Few-molecule reservoir computing experimentally demonstrated with surface enhanced Raman scattering and ion-gating stimulation

Reservoir computing (RC) is a promising solution for achieving low power consumption neuromorphic computing, although the large volume of the physical reservoirs reported to date has been a serious drawback in their practical application. Here, we report the development of a few-molecule RC that employs the molecular vibration dynamics in the para-mercaptobenzoic acid (pMBA) detected by surface enhanced Raman scattering (SERS) with tungsten oxide nanorod/silver nanoparticles (WOx@Ag-NPs). The Raman signals of the pMBA molecules, adsorbed at the SERS active site of WOx@Ag-NPs, were reversibly perturbated by the application of voltage-induced local pH changes in the vicinity of the molecules, and then used to perform RC of pattern recognition and prediction tasks. In spite of the small number of molecules employed, our system achieved good performance, including 95.1% to 97.7% accuracy in various nonlinear waveform transformations and 94.3% accuracy in solving a second-order nonlinear dynamic equation task. Our work provides a new concept of molecular computing with practical computation capabilities.Comment: 22 pages, 4 figure

A high-performance deep reservoir computing experimentally demonstrated with ion-gating reservoirs

While physical reservoir computing (PRC) is a promising way to achieve low power consumption neuromorphic computing, its computational performance is still insufficient at a practical level. One promising approach to improving PRC performance is deep reservoir computing (deep-RC), in which the component reservoirs are multi-layered. However, all of the deep-RC schemes reported so far have been effective only for simulation reservoirs and limited PRCs, and there have been no reports of nanodevice implementations. Here, as the first nanodevice implementation of Deep-RC, we report a demonstration of deep physical reservoir computing using an ion gating reservoir (IGR), which is a small and high-performance physical reservoir. While previously reported Deep-RC scheme did not improve the performance of IGR, our Deep-IGR achieved a normalized mean squared error of 0.0092 on a second-order nonlinear autoregressive moving average task, with is the best performance of any physical reservoir so far reported. More importantly, the device outperformed full simulation reservoir computing. The dramatic performance improvement of the IGR with our deep-RC architecture paves the way for high-performance, large-scale, physical neural network devices.Comment: 21 pages, 6 figure

Evaluation of internal margins for prostate for step and shoot intensity‐modulated radiation therapy and volumetric modulated arc therapy using different margin formulas

[Purpose] This feasibility study evaluated the intra-fractional prostate motion using an ultrasound image-guided system during step and shoot intensity-modulated radiation therapy (SS-IMRT) and volumetric modulated arc therapy (VMAT). Moreover, the internal margins (IMs) using different margin formulas were calculated. [Methods] Fourteen consecutive patients with prostate cancer who underwent SS-IMRT (n = 5) or VMAT (n = 9) between March 2019 and April 2020 were considered. The intra-fractional prostate motion was observed in the superior–inferior (SI), anterior–posterior (AP), and left–right (LR) directions. The displacement of the prostate was defined as the displacement from the initial position at the scanning start time, which was evaluated using the mean ± standard deviation (SD). IMs were calculated using the van Herk and restricted maximum likelihood (REML) formulas for SS-IMRT and VMAT. [Results] For SS-IMRT, the maximum displacements of the prostate motion were 0.17 ± 0.18, 0.56 ± 0.86, and 0.18 ± 0.59 mm in the SI, AP, and LR directions, respectively. For VMAT, the maximum displacements of the prostate motion were 0.19 ± 0.64, 0.22 ± 0.35, and 0.14 ± 0.37 mm in the SI, AP, and LR directions, respectively. The IMs obtained for SS-IMRT and VMAT were within 2.3 mm and 1.2 mm using the van Herk formula and within 1.2 mm and 0.8 mm using the REML formula. [Conclusions] This feasibility study confirmed that intra-fractional prostate motion was observed with SS-IMRT and VMAT using different margin formulas. The IMs should be determined according to each irradiation technique using the REML margin

A characteristic experiment of 4-phase segment type switched reluctance motor

Authors developed a novel segment type switched reluctance motor (SRM) as a rare earth less motor. The torque was increased by 40% and the radial force was decreased by 76% compared with the same size VR type SRM. Increasing the average torque, however, caused increasing torque ripple. In this paper we propose a 4-phase segment type switched reluctance motor and show that the torque ripple can be decreased by controlling the excitation current.15th International Conference on Electrical Machines and Systems, ICEMS 2012; Sapporo; Japan; 21 October 2012 ～ 24 October 201

Copper-catalyzed reaction of aziridine for the synthesis of substituted imidazolidine and imidazolidinone

Herein we report a copper-catalyzed synthesis of imidazolidine by employing the reaction of aziridine with imine. The reaction smoothly provided a diverse range of 2-substituted imidazolidines with high compatibility with various functional groups. Moreover, during our investigation, we discovered that isocyanate also reacted with aziridine to yield substituted imidazolidinones efficiently. The versatility of these reactions was further demonstrated by their application in the synthesis of hybrid molecules derived from two pharmaceutical compounds. This approach opens new possibilities for the discovery of novel classes of bioactive molecules

Pituitary Volume and Socio-Cognitive Functions in Individuals at Risk of Psychosis and Patients With Schizophrenia

Objectives: Increased pituitary volume, which probably reflects hypothalamic-pituitary-adrenal (HPA) hyperactivity, has been reported in patients with schizophrenia and individuals at risk of psychosis. On the basis of potential role of abnormal HPA axis function on cognitive impairments in psychosis, we aimed to examine possible relations between the pituitary volume and socio-cognitive impairments in these subjects.Methods: This magnetic resonance imaging study examined the pituitary gland volume in 38 subjects with at-risk mental state (ARMS) [of whom 4 (10.5%) exhibited the transition to schizophrenia], 63 patients with schizophrenia, and 61 healthy controls. Social and cognitive functions of the ARMS and schizophrenia groups were assessed using the Brief Assessment of Cognition in Schizophrenia (BACS), the Schizophrenia Cognition Rating Scale (SCoRS), and the Social and Occupational Functioning Assessment Scale (SOFAS).Results: Both the ARMS and schizophrenia groups had a significantly larger pituitary volume compared to controls. In the schizophrenia group, the pituitary volume was negatively associated with the BACS working memory score. No association was found between the pituitary volume and clinical variables (medication, symptom severity) in either clinical group.Conclusion: Our findings support the notion of common HPA hyperactivity in the ARMS and schizophrenia groups, but abnormal HPA axis function may contribute differently to cognitive deficits according to the illness stages of schizophrenia

Analysis of T-cell alloantigen response via a direct pathway in kidney transplant recipients with donor-specific antibodies

Donor-specific antibodies (DSAs) are the main cause of graft loss over time. The direct pathway of alloantigen recognition is important in the pathogenesis of acute rejection. Recent studies have suggested that the direct pathway also contributes to the pathogenesis of chronic injury. Nevertheless, there are no reports on T-cell alloantigen response via the direct pathway in kidney recipients with DSAs. We analyzed the T-cell alloantigen response via the direct pathway in kidney recipients with DSAs (DSA+) or without DSAs (DSA−). A mixed lymphocyte reaction assay was implemented to assess the direct pathway response. DSA+ patients showed significantly higher CD8+ and CD4+ T cell responses to donor cells than DSA− patients. Furthermore, proliferating CD4+ T cells showed a marked increase in Th1 and Th17 responses in DSA+ patients than in DSA− patients. In a comparison between anti-donor and third-party responses, the anti-donor CD8+ and CD4+ T cell response was significantly lower than the anti-third-party response. In contrast, the donor-specific hyporesponsiveness was absent in DSA+ patients. Our study demonstrated that DSA+ recipients have a greater potential for developing immune responses against the donor tissues via the direct alloantigen recognition pathway. These data contribute to an understanding of DSAs pathogenicity during kidney transplantation