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With a newly developed swelling pressure apparatus, swelling pressure tests were conducted to elucidate initial water content and specimen preparation method effects on swelling pressures (swelling pressure evaluation curve and equilibrium swelling pressure) of Kunigel-V1 bentonite. X-ray diffraction (XRD) tests were conducted to investigate the initial water content and specimen preparation method effects on basal spacing, including basal spacings of specimens before and after wetting. Experiments produced the following results. (1) The swelling pressure evaluation curve changed from a line with peak and valley to a line with early-stage steady rise as increasing initial water content. (2) The initial water content and specimen preparation method exerted no apparent effect on the equilibrium swelling pressure. (3) Basal spacing of the specimen before wetting was affected not only by the initial water content but also by the specimen preparation method. (4) The initial water content did not influence the basal spacing of the specimen after wetting. It was only affected by the specimen preparation method. Based on the swelling pressure evaluation curve patterns, swelling mechanisms during saturation for specimens with different initial conditions were discussed. Initial water content and specimen preparation method effects on equilibrium swelling pressure were explained carefully with basal spacings.

This study starts from a question: how would initial water content (wi) affect equilibrium swelling pressure (peq) of compacted bentonites in swelling pressure tests (ps tests)? However, discussions based on experiments involving a bentonite, Kunigel V1 (K_V1), are extended to the following issues: (a) the effect of wi on peq; (b) pore water density (ρpw); (c) the co-existence of crystalline and osmotic swelling; and (d) relation between peq and compaction tests (pc tests). It is revealed that wi has an insignificant effect on peq in general, although a significant effect may appear for relatively high wi and dry density (ρd) conditions. Two swelling types, crystalline swelling with basal spacing of montmorillonite (d001 = 1·0–1·9 nm) and osmotic swelling (d001 ≥ ∼4·0 nm), co-exist in a w range from 36 to 65%. With the fact that ρpw of K_V1 may range from 1·1 to 1·2 Mg/m3, it is expected that crystalline swelling may mainly govern peq in ps tests if the final dry density of a specimen (ρdf) is larger than 1·46 Mg/m3, while osmotic swelling may mainly govern if ρdf 3. Together with the results of pc tests, the effects of wi on peq are explained by the proposed conceptual model.

Crystal field level scheme of a uniaxial chiral helimagnet YbNi$_3$Al$_9$, exhibiting a chiral magnetic soliton lattice state by Cu substitution for Ni, has been determined by inelastic neutron scattering. The ground and the first excited doublets are separated by 44 K and are simply expressed as $\alpha|\pm 7/2\rangle + \beta |\mp 5/2\rangle$ with $\alpha$ and $\beta$ nearly equal to $\pm 1/\sqrt{2}$. The easy axis of the crystal field anisotropy is the $c$ axis when the excited levels are populated at high temperatures and high magnetic fields. On the other hand, the magnetism at low temperatures and low magnetic fields, where only the ground doublet is populated, is described by an easy plane anisotropy which may be treated as an $S=1/2$ system with an anisotropic $g$-factor, $g_{xy}=3.02$ and $g_z=1.14$. An orbital dependent exchange interaction is also discussed to explain the temperature dependence of the magnetic susceptibility based on this level scheme., Comment: 9 pages, 7 figures, 2 figures in the supplemental material, accepted for publication in Phys. Rev. B

A testing procedure was proposed to study water movement in compacted bentonite and the development of swelling pressure (ps) when compacted bentonite specimens were wetted. In this procedure, a multi-ring mold was introduced for ps measurements, after which the specimen was sliced for X-ray diffraction to find movement of water in the interlayer space of montmorillonite. Results revealed a relation between four phases of ps development and evolution of four states of interlayer water molecule arrangement of montmorillonite (L): when ps reached its first peak in phase I, L moved from 1 row water arrangement (1w) to at least 2w; when ps decreased and re-increased in phases II or III, L moved from 2w to at least 3w; and when ps reached a steady state in phase IV, L = 3w. The w distribution in the compacted bentonite was also measured as water absorption time increased. Based on those results, the global water movement was estimated in terms of diffusivity (D) following a method employing Boltzmann transform. Results of comparisons implied that D calculated using this method matched experimental data well and the method was rather easily handled.

This study was performed to elucidate whether eicosapentaenoic acid (EPA) suppresses spasm-prone blood vessel contractions induced by a thromboxane mimetic (U46619) and prostaglandin F2α (PGF2α) and determine whether the primary target of EPA is the prostanoid TP receptor. Accordingly, we assessed: (1) the tension changes in porcine basilar and coronary arteries, and (2) changes in the Fura-2 (an intracellular Ca2+ indicator) fluorescence intensity ratio at 510 nm elicited by 340/380 nm excitation (F340/380) in 293T cells expressing the human TP receptor (TP-293T cells) and those expressing the human prostanoid FP receptor (FP-293T cells). EPA inhibited both porcine basilar and coronary artery contractions induced by U46619 and PGF2α in a concentration-dependent manner, but it did not affect the contractions induced by 80 mM KCl. EPA also inhibited the increase in F340/380 induced by U46619 and PGF2α in TP-293T cells. In contrast, EPA showed only a marginal effect on the increase in F340/380 induced by PGF2α in FP-293T cells. These findings indicate that EPA strongly suppresses the porcine basilar and coronary artery contractions mediated by TP receptor and that inhibition of TP receptors partly underlies the EPA-induced inhibitory effects on these arterial contractions.

Macrophage mannose receptor (MMR/CD206) is a promising target for the detection and identification of sentinel lymph node (SLN). MMR-targeting probes have been developed using mannosylated dextran, however, impairment of efficient targeting of SLN was often caused because of retention of injection site in which macrophages and dendritic cells exist. In this study, we prepared new MMR-targeting probes from yeast mannan (85 kDa), and its bioditribution was investigated. In-vivo evaluation showed that 11.9% of injected dose of 99mTc-labeled mannan-S-cysteines (99mTc-MSCs) was accumulated in popliteal lymph node (the SLN in this model), however, significant level of radioactivity (approximately 80%) was remained in injection site. Interestingly, 99mTc-labeled low molecular weight mannan-S-cysteine mannan (99mTc-LSC) prepared from 50 and 25 kDa mannan showed a decreased specific accumulation of 99mTc-LSC in the popliteal lymph node, while the radioactivity at the injection site remained unchanged. These results suggest that the molecular size, or nature/shape of the sugar chain is important for the specific accumulation of 99mTc-MSC in popliteal lymph node.

The composition of cellulosomal carbohydrate-active enzymes (CAZymes) secreted from a cellulolytic bacterium Clostridium thermocellum varies depending on the cellulosic substrate used during cultivation. C. thermocellum detects the polysaccharides in cellulosic material via anti-sigma factors and expresses the appropriate CAZyme gene via alternative sigma factors, SigIs. Previous studies on the regulation of CAZyme gene expression via SigIs in C. thermocellum have been conducted in vitro or in a heterologous host, because of the limited genetic tools available for C. thermocellum. To characterize the in vivo function of SigIs, in the present study, we established a sigI7 gene expression strain of C. thermocellum. Transcriptome analysis of this strain revealed that SigI7 induced the expression of cellulosomal CAZyme genes and cellulosomal scaffold genes. However, there was a decrease in the degradation ability of the exoproteome from the sigI7 expression strain; the product of the downregulated gene, Clo1313_1002, rescued the activity of the C. thermocellum exoproteome from the sigI7 expression strain. In this study, we demonstrate the in vivo function of SigI7 and discuss the CAZymes that are important for cellulosic biomass degradation by C. thermocellum.

Docosahexaenoic acid (DHA, an n-3 polyunsaturated fatty acid) inhibits U46619 (a TP receptor agonist)- and prostaglandin F

We have measured the magnetization of rare-earth chiral magnets Yb(Ni$_{1-x}$Cu$_x$)$_{3}$Al$_{9}$ for $x$=0 and 0.06 up to 14.5 T. Magnetization for the field direction $H \parallel c$, which is the hard axis at low temperatures and low fields, overtakes the easy axis magnetization for $H \perp c$ above $\sim$4 T. We analyzed this overtaking of the magnetization curves by considering a crystalline electric field model. It is shown that the $B_{66}$ term, which connects the $|\pm5/2 \rangle$ and the $|\mp7/2\rangle$ states through the off-diagonal matrix element, is responsible for the characteristic magnetization process in this compound. We also introduce orbital dependent exchange interactions to explain the temperature dependence of magnetic susceptibility., 6 pages, 3 figures, proceedings of SCES2019

Docosahexaenoic acid (DHA, an n-3 polyunsaturated fatty acid) inhibits U46619 (a TP receptor agonist)- and prostaglandin F2α-induced contractions in rat aorta and mesenteric arteries. However, whether these effects could be replicated in vasospasm-prone vessels, such as coronary and cerebral arteries, remains unknown. Here, we evaluated the changes in pig coronary and basilar artery tensions and intracellular Ca2+ concentrations in human prostanoid TP or FP receptor-expressing cells. We aimed to clarify whether DHA inhibits U46619- and prostaglandin F2α-induced contractions in spasm-prone blood vessels and determine if the TP receptor is the primary target for DHA. In both pig coronary and basilar arteries, DHA suppressed U46619- and prostaglandin F2α-induced sustained contractions in a concentration-dependent manner, but did not affect contractions induced by 80 mM KCl. SQ 29,548 (a TP receptor antagonist) suppressed U46619- and prostaglandin F2α-induced contractions by approximately 100% and 60%, respectively. DHA suppressed both U46619- and prostaglandin F2α-induced increases in intracellular Ca2+ concentrations in human TP receptor-expressing cells. However, DHA did not affect prostaglandin F2α-induced increases in intracellular Ca2+ concentrations in human FP receptor-expressing cells. These findings suggest that DHA potently inhibits TP receptor-mediated contractions in pig coronary and basilar arteries, and the primary mechanism underlying its inhibitory effects on arterial contractions involves inhibiting TP receptors.

In this study, we introduce EyeHacker, which is an immersive virtual reality (VR) system that spatiotemporally mixes the live and recorded/edited scenes based on the measurement of the users' gaze. This system updates the transition risk in real time by utilizing the gaze information of the users (i.e., the locus of attention) and the optical flow of scenes. Scene transitions are allowed when the risk is less than the threshold, which is modulated by the head movement data of the users (i.e., the faster their head movement, the higher will be the threshold). Using this algorithm and experience scenario prepared in advance, visual reality can be manipulated without being noticed by users (i.e., eye hacking). For example, consider a situation in which the objects around the users perpetually disappear and appear. The users would often have a strange feeling that something was wrong and, sometimes, would even find what happened but only later; they cannot visually perceive the changes in real time. Further, with the other variant of risk algorithms, the system can implement a variety of experience scenarios, resulting in reality confusion.

Macrophage mannose receptor (MMR/CD206) is a promising target for the detection and identification of sentinel lymph node (SLN). MMR-targeting probes have been developed using mannosylated dextran, however, impairment of efficient targeting of SLN was often caused because of retention of injection site in which macrophages and dendritic cells exist. In this study, we prepared new MMR-targeting probes from yeast mannan (85 kDa), and its bioditribution was investigated. In-vivo evaluation showed that 11.9% of injected dose of

Chondroitin sulfate (CS) has been accepted as an ingredient in health foods for the treatment of symptoms related to arthritis and cartilage repair. However, CS is poorly absorbed through the gastrointestinal tract because of its high negative electric charges and molecular weight (MW). In this study, poly-ion complex (PIC) formation was found in aqueous solutions through electrostatic interaction between CS and polyamines-organic molecules having two or more primary amino groups ubiquitously distributed in natural products at high concentrations. Characteristic properties of various PICs generated by mixing CS and natural polyamines, including unusual polyamines, were studied based on the turbidity for PIC formation, the dynamic light scattering for the size of PIC particles, and ζ-potential measurements for the surface charges of PIC particles. The efficiency of PIC formation between CS and spermine increased in a CS MW-dependent manner, with 15 kDa CS being critical for the formation of PIC (particle size: 3.41 µm) having nearly neutral surface charge (ζ-potential: -0.80 mV). Comparatively, mixing tetrakis(3-aminopropyl)ammonium and 15 kDa of CS afforded significant levels of PIC (particle size: 0.42±0.16 µm) despite a strongly negative surface charge (-34.67±1.15 mV). Interestingly, the oral absorption efficiency of CS was greatly improved only when PIC possessing neutral surface charges was administered to mice. High formation efficiency and electrically neutral surface charge of PIC particles are important factors for oral CS bioavailability.

Physical mixtures of cationic polymers and heparin have been developed to overcome the limitations of unfractionated heparin. In this study, we found that heparin associates with natural polyamines in water, resulting in the generation of a poly-ion complex (PIC). PIC formation (or stability) was influenced by the concentration and ratio of heparin and polyamines, molecular weight of heparin, nature of polyamines, and pH conditions. Interestingly, the PIC obtained when heparin and tetrakis (3-aminopropyl) ammonium (Taa) were mixed exhibited stability and was sticky in nature. PIC formation was due to an electrostatic interaction between heparin and Taa. Heparin-Taa PIC was administered subcutaneously to mice, and the time to maximum heparin concentration within the therapeutic range of heparin was markedly increased compared to that after a single dose of heparin. These results suggest that the quaternary ammonium structure of Taa is critical for the preparation of a stable PIC, thereby allowing the sustained release of heparin into the blood., Poly-ion complex; Polyamine; Sustained release of heparin; Materials application; Materials characterization; Biotechnology; Pharmaceutical science; Biomedical engineering

In Japanese project for disposal of high-level radioactive waste, the self-sealing capability of bentonite buffer material, which results from the swelling deformation to fill the gaps between waste container and wall of disposal pit, must be retained thousands of years. However, because of the effect of high pressures, occurrence of cementation and property changes of the buffer material are a concern. Few studies had examined cementation effects because of the difficulties for simulating long-term alteration process experimentally. In this paper, swelling properties of consolidated buffer are regarded as similar as those of naturally consolidated bentonite ore. Therefore, three kinds of bentonite ores were used for experiments to elucidate influences of cementation on self-sealing capabilities. Undisturbed and reconstituted specimens were prepared to assess their swelling pressures after filling a preset gap in a swelling pressure apparatus. Results show that for Japanese ores, the swelling pressure of undisturbed specimens is about half that of reconstituted specimens. For American and Chinese ores, the difference of swelling pressure is greater when the preset gap is smaller. Results imply that effects of cementation on self-sealing capability are smaller when swelling deformation is allowed.