Search

After the 2011 Tohoku-oki earthquake, a seafloor observation system observed rapid landward deformation. These seafloor observation data are potentially explicable via modeling of a low-viscosity zone under the subducting plate, called the lithosphere–asthenosphere boundary (LAB). However, the effect of a low-viscosity LAB has not been empirically examined in past earthquakes because of the absence of seafloor observation data, which are expected to have high sensitivity in the detection of a low-viscosity LAB. The Nankai Trough, southwest Japan, is one location where seafloor geodetic stations are in operation that could detect a low-viscosity LAB after a future earthquake. Therefore, we quantitatively model how the low-viscosity of the LAB is expected to affect postseismic crustal deformation following an anticipated future large earthquake under the Nankai Trough. Calculating viscoelastic deformation using a model that takes into account the realistic crustal structure in the southwestern Japanese Archipelago, we examine the effects of LAB viscosity on surface deformation patterns. The results show for very low LAB viscosities ( 2.5 × 10 17 Pa s), rapid landward displacement as large as 38 cm/yr occurs in the offshore area, with uplift and subsidence patterns highly dependent on the viscosity structure. Especially in the first year after the earthquake, the difference in deformation between the cases with and without a low-viscosity LAB was much larger than the observational error level of the current seafloor observation system. For such low LAB viscosities, the probability of detection is therefore high. On the other hand, for moderately low LAB viscosities ( 2.5 × 10 18 Pa s), the deformation patterns in the cases with and without a low-viscosity LAB are similar. Indeed, the difference in displacement lies within the observational error level of the current observational network, so detection is expected to be difficult for a LAB of only moderately low-viscosity. However, such a LAB may be detected by improving observational accuracy in the Global Navigation Satellite System–acoustic observation technique by performing more frequent measurements. Additional detection potential lies in expected future accuracy improvements in vertical displacement estimates at the DONET stations. [ABSTRACT FROM AUTHOR]

Ultramylonites are among the most extreme fault rocks that commonly occur in the mid-crustal brittle–plastic transition and are mainly characterized by intensely sheared fine-grained microstructures and well-mixed mineral phases. Although the deformation mechanism of ultramylonites is key to understanding the rheological behavior of the mid-crustal shear zone, their microstructural development is still controversial owing to their intensely fine-grained textures. To investigate the possible crustal deformation mechanisms, we studied 13 mylonites obtained from the Kashio shear zone along the Median Tectonic Line that is the largest strike-slip fault in Japan. In particular, we investigated various mixed quartz–plagioclase layers developed within tonalitic mylonite, which are representative of the common mean grain size and crystal fabric of quartz among the studied samples. A high-quality phase-orientation map obtained by electron backscattered diffraction showed not only a wide range of quartz–plagioclase mixing (10%–80% in quartz modal composition) but also revealed a correlation between grain size reduction and crystal fabric weakening in quartz, indicating a change in the deformation mechanism from dislocation creep to grain-size-sensitive creep in the mixed quartz-plagioclase layers. In contrast, plagioclase showed an almost consistent fine grain size and weak to random crystal fabrics regardless of modal composition, indicating that grain size-sensitive creep is dominant. Combined with laboratory-determined flow laws, our results show that the Kashio shear zone could have developed under deformation mechanisms in which the viscosities of quartz and plagioclase are nearly comparable, effectively within 1017–1019 Pa·s, thereby possibly enabling extensive shearing along the Median Tectonic Line. [ABSTRACT FROM AUTHOR]

Microbubbles coated by visco-elastic shells are important for ultrasound diagnosis using contrast agents, and the dynamics of single coated bubbles has been investigated in the literature. However, although a high number of contrast agents are used in practical situations, there has long been an absence of a nonlinear acoustic theory for multiple coated bubbles, except for our recent work by Kikuchi and Kanagawa ["Weakly nonlinear theory on ultrasound propagation in liquids containing many microbubbles encapsulated by visco-elastic shell," Jpn. J. Appl. Phys. 60, SDDD14 (2021)], under several assumptions to be excluded. Aiming for generalization, in this study, we theoretically investigate weakly nonlinear propagation of ultrasound in liquid containing multiple bubbles coated by a visco-elastic shell with compressibility. Leveraging the method of multiple scales, both the Korteweg–de Vries–Burgers (KdVB) equation for a low-frequency long wave and nonlinear Schrödinger (NLS) equation for a high-frequency short wave are derived from the volumetric averaged equations for bubbly liquids based on a two-fluid model and the up-to-date model for single coated bubbles with shell compressibility. Neglected factors in our previous paper, i.e., compressibility of the shell and liquid, drag force acting on bubbles, bubble translation, and thermal conduction, are incorporated in the present KdVB and NLS equations; the proposed model will be regarded as a generic physico-mathematical model. The results show that shell compressibility attenuated ultrasound strongly and decreased nonlinearity of ultrasound. Finally, we compared the magnitudes of six dissipation factors (shell compressibility, shell viscosity, liquid compressibility, liquid viscosity, thermal effect, and drag force) for five typical ultrasound contrast agents, and a similar tendency between KdVB and NLS equations was revealed. [ABSTRACT FROM AUTHOR]

Earthquake‐cycle deformation at subduction zones is not only induced by cyclical faulting processes but also impacted by the Earth structure and rheology. Oversimplifying the first‐order Earth structure in models leads to biased estimations of fault kinematics and Earth rheology and hence misinterpretation of subduction‐zone dynamics. Here we first use synthetic models to investigate the impacts of an elastic slab on viscoelastic postseismic and interseismic deformation and on determining afterslip, locking distribution, and mantle viscosity. We confirm that the presence of a slab causes anchored viscous flow in the mantle wedge and less extensive viscoelastic deformation in the overriding plate than the depth‐dependent layered models without a slab during the interseismic and postseismic phases. By assuming the predicted viscoelastic deformation from the model with a slab as the synthetic true observations, layered models obtain a higher viscosity and more slip on the downdip of the seismogenic zone than the true model during both phases. These biased estimates are found varying with the displacement component, spatial and temporal coverages of the used observations. We then conduct two real‐world case studies at the Japan subduction zone and find that the layered model obtains the biased fault kinematics and mantle viscosity that are similar to the synthetic modeling results, indicating that the slab signature may have been observed in the geodetic data. Our findings highlight the importance of including a slab in modeling the earthquake‐cycle deformation and thoroughly exploring the sensitivities of surface deformation, especially the verticals, on the deep Earth structures. Plain Language Summary: A descending oceanic plate (i.e., slab) is much colder and stronger than its surrounding mantle rocks at depth. However, such differences between the slab and its surroundings are often not considered in computational subduction models. In this research, we investigate how different the surface motion is predicted by models with and without a slab and what are the consequences in quantifying the mantle properties at depth as well as the slip on the subduction fault. These two questions are studied by first running purely synthetic models and then applying the models to the real motion data from Japan. We find that if using models without a slab, the mantle is predicted to be stronger and the fault to slip more at depth than the true models. The extents of the deviations depend partially on when and what locations that the data are collected for the study. To better understand the fault kinematics and mantle properties at subduction zones, we suggest to revisit the previous no‐slab models and to correctly include a slab in future models. Key Points: Effects of an elastic slab on the viscoelastic postseismic and interseismic deformation are explored using synthetic models and real casesIgnoring the slab in models leads to a broader horizontal deformation pattern and a contrasting, even reversed, vertical patternLayered models without a slab prefer a higher mantle viscosity and more slip near downdip seismogenic edge in post‐ and interseismic phases [ABSTRACT FROM AUTHOR]

The International Dysphagia Diet Standardization Initiative (IDDSI) proposed the flow test (FT) as a simple method for measuring the viscosity of thickened liquids. However, the FT specifies the use of a particular syringe type (BD‐Slip), which is unfortunately not easily available in Japan. Therefore, the current study primarily aimed to investigate the effects of the internal syringe shape on IDDSI FT and identify the most suitable syringe available in Japan for xanthan gum‐based thickened liquids. Accordingly, four syringes, namely, Luer slip tip, Luer‐Lok tip, TERUMO, and NIPRO syringes, were used to examine FT value with water and nine different water viscosity levels. The correlation and systematic errors on residual FT values between the BD‐Slip syringe and the other three syringes were analyzed. The two‐dimensional internal shapes of the four syringes were measured using industrial computed tomography (CT) scanning. Based on the results of our FT, TERUMO had the smallest error range among the three syringes, without systematic errors. On a CT scan, three of five tip‐shape parameters showed the smallest difference between BD‐Slip and TERUMO syringe. Therefore, TERUMO had the smallest FT error range compared with that in BD‐Slip tip syringe, indicating that TERUMO could be used as a substitute for BD‐Slip when performing IDDSI FT with xanthan gum‐based thickened water in Japan. [ABSTRACT FROM AUTHOR]

We analyzed a relationship between the viscosity and fine current of the ER suspension aiming for an estimation of the inner structure. This study aimed at an estimation of the inner structure formation via the fine current pass through the suspension. Viscosity and electrical current through electrodes were measured using similar apparatuses, and the relationship between the viscosity and fine current was investigated. The ER suspension was prepared by adding silica particles of 0.5 μm diameter to silicone oil of 0.291 Pa˙s viscosity. The solid volume fraction was 0.20. The voltage was varied from 0 to 1.5 kV/mm. The viscosity of the ER suspension was measured by a falling time in a rectangular tube. As a result, the fine current was found to correlate with the viscosity of the ER suspension. It indicated the possibility that the inner structure of the ER suspension can be estimated using the fine current through the ER suspension. © 2021 Institute of Electrical Engineers of Japan. Published by Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Background: Semisolid nutrients have been widely used to prevent complications related to enteral nutrition (EN) in Japan. However, there are few data on the effect of feeding semisolid nutrient preparations. We compared 30-day readmission rates of gastrostomy tube-fed patients who had been prescribed semisolid vs liquid nutrients on discharge.Methods: This is a retrospective observational study using a Japanese nationwide inpatient database of data entered between June 2014 and March 2018. We identified patients aged ≥18 years who had received EN through gastrostomy during hospitalization. Patients were classified as having been prescribed semisolid vs liquid EN on discharge. After one-to-one propensity score matching, all-cause 30-day readmission rates were compared between the 2 groups.Results: In total, 5331 patients were identified, including a semisolid-nutrients group (n = 2089) and a liquid-nutrients group (n = 3242). Propensity score matching created 1912 pairs. The 30-day readmission rates were 15.6% and 13.9% in the semisolid-nutrients and liquid-nutrients groups, respectively. No significant difference was observed between the groups (risk difference, 1.7%; 95% CI, -0.6 to 4.0%; P = .14).Conclusion: All-cause 30-day readmission of patients receiving gastrostomy tube feeding did not differ between those prescribed semisolid vs liquid nutrients on discharge. Randomized controlled trials are needed to accurately determine the effect of semisolid nutrients on clinical outcomes. [ABSTRACT FROM AUTHOR]

In Japan, two 0.4% sodium hyaluronate (HA)-based submucosal injection materials (SIMs) are currently used in endoscopic submucosal dissection (ESD): MucoUp (HA-Mc) and Ksmart (HA-Ks). HA-Mc and HA-Ks have the same concentration and are, thus, construed by most endoscopists to have no difference. Nevertheless, visual observation conveys the impression that HA-Ks have a higher viscosity than HA-Mc, suggesting that HA-Ks performs better than HA-Mc. This study aimed to examine the differences between HA-Mc and HA-Ks. HA-Ks exhibited higher viscosity due to greater weight-average molecular weight compared with HA-Mc. HA-Ks had significantly greater submucosal elevation height (SEH) than HA-Mc; the SEH of HA-Ks-80% (80% dilution of HA-Ks) was the same as that of HA-Mc. The ESD procedure time was significantly shorter with HA-Ks than with HA-Mc (15.2 ± 4.1 vs. 19.5 ± 5.9; P = 0.049). The total injection volume for HA-Ks was significantly lower than that for HA-Mc (10.8 ± 3.6 vs. 14.4 ± 4.6; P = 0.045). However, no significant difference in these items was observed between HA-Mc and HA-Ks-80%. HA-Mc and HA-Ks were considered to be almost the same. Nonetheless, HA-Ks exhibited higher viscosity and SIM performance than HA-Mc. HA-Ks-80% had almost the same performance as HA-Mc. Thus, understanding SIM performance and characteristics requires a focus on the viscosity of SIMs. [ABSTRACT FROM AUTHOR]

In this paper, a two-dimensional sliding block model --discretized in slices- is presented, in which the geometrical, mechanical and rheological variables of the landslide are considered in order to analyse the soil landslide kinematic behaviour. The movement of the sliding mass is presented as a system of adjacent blocks; the movement strength is given by the Coulombviscous rheological model, where the friction and viscous components are considered, represented by a parallel system of a slider and a damper, respectively. The movement equation of the model corresponds to a second order differential equation, which was solved by the finite difference method, obtaining an explicit equation to know the displacement, velocity and acceleration of each block. An algorithm was developed in MATLAB® software, where movement equations were programmed to obtain results of the sliding kinematics. With the algorithm developed it was possible to make a sensitivity analysis to the parameters of the model. This was implemented in the problem of the sliding block at infinity slope, where it was possible to know the influence of each of the parameters of the model. The model has also been applied to the Hiegaesi landslide occurred in Japan in 1998, where the kinematic behaviour has been analysed in the model, regarding the records reported. However, further research is needed in order to apply the published model for prediction of the kinematic behaviour of landslides due to different limitations discussed in this paper. [ABSTRACT FROM AUTHOR]

Spatial viscosity variations in the crust can be inferred from geophysical imaging and may be essential for interpreting volcano deformations that show more complex behaviours than what simple uni-viscous models predict. In southern Kyushu, Japan, recent seismic imaging implies the presence of a low viscosity zone (LVZ) beneath Aira Caldera, and geodetic data in and around the caldera require uni-viscous model to have lower and higher viscosities earliest and later, respectively, in the period following the 1914 eruption of Sakurajima Volcano. Here, we use a 3D finite element model comprising an elastic layer underlain by a linear Maxwell viscoelastic layer to examine the influence of a LVZ on ground surface displacement in response to two different deformation source modes, i.e., instantaneous source deflation during a major eruption and subsequent continuous source inflation due to magma recharge. A LVZ is introduced into the viscoelastic layer by gradually reducing its viscosity towards the centre. The behaviour of the LVZ model quantified by comparison with the behaviour of a uniform viscosity (UNV) model reveals that, for a given LVZ structure, an apparent UNV model that best represents the LVZ model displacement in response to the instantaneous deflation has lower viscosity than that in response to gradual inflation, i.e., the rate-controlling viscosities of the LVZ model are those in the inner and outer parts of the LVZ for the instantaneous source deflation and subsequent continuous inflation, respectively. Such LVZ model behaviour, for a LVZ spatial extent comparable with the imaged low velocity anomaly, explains well the geodetic data in and around Aira Caldera at any stage after the 1914 eruption, as the predominant viscoelastic response changes with time from that to the instantaneous deflation to that to the subsequent continuous inflation. This study highlights the need for interdisciplinary investigations that integrate geodetic and geophysical datasets to better understand volcanic unrest. • Effects of a low viscosity zone (LVZ) beneath Aira Caldera are examined. • LVZ model predicts an apparent viscosity increase in post-eruption period. • Geophysically inferred LVZ well explains geodetic data in and around Aira Caldera. [ABSTRACT FROM AUTHOR]

The deformation of mantle and crustal rocks in response to stress plays a crucial role in the distribution of seismic and volcanic hazards, controlling tectonic processes ranging from continental drift to earthquake triggering. However, the spatial variation of these dynamic properties is poorly understood as they are difficult to measure. We exploited the large stress perturbation incurred by the 2016 earthquake sequence in Kumamoto, Japan, to directly image localized and distributed deformati [ABSTRACT FROM AUTHOR]

Blood stasis syndrome is one of the pathological concepts of Oriental traditional medicine. In Oriental traditional medicine, blood is thought of as not only blood but also as a living component of the body. In fact, blood stasis syndrome is related to not just circulation disorders but dermatological and gynecological and other diseases. In Japan, the concept of blood stasis syndrome is based on the past literature, for instance, Synopsis of Golden Chamber (Jin Kui Yao Lue), etc. There are many signs of this syndrome, such as a dry mouth, fullness of the abdomen and rough skin. However, the levels of importance of these signs had been unclear. Therefore, in order to determine the levels of seriousness, a scoring system of blood stasis syndrome was made based on multivariate analysis by Dr. Terasawa (Terasawa's Blood Stasis Score). Using the scoring system, we have studied blood stasis syndrome mainly related to blood circulation using modern techniques of analysis. From the results, we found that patients with blood stasis syndrome showed hemorheological abnormalities, and an improvement in these abnormalities was shown after administration of removing-blood stasis formulae. Furthermore, we have studied blood stasis syndrome from the point of view of molecular biology. We searched for the specific protein expression in blood stasis syndrome by proteomic analysis, and found no specific protein expression. However, there may be a possibility of developing a diagnostic algorithm for blood stasis by construction of a decision tree. During the past few years, as one of the molecular biological factors affecting blood stasis syndrome, we have been studying hypoxia inducible factor, which is located in the upstream of many genes. Above all, blood stasis syndrome is more than just circulatory deficit but encompasses the pathological concept of constant multilateral change in the living body. [ABSTRACT FROM AUTHOR]

This study examined the aspect of the regulation of velum movement in the transition from the oral to pharyngeal phases of swallowing in relation to changes in the swallowing volume and viscosity by means of measurment of levator veli palatini muscle activity. The subjects were nine normal adults, ranging in age from 24 to 30 years. The swallowing volume was set at 1/4, 1/2 and 1 volume of the optimum volume of green tea for swallowing determined in each subject, and the viscosity was adjusted to 0, 2·0 and 4·6 Pa·s by mixing with thickener. Nine test foods were prepared in total. The electromyographic activity of the levator veli palatini muscle was monitored using bipolar hooked wire electrodes. The levator veli palatini muscle activity was defined as the integrated electromyographic wave. The mean in swallowing each test food was determined in each subject. The levator veli palatini muscle activity increased with the swallowing volume for all subjects ( P < 0·05) and decreased inversely with the viscosity for six subjects ( P < 0·05), but no change with the increase in the viscosity was noted for three subjects. This study clarified the aspect of the regulation of velar movement with regard to the involvement of the levator veli palatini muscle in swallowing activity with changes in the swallowing volume and viscosity. [ABSTRACT FROM AUTHOR]

Abstract: Three historical eruptions of Unzen volcano, Japan, produced two lava flows in 1663 and 1792, and one large lava dome during 1991–1995. Fe–Ti oxides were examined in order to determine the fluidity of the three lavas produced during these events. Magnetic petrology provided constraints on pre- and syn-eruptive conditions of the three eruptions. Phenocrysts that are Ti-poor (ulvöspinel content, ~0.15; ilmenite content, ~0.82) and that have a high Curie temperature (T c =460–480°C) are common within the three lavas, suggesting the existence of a common ~700°C shallow magma chamber with an oxygen fugacity of nickel–nickel oxide+1. Microlites within the three lavas have differing Ti contents, Mg/Mn ratios, and T c, suggesting different eruptive conditions. During the 1663 and 1792 events, relatively large amounts of mafic magma were added to the shallow magma chamber; subsequent magma mixing caused eruption at temperatures around 910–990°C (probably above 1000°C) and 930–1020°C, respectively. In comparison, the 1991–1995 event involved the addition of a relatively small volume of mafic magma to the magma chamber, and the temperature of the erupted magma (860–910°C) was lower than during the other two events. The viscosity of the 1991–1995 lavas is estimated to be higher than that of the two earlier lava flows. In 1663 and 1792, high-temperature magmas with low viscosities ascended quickly from the magma chamber, creating effusive lava flows. In contrast, during the 1991–1995 event, high-viscosity phenocryst-rich low-temperature magmas slowly ascended from the staging magma chamber, forming lava domes rather than being erupted as a lava flow. [Copyright &y& Elsevier]

Abstract: Based on recent results on rock mechanics and geophysical observations, I constructed rheological (strength and viscosity) profiles across the northeastern Japan lithosphere. The profiles well explain patterns of present-day geodetic strain accumulation and shallow seismicity. Experimentally derived flow laws also predict the presence of weak zones by mechanisms likely operated in the lithosphere (e.g., partial melting and shear zone development). The strain localization into weak zones explains the estimates of low viscosity (1019–1020 Pas) from post-seismic creep after a large inland earthquake. The strain localization into weak zones also efficiently accumulates elastic strains at the base of upper seismogenic faults locked during interseismic periods resulting in the reactivation of pre-existing fault systems in the northeastern Japan. [Copyright &y& Elsevier]

In this article, we go in a comparative way, to study the various factors influencing the bearing capacity of the bitumen binders. In fact the factors which will be quoted in the continuation are the loads of circulation and their effects with short, average and long run on the roadways, inevitably inducing the phenomenon of rutting, the composition of materials of the various layers of the roadway, the climatic conditions, and of the geometry of the roadway. Fundamental and well established concepts these factors in Morocco and Japan are mainly described, these fundamental are, for the majority based on the experiment May in Japan a new law of behaviour based on the dissipation of energy was introduced .les factors of traffic and the climatic effects were built-in a system as being probabilistic variables. In this system it is allowed that the tiredness of the bituminous mix is with the outsides and interior bituminous mix. Be factors influencing measurement and the theoretical analysis of clearance is also described briefly. Thus, the development of a new type of asphalt of great viscosity is presented. The idea being to regulate as soon as possible in Japan, permanent deformations due to the effects of the sharp variations of temperatures and by the loads due to the traffic of the heavy trucks which becomes increasingly important. The use of this new type of asphalt made this evidence, reason for which, it would be interesting that a country like Morocco with cities like Marrakech, Rabat, Casablanca and presenting important heat gradients (Marrakech, Rabat, and Casablanca) should be based on the Japanese experiment in order to improve the characteristics of the bituminous mixes. [ABSTRACT FROM AUTHOR]

Seven brands of commercial milk and related products that are available in the Japanese market were investigated. Quantitative descriptive analysis was used to describe 12 sensory properties of the samples, and the position of each sample was displayed by principal component analysis. The sensory descriptors of the samples were correlated with various analytical data by partial least squares regression analysis. Aroma descriptors were correlated with the headspace gas chromatography-mass spectrometry profile. Descriptors of flavor, mouthfeel, and aftertaste were correlated with the results of the physicochemical analysis. Many of the volatile compounds that contributed to aroma attributes, according to the partial least squares loading plot, were in agreement with the influence of volatile compounds shown by previous studies. Lactulose and furosine, as indicators of heating, and viscosity were parameters that influenced flavor, mouthfeel, and aftertaste. In addition, overall aftertaste was significantly related to fat content. [ABSTRACT FROM AUTHOR]

Abstract: The Ryoke Metamorphic Complex of the Mikawa Plateau, Central Japan, contains well-preserved geological and thermal structures formed during Cretaceous high-temperature (high-T) metamorphism. These structures can be explained by a pervasive melt migration model. However, the estimated flux of melt is much higher than that expected for compaction flow of felsic melt. An additional tectonic force and/or melt segregation to network of veins or layers is therefore required. This paper presents the results of numerical modeling of the structural evolution of immiscible viscous fluids under simple-shear deformation, and discusses the role of viscous segregation in enabling pervasive melt flow in hot crust. The results of numerical modeling of simple-shear deformation of immiscible viscous fluids reveal that low-viscosity fluids segregate into lenses and layers. This segregation is a type of viscous segregation that takes place to minimize the dissipation of energy in the system. The rate of energy dissipation is proportional to viscosity. Therefore, this process is expected to occur universally in immiscible viscous fluids with large viscosity contrasts, and is an important process in focusing melt in partially melted rocks. The structures produced by the numerical simulation are similar to those of migmatites. The simulation results suggest that melts distributed randomly in partially melted rock will segregate into lenses or layers with progressive simple-shear deformation. During deformation-enhanced segregation, a melt network will form dynamically. If this process occurs at small to large scales in the hot crust, melts will be effectively transported upward due to buoyancy forces. It is possible that pervasive migmatites at low structural levels within high-T metamorphic complexes may represent “fossil” melt pathways formed by crustal-scale viscous segregation. [Copyright &y& Elsevier]

Quartz-albite-calcite veins in metamorphic rocks of the Sanbagawa belt, Japan, contain sugary mosaics of equant quartz grains <0.01-1.6 mm in size (blocky texture). The quartz crystals show euhed ral to subhedral double-terminated crystal shape, and concentric growth zoning, indicating suspension in aqueous fluid during crystal growth until formation of a framework within the crack. Such a crystallization process is only possible when downward crystal settling is balanced by upward fluid flow. Application of crystal settling theory to the crystal size distributions within the veins reveals an extremely high rate of fluid ascent during blocky vein formation (10-2 to 10-1 m/s) due to the low viscosity of the hydrothermal fluid (~10-4 Pa∙s). Such a high rate of ascent suggests the injection of fluids from mobile hydrofractures within deeper levels of the subduction zone. [ABSTRACT FROM AUTHOR]

We analyzed the microbiota of domestic ropy fermented milk, Caspian Sea yogurt (or ‘kasupikai yohguruto’ in Japanese), circulated in Japan. We collected six varieties from five localities. Lactococcus ( L) lactis ssp. cremoris was isolated from all samples as the dominant strain at levels of 108−109 CFU/g. We show this strain produces an extracellular polysaccharide (EPS) that causes the unique characteristic viscosity of the product. From analysis of the RAPD pattern of 60 bacterial isolates from the six samples, we found that 59 strains from a total of 60 isolates were identical and produced this viscosity. Furthermore, PFGE analysis of representative strains from each sample indicated that the isolates could be classified into four subgroups. This suggests these L. lactis ssp. cremoris strains found in Caspian Sea yogurt may have been slightly mutated during subculture in Japan. In addition, Lactobacillus (L.) sakei ssp. sakei were isolated from three samples; L. plantarum, Gluconoacetobacter sacchari and Acetobacter aceti were isolated from two samples; and L. paracasei, L. kefiri, Leuconostoc ( Leu.) mesenteroides were isolated from one sample. [ABSTRACT FROM AUTHOR]

Abstract: Transitions between effusive and explosive styles of lava dome eruptions are likely accompanied by changes in lava rheology. The common presence of crystals in dome lavas produces a complex non-Newtonian rheology. Thus models of such complex rheology are essential for volcanic eruption models. Here, we have measured the rheology of natural Unzen lavas with a compressive uniaxial press operating at stresses between 1 and 70 MPa and temperatures between 940 and 1010 °C. Crystal-rich Unzen lavas are characterised by two essential rheological features which produce non-Newtonian effects. The first is an instantaneous response of the apparent viscosity to applied stress which requires that the magma be described as a visco-elastic fluid that exhibits shear-thinning. The second effect takes the form of a time-dependence of the viscosity at moderate to high stress (≥10 MPa). In this regime, the apparent viscosity slowly decreases as increasing fracturing of the phenocrysts and the groundmass occurs. Fragmentation of crystals and alignment of crystal fragments are observed to produce flow banding-effects which in turn lower the apparent viscosity of natural dome lavas. Ultimately, deformation may lead to complete rupture of the lava if the stress is sufficient. Cracking thus stands as an important process in natural dome lava rheology. The ubiquitous non-Newtonian rheology of dome lavas, observed experimentally here, needs to be adequately treated in order to generate appropriate eruption models. [Copyright &y& Elsevier]

Abstract: Laboratory measurements of viscosity were done for basalt erupted in 1707 AD from Fuji volcano, Japan, using a concentric cylinder rotational viscometer at temperatures of 1297–1157 °C, 1 atm pressure, and fO2 near the Ni–NiO buffer. On cooling, elongated plagioclase crystals with a mean length/width ratio of ca. 8.5 appeared at 1237 °C, followed by olivine at 1157 °C. At progressively lower temperatures, the total crystal volume fraction increased monotonously to ca. 0.25; viscosity increased from 38.9 to 765 Pa s at a shear strain rate of 1 s−1. This basalt magma behaves as a Newtonian fluid at temperatures greater than 1217 °C, but shear-thinning behavior occurs at temperatures less than 1197 °C because of the suspended plagioclase crystals. This behavior is well approximated as a power law fluid. At the onset of shear thinning, the crystal volume fraction was between 0.06 and 0.13, which is attributed to the pronounced lath-shape of plagioclase crystals. The relative viscosity increases monotonously with increase of crystal volume fraction at a constant shear strain rate, and with decrease of shear strain rate at a constant crystal volume fraction. A modified form of the Krieger–Dougherty equation is introduced herein. It enables us to describe the dependencies of relative viscosity on both the crystal volume fraction and shear strain rate, and consequently the onset of shear-thinning behavior. [Copyright &y& Elsevier]

Abstract: We carried out viscosity measurements and sampling of a crystal suspension derived from alkali olivine basalt from the Matsuura district, SW Japan, at subliquidus temperatures from 1230 °C to 1140 °C under 1 atm with NNO oxygen buffered conditions. Viscosity increased from 31 to 1235 Pa s with a decrease in temperature from 1230 to 1140 °C. On cooling, olivine first appeared at 1210 °C, followed by plagioclase at 1170 °C. The crystal content of the sample attained 31 vol.% at 1140 °C (plagioclase 22%, olivine 9%). Non-Newtonian behaviors, including thixotropy and shear thinning, were pronounced in the presence of tabular plagioclase crystals. The cause of such behavior is discussed in relation to shear-induced changes in melt–crystal textures. Relative viscosities, η r (= η s / η m, where η s and η m are the viscosities of the suspension and the melt, respectively), were obtained by calculating melt viscosities from the melt composition and temperature at 1 atm using the equation proposed by Giordano and Dingwell [Giordano, D., Dingwell, D.B., 2003. Non-Arrhenian multicomponent melt viscosity: a model. Earth and Planetary Science Letters, 208, 337–349.]. The obtained relative viscosities are generally consistent with the Einstein–Roscoe relation, which represents η r for suspensions that contain equant and equigranular crystals, even though the crystal suspension analyzed in the present experiments contained tabular plagioclase and granular olivine of various grain sizes. This consistency is attributed to the fact that the effect of crystal shape was counterbalanced by the effect of the dispersion of crystal size. The applicability of the Einstein–Roscoe equation with respect to crystal shape is discussed on the basis of the present experimental results. Our experiments and those of Sato [Sato, H., 2005. Viscosity measurement of subliquidus magmas: 1707 basalt of Fuji volcano. Journal of Mineralogical and Petrological Sciences, 100, 133–142.] show that the relationship between relative viscosity and crystal fraction is consistent with the Einstein–Roscoe relationship for axial ratios that are smaller than the critical value of 4–6.5, but discrepancies occur for higher ratios. [Copyright &y& Elsevier]

One hundred and sixty-seven rice varieties/laudraces from 23 different rice-growing countries were used for studying the relationship between the amylose content (AC %) and paste viscosity parameters (RVU) through Pearson correlation. AC and paste viscosity parameters were measured using Auto Analyser and Rapid Visco Analysers respectively. Based on all five RVA pasting properties, i.e. peak viscosity (PV), minimum viscosity (MV), breakdown (BD), final viscosity (FV) and setback (SB), the simple paired t-test (at P = 0.05) was carried out to identify varieties that showed non-significant differences (similar) from the check variety, separately for each of the four AC groups, e.g. Waxy rice AC (0–8%, n = 21) –‘IR29’ (Philippines); Low AC (8.1–16%, n = 58) –‘Koshihikari’ (Japan); Intermediate AC (16.1–24%, n = 64) –‘Local Sadri’ (Iran); high AC (>24.1%, n = 24) –‘Kasalath’ (India). Significant variation among the rice varieties for AC and pasting properties were observed. Means of the AC and the viscosity parameters including PV, MV, BD, FV and SB were 15.8, 416.1, 180.3, 235.8, 380.9 and 200.6 RVU respectively. Significant correlations existed between AC and paste viscosity parameters at AC group level. The paste viscosity parameters, i.e. PV, BD and SB are important within an AC group as far as cooking quality is concerned. In the low AC group, ‘Koshihikari’ (check) was most preferred by Japanese consumers, which was used for identifying 16 varieties that showed non-significant differences for pasting properties with it. Some of the important Japanese varieties were ‘Todorokiwase’, ‘Owarihatamochi’, ‘Sasanishiki’, ‘Reimei’ and ‘Kinuhikari’. These varieties had good cooking quality with low AC, high PV and BD with low SB. In contrast, the Iranian cultivar ‘Local Sadri’ with good cooking quality had intermediate levels of AC and SB while recording high PV and BD. The varietal diversity for pasting properties available within each AC group may allow the breeder to make effective selections for improving the cooking quality according to consumer choice. [ABSTRACT FROM AUTHOR]

The Miyazaki Plain, eastern part of Kyushu, Japan, is characterized by both significant negative gravity anomalies and aseismic crustal uplifting (∼1 mm/year) in the Late Pleistocene and Holocene. We examine the relationship between these two phenomena, which may provide important constraints on the interaction between the collision and/or subduction of the Kyushu-Palau Ridge and the forearc. We estimate the mass deficiency below 11-km depth by using the gravity anomalies and P-wave velocity structure of the upper crust. The onset of the load accumulation, 0.5–0.4 Ma, is inferred from the movement of the fluvial terraces considering the tephrochronology. The loading history is assumed to be a linear function of time. We evaluate the crustal rebound by assuming a viscoelastic plate deformation with an underplating load existing at 20- or 30-km depth. The predicted crustal movement for models with a lithospheric (crustal) viscosity of 1023–1024 Pa s can explain the observed altitudes of the shoreline of the marine terraces formed at the Last Interglacial of about 125 kyr BP and the middle Holocene of 5–6 kyr BP. Although we cannot restrict the origin of the buoyant body, the subduction of the Kyushu-Palau Ridge, remnant arc associated with back-arc opening of the Shikoku Basin, may be related to the buoyancy for the uplifting region examined here. On the other hand, the buoyant body off the Miyazaki Plain probably plays an important role in the interaction between the subducting oceanic slab and the overriding forearc crust. Thus, the observed lateral variation of the interplate coupling on the convergent boundary along the Nankai Trough may be attributed to the existence of the buoyant body. [Copyright &y& Elsevier]

The article presents a rheological study on the flow properties of polyaddition-type silicone impression materials in Japan. The study found out that there are little additions of synthetic silica (micro filler) in experimental pastes which made a flow property having a yield value and was effective in working. The study suggests a direction in manufacturing impression materials toward including superior characteristics that had low velocity and was easy to mix in working.

We have reassessed the mode of advance of lava erupted in the 1990s from Unzen Fugen-dake Volcano in northwestern Kyushu, Japan. The apparent viscosity of Unzen lava had been estimated to be 0.9–4.2 × 1010 Pa s from the observed lava surface velocity in 1991, using Jeffreys model, based on the assumption that the lava was a Newtonian or Bingham fluid. In contrast, the viscosity of synthetic groundmass glass derived from Unzen lava had been measured in the laboratory at expected lava temperatures (780 °C–880 °C) to be 1011–1013 Pa s, considerably higher than the viscosity based on field observation. If the suspension effect of crystals is taken into consideration for groundmass glass, several orders of magnitude higher viscosity than observed should be expected for Unzen lava. To seek the source of the disparity in viscosity estimates, we first performed uniaxial-compression viscometry on natural Unzen lava samples collected in 1991 and thereby confirmed that the lava viscosity was actually higher than determined by field observations and equal to or higher than the fluid–solid threshold viscosity (1012 Pa s). This suggests that the observational viscosity had been underestimated. From reanalysis of the lava migration using video and photographs, contemporaneous with the field-based viscosity estimation, we found that the lava behavior was far from that of a fluid. Apparently, the lava lobe lost its fluidity at the flow front and instead advanced rigidly, thereby indicating that the application of Jeffreys model had incorrectly led us to underestimate viscosity. Although we used only the 1991 lava samples and image data, we infer that rigid migration was common for all exogenous lava lobes during the 1991–1995 activity. Our comparative study demonstrates that cooled and/or degassed lavas could show higher mobility than expected from experiment- or model-based viscosity. Apparently this occurs when the frictional force is smaller between lobe base and underlying slope than the viscous resistance inherent in lava. • Experimental viscosity of Unzen lava was much higher than observational viscosity. • Video analysis revealed that Unzen lava did not flow but migrated rigidly. • Assumption that lava migrates by flowing misled us to viscosity underestimation. [ABSTRACT FROM AUTHOR]

Bolus texture is a key factor for safe swallowing in patients with dysphagia since an improper texture may result in aspiration and/or pharyngeal residue. This article discusses swallowing bolus texture from two key aspects: the textural change of solid food by mastication and the current standardized definition of food texture in Japan. When swallowing a liquid bolus, the texture is mostly maintained from ingestion to swallow onset. For solid food, however, the food is crushed by chewing and mixed with saliva before swallowing; the texture of the ingested food is modified to an easily swallowable form at swallow onset by mastication. Understanding the mechanism of mastication and its assessment are therefore important in deciding the proper diet for dysphagic patients. As standardized criteria for classifying the texture of food and liquid are essential as well, this report also describes the Japanese Dysphagia Diet 2013 that is commonly used as the standardized index for dysphagic diets in Japan.

In Japan, the viscosity of thickened liquids is different among hospitals and nursing homes. In order to standardize viscosity of thickened liquids, the dysphagia diet committee of the Japanese Society of Dysphagia Rehabilitation developed the Japanese Dysphagia Diet 2013 (JDD2013). To decide on a definition of thickened liquids, the committee reviewed categories from other countries. Especially, the criteria of the USA and Australia were used as references. The definition had three levels: mildly thick, moderately thick, and extremely thick. Then a sensory evaluation by health care workers was carried out to decide the viscosity range of each level, and a draft document was made. After collecting public comments, follow-up experiments using thickened water with thickeners using xanthan gum were performed, and the JDD2013 (Thickened Liquid) was determined. The JDD2013 (Thickened Liquid) evaluated the drinking properties, visual properties, and viscosity values of each level. The shear rate of 50 s -1 was adopted to measure the viscosity with a cone and plate type viscometer to duplicate the measurement criteria used by the USA. We also set the values of the JDD2013 with the Line Spread Test to promote the use of guidelines in clinical practice. We believe the JDD2013 standards help hospitals and other settings that care for people with dysphagia to use the same thickness level and the same labels. In the future, the JDD2013 levels will be compared with new international guidelines to help with international understanding of the JDD2013 levels.

Background & Aims: The initial complications associated with infusion of enteral nutrition (EN) for clinical and nutritional care are vomiting, aspiration pneumonia, and diarrhea. There are many recommendations to prevent these complications. A novel method involving a viscosity-regulating pectin solution has been demonstrated. In Japan, this method along with the other so-called "semi-solid EN" approaches has been widely used in practice. However, there has been no randomized clinical trial to prove the efficiency and safety of a viscosity-regulating pectin solution in EN management. Therefore, we planned and initiated a multicenter randomized controlled trial to determine the efficiency and safety., Methods: This study included 34 patients from 7 medical institutions who participated. Institutional review board (IRB) approval was obtained from all participating institutions. Patients who required EN management were enrolled and randomly assigned to the viscosity regulation of enteral feeding (VREF) group and control group. The VREF group (n = 15) was managed with the addition of a viscosity-regulating pectin solution. The control group (n = 12) was managed with conventional EN administration, usually in a gradual step-up method. Daily clinical symptoms of pneumonia, fever, vomiting, and diarrhea; defecation frequency; and stool form were observed in the 2 week trial period. The dose of EN and duration of infusion were also examined., Results: A favorable trend for clinical symptoms was noticed in the VREF group. No significant differences were observed in episodes of pneumonia, fever, vomiting, and diarrhea between the 2 groups. An apparent reduction in infusion duration and hardening of stool form were noted in the VREF group., Conclusions: The novel method involving a viscosity-regulating pectin solution with EN administration can be clinically performed safely and efficiently, similar to the conventional method. Moreover, there were benefits, such as improvement in stool form, a short time for EN infusion, and a reduction in vomiting episodes, with the use of the novel method. This indicates some potential advantages in the quality of life among patients receiving this novel method., (Copyright © 2017 European Society for Clinical Nutrition and Metabolism. Published by Elsevier Ltd. All rights reserved.)

Background: Administration of thickened enteral formula (TEF) through a percutaneous endoscopic gastrostomy (PEG) tube is becoming a common practice in Japan to prevent enteral nutrition (EN)-related complications. However, what constitutes an adequate viscosity of TEF remains unclear. The aim of this study was to examine the clinical effects of TEFs with different viscosities administered through PEG., Methods: The subjects were 50 patients admitted to a single institution who underwent PEG placement. Viscosities of TEFs frequently administered to the patients were measured, and EN-related complications, nutrition intakes, and clinical outcomes were compared between high- and medium-viscosity TEFs during the first 2 weeks after TEF feeding initiation., Results: The measured viscosities of high- and medium-viscosity TEFs were 10,382 ± 931 and 3492 ± 296 mPa·s, respectively. Protein and fluid intakes with TEF were significantly less in the high-viscosity group. There was no significant difference in EN-related complications, energy intakes, or clinical outcomes between high- and medium-viscosity TEFs., Conclusion: In this study, high-viscosity TEFs showed no statistical difference in either EN-related complications or clinical outcomes, in comparison with medium-viscosity TEF.

Lepidoperan silks provide a superb opportunity for comparative studies of spinning and fiber characteristics. Comparing the four species, Bombyx mori (China), Actias selene (India), Antheraea yamamai (Japan), Gonometa postica (Africa), allows us to examine differences on the family, species, and race levels. Measured rheological properties were consistent with phylogenetic relationships and in the context of resource allocation and gland morphology. We propose that the thorough domestication of the mulberry silkworm B. mori for high silk yield has resulted in a compensatory optimization for spinning efficiency. This is in stark contrast to the wild silkworms, where Saturnids appear to minimize their energetic input toward silk output and G. postica seems to balance both. We conclude that comparative studies provide valuable baseline information for future biomimetic applications and modeling, as well as illuminating biologically important details of silk processing., (Copyright © 2011 Wiley Periodicals, Inc.)

We previously suggested that the consumption of natto and viscous vegetables as part of a Japanese-style meal based on white rice (WR) reduced postprandial glucose and insulin levels in healthy subjects. The aim of the present study was to assess whether a single breakfast of natto and viscous vegetables or the same breakfast consumed for 2 weeks could improve glucose control, insulin sensitivity, lipid metabolism and oxidative stress in overweight subjects with impaired glucose tolerance (IGT). A total of eleven free-living subjects with IGT followed a randomised, crossover breakfast intervention for 2 weeks. The test meal included boiled WR with natto (viscous fermented soyabeans), Japanese yam and okra. The control meal included WR with non-viscous boiled soyabeans, potatoes and broccoli. Both meals contained comparable amounts of carbohydrate, fat, protein and fibre. The test meal reduced acute glucose and insulin responses compared to the control meal in the study participants. Insulin sensitivity was assessed using the composite insulin sensitivity index (CISI) after both the test and control meal periods. The test meal resulted in improvements in CISI compared to the baseline, whereas no significant changes were observed after the control meal period. Serum levels of both total and LDL-cholesterol were assessed before and after the test meal period and found to decrease significantly. There was also a tendency towards reduced serum malondialdehyde-modified LDL and N(ɛ)-carboxymethyllysine. No differences were observed in the measures of chronic glycaemic control. Thus, we conclude that a breakfast of natto and viscous vegetables consumed for 2 weeks improves insulin sensitivity, serum lipid and oxidative stress.

The purpose of this research was to study the functional differences between straight grade (75% extraction rate) and patent (60% extraction rate) flour blends from 28 genetically pure soft white and club wheat grain lots, as evidenced by variation in sugar snap cookie and Japanese sponge cake quality. Functional differences were examined relative to arabinoxylan content, protein content, and oxidative cross-linking potential of flour slurries. Oxidative cross-linking measurements were obtained on flour slurries with a low shear Bostwick consistometer and considered endogenous oxidative cross-linking potential (water alone) or enhanced oxidative cross-linking potential (with added hydrogen peroxide-peroxidase). A 2-way ANOVA indicated that flour blend was the greater source of variation compared to grain lot for all response variables except water-extractable arabinoxylan content. Patent flours produced larger sugar snap cookies and Japanese sponge cakes, and contained significantly less total and water-unextractable arabinoxylans, protein, and ash than did straight grade flours. Patent flours produced more viscous slurries for endogenous and enhanced cross-linking measurements compared to the straight grade flours. The functional differences between patent and straight grade flours appear to be related to the particular mill streams that were utilized in the formulation of the 2 flour blends and compositional differences among those streams., (Journal of Food Science © 2011 Institute of Food Technologists® No claim to original US government works.)

Purpose: Three products can be used in Japan for the reconstitution of cytotoxic agents: PhaSeal, Chemo CLAVE and Chemo Mini Spike (CMS). The low preparation volume may be affected by residual-related volume in their devices. In this study, the residual-related error in their devices was examined and compared., Method: The blank of each component of these devices was weighed using a precision electric balance. After ejecting distilled water (DW) for injection, each was weighed again with the balance. In addition, for etoposide in the cases of PhaSeal and Chemo CLAVE, the components of the devices were similarly weighed., Result: The weight gains of each device after ejecting DW were as follows: CMS-V (440 mg) greater than the combined components of Chemo CLAVE (128-171 mg)/CMS-MT (123 mg) greater than the combined components of PhaSeal (13-56 mg). For etoposide, the weight gains of PhaSeal (208 mg) and Chemo CLAVE (223 mg) showed no significant difference. The priming volume of each device was calculated from the specific gravity of water. The residual-related volume was 'CMS-V > Chemo CLAVE, CMS-MT > PhaSeal', although this was very slight in actual situations., Conclusion: The residual-related volume was marked in its low preparation volume. In water-soluble drugs, the residual volume of PhaSeal was lowest of the devices in this study, but in viscous drugs, such as etoposide, the residual volume of PhaSeal was almost identical to Chemo CLAVE; that is, the residual volume of these devices was affected by the solution property. The residual-related volume in the devices will lead to errors; therefore, residual-related errors need to be considered in the use of these devices.

An analysis of static occlusion including occlusal force and occlusal contact area in intercuspal position may be helpful but a dynamic analysis of occlusion should be regarded as more important for analyzing the stomatognathic system. Anthropological research has shown that the Japanese and the Mongolian populations share morphological and genetic similarities, although their dietary lives are not the same. The purpose of this study was to evaluate the relationship between environmental factors such as dietary life and stomatognathic function with a dynamic analysis of physiological tooth displacement. Ten clinically healthy subjects were recruited (mean age 24.8 +/- 1.0 years). The subjects were divided into two groups 1) Mongolian group: five Mongolians grown with a more or less natural texture diet and 2) Japanese group: five Japanese grown with a relatively soft diet. The displacement of the upper left first molar was measured during function using a three-dimensional tooth displacement transducer Type M-3. The tooth displacement in the Japanese group occurred mostly in an apicopalatal direction, but intruded basically parallel to the tooth axis in the Mongolian group. The stress-strain curve revealed that elastic socket deformation and viscous elements were more pronounced in the Japanese group. It was concluded that environmental factors such as dietary life could influence tooth displacement during function.

This study aimed to investigate the effects of different sensory-evaluated food textures on masticatory movements, and to identify meaningful factors that correspond to different food textures. Masticatory movements of three healthy subjects were evaluated with a jaw movement tracking device using five different test foods: almond, hard and light rice crackers, apple, and chewing gum. The movements of the incisor point, working and non-working condyle and the entire mandible at the occlusal phase in the horizontal plane were analyzed. For harder foods, the incisor entered the intercuspal position from a rear and lateral, the working condyle showed anterior and noticeable medial movements as the entire mandible translated posteriorly and medially. For soft foods, the incisor movements were nearly coincidental with the lateral border movements, and the mandible rotated towards the inner side near the working condyle. Although the overall paths of the mandibular movements are individually different, it appeared that jaw movement at the final closure is particular to the food texture. From the standpoint of mandibular movements, it is suggested that masticatory movements during the occlusal phase in the horizontal plane is useful for revealing the relationship between mandibular movements and food textures that were evaluated with onomatopoetic words.

The thermal and viscoelastic properties of commercial inlay waxes were investigated by measurements of JIS (Japanese Industrial Standard), differential thermal analysis, dilatometry and dynamic viscoelasticity. The crystal transition from orthorhombic to hexagonal caused by paraffin was observed in inlay waxes. The thermal expansion of waxes was influenced by crystal transition temperature. The cooling shrinkage of internal wax pattern is smaller in wax having larger expansion from 25 degrees C to 37 degrees C. The viscoelastic properties of inlay waxes shifted to low temperature region with decreasing in crystal transition temperature. The various properties of inlay waxes greatly changed at temperature of peak for loss tangent. There were some problems on measurement methods of JIS and the reexamination of thermal expansion and flow was suggested. Commercial inlay waxes, respectively, have various different properties, but from these results the qualities of waxes can not be determined so it's necessary to choose a suitable wax according to various conditions.