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This study constructs a model to represent the strain–stress field surrounding a splay fault and demonstrates the accumulation processes of both strain and stress around the splay fault. We consider the case of multiple fault dislocations, construct the model as a function of the effective viscosity in the media, and investigate the influence of the effective viscosity on the strain and stress accumulation patterns. The results show that the strain and stress tend to accumulate in the splay fault and the subducting oceanic crust, and the rate of accumulation varies with the effective viscosity. The accumulation and relaxation of strain and stress are simultaneous, and the slower the effective viscosity, the slower the accumulation rate. We discuss the relationship between the splay faults, fluid, and intraslab earthquakes. Finally, the possibility that effective viscosity may contribute to the mode of occurrence of intraslab earthquakes at the Hikurangi subduction margin is discussed. Plain Language Summary: We construct a simple model to explain the evolution of strain and stress over time in a subduction margin. The model constructed in this study is the case where a fault branches from a plate boundary. We investigate the influence of the effective viscosity of its constituents on the temporal evolution of strain and stress. The results show that the rate of strain and stress accumulation varies with the effective viscosity. Our result may suggests the influence of the effective viscosity on the source distribution of the microearthquakes observed at the Hikurangi subduction margin. Key Points: Temporal evolution of strain and stress caused by the dislocation of tri‐materials with different effective viscosities is calculatedStrain and stress accumulation rate depends on the effective viscosityStrain and stress accumulated at the multiple fault edge strongly influence the stress perturbations in the subducting oceanic crust [ABSTRACT FROM AUTHOR]

Isolating the source of nontidal oceanographic noise in seafloor pressure data is critical for improving the use of these data for seafloor geodetic applications. Residuals between nearby bottom pressure records have typically been used to remove the nontidal components, as these are largely common‐mode. To evaluate the similarities between pairs of observed bottom pressure records at a range of water depths, we calculate the standard deviations of the time series of residuals between data from all site pairs, installed in the Hikurangi subduction zone offshore New Zealand. We find that the magnitude of the standard deviation depends more on relative water depth than the distance between sites. This confirms the result of previous studies from Cascadia that nontidal components are more similar along isobaths even if the distance between sites is large. Furthermore, in order to reduce noises, the required depth difference between site pairs also varies with site depths. Plain Language Summary: Coherent signals of ocean bottom pressure are observed along common water depths within an ocean bottom pressure array offshore New Zealand. We statistically evaluated the similarity of the seafloor pressure collected in 2014 offshore the North Island's east coast, where the Pacific Plate dives or "subducts" along the Hikurangi subduction zone beneath the North Island. This is important for removal of noise caused by oceanographic processes, which must be done to detect centimeter‐level vertical movement of the seafloor crust during slow slip events using seafloor pressure records. We measured the similarity of pairs of seafloor pressure records at a range of water depths. Similar to previous studies offshore the Cascadia subduction zone, our results confirm that seafloor pressure records from similar depths (but at large horizontal distances from each other) can be used effectively to reduce oceanographic noise in sea floor pressure data to reveal the seafloor crustal deformation. Key Points: The similarity of the nontidal components of bottom pressure varies with relative water depth, rather than distance between sitesBottom pressure data show that reference sites at similar depths will optimize oceanographic noise removal for seafloor geodetic studiesOceanographic models with baroclinicity represent the observed depth dependence of the nontidal variations better than barotropic models [ABSTRACT FROM AUTHOR]

In this paper, a new high-pressure viscosity measurement system using a capillary method is reported. In this system, two pressure balances are used to generate stable pressure and flow field in the capillary. The volumetric flow rate was measured by calculating the change in the piston fall rate. To check the effectiveness of the method, the viscosity of bis(2-ethylhexyl) sebacate was measured at pressures of up to 200 MPa. Differential pressure and volumetric flow rate had a linear relationship at all temperature and pressure conditions, indicating that the Hagen–Poiseuille law can be applied in this method. The viscosity–pressure dependence is in agreement with other published reports. Thus, we confirmed that the newly developed high-pressure viscosity measurement system can accurately evaluate the pressure dependence of viscosity. [ABSTRACT FROM AUTHOR]

Ocean bottom pressure (OBP) observations are a powerful tool for determining vertical crustal displacements, especially due to earthquakes and slow earthquakes, with centimeter‐level resolution. In these studies, removal of oceanographic noise (tens of centimeters) is required to identify centimeter‐level crustal deformation. We undertake barotropic modeling to remove oceanographic signals from data from an OBP array deployed offshore New Zealand in 2014/2015. We show that removing the nontidal component calculated from a barotropic ocean model reduces the variance in the data by about 66% and provides a feasible means to resolve pressure changes due to crustal deformation during the slow slip events. We also discuss the vertical displacements from slow slip events that occurred in late September to mid‐October 2014, and we outline our procedure for processing OBP data. Plain Language Summary: We developed a new method for determining pressure changes due to slow slip events (SSEs) on offshore subduction plate boundaries by using information from the ocean bottom pressure records and numerical simulation. We use an oceanographic model to correct the seafloor pressure data for oceanographic signals, so that centimeter‐level vertical deformation of the seafloor during the SSEs can be isolated. We show that this method can be used to identify SSEs that occurred off the coast of New Zealand in 2014. Our results indicate that our ocean model can be a useful tool to use ocean bottom absolute pressure gauge data to resolve crustal deformation. Key Points: The oceanographic corrections from our model help to reduce noise in ocean bottom pressure data recorded during slow slip eventWe show a barotropic oceanographic model can be used to reduce the variance in seafloor pressure measurements by about 66%Our oceanographic model is particularly valuable for the shallower‐water sites [ABSTRACT FROM AUTHOR]

Nanoparticle fluidization was studied in a centrifugal fluidized bed (CenFB) with variable gravitational acceleration (Gg) conditions. Agglomerate size variation in CenFB nanoparticles (7 nm) was examined with G and fluidization time. With increasing fluidization time, the agglomerate size was found to decrease and reach an equilibrium value after several hours. Higher G reduced agglomerate size. To elucidate these phenomena, a comprehensive model was developed based on the energy balance model with respect to energy consumption for disintegration of agglomerates. Experimental results showed good agreement with the proposed model. Effects of high G on agglomerate fluidization are clarified as follows. The critical minimum size of agglomerates, which is the agglomerate size estimated by the force balance model, is reduced by high G. Attainable energy for disintegration of agglomerates is increased, leading to decreased agglomerate size. [ABSTRACT FROM AUTHOR]

We previously reported that μ-oxo N,N'-bis(salicylidene)ethylenediamine iron [Fe(Salen)], a magnetic organic compound, has direct anti-tumor activity, and generates heat in an alternating magnetic field (AMF). We showed that Fe(Salen) nanoparticles are useful for combined hyperthermia-chemotherapy of tongue cancer. Here, we have examined the effect of Fe(Salen) on human glioblastoma (GB). Fe(Salen) showed in vitro anti-tumor activity towards several human GB cell lines. It inhibited cell proliferation, and its apoptosis-inducing activity was greater than that of clinically used drugs. Fe(Salen) also showed in vivo anti-tumor activity in the mouse brain. We evaluated the drug distribution and systemic side effects of intracerebrally injected Fe(Salen) nanoparticles in rats. Further, to examine whether hyperthermia, which was induced by exposing Fe(Salen) nanoparticles to AMF, enhanced the intrinsic anti-tumor effect of Fe(Salen), we used a mouse model grafted with U251 cells on the left leg. Fe(Salen), BCNU, or normal saline was injected into the tumor in the presence or absence of AMF exposure. The combination of Fe(Salen) injection and AMF exposure showed a greater anti-tumor effect than did either Fe(Salen) or BCNU alone. Our results indicate that hyperthermia and chemotherapy with single-drug nanoparticles could be done for GB treatment. [ABSTRACT FROM AUTHOR]