patterns suggest the presence of different endothelial glycocalyx components across various organs. Interestingly, injury to the endothelial glycocalyx due to various pathologic and physiological stimuli causes the release of these components into the blood. Thus, circulating glycocalyx components may be useful biomarkers of organ dysfunction and disease severity. Moreover, a recent study suggested that chronic injury to the glycocalyx reduces the production of these glycocalyx components and changes their structure, leading it to become more vulnerable to external stimuli. In this review, we have summarized the various endothelial glycocalyx structures and their functions.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The viscosity of melt of soda melilite (CaNaAlSi2O7) composition was measured using the falling sphere method with synchrotron X–ray radiography. This composition of melt was used as a model basalt, ...because the ratio of the non–bridging oxygen (NBO) and the tetrahedrally coordinated (T) cation is 0.67. We observed a viscosity minimum between 2 and 4 GPa. This finding shows that the partially depolymerized melt (NBO/T = 0.67) has a viscosity minimum under high pressure.
Viscosity is one of the important transport properties controlling the migration of magma in the Earth’s interior. Experimental and geochemical studies have shown that magma is generated in the deep ...interior in the presence of CO2. However, our knowledge of the effect of CO2 on the viscosity of magma (silicate melt) is limited. In this work, the viscosity of a molten jadeite composition containing 0.5 wt% CO2 was measured under high pressure. We observed that in the presence of CO2, the viscosity was one to two orders of magnitude lower than without CO2.
The pressure-volume-temperature (P-V-T) equation of state (EoS) of natural goethite (α-FeOOH) has been determined by an X-ray diffraction study using synchrotron radiation. Fitting the volume data to ...the third-order Birch-Murnaghan EoS yielded an isothermal bulk modulus, B
0
of 85.9(15) GPa, and a pressure derivative of the bulk modulus, B′, of 12.6(8). The temperature derivative of the bulk modulus, (∂B/∂T)
P
, was -0.022(9) GPa K
−1
. The thermal expansion coefficient α
0
was determined to be 4.0(5) × 10
−5
K
−1
.
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BFBNIB, DOBA, GIS, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
The viscosity of alkali titanosilicate melt with a composition of K2TiSi4O11 (KTS4) was measured at pressures up to of 7.41 GPa and temperatures up to of 2133 K. The aim of this study is to determine ...the effect of pressure on the viscosity change and to estimate the relation between structural change and the viscosity change under high pressures. The viscosity decreased up to 3.30 GPa, whereas it increased from 3.30 to 7.41 GPa. The viscosity change above 3.30 GPa is likely caused by the dominance of six–fold coordinated titanium.
This article discusses development and verification test results of the 6.6-kV 200-kVA transformerless static synchronous compensator (STATCOM). This STATCOM is characterized by the use of a modular ...multilevel single-delta bridge-cell (SDBC) converter and silicon carbide metal-oxide-semiconductor field-effect transistor (MOSFET) modules. The article discusses a control method for the 6.6-kV system with focus on dc-capacitor voltage control. The voltage control presented in this article is different from the ones presented earlier. It consists of intercluster balancing control and intracluster balancing control. The former, also known as cluster balancing control, eliminates the requirement of the separate overall dc-voltage control present in conventional methods, whereas the latter, also known as individual balancing control, is replaced with a new technique based on the control of a dead time of each bridge cell. The article makes a detailed description of the latter. Experimental results obtained from the 6.6-kV 200-kVA verification test equipment validate the effectiveness of the control method. Moreover, successful test results confirm the efficacy of the system for grid-voltage regulation and load compensation.
A new synchrotron X–ray diffraction study of ε–FeOOH has been carried out to determine the pressure–volume–temperature (P–V–T) equation of state (EOS). The P–V–T data fitted a third–order ...Birch–Murnaghan EOS yielded: isothermal bulk modulus KT0 of 135(3) GPa; its pressure derivative K′ of 6.1(9); (∂KT/∂T)P of −0.05(2) GPa K−1; a0 of 2.6(7) × 10−5 K−1 and a1 of 1.0(3) × 10−7 K−2, where the volumetric thermal expansion coefficient is described as α0,T = a0 + a1 × (T − 300).
Long-term synaptic plasticity requires a mechanism that converts short Ca2+ pulses into persistent biochemical signaling to maintain changes in the synaptic structure and function. Here, we present a ...novel mechanism of a positive feedback loop, formed by a reciprocally activating kinase-effector complex (RAKEC) in dendritic spines, enabling the persistence and confinement of a molecular memory. We found that stimulation of a single spine causes the rapid formation of a RAKEC consisting of CaMKII and Tiam1, a Rac-GEF. This interaction is mediated by a pseudo-autoinhibitory domain on Tiam1, which is homologous to the CaMKII autoinhibitory domain itself. Therefore, Tiam1 binding results in constitutive CaMKII activation, which in turn persistently phosphorylates Tiam1. Phosphorylated Tiam1 promotes stable actin-polymerization through Rac1, thereby maintaining the structure of the spine during LTP. The RAKEC can store biochemical information in small subcellular compartments, thus potentially serving as a general mechanism for prolonged and compartmentalized signaling.
•Persistent Rac1 activity is required for structural LTP of dendritic spines•CaMKII stably binds on pseudo-autoinhibitory domain of Tiam1, a Rac-GEF•This binding disinhibits autoinhibition of CaMKII and maintains its activity•Persistently activated CaMKII phosphorylates Tiam1 and maintains Rac1 activity
Saneyoshi et al. find that stimulation of single spine causes rapid formation of a reciprocally activating signaling complex between CaMKII and a Rac-GEF Tiam1, which stably activates Rac1 and maintains enlarged spine structure during LTP.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Anti-prion protein (PrP) monoclonal antibody 132, which recognizes mouse PrP amino acids 119-127, enables us to reliably detect abnormal isoform prion protein (PrPSc) in cells or frozen tissue ...sections by immunofluorescence assay, although treatment with guanidinium salts is a prerequisite. Despite the benefit of this mAb, the mechanism of PrPSc-specific detection remains unclear. Therefore, to address this mechanism, we analyzed the reactivities of mono- and bivalent mAb 132 to recombinant mouse PrP (rMoPrP) by enzyme-linked immunosorbent assay (ELISA) and surface plasmon resonance (SPR). In ELISA, binding of the monovalent form was significantly weaker than that of the bivalent form, indicating that bivalent binding confers a higher binding stability to mAb 132. Compared with other anti-PrP mAbs tested, the reactivity of bivalent mAb 132 was easily affected by a decrease in antigen concentration. The binding kinetics of mAb 132 assessed by SPR were consistent with the results of ELISA. The dissociation constant of the monovalent form was approximately 260 times higher than that of the bivalent form, suggesting that monovalent binding is less stable than bivalent binding. Furthermore, the amount of mAb 132 that bound to rMoPrP decreased if the antigen density was too low to allow bivalent binding. If two cellular PrP (PrPC) are close enough to allow bivalent binding, mAb 132 binds to PrPC. These results indicate that weak monovalent binding to monomeric PrPC diminishes PrPC signals to background level, whereas after exposure of the epitope, mAb 132 binds stably to oligomeric PrPSc in a bivalent manner.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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