Development of Gas Multiplier Counters (GMCs) Onboard the 6U CubeSat X-Ray Observatory NinjaSat

We report the development of Gas Multiplier Counters (GMCs) onboard the 6U CubeSat X-ray observatory NinjaSat, scheduled to be launched in October 2023. GMC is a 1U-size non-imaging gas X-ray detector sensitive to 2–50 keV X-rays, and two identical GMCs are mounted on NinjaSat. GMC consists of a gas cell filled with a xenon/argon/dimethyl ether (75%/24%/1%) gas mixture with a pressure of 1.2 atm at 0◦C, a high voltage supply and analog signal processing board, a digital signal processing board, an X-ray collimator of a 2.1◦ field of view, and an iron-55 calibration source. The most significant feature of the GMC is its large effective area of 32 cm2 at 6 keV, which is more than two orders of magnitude larger than the X-ray detectors onboard previously launched CubeSats. We have achieved this at a low cost and in a short development time by employing a gas detector that can easily increase its effective area and using a space-proven gas electron multiplier. GMC was characterized with X-rays from an X-ray generator in a laboratory and monochromatic X-rays on the BL-14A beamline at the KEK synchrotron radiation facility. In this paper, we present the design of GMC and the preliminary results of the detector calibration

NinjaSat: 6U CubeSat Observatory for Bright X-Ray Sources

NinjaSat is a 6U CubeSat observatory designed for long-term monitoring of bright X-ray sources, such as binary systems between normal stars and black holes or neutron stars. NinjaSat is the first Japanese CubeSat dedicated to astronomical observation, and it is also a mission to demonstrate that even a small satellite, which can be developed quickly and inexpensively, unlike large satellites, can perform excellent scientific observations. NinjaSat realizes the world’s highest X-ray sensitivity in CubeSat missions by using gas X-ray detectors filling the entire space allocated for science payloads. The fabrication of the flight model payloads began in 2021, and testing at the payload component level was completed in August 2022; as of April 2023, the payloads were integrated into the Nano Avionics 6U bus (M6P) in Lithuania. After four months of testing, the payload will be stored in the Exolaunch deployer in August and launched by the SpaceX Transporter-9 mission in October 2023. This paper will describe the scientific objectives, satellite structure, payloads, and operations of NinjaSat

Development of Radiation Belt Monitors for the 6U CubeSat X-Ray Observatory NinjaSat

NinjaSat is a 6U CubeSat-sized X-ray observatory to be launched into the low Earth orbit at an altitude of 550 km, and is scheduled for launch this October. NinjaSat is equipped with two 1U-sized gas X-ray detectors (GMC) and is expected to operate mainly for astronomical observations of bright X-ray objects in the sky, such as neutron stars and black holes. Since high voltages are applied to the gas cells of GMC, two radiation belt monitors (RBM) will also be installed to protect GMC from electrical discharges potentially caused by excessively high rate of charged particles. NinjaSat RBM will play a fail-safe function in the voltage suppression operation of GMC in the auroral zone and South Atlantic Anomaly, and also protect GMC from charged particles such as protons and electrons that arrive unexpectedly due to solar flares or other low-Earth orbit radiation events. RBM uses a 9 mm x 9 mm Si-PIN photodiode as a charged particle sensor. By taking advantage of the difference in sensor response to protons and electrons, the sensor is designed to simultaneously count charged particle rates at multiple energy thresholds so that GMC protection function will operate even if either the proton or electron rate increases. RBM can count up to about 10 kcps with almost no loss of counts, and proton beam tests have confirmed that the response performance is sufficient to protect GMC against excessively high charged particle rates above 10 Mcps without choking the circuitry. The flight models of the RBM have passed the thermal vacuum and vibration tests last year. The developed RBM occupies only about 6% of the 1U CubeSat size in volume and weighs only 70g. In addition, since the RBM uses inexpensive, commercially available sensors, it could be installed on small satellites other than NinjaSat with relatively small development resources

Development of Kupffer cell targeting type-I interferon for the treatment of hepatitis via inducing anti-inflammatory and immunomodulatory actions

Because of its multifaceted anti-inflammatory and immunomodulatory effects, delivering type-I interferon to Kupffer cells has the potential to function as a novel type of therapy for the treatment of various types of hepatitis. We report herein on the preparation of a Kupffer cell targeting type-I interferon, an albumin-IFNα2b fusion protein that contains highly mannosylated N-linked oligosaccharide chains, Man-HSA(D494N)-IFNα2b, attached by combining albumin fusion technology and site-directed mutagenesis. The presence of this unique oligosaccharide permits the protein to be efficiently, rapidly and preferentially distributed to Kupffer cells. Likewise IFNα2b, Man-HSA(D494N)-IFNα2b caused a significant induction in the mRNA levels of IL-10, IL-1Ra, PD-L1 in RAW264.7 cells and mouse isolated Kupffer cells, and these inductions were largely inhibited by blocking the interferon receptor. These data indicate that Man-HSA(D494N)-IFNα2b retained the biological activities of type-I interferon. Man-HSA(D494N)-IFNα2b significantly inhibited liver injury in Concanavalin A (Con-A)-induced hepatitis model mice, and consequently improved their survival rate. Moreover, the post-administration of Man-HSA(D494N)-IFNα2b at 2 h after the Con-A challenge also exerted hepato-protective effects. In conclusion, this proof-of-concept study demonstrates the therapeutic effectiveness and utility of Kupffer cell targeting type-I interferon against hepatitis via its anti-inflammatory and immunomodulatory actions

Characterization of Ion Cyclotron Wall Conditioning Using Material Probes in LHD

The ion cyclotron wall conditioning (ICWC) is one of the conditioning methods to reduce impurities and to remove tritium from the plasma facing components. Among the advantages of ICWC are the possible operation under strong magnetic field for fully torus area based on the charge exchange damage observed in thin SS samples arranged on a hexahxedron block holder with three different facings, the areas influenced by ICWC is estimated. On the plasma facing area of the material holder, high density of helium bubbles is observed by transmission electron microscope (TEM). But the other areas show no observable damage. The fact that the bubble were observed only in a sample facing the plasma implies that the effective particles, most probably charge exchange neutrals come to the wall straightly Thus, cleaning of the surfaces un-exposed to plasma directly and those in shadow area is difficult by ICWC

Allergic reactions to propofol in adult patients with egg or soybean allergy: a retrospective cohort study from a large database of a single institute

Abstract Background In recent years, many reports have indicated that propofol is safe to administer to patients with egg/soybean allergy in Western countries. Egg allergy is more frequent in Asia, but there are limited reports regarding allergic reactions to propofol use among adults. This study aimed to determine whether propofol causes allergic reactions in patients with egg/soybean allergy. Methods Adult patients who underwent surgery involving anesthesiologists from 2018 to 2021 were included. In all patients, we reviewed food allergy information in their electronic medical record and extracted anesthetics. Patients with egg/soybean allergy were subdivided into two groups on the basis of intraoperative use of propofol. We evaluated each group for allergic reactions within 24 h after the induction of anesthesia. The primary outcome was a relative risk of allergic reactions after propofol use for patients with egg/soybean allergy. Results In total, 22,111 patients with 28,710 anesthesia records were identified. Among patients with egg/soybean allergy, 173 (0.8%) patients and 237 (0.8%) anesthesia records were included in the study. Among the records of egg-/soybean-allergic patients, 151 were administered propofol, and 86 were not. The relative risk of allergic reactions after propofol use for patients with egg/soybean allergy was 1.14 (95% confidence interval, 0.10–12.4; p = 0.74). Conclusion The use of propofol in patients with egg/soybean allergy does not significantly increase the relative risk of allergic reactions. Therefore, anesthesiologists can appropriately determine the indication for propofol, even in patients with egg/soybean allergy. Trial registration UMIN-CTN, UMIN000049321 registered 26 October 2022 — retrospectively registered, https://center6.umin.ac.jp/cgi-open-bin/ctr/ctr_view.cgi?recptno=R00005616

Sildenafil ameliorates right ventricular early molecular derangement during left ventricular pressure overload.

Right ventricular (RV) dysfunction following left ventricular (LV) failure is associated with poor prognosis. RV remodeling is thought initiated by the increase in the afterload of RV due to secondary pulmonary hypertension (PH) to impaired LV function; however, RV molecular changes might occur in earlier stages of the disease. cGMP (cyclic guanosine monophosphate)-phosphodiesterase 5 (PDE5) inhibitors, widely used to treat PH through their pulmonary vasorelaxation properties, have shown direct cardiac benefits, but their impacts on the RV in LV diseases are not fully determined. Here we show that RV molecular alterations occur early in the absence of RV hemodynamic changes during LV pressure-overload and are ameliorated by PDE5 inhibition. Two-day moderate LV pressure-overload (transverse aortic constriction) neither altered RV pressure/ function nor RV weight in mice, while it induced only mild LV hypertrophy. Importantly, pathological molecular features were already induced in the RV free wall myocardium, including up-regulation of gene markers for hypertrophy and inflammation, and activation of extracellular signal-regulated kinase (ERK) and calcineurin. Concomitant PDE5 inhibition (sildenafil) prevented induction of such pathological genes and activation of ERK and calcineurin in the RV as well as in the LV. Importantly, dexamethasone also prevented these RV molecular changes, similarly to sildenafil treatment. These results suggest the contributory role of inflammation to the early pathological interventricular interaction between RV and LV. The current study provides the first evidence for the novel early molecular cross-talk between RV and LV, preceding RV hemodynamic changes in LV disease, and supports the therapeutic strategy of enhancing cGMP signaling pathway to treat heart diseases

Invasive hemodynamic studies revealed two-day transverse aortic constriction affect neither right ventricular pressure nor function.

<p>(A) Peak systolic left ventricular pressure (LVP sys) and mean right ventricular pressure (RVP mean). Transverse aortic constriction (TAC) for two days increased systolic LV pressure, but had no effects on RV pressure. Sildenafil did not affect either pressure. (B) Peak rate of ventricular pressure rise (dP/dt_max), peak rate of ventricular decline (dP/dt_min), and relaxation time constant (tau). LV tau was prolonged by two-day TAC, which was normalized by sildenafil. Results are expressed as mean ± s.e.m. (n = 3). TAC 2d Veh, TAC for 2 days with vehicle treatment; TAC 2d Sil, TAC for 2days with sildenafil treatment. n.s., not significant by one-way analysis of variance; *, p < 0.05 versus sham group; §, p = 0.05 versus sham group; ‡, p = 0.07 versus TAC 2d Veh group.</p

Pathological gene induction in RV as well as LV were ameliorated by sildenafil.

<p>(A) Expression of fetal genes as markers of cardiac hypertrophy, encoding for BNP and B-MHC, normalized to GAPDH. Transverse aortic constriction (TAC) for two days induced marked increase in BNP mRNA levels in the RV myocardium as well as in the LV myocardium, which was prevented by sildenafil. Expression of B-MHC was increased by two-day TAC in LV, but was not affected by sildenafil. (B) Expression of inflammatory cytokines, IL1b and IL6, normalized to GAPDH. IL1b and IL6 was up-regulated by TAC in both ventricles. Sildenafil inhibited both in LV, and also attenuated both in RV. (C) Expression of genes for enzymes inducing oxidative stress, NOX2 and NOX4, normalized to GAPDH. Expression of NOX2 was increased by TAC in both ventricles, and suppressed by sildenafil in LV. TAC and sildenafil had little influence on NOX4 expression. Results are expressed as mean ± s.e.m. (n = 5). TAC 2d Veh, TAC for 2 days with vehicle treatment; TAC 2d Sil, TAC for 2days with sildenafil treatment. n.s., not significant by one-way analysis of variance; *, p<0.05 versus sham group; ✝, p<0.05 versus the TAC 2d Veh group.</p

Macrophage infiltration into myocardium was induced also in the RV, which was suppressed by sildenafil.

<p>(A-C) Myocardium stained for F4/80⁺ cells in the RV and the LV of the Sham mouse (A), the TAC-2d-Veh mouse (B), and the TAC-2d-Sil mouse (C). Arrows: F4/80⁺ cells. Magnification x200. (D) The number of F4/80⁺ cells per high-power field. Transverse aortic constriction for two days induced F4/80⁺ macrophage infiltration into myocardium not only in the LV but also in the RV, which was suppressed by sildenafil. Results are expressed as mean ± s.e.m. (n = 10). TAC 2d Veh, TAC for 2 days with vehicle treatment; TAC 2d Sil, TAC for 2days with sildenafil treatment. *, p<0.05 versus sham group; ✝, p<0.05 versus the TAC 2d Veh group.</p