Mineralogy and crystallography of some Itokawa particles returned by the Hayabusa asteroidal sample return mission

We studied seven Itokawa particles provided by the Japan Aerospace Exploration Agency (JAXA) as first International Announcement of Opportunity (AO) study mainly using electron and synchrotron radiation X-ray beam techniques. All the analyzed particles were collected from the first-touchdown site and composed of olivine and plagioclase with traces of Ca phosphate and chromite, and do not contain pyroxenes. Optical microscopy of these particles shows minor undulatory extinction of olivine and plagioclase, suggesting minor shock metamorphism (shock stage: S2). The electron microprobe analysis shows that olivine is Fo(70-73) and plagioclase is An(13-10)Or(5-7). The synchrotron radiation X-ray diffraction (SR-XRD) analysis of olivine crystals gives cell dimensions of a = 4.708 to 4.779 angstrom, b = 10.271 to 10.289 angstrom, c = 6.017 to 6.024 angstrom, corresponding to the Fo content of Fo(similar to 70) by Vegard's law. This composition matches the result obtained by the electron microprobe analysis. The olivine compositions of the analyzed particles are consistent with those of LL chondrites. The cell dimensions of two plagioclase crystals (a = 8.180 to 8.194 angstrom, b = 12.53 to 12.893 angstrom, c = 7.125 to 7.23 angstrom, a = 92.6 degrees to 93.00 degrees, beta = 116.36 degrees to 116.75 degrees, gamma = 90.03 degrees to 90.17 degrees) indicate that their equilibration temperatures are 800 degrees C +/- 10 degrees C. This temperature is near the peak metamorphic temperature recorded by equilibrated ordinary chondrites. The size of plagioclase crystals and the homogeneity of olivine compositions indicate that their petrologic type is >= 5. We also analyzed plagioclase by SR iron X-ray absorption near-edge structure (SR-XANES) and found that its Fe3+/(Fe2+ + Fe3+) ratio is approximately 0.5. Such high Fe3+ abundance indicates the formation under a relatively oxidizing environment. Thus, all these analyses have reconfirmed that the Itokawa particles returned by the Hayabusa spacecraft are very weakly shocked equilibrated LL chondrites, which matches the results of the preliminary examination team

Real-Time Prediction of Growth Characteristics for Individual Fruits Using Deep Learning

Understanding the growth status of fruits can enable precise growth management and improve the product quality. Previous studies have rarely used deep learning to observe changes over time, and manual annotation is required to detect hidden regions of fruit. Thus, additional research is required for automatic annotation and tracking fruit changes over time. We propose a system to record the growth characteristics of individual apples in real time using Mask R-CNN. To accurately detect fruit regions hidden behind leaves and other fruits, we developed a region detection model by automatically generating 3000 composite orchard images using cropped images of leaves and fruits. The effectiveness of the proposed method was verified on a total of 1417 orchard images obtained from the monitoring system, tracking the size of fruits in the images. The mean absolute percentage error between the true value manually annotated from the images and detection value provided by the proposed method was less than 0.079, suggesting that the proposed method could extract fruit sizes in real time with high accuracy. Moreover, each prediction could capture a relative growth curve that closely matched the actual curve after approximately 150 elapsed days, even if a target fruit was partially hidden

Mineralogy and crystallography of some Itokawa particles returned by the Hayabusa asteroidal sample return mission

We studied seven Itokawa particles provided by the Japan Aerospace Exploration Agency (JAXA) as first International Announcement of Opportunity (AO) study mainly using electron and synchrotron radiation X-ray beam techniques. All the analyzed particles were collected from the first-touchdown site and composed of olivine and plagioclase with traces of Ca phosphate and chromite, and do not contain pyroxenes. Optical microscopy of these particles shows minor undulatory extinction of olivine and plagioclase, suggesting minor shock metamorphism (shock stage: S2). The electron microprobe analysis shows that olivine is Fo(70-73) and plagioclase is An(13-10)Or(5-7). The synchrotron radiation X-ray diffraction (SR-XRD) analysis of olivine crystals gives cell dimensions of a = 4.708 to 4.779 angstrom, b = 10.271 to 10.289 angstrom, c = 6.017 to 6.024 angstrom, corresponding to the Fo content of Fo(similar to 70) by Vegard's law. This composition matches the result obtained by the electron microprobe analysis. The olivine compositions of the analyzed particles are consistent with those of LL chondrites. The cell dimensions of two plagioclase crystals (a = 8.180 to 8.194 angstrom, b = 12.53 to 12.893 angstrom, c = 7.125 to 7.23 angstrom, a = 92.6 degrees to 93.00 degrees, beta = 116.36 degrees to 116.75 degrees, gamma = 90.03 degrees to 90.17 degrees) indicate that their equilibration temperatures are 800 degrees C +/- 10 degrees C. This temperature is near the peak metamorphic temperature recorded by equilibrated ordinary chondrites. The size of plagioclase crystals and the homogeneity of olivine compositions indicate that their petrologic type is >= 5. We also analyzed plagioclase by SR iron X-ray absorption near-edge structure (SR-XANES) and found that its Fe3+/(Fe2+ + Fe3+) ratio is approximately 0.5. Such high Fe3+ abundance indicates the formation under a relatively oxidizing environment. Thus, all these analyses have reconfirmed that the Itokawa particles returned by the Hayabusa spacecraft are very weakly shocked equilibrated LL chondrites, which matches the results of the preliminary examination team

Increase in sedimentary organic carbon with a change from hypoxic to oxic conditions

In the Seto Inland Sea, Japan, chemical oxygen demand has increased over recent decades, while average dissolved oxygen concentrations in the bottom water have increased. In this study, we investigated responses of organic carbon (OC) in hypoxic sediment to changes of redox conditions using experimental columns containing sediment and overlying water. Surface sediment showed an increase in OC along with the change to an aerobic condition. Microbial community analysis showed a predominance of sulfur-oxidizing bacteria (SOB) such as Sulfurovum sp. in the sediment. This dominance could account for the increased OC. Additionally, the dissolved organic carbon (DOC) concentration in the overlying water increased. Further experiments using sandy sediment showed that biodegradation of Sulfurimonas denitrificans was associated with DOC release. These results show that a change in the sedimentary environment (increase in dissolved oxygen) increased the sedimentary OC and DOC of overlying water by stimulating certain autotrophic bacteria, especially the SOB.Peer reviewe

Metabolic implications for predatory and parasitic bacterial lineages in activated sludge wastewater treatment systems

Deciphering unclear microbial interactions is key to improving biological wastewater treatment processes. Microbial predation and parasitism in wastewater treatment ecosystems are unexplored survival strategies that have long been known and have recently attracted attention because these interspecies interactions may contribute to the reduction of excess sludge. Here, microbial community profiling of 600 activated sludge samples taken from six industrial and one municipal wastewater treatment processes (WWTPs) was conducted. To identify the shared lineages in the WWTPs, the shared microbial constituents were defined as the family level taxa that had ≥ 0.1% average relative abundance and detected in all processes. The microbial community analysis assigned 106 families as the shared microbial constituents in the WWTPs. Correlation analysis showed that 98 of the 106 shared families were significantly correlated with total carbon (TC) and/or total nitrogen (TN) concentrations, suggesting that they may contribute to wastewater remediation. Most possible predatory or parasitic bacteria belonging to the phyla Bdellovibrionota, Myxococcota, and Candidatus Patescibacteria were found to be the shared families and negatively correlated with TC/TN; thus, they were frequently present in the WWTPs and could be involved in the removal of carbon/nitrogen derived from cell components. Shotgun metagenome-resolved metabolic reconstructions indicated that gene homologs associated with predation or parasitism are conserved in the Bdellovibrionota, Myxococcota, and Ca. Patescibacteria genomes (e.g., host interaction (hit) locus, Tad-like secretion complexes, and type IV pilus assembly proteins). This study provides insights into the complex microbial interactions potentially linked to the reduction of excess sludge biomass in these processes