Antiferromagnetic Coupling of Pr0.9RE0.1Ni (RE = Tb, Dy, Ho) Single Crystals

Magnetization and specific heat measurements were carried out on Pr0.9RE0.1Ni (RE = Tb,Dy, and Ho) single crystals. Spin rearrangements were observed along the c-axis ofsingle crystals with relatively small critical fields, Bc = 6.8, 4.0 and 2.6 T for RE = Tb,Dy and Ho, respectively. The magnetic phase transition temperatures, TM, were extracted from the specific heat data: TM = 22.7, 19.6 and 18.3 K with RE = Tb, Dy and Ho, respectively. The observed Bc values were used to estimate the heterogeneous (Pr-RE) exchange strength, and then calculate expected TM values, which were found to be close to the experimental ones. The present results of Bc and TM, together with the previous ones of Pr0.9Gd0.1Ni, were found to be consistent with the de Gennes rule

Reentrant spin-glass behavior induced by the frustration of Fe-Fe interactions in Laves phase Nb1-xHfxFe2 alloys

We carried out magnetization and specific-heat measurements of metallic compoundsNb1-xHfxFe2 (x = 0 and 0.65), which exhibit reentrant spin-glass freezing. The frequencydependence of ac susceptibility and the bifurcation between zero-field-cooled and field-cooledmagnetization curves suggest the complex coexistence of magnetic phases at low temperatures. A long-time relaxation of magnetization is possibly due to the cluster-type and traditional reentrant spin-glass transition, which may be induced by the frustration of long-range Fe-Fe interactions. We did not observe any discontinuity indicating long-range magnetic phase transition in the data of specific heat vs temperature, but a broad hump characteristic of spin-glass freezing. The difference between the behaviors of two samples proves the existence of two types of reentrant spin-glass in alloys. The moment arrangements are briefly discussed.PACS number(s): 75.50.Lk; 75.30.Kz; 75.50.B

Web-based environment for user generation of spoken dialog for virtual assistants

In this paper, a web-based spoken dialog generation environment which enables users to edit dialogs with a video virtual assistant is developed and to also select the 3D motions and tone of voice for the assistant. In our proposed system, “anyone” can “easily” post/edit contents of the dialog for the dialog system. The dialog type corresponding to the system is limited to the question-and-answer type dialog, in order to avoid editing conflicts caused by editing by multiple users. The spoken dialog sharing service and FST generator generates spoken dialog content for the MMDAgent spoken dialog system toolkit, which includes a speech recognizer, a dialog control unit, a speech synthesizer, and a virtual agent. For dialog content creation, question-and-answer dialogs posted by users and FST templates are used. The proposed system was operated for more than a year in a student lounge at the Nagoya Institute of Technology, where users added more than 500 dialogs during the experiment. Images were also registered to 65% of the postings. The most posted category is related to “animation, video games, manga.” The system was subjected to open examination by tourist information staff who had no prior experience with spoken dialog systems. Based on their impressions of tourist use of the dialog system, they shortened the length of some of the system’s responses and added pauses to the longer responses to make them easier to understand

MMDAE : Dialog scenario editor for MMDAgent on the web browser

We have developed MMDAgent (a fully open-source toolkit for voice interaction systems), which runs on a variety of platforms such as personal computers and smartphones. From this, the editing environment of the dialog scenario also needs to be operated on various platforms. So, we develop a scenario editor that is implemented on a Web browser. The purpose of this paper also includes making it easy to edit the scenario. Experiments were conducted for subjects using the proposed scenario editor. It was found that our proposed system provides better readability of a scenario and allows easier editing

Ultralow radiant exposure of a short-pulsed laser to disrupt melanosomes with localized thermal damage through a turbid medium

Shimojo Y., Nishimura T., Tsuruta D., et al. Ultralow radiant exposure of a short-pulsed laser to disrupt melanosomes with localized thermal damage through a turbid medium. Scientific Reports 14, 20112 (2024); https://doi.org/10.1038/s41598-024-70807-7.Short-pulsed lasers can treat dermal pigmented lesions through selective photothermolysis. The irradiated light experiences multiple scattering by the skin and is absorbed by abnormal melanosomes as well as by normal blood vessels above the target. Because the fluence is extremely high, the absorbed light can cause thermal damage to the adjacent tissue components, leading to complications. To minimize radiant exposure and reduce the risk of burns, a model of the melanosome-disruption threshold fluence (MDTF) has been developed that accounts for the light-propagation efficiency in the skin. However, the light-propagation efficiency is attenuated because of multiple scattering, which limits the extent to which the radiant exposure required for treatment can be reduced. Here, this study demonstrates the principle of melanosome disruption with localized thermal damage through a turbid medium by ultralow radiant exposure of a short-pulsed laser. The MDTF model was combined with a wavefront-shaping technique to design an irradiation condition that can increase the light-propagation efficiency to the target. Under this irradiation condition, melanosomes were disrupted at a radiant exposure 25 times lower than the minimal value used in conventional laser treatments. Furthermore, almost no thermal damage to the skin was confirmed through a numerical simulation. These experimental and numerical results show the potential for noninvasive melanosome disruption and may lead to the improvement of the safety of short-pulsed laser treatment

Diagnosis of the repetitive brain concussion

In this paper the effectiveness of the support system which predicts the risk of the repetitive brain concussion is studied biomechanically. In the risk prediction system, the accident that caused the concussion is reconstructed by analyzing the game video via multibody dynamics and the resulting brain injury is calculated in detail by the finite element method. In order to calculate the aggravation of the brain injury by the repeated brain concussion, the following two methods are examined. In the first method, the material properties of the part of the brain damaged by the1st impact are changed in the simulation of the 2nd impact. In the second method, each brain damage caused by the repeated impacts is accumulated. The system was applied to the real-life accidents that occurred during Judo and American football games. As a result of the simulations, the aggravation of the brain damage due to repetitive concussion was determined numerically in terms of the maximum strain of the brain and the brain damage rate of the whole brain. The biomechanical process of the collision accidents and the resulting brain damage were reconstructed based on the video and the results are effective to prevent the future repeated concussion accidents