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A wavelet-based method for compression of three-dimensional simulation data is presented and its software framework is described. It uses wavelet decomposition and subsequent range coding with quantization suitable for floating-point data. The effectiveness of this method is demonstrated by applying it to example numerical tests, ranging from idealized configurations to realistic global-scale simulations. The novelty of this study is in its focus on assessing the impact of compression on post-processing and restart of numerical simulations. [ABSTRACT FROM AUTHOR]

Nirmatrelvir is an orally administered anti -SARS-CoV-2 drug used in combination with ritonavir, the drug-metabolizing cytochrome P450 (CYP) 3A inhibitor, to evade metabolism and extend bioavailability. Meanwhile, the immunosuppressant tacrolimus is a CYP3A4/5 substrate, and CYP3A inhibition results in drug-drug interactions. Herein, we report the case of a coronavirus disease 19 (COVID-19) patient in the maintenance phase post liver transplantation, receiving tacrolimus treatment, with a marked increase of blood tacrolimus levels after the initiation of concomitant nirmatrelvir/ritonavir treatment. A 61-year-old Japanese woman underwent a living donor liver transplant for Caroli disease 25 years ago and received tacrolimus 2 mg/day for immunosuppressive treatment. Three days before the observed high tacrolimus blood concentration, she presented to our emergency department with a fever and was diagnosed with COVID-19. She was prescribed an adjusted dose of nirmatrelvir/ritonavir (150 mg/100 mg, twice daily) for 5 days as a high-risk case with immunosuppressive treatment and reduced renal function (estimated glomerular filtration rate, eGFR: 46.6 mL/min/1.73 m2). At the return visit on day 1, blood tacrolimus level was >60 ng/mL on trough sampling, above the upper limit of measurement, with nausea and vomiting as side effects. Tacrolimus treatment was discontinued on the same day. Drug-drug interactions resulting from CYP3A inhibition by nirmatrelvir/ritonavir were deemed responsible for elevated blood tacrolimus levels. Therefore, in liver transplant recipients, tacrolimus dose reduction or discontinuation is required during COVID-19 treatment with nirmatrelvir/ritonavir. [ABSTRACT FROM AUTHOR]

In this study, we demonstrated the pervasiveness of HIV-associated neurocognitive disorders (HAND) among a selection of Japanese patients as well as evaluated and compared the Mini Mental State Examination (MMSE) and the International HIV Dementia Scale (IHDS) for use as a screening tool among combination anti-retroviral therapy (cART)-naïve and cART experienced patients. The MMSE and the IHDS have both been used as HAND screening tests around the world with variable success. It has been reported the increased usage of cART the utility of these screening tests may have been diminished due to the decreased severity of impairment and the altered pattern of neurocognitive impairments in cART era HAND patients. It is therefore possible the MMSE and the IHDS may still be useful among cART-naïve patients even in the cART era. However, only one study has investigated and compared the screening results of the IHDS among cART-naïve and cART experienced patients. All HIV positive patients who visited, or were admitted, to the Ryukyu University Hospital between January 2009 and March 2014 were evaluated for inclusion. Selected patients (n = 49) had data without omission for all tests. The overall prevalence of HAND in our cohort was 44%. The area under the curve (AUC), for all subjects using the MMSE and the IHDS, were 0.60 and 0.69, respectively. However, the AUC among cART-naïve patients were 0.58 and 0.76 for the MMSE and the IHDS, respectively. Whereas, cART experienced patients had an AUC of 0.60 and 0.61, respectively. Overall, the MMSE demonstrated a poor screening ability for HAND, regardless of cART usage (the cut-off value of 27 had a Youden's J-Index of 0.1, in all groups). Alternatively, the IHDS was moderately useful for HAND screening among cART-naïve patients (the cut-off value of 11 had a Youden's J-Index of 0.4), but performed poorly as a screening test among cART experienced patients (the cut-off value of 11 had a Youden's J-Index of 0.1). [ABSTRACT FROM AUTHOR]

This article presents a case study on the extension of parallel algorithms in tsunami and earthquake-cycle simulators for massively parallel execution on the K computer. We use two target applications: a tsunami-simulation program, “JAGURS,” and an earthquake-cycle program, “RSGDX.” Our optimization strategy for collective communication is to split the Message Passing Interface (MPI) communicator and perform multistage localized communication to minimize the communication frequency, transferred data size, and network congestion. Moreover, in the case of severe load imbalances, we apply cyclic distribution and extend the axes for parallelization. For each application, we conduct a performance evaluation with massively parallel execution on the K computer. It is shown that our optimized code enables JAGURS to attain a 21.8× speedup for collective communication and a 7.9× speedup for the time-step loop on 8748 nodes (69,984 cores). RSGDX attains a 4.25× speedup for collective communication and an 18.7× speedup for the time-step loop on 8192 nodes (65,536 cores). [ABSTRACT FROM AUTHOR]

A numerical sediment transport model (STM) was used to investigate coastal geomorphic changes that resulted from the 2011 Tohoku earthquake tsunami in Rikuzentakata City and Hirota Bay on the southern Sanriku Coast of Japan. The simulation was verified using observed inundation processes and heights, measured topographic changes and sediment deposition. Aerial video footage recorded by the Iwate Prefectural Police was also used. The results show that the numerical model was able to predict the spatial distribution and volume of erosion and deposition in Hirota Bay, as well as sediment transport processes. The effects of sediment transport on tsunami inundation were also investigated. Numerical results revealed that the majority of the sand dunes were eroded by the first wave, especially during the strong return flow of the receding wave. Large flows and sand dune erosions can occur elsewhere if tsunamis inundate a plain with a limited shore-normal width. These events could cause large-scale morphological changes comparable to those that occurred in Rikuzentakata City. [ABSTRACT FROM AUTHOR]

SUMMARY The motor efficiencies of switched reluctance motors (SRMs) are inferior to those of permanent magnet synchronous motors. This paper describes a design procedure for an SRM to obtain a higher motor efficiency. The first step in the design procedure makes clear the principle for improving the motor efficiency. The cross-sectional and axial shapes of the rotor and stator cores are designed by magnetic field analysis with the two-dimensional (2D) and 3D finite element method. A high-efficiency SRM with 12 stator poles and eight rotor poles is designed. The designed SRM was produced experimentally, and was tested to verify its performance. The motor efficiency was improved in comparison to the standard SRM with six stator poles and four rotor poles. [ABSTRACT FROM AUTHOR]

We improved the tsunami simulation code JAGURS, which is a paralleled version of URSGA code for a large-scale, high-speed tsunami prediction in the Nankai trough, Japan. We optimized the loop kernel for velocity update and intergrid communication on a three-dimensional torus network. Linear scaling was achieved up to the full system capability of the K computer (82,944 nodes) in a strong scaling test that used 100 billion finite-difference grid points. The measured performance on the K computer was 1.2 petaflops (11.5% of peak speed). Intergrid communication was optimized for a three-nested-grid model consisting of 0.68 billion grid points. Grid spacing in the area with the finest grid (180 km × 120 km) was about 5 m. We successfully implemented a large-scale tsunami simulation using this model that ran in about 30% of real time. We believe that this is the fastest tsunami prediction achieved to date with such a large-scale model. Our code can provide high-resolution tsunami prediction for broad regions within a reasonable time to assist emergency rescue and relief operations during future devastating tsunamis comparable to the 2004 Sumatra, 2010 Chile, and 2011 Tohoku tsunamis. [ABSTRACT FROM AUTHOR]