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The hydrogen exosphere constitutes the uppermost atmospheric layer of the Earth, and its shape may reflect the last stage of the atmospheric escape process. The distribution of hydrogen in the outer exosphere remains unobserved because outer geocoronal emissions are difficult to observe from within the exosphere. In this study, we used the Lyman Alpha Imaging Camera on board the Proximate Object Close Flyby with Optical Navigation spacecraft, located outside the exosphere, to obtain the first image of the entire geocorona that extends to more than 38 Earth radii. The observed emission intensity distribution can be reproduced using our analytical model that has three parameters: exobase temperature, exobase density, and solar radiation pressure, which implies that hot hydrogen production in the magnetized plasmasphere is not the dominant process shaping the outer hydrogen exosphere. However, the role of the magnetic effect in determining the total escape flux cannot be ruled out. In this report, we show the first high‐quality, and wide‐field‐of‐view (FOV) image of Earth's hydrogen corona of 100 Earth radii (RE) obtained by the first interplanetary microspacecraft. Because hydrogen geocorona has not been observed since Apollo 16 in 1972, which observed only up to 10 REof FOV. The field of view of our observation is ~10 times wider than that in past. Furthermore, since the advancement in deep UV detection technology in the last four decades is very large, the improvement in data quality is very large. In fact, our newly obtained data strongly support a different picture for geocorona distribution. More specifically, we found that the observed ecliptic north‐south symmetrical distribution can be reproduced by a simple analytic model and is not consistent with past results. Our result strongly suggests a combination between a compact science instrument and a flexible interplanetary microspacecraft allows us to measure important scientific observables not readily accessible with conventional large‐scale spacecraft missions. The first image of the outer hydrogen geocorona at <16 REshows ecliptic north‐south symmetryWe reproduced the observed spatial distribution using a model with neither a magnetic effect nor a satellite componentSubstantial contribution of the magnetic effect to the escape flux cannot be ruled out

Die Unterscheidung zwischen einer Synovialitis und einem bakteriellen Infekt ist schwierig. Der mikrobiologische Nachweis eines Bakteriums ist nicht immer erfolgreich, und die klinische Relevanz eines wenig virulenten Keims bleibt unklar. Deswegen ist der histopathologische Nachweis einer Entzündungsreaktion wichtig.Von allen Patienten mit klaren Infektionszeichen und chronischer Polyarthritis, die von April bis August 2011 operiert wurden, wurden intraoperativ Proben entnommen. Die histopathologische Diagnose wurde durch konventionelle Enzym- und immunhistochemische Techniken auf der Basis von definierten Kriterien einer bakteriellen Infektion von Weichteilgewebe und Knochen geführt.Es wurden 20 Patienten eingeschlossen, 10 Männer und 10 Frauen, mittleres Alter 61,7 Jahre. Staphylococcus aureuswar der häufigste Keim, in 4 Fällen wurde kein Keim nachgewiesen. Die Korrelation von histologischem und mikrobiologischem Keimnachweis betrug 93,3 %.Bei Patienten mit chronischer Polyarthritis erhöht die Kombination von histologischem und mikrobiologischem Befund die Sicherheit eines Infektionsnachweises oder eines Kontaminationsausschlusses.It can be difficult to distinguish between synovitis due to rheumatism and synovitis due to a bacterial infection. Microbiological detection of bacteria is not always successful and the clinical significance of low virulent bacteria often remains uncertain. Therefore, the histopathological finding of inflammatory reactions is very important.From patients with clinically clear signs of infections and rheumatoid arthritis who underwent surgery between April and August 2011, samples were taken during surgery. Histopathological diagnosis was carried out by conventional enzyme and immunohistochemical techniques based on defined criteria of bacterial infection in tissues, synovial tissue and bone.A total of 20 patients were included, 10 males and 10 females with a mean age of 61.7 years. Staphylococcus aureuswas the most commonly detected bacteria and in 4 cases bacteria could not be demonstrated. The correlation between the histopathological signs of an infection and microbiological detection of bacteria was 93.3 %.In patients with rheumatoid arthritis the combination of histopathology and microbiology significantly increased the safety of detecting an infection or contamination.

A rapid measurement method for aerosol particle size is required to clarify the formation mechanism of freshly-formed radioactive aerosols in accelerator rooms. A graded screen array (GSA) method only requires brief sampling. Therefore, the GSA method is suitable for the measurement of radioactive aerosols in the accelerator rooms. In this work, a conventional GSA was applied to measure the particle size distribution of an aerosol. An influence of the radioactive gas on the GSA measurement was found. The adsorption of radioactive gases resulted in a discrepancy between the results of the GSA method and those of the diffusion battery method. An improved GSA method was developed to measure the radioactive aerosol formed in the accelerator room. The adsorption was measured by the improved GSA, and the influence of the radioactive gas was eliminated. The result of the improved GSA showed fair agreement with that of the diffusion battery system.

Particle size distribution of activity was investigated with an impactor for airborne particles released from a pneumatic irradiation system of a research reactor. Airborne radioactivity released from the pneumatic tube of the reactor was identified as 24Na, 38Cl, and 56Mn and various fission products of which origin was uranium impurity in aluminum used in the part of the pneumatic tube. The AMAD (activity median aerodynamic diameter) of 24Na and 56Mn that were produced through (n,γ) reactions was ca.1 μm, while that of fission products was ca.0.4 μm. It was suggested that radioactive particles of ca.1 μm were due to activation of aluminum dust in the pneumatic tube, and that the particles of ca.0.4 μm were formed by attachment of recoiled fission products to radiation-induced airborne particles.