Modeling of geocoronal solar wind charge exchange events detected with Suzaku

A model of geocoronal solar wind charge exchange (SWCX) emission was built and compared to five Suzaku detections of bright geocoronal SWCX events. An exospheric neutral hydrogen distribution model, charge exchange cross sections, solar wind ion data taken with the ACE and WIND satellites, and magnetic field models of the Earth's magnetosphere are all combined in order to predict time-variable geocoronal SWCX emission depending on line-of-sight directions of the Suzaku satellite. The modeled average intensities of O VII emission lines were consistent with the observed ones within a factor of three in four out of the five cases except for an event in which a line-of-sight direction was toward the night side of the high-latitude magnetosheath and a major geomagnetic storm was observed. Those of O VIII emission lines were underestimated by a factor of three or more in all the five cases. On the other hand, the modeled O VII and O VIII light curves reproduced the observed ones after being scaled by ratios between the observed and modeled average intensities. In particular, short-term variations due to line-of-sight directions traversing cusp regions during an orbital motion of the Suzaku satellite were reproduced. These results are discussed in the context of model uncertainties.Comment: 47 pages, 23 figures, accepted for publication in PAS

Distance measurements between 5 nanometer diamonds – single particle magnetic resonance or optical super-resolution imaging?

5 nanometer sized detonation nanodiamonds (DNDs) are studied as potential single-particle labels for distance measurements in biomolecules

Pneumonia Caused by Severe Acute Respiratory Syndrome Coronavirus 2 and Influenza Virus: A Multicenter Comparative Study

Background: Detailed differences in clinical information between severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia (CP), which is the main phenotype of SARS-CoV-2 disease, and influenza pneumonia (IP) are still unclear. Methods: A prospective, multicenter cohort study was conducted by including patients with CP who were hospitalized between January and June 2020 and a retrospective cohort of patients with IP hospitalized from 2009 to 2020. We compared the clinical presentations and studied the prognostic factors of CP and IP. Results: Compared with the IP group (n = 66), in the multivariate analysis, the CP group (n = 362) had a lower percentage of patients with underlying asthma or chronic obstructive pulmonary disease (P < .01), lower neutrophil-to-lymphocyte ratio (P < .01), lower systolic blood pressure (P < .01), higher diastolic blood pressure (P < .01), lower aspartate aminotransferase level (P < .05), higher serum sodium level (P < .05), and more frequent multilobar infiltrates (P < .05). The diagnostic scoring system based on these findings showed excellent differentiation between CP and IP (area under the receiver operating characteristic curve, 0.889). Moreover, the prognostic predictors were different between CP and IP. Conclusions: Comprehensive differences between CP and IP were revealed, highlighting the need for early differentiation between these 2 pneumonias in clinical settings

Urine volume to hydration volume ratio is associated with pharmacokinetics of high-dose methotrexate in patients with primary central nervous system lymphoma.

High-dose methotrexate (HD-MTX)-based chemotherapy is the first-line treatment for primary central nervous system lymphoma (PCNSL), but is associated with severe adverse effects, including myelosuppression and renal impairment. MTX is primarily excreted by the kidneys. Renal function calculated using serum creatinine (Scr) derived from muscle may be overestimated in elderly PCNSL patients. Therefore, we aimed to construct a population pharmacokinetic model in PCNSL patients and explore the factors associated with MTX clearance. Sixteen PCNSL patients (median age, 66 years) treated with HD-MTX were included, and serum MTX concentrations were measured at 193 points in 49 courses. A population pharmacokinetic analysis was performed using NONMEM. A Monte Carlo simulation was conducted, in which serum MTX concentrations were stratified into three groups of creatine clearance (Ccr) (50, 75, and 100 ml/min) with three groups of the urine volume to hydration volume (UV/HV) ratio (2). The final model was constructed as follows: MTX clearance = 4.90·(Ccr/94.5)0.456·(UV/HV)0.458. In the Monte Carlo simulation, serum MTX concentrations were below the standard values (10, 1, and 0.1 µM at 24, 48, and 72 h, respectively, after the start of the MTX administration) in most patients with UV/HV >2, even with Ccr of 50 ml/min. Conversely, half of the patients with UV/HV <1 and Ccr of 50 ml/min failed to achieve the standard values. The present results demonstrated that the UV/HV ratio was useful for describing the pharmacokinetics of MTX in PCNSL patients

Pharmacokinetics of Intravitreal Vancomycin and Ceftazidime in Silicone Oil-Filled Macaque Eyes.

Purpose:This study evaluated the pharmacokinetics of intravitreal vancomycin and ceftazidime in the aqueous humor of macaque eyes filled with silicone oil in the vitreous cavity.Methods:Intravitreal vancomycin (1 mg/0.1 mL) and ceftazidime (2 mg/0.1 mL) were injected into four normal macaque eyes, four vitrectomized aphakic macaque eyes, and four previously vitrectomized aphakic macaque eyes filled with silicone oil (silicone oil-filled eyes). Aqueous humor samples (0.1 mL) were obtained just before injection and at 2 and 5 hours and 1, 2, 3, 5, 7, and 10 days after injection. In each group, corneal endothelial cell density (ECD) measurements and electroretinogram (ERG) recordings were obtained before injection and after 1 month.Results:The half-lives of vancomycin in the aqueous humor of normal, vitrectomized, and silicone oil-filled eyes were 29.4, 21.1, and 6.8 hours, respectively, and those of ceftazidime were 20.4, 5.2, and 3.1 hours, respectively. The maximum vancomycin aqueous humor concentrations of normal, vitrectomized, and silicone oil-filled eyes were 151.4, 205.6, and 543.5 µg/mL, respectively, and the maximum ceftazidime aqueous humor concentrations are 64.6, 260.0, and 1176.3 µg/mL, respectively. There was no change in ECD, and ERG was not declined after intravitreal injection in all groups.Conclusions:The half-lives of vancomycin and ceftazidime in the aqueous humor were shorter in silicone oil-filled eyes than in normal and vitrectomized eyes. High antibiotic concentrations in silicone oil-filled eyes seemed to be well tolerated.Translational Relevance:This study aids in estimating how often an antibiotic should be intravitreally injected for endophthalmitis of silicone oil-filled eyes

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements