Overcoming Failure of Synchronous Motor Driven Compressor Train by Application of Controlled Slip Clutch

Case StudyThis case study describes failure incident of a centrifugal compressor, its root cause investigation, and countermeasure implementation. An integrally geared centrifugal air compressor driven by a synchronous motor failed during its initial startup in a newly constructed petrochemical plant. Failure mechanism was identified as torsional resonance during synchronous motor’s startup with stronger torque amplification than the design intention. As a quick yet very effective solution to this problem, a clutch with controlled slip mechanism was applied. Torsional analysis reflecting the clutch mechanism as well as on-site strain gauge measurement verified its effectiveness. After implementation of this clutch, no malfunction or abnormality has been observed in the compressor train

Magnetic Field-Induced Strain of Metamagnetic Heusler Alloy Ni41Co9Mn31.5Ga18.5

Ni41Co9Mn31.5Ga18.5 is a re-entrant and metamagnetic Heusler alloy. In order to investigate the magnetic functionality of polycrystalline Ni41Co9Mn31.5Ga18.5, magnetic field-induced strain (MFIS) measurements were performed. A 0.12% MFIS was observed at 340 K and 10 T. Strict MFISs between 330 and 370 K were observed. These magneto-structural variances acted in concert with the metamagnetic property observed by the magnetization measurements and magneto-caloric property observed by the caloric measurements in applied magnetic fields. The MFISs were proportional to the fourth power of the magnetization, and this result is in agreement with Takahashi’s spin fluctuation theory of itinerant electron magnetism. The investigation of time response of the MFIS was performed by means of water-cooled electric magnet, zero magnetic field to 1.66 T in 8.0 s at 354 K. A 2.2×10−4 MFIS was observed, which was 80% of the MFIS in a 60-s mode. This indicates that a high-speed transition has occurred on applying magnetic fields

Human intestinal spirochetosis accompanied by human immunodeficiency virus infection:a case report

We present a middle-aged, heterosexual Japanese man with mixed infections including human intestinal spirochetosis, which led us to the detection of human immunodeficiency virus (HIV) infection. The patient had syphilis without related physical or neurological findings. An examination for the serum antibody for HIV performed 9 years previously was negative. In a complete medical checkup at the present time, human intestinal spirochetosis and unspecified entamebic cysts were suggested by histological examination of colonic biopsy material and parasitic examination of the intestinal fluid, respectively. Moreover, a serological test for the antibody for HIV was positive. In specimens obtained by colonoscopy, Brachyspira aalborgi was diagnosed by ultrastructural study and the polymerase chain reaction method for bacterial 16S ribosomal deoxyribonucleic acid. Although HIV infection remains at low prevalence in Japan, we recommend examination for HIV infection in patients with human intestinal spirochetosis, especially when other co-infections are apparent.</p

The MAXI Mission on the ISS: Science and Instruments for Monitoring All Sky X-Ray Images

The MAXI (Monitor of All-sky X-ray Image) mission is the first astronomical payload to be installed on the Japanese Experiment Module-Exposed Facility (JEM-EF) on the ISS. It is scheduled for launch in the middle of 2009 to monitor all-sky X-ray objects on every ISS orbit. MAXI will be more powerful than any previous X-ray All Sky Monitor (ASM) payloads, being able to monitor hundreds of AGN. MAXI will provide all sky images of X-ray sources of about 20 mCrab in the energy band of 2-30 keV from observation on one ISS orbit (90 min), about 4.5 mCrab for one day, and about 1 mCrab for one month. A final detectability of MAXI could be 0.2 mCrab for 2 year observations.Comment: 12 pages, 11 figures, accepted for publication in Publications of the Astronomical Society of Japa

A signature of aged biogenic compounds detected from airborne VOC measurements in the high arctic atmosphere in March/April 2018

During the PAMARCMiP 2018 campaign (March and April 2018) a proton-transfer-reaction mass spectrometer (PTR-MS) was deployed onboard the POLAR 5 research aircraft and sampled the high Arctic atmosphere under Arctic haze conditions. More than 100 compounds exhibited levels above 1 pmol/mol in at least 25% of the measurements. We used acetone mixing ratios, ozone concentrations, and back trajectories to identify periods with and without long-range transport from continental sources. During two flights, surface ozone depletion events (ODE) were observed that coincided with enhanced levels of acetone, and methylethylketone, and ice nucleating particles (INP).Air masses with continental influence contained elevated levels of compounds associated with aged biogenic emissions and anthropogenic pollution (e.g., methanol, peroxyacetylnitrate (PAN), acetone, acetic acid, meth-ylethylketone (MEK), proprionic acid, and pentanone). Almost half of all positively detected compounds (>100) in the high Arctic atmosphere can be associated with terpene oxidation products, likely produced from mono-terpenes and sesquiterpenes emitted from boreal forests. We speculate that the transport of biogenic terpene emissions may constitute an important control of the High Arctic aerosol burden. The sum concentration of the detected aerosol forming vapours is-12 pmol/mol, which is of the same order than measured dimethylsulfide (DMS) mixing ratios and their mass density corresponds to approximately one fifth of the measured non-black -carbon particles

Concentrations and size distributions of black carbon in the surface snow of Eastern Antarctica in 2011

The Tenth Symposium on Polar Science/Ordinary sessions: [OM] Polar Meteorology and Glaciology, Thu. 5 Dec. / 2F Auditorium , National Institute of Polar Researc

Multicenter, single-blind, randomized controlled study of the efficacy and safety of favipiravir and nafamostat mesilate in patients with COVID-19 pneumonia

Objectives: To evaluate the efficacy and safety of nafamostat combined with favipiravir for the treatment of COVID-19. Methods: We conducted a multicenter, randomized, single-blind, placebo-controlled, parallel assignment study in hospitalized patients with mild-to-moderate COVID-19 pneumonia. Patients were randomly assigned to receive favipiravir alone (n = 24) or nafamostat with favipiravir (n = 21). The outcomes included changes in the World Health Organization clinical progression scale score, time to improvement in body temperature, and improvement in oxygen saturation (SpO2). Results: There was no significant difference in the changes in the clinical progression scale between nafamostat with favipiravir and favipiravir alone groups (median, -0.444 vs -0.150, respectively; least-squares mean difference, -0.294; P = 0.364). The time to improvement in body temperature was significantly shorter in the combination group (5.0 days; 95% confidence interval, 4.0-7.0) than in the favipiravir group (9.0 days; 95% confidence interval, 7.0-18.0; P =0.009). The changes in SpO2 were greater in the combination group than in the favipiravir group (0.526% vs -1.304%, respectively; least-squares mean difference, 1.831; P = 0.022). No serious adverse events or deaths were reported, but phlebitis occurred in 57.1% of the patients in the combination group. Conclusion: Although our study showed no differences in clinical progression, earlier defervescence, and recovery of SpO2 were observed in the combination group

Infectious virus shedding duration reflects secretory IgA antibody response latency after SARS-CoV-2 infection

新型コロナウイルス排出と粘膜抗体の関係を解明 --呼吸器ウイルスのヒト間伝播を制御・予防する第一歩--. 京都大学プレスリリース. 2023-12-25.Articles: Infectious virus shedding duration reflects secretory IgA antibody response latency after SARS-CoV-2 infection. 京都大学プレスリリース. 2023-12-25.Infectious virus shedding from individuals infected with severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) is used to estimate human-to-human transmission risk. Control of SARS-CoV-2 transmission requires identifying the immune correlates that protect infectious virus shedding. Mucosal immunity prevents infection by SARS-CoV-2, which replicates in the respiratory epithelium and spreads rapidly to other hosts. However, whether mucosal immunity prevents the shedding of the infectious virus in SARS-CoV-2-infected individuals is unknown. We examined the relationship between viral RNA shedding dynamics, duration of infectious virus shedding, and mucosal antibody responses during SARS-CoV-2 infection. Anti-spike secretory IgA antibodies (S-IgA) reduced viral RNA load and infectivity more than anti-spike IgG/IgA antibodies in infected nasopharyngeal samples. Compared with the IgG/IgA response, the anti-spike S-IgA post-infection responses affected the viral RNA shedding dynamics and predicted the duration of infectious virus shedding regardless of the immune history. These findings highlight the importance of anti-spike S-IgA responses in individuals infected with SARS-CoV-2 for preventing infectious virus shedding and SARS-CoV-2 transmission. Developing medical countermeasures to shorten S-IgA response time may help control human-to-human transmission of SARS-CoV-2 infection and prevent future respiratory virus pandemics