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Reducing dimensionality can induce profound modifications to the physical properties of a system. In two-dimensional TaS2 and TaSe2, the charge-density wave phase accompanies a Mott transition, thus realizing the strongly correlated insulating state. However, this scenario deviates from TaTe2 due to p–d hybridization, resulting in a substantial contribution of Te 5p at the Fermi level. Here, we show that, differently from the Mott insulating phase of its sister compounds, bilayer TaTe2 hosts a power-law (V-shaped) gap at the Fermi level reminiscent of a Coulomb gap. It suggests the possible role of unscreened long-range Coulomb interactions emerging in lowered dimensions, potentially coupled with a disordered short-range charge-density wave. Our findings reveal the importance of long-range interactions sensitive to interlayer screening, providing another venue for the interplay of complex quantum phenomena in two-dimensional materials. [ABSTRACT FROM AUTHOR]

We have already reported some electroplated magnetic films using aqueous solutions. In the present study, we proposed a fabrication process for electroplated soft magnetic films (Ni films) using gel electrolytes. We added gelatin to the plating baths and confirmed that adding 22 g/L of gelatin enabled us to obtain gel electrolytes. Using the gel electrolytes, we electroplated Ni films and evaluated their structural and magnetic properties. From the evaluation of magnetic properties, we confirmed spontaneous magnetization of the Ni films prepared from the gel electrolyte. For obtaining thick Ni films (>1 μm), we investigated stirring the gel electrolyte during plating. As a result, we found that stirring increased the thickness, and our result suggests that stirring the gel electrolyte is useful to increase the deposition rate. In our experimental conditions, the deposition rate of the plating process was ∼0.25 μm/min. From XRD analysis, the structure of Ni films for gel electrolytes was oriented in the fcc (220) plane and slightly different from that for liquid electrolytes. From these results, we found that soft magnetic films could be obtained from the gel electrolyte and that gel plating is one of the attractive fabrication processes of the thick films. [ABSTRACT FROM AUTHOR]

We recently reported the electroplating of Fe-Pt thick films using plating baths with varying concentrations of NaCl, suggesting the potential for coercivity enhancement by Na ions. In the present study, our focus shifted to not Na ions but Cl ones, and we investigated the effect of the Cl ions on the crystal structures and magnetic properties of electroplated Fe-Pt films. With the increasing concentration of Cl ions, the coercivity of the films decreased. Furthermore, XRD analysis suggested that the Cl ions in the plating baths prevent the L10 ordering of the Fe-Pt crystalline phase, leading us to conclude that a Cl-free bath is favorable for preparing Fe-Pt thick-film magnets with high coercivity. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the perioperative and postoperative incidence of deep vein thrombosis (DVT) and validate the effectiveness of our own preventive treatment protocol for venous thromboembolism (VTE) occurrence in lower extremity arthroplasty patients. The subjects were 1,054 patients (mean age: 74.3 years) who underwent total hip arthroplasty (THA) or total knee arthroplasty (TKA) at our institutions between April 2014 and March 2017. We examined the frequencies of pre- and post-operative DVT by lower extremity Doppler images, and the incidence rate at proximal or distal regions as well as that according to preoperative DVT status were evaluated. Preoperative DVT was detected in 6.5% (69 cases) of our cohort and those were located 1.4% (15 cases) at proximal and 5.1% (54 cases) at distal regions. A significantly higher rate of postoperative DVT development was observed in preoperative DVT+ THA patients (P = 0.0075), but not in TKA patients only with a higher tendency (P = 0.56). The overall incidence of DVT up to 2 weeks after surgeries was 27.3% (288 cases); however, the rate in proximal femur regions was suppressed to 2.8% (30 cases), and there was no symptomatic pulmonary thromboembolism (PTE) case. The results demonstrated the importance of regular Doppler examination for early detection of postoperative DVT occurrence and the following immediate treatment initiation. Our own VTE preventive treatment protocol could reduce the development of proximal DVT, and the periodic monitoring as well as prompt treatment might prevent the fatal PTE. osteoarthritis (OA), rheumatoid arthritis (RA). [ABSTRACT FROM AUTHOR]

Although tapered-wedge short stem has been widely employed with its availability for minimally invasive surgeries in total hip arthroplasty (THA), post-operative stress shielding matter remains unresolved in cementless procedures. This study aimed to clarify the most optimal femoral canal contact regions of the stem design taking stress shielding incidence into consideration. This investigation included 60 joints from 60 patients (mean age at operation: 65.9 years), of which follow-up duration after primary THA had been more than 2 years. Frequencies of spot welds, subsidence, and stress shielding were examined 2 years after surgery. The most suitable femoral canal contact regions were evaluated by plain radiograph (2D) and 3D-computed tomography analyses according to Nakata's division for fitting manners. Spot welds were observed in 38 cases (63.3%), and no subsidence case was seen. Respective number of stress shielding cases, based on Engh's classification, categorized as degree 0, 1, and 2, were 2 (3.3%), 31 (51.7%), and 27 (45.0%), while no cases for degree 3 or 4 were found. When assessed by 3D fitting analysis, 27 cases of stress shielding degree 2 were constituted by 13/42 cases of mediolateral (ML) fit, 2/4 cases of flare fit, and 12/14 cases of multi point fit. In 42 cases of ML fitting, stem contact rate of the most proximedial region in stress shielding degree 0 and 1 was significantly higher compared to stress shielding degree 2 cases. Meanwhile, the rates of distal regions were significantly lower or absent in stress shielding degree 0 and 1 cases. The initial fixation of this stem design was very good in our cohort regardless of fitting manners. This study successfully revealed that ML fitting with femoral component, especially the most proximedial calcar site restricted fitting, would be optimal for reducing stress shielding occurrence in cementless short, tapered-wedge stem THA. Thus, the ideal stem contact region should be considered during THA procedures in light of the reduction of stress shielding development. [ABSTRACT FROM AUTHOR]

We have prepared Fe-Ni-system bilayer ribbons with different magnetostriction (compositions) and investigated the improvement of soft magnetic properties using the magnetoelastic effect. A toroidal core with D = 10 mm was made from the Fe6Ni94/Fe56Ni44 bilayer ribbon, and the B-H loop of the core was measured. The shape of the hysteresis loop dramatically changed depending on the inner layer (inner magnetic phase). This result indicates that the direction of the anisotropy induced by bending stress was changed depending on the inner layer. The slope of the B-H loop and coercivity reduced when the Fe56Ni44 layer was on the inner side. From the experimental results, we found that domain rotation was dominant for the magnetization process. Consequently, the increase in the coercivity over frequency could be suppressed by controlling the magnetization process. From these results, we found that a thin bilayer ribbon with positive and negative magnetostriction constant is an attractive material for reducing iron losses under high frequency. [ABSTRACT FROM AUTHOR]

In geotechnical engineering, fiber reinforcement for improving the stability and strength of soils is of considerable interest. According to previous studies, fibers enhance compressive strength significantly, whereas the contribution of fibers in extension is limited. However, this phenomenon has not been analyzed comprehensively. Therefore, conventional triaxial compression and extension tests were conducted under both drained and undrained conditions on fiber-reinforced sand specimens to elucidate the influence of fibers on tensile strength. The compression behavior was significantly influenced by the presence of fibers and confining pressure, independent of the drainage conditions. However, in the extension experiments, the properties of the fiber-reinforced sand under drained conditions differed from those of unreinforced specimens. The tensile strength of the fiber-reinforced sand was relatively enhanced under undrained conditions. Both unreinforced and fiber-reinforced sands experienced deformation throughout the entire height of the specimen, and their central regions bulged under loading conditions. With an increase in confining pressure under unloading conditions, the unreinforced sand specimen developed a double “necking” shear band in the center with more pronounced strain localization. In contrast, the failure modes of fiber-reinforced sand in drained conditions were characterized by strain localization and shear bands transferred to the bottom part of specimens. According to the experimental results and their repeatability, a conventional triaxial extension test may be insufficient to evaluate tensile strength accurately. In addition, a possible explanation for the fiber-sand interaction mechanism has been proposed based on the obtained results and failure mode analysis. [ABSTRACT FROM AUTHOR]

A proximity effect at a van der Waals (vdW) interface enables creation of an emergent quantum electronic ground state. Here we demonstrate that an originally superconducting two-dimensional (2D) NbSe2 forms a ferromagnetic ground state with spontaneous spin polarization at a vdW interface with a 2D ferromagnet V5Se8. We investigated the anomalous Hall effect (AHE) of the NbSe2/V5Se8 magnetic vdW heterostructures, and found that the sign of the AHE was reversed as the number of the V5Se8 layer was thinned down to the monolayer limit. Interestingly, the AHE signal of those samples was enhanced with the in-plane magnetic fields, suggesting an additional contribution to the AHE signal other than magnetization. This unusual behavior is well reproduced by band structure calculations, where the emergence of the Berry curvature along the spin-degenerate nodal lines in 2D NbSe2 by the in-plane magnetization plays a key role, unveiling a unique interplay between magnetism and Zeeman-type spin-orbit interaction in a non-centrosymmetric 2D quantum material. Van der Waals heterostructures made of 2D materials offer a rich platform for the study of novel proximity effects. Here, by means of Hall effect measurements, the authors show a proximity-induced ferromagnetic/ferrovalley ground state with spontaneous spin-valley polarization in a V5Se8/NbSe2 heterostructure. [ABSTRACT FROM AUTHOR]

This study proposes a new method to introduce the cementation effect into existing elastoplastic constitutive models for soils. The mechanical properties of cement-treated soil are evaluated via element tests and compared with those of naturally deposited clay. The similarities and differences between cement-treated soils and naturally deposited clays are studied, focusing on two states, the undisturbed and remolded states. The effective stress for cement-treated soils incorporating an internal state variable representing the cementation effect is newly defined to describe the mechanical properties of cement-treated soils. Moreover, by applying this extended effective stress to the super-subloading yield surface (SYS) Cam-clay model, which is an elastoplastic model for soils based on the skeleton structure concept, the scope of this constitutive model is extended to include cement-treated soils. The cementation effect introduced by the proposed method allows reproducing the mechanical behavior of the cement-treated soil. Finally, a brittle behavior not described at the element level can be obtained, leading to a soil–water coupled finite deformation analysis incorporating the proposed constitutive model. [ABSTRACT FROM AUTHOR]