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Abstract One mechanism by which the ocean uptakes carbon dioxide is through the biological carbon fixation and its subsequent transport to the deep ocean, a process known as the biological carbon pump. Although the importance of the biological pump in the global carbon cycle has long been recognized, its actual contribution remains uncertain. Here, we quantify the carbon export from the upper ocean via the biological carbon pump by revealing the upper ocean dissolved oxygen balance. Calculations of dissolved oxygen budget quantified net oxygen removals from the upper ocean by physical processes (air–sea exchange, advection, and diffusion) and indicated net biological oxygen production that compensated for those removals. The derived oxygen production is converted to carbon units using the photosynthetic ratio, and inferred an estimated global annual carbon export through the biological pump of 7.36 ± 2.12 Pg C year−1 with providing insights into the overall ocean carbon cycle.

Aim: This study aimed to verify the usability of our newly developed virtual reality-based cognitive function examination (VR-E) to differentiate mild cognitive impairment (MCI) from normal cognition and mild dementia. Method: The subjects of analysis were 71 people (26 males and 45 females, aged from 59 to 94), including 31 with normal cognitive function, 26 with MCI, and 14 with mild dementia, according to the Clinical Dementia Rating (CDR). The total score and each cognitive domain (memory, judgement, spatial cognition, calculation, language function) score of VR-E were compared among CDR0, CDR0.5 and CDR1. In addition, for CDR0 vs. CDR0.5 and CDR 0.5 vs. 1, the areas under the curve (ROC) were examined using the total score and each cognitive domain of VR-E. Results: There were significant differences between the three CDR groups in the VR-E scores as well as each VR-E cognitive domain score. The ROC analysis with an AUC value for the VR-E scores between CDR 0 and 0.5 was 0.71, and between CDR 0.5 and 1 was 0.92. For each VR-E cognitive domain, the ROC analysis with an AUC value between CDR 0 and 0.5 was 0.63 for memory, 0.79 for judgment, 0.70 for spatial cognition, 0.62 for calculation, and 0.57 for language. Between CDR 0.5 and 1, the AUC values were 0.81 for memory, 0.75 for judgment, 0.82 for spatial cognition, 0.88 for calculation, and 0.86 for language. Conclusion: The results suggest that VR-E is useful for differentiating mild cognitive impairment from normal cognition and early dementia.

An observation operator in data assimilation was formalized based on the signatures extracted from the integral quantities contained within observed vertical profiles in the ocean. A four-dimensional variational global ocean data assimilation system, founded on this observation operator, was developed and utilized to conduct preliminary data assimilation experiments over a ten-year assimilation window, comparing the proposed method, namely profile-by-profile matching, with the traditional method, namely point-by-point matching. The proposed method not only demonstrated a point-by-point skill comparable to the traditional method but also provided superior analysis fields in terms of profile shapes on the temperature-salinity plane. This is an indication of a well-balanced analysis field, in contrast to the traditional method, which can produce extremely poor relative errors for certain metrics. Additionally, signatures were shown to successfully represent properties of the water column, such as steric height, and serve as an effective new diagnostic tool. The top-down, or macro–micro, viewpoint in this method is fundamental to the extent that it can offer an alternative view of how we comprehend ocean observations, holding significant implications for the advancement of data assimilation.

Abstract An array of atmospheric profile observations consists of three‐dimensional vectors representing pressure, temperature, and humidity, with each profile forming a continuous curve in this three‐dimensional space. In this paper, the Signature method, which can quantify a profile's curve, was adopted for the atmospheric profiles, and the accuracy of profile representations was investigated. The description of profiles by the signature was confirmed with adequate accuracy. The machine‐learning‐based model, developed using the signature, exhibited a high level of annual accuracy with minimal absolute mean differences in temperature and water vapor mixing ratio (

Plasmablastic lymphoma (PBL) is a type of non-Hodgkin lymphoma commonly associated with human immunodeficiency virus (HIV) infection. In rare cases, PBL occurrence is noted in the oral cavity of elderly individuals who are HIV negative and EBV positive. The present report describes a case of oral mucosa-type PBL that occurred in the maxillary gingiva of the oral cavity. A 91-year-old male came to our clinic with enlarged swelling of the palatal gingiva of the right maxillary molar. The initial examination showed a smooth-surfaced extraordinary swelling with a diameter of approximately 20 mm. Cytology findings led to a class V determination and the patient was clinically diagnosed with a right-sided maxillary malignant tumor. Imaging studies also revealed a tumor in the right-side submandibular lymph node. For further confirmation of the diagnosis, a tissue biopsy was performed and a diagnosis of PBL determined, based on the histopathological and immunohistological findings of the specimen. Blood test results showed that the patient was HIV negative and EBV positive. Two years after the biopsy, there was no recurrence or enlargement in the affected area noted. [ABSTRACT FROM AUTHOR]

The density-compensated salinity anomalies (spiciness anomalies) in the upper North Pacific were investigated using Argo float profiles during 2004–2018. The freshening of the subtropical thermocline was found within the Central Mode Water (CMW) and the North Pacific Intermediate Water (salinity minimum). Meanwhile, the increase of salinity was found in the lighter layer within the North Pacific Tropical Water (salinity maximum). The interannual and longer spiciness anomalies were interpreted with three-dimensional evolutions and were linked to the fate of three mode waters (i.e., Subtropical Mode Water (STMW), Eastern Subtropical Mode Water (ESTMW), and CMW) for the first time. In the STMW, the salinity was dominated by a quasi-decadal variability, which was consistent with the KE variability with a 1-year lag, and did not show rapid freshening. In the CMW, the salinity decreased with a quasi-decadal variability, which was weaker and out of the phase compared with the STMW. In the ESTMW, the salinity was dominated by year-to-year variability. The spiciness anomalies originated mainly in the outcrop region of the isopycnals, where they were accompanied by the formation and the subduction of the mode waters. They also propagated and decayed downstream the geostrophic currents. However, a few of the interannual anomalies found in the northern part of the CMW were almost dampened before their spread further south. In addition, some anomalies in the ESTMW appeared and intensified without a connection to the mixed layer. These anomalies occurred far from the outcrop line, suggesting these were caused likely by salt fingering associated with the modification of the mode waters. Furthermore, the propagation of the spiciness anomalies in the western to the central subtropics was significantly faster than the geostrophic current and inclined to the inner side of streamlines. These indicated the transport by eddies in addition to the mean geostrophic currents.

To elucidate impacts of an Indian Ocean Dipole (IOD) event on surface seawater CO2 dynamics, we analyzed data collected along the World Ocean Circulation Experiment Hydrographic Program I08 N line (latitudes 20°S–6°N at 80°E) in December 2019, when a strong positive IOD (pIOD) event occurred. After removing the effects of anthropogenic CO2 accumulation, we examined anomalies of the surface seawater CO2 fugacity (fCO2) from the climatology in relation to other marine properties. At latitudes 11°S–6°S, where horizontal advection of upwelled water off Sumatra was observed, dissolved inorganic carbon and total alkalinity, both normalized to a salinity of 35 (nTCO2 and nTA) showed positive anomalies of +11.4 and +8.1 μmol kg−1, respectively. At latitudes 5°S–5°N, where distinct low‐salinity water was observed because of the pIOD, nTCO2 and nTA showed negative anomalies of −4.0 and ‒0.5 μmol kg−1, respectively. The combined effects of the nTCO2 and nTA anomalies on fCO2 made the observed fCO2 anomalies small, +3.2 and −6.6 μatm for 6°S–11°S and 5°S–5°N, respectively, because the direction of the Revelle factor for TCO2 is opposite to that for TA. We estimated that the pIOD modulated the air–sea CO2 flux by +0.45 and −0.55 mmol m−2 d−1 on average within11°S–6°S and 5°S–5°N, respectively. The impacts of the pIOD on the CO2 dynamics could be explained by the anomalous salinity conditions associated with upwelled water and the freshwater balance. Plain Language Summary: The Indian Ocean Dipole (IOD) is one of the dominant anomaly patterns in the Indian Ocean, and typically most prominently affects sea surface temperature. In 2019, the strongest IOD of the 21st century occurred. How did this extreme IOD affect the carbon cycle in the ocean? Answering this question was the purpose of this study. To this end, we analyzed data on marine biogeochemical properties observed along 80°E in December 2019. At latitudes 11°S–6°S, where the IOD led to a decrease in sea surface temperature, we detected positive anomalies of dissolved inorganic carbon and total alkalinity relative to their climatological values. In contrast, at latitudes 5°S–5°N, where the IOD led to a decrease in sea surface salinity, we detected small negative anomalies of dissolved inorganic carbon and total alkalinity. These chemical property anomalies individually caused large anomalies in surface seawater CO2 fugacity (fCO2), which determines the potential for air–sea CO2 exchange, but in combination they had only a small effect on fCO2. We found that anomalous salinity conditions due to upwelling and the freshwater balance, both related to the IOD, caused changes in the Indian Ocean CO2 dynamics. Key Points: Significant modulations of marine carbonate system properties during a positive Indian Ocean Dipole were detected along 80°EThe upwelled water advected from off Sumatra increased surface seawater fCO2 and the CO2 flux at latitudes 11°S–6°S at 80°EThe freshwater balance reduced surface seawater fCO2 and the CO2 flux at latitudes 5°S–5°N at 80°E [ABSTRACT FROM AUTHOR]

Abstract A recently developed technique for microstructure measurement based on a fast-response thermistor mounted on a conductivity-temperature-depth equipment was used on eight cruises to obtain 438 profiles. Thus, the spatial distribution of turbulent dissipation rates across the North Pacific sea floor was illustrated, and was found out to be related to results obtained using tide-induced energy dissipation and density stratification. The observed turbulence distribution was then compared with the dissipation rate based on a high-resolution numerical ocean model with tidal forcing, and discrepancies and similarities between the observed and modelled distributions were described. The turbulence intensity from observation showed that the numerical model was overestimated, and could be refined by comparing it with the observed basin-scale dissipation rate. This new method makes turbulence observations much easier and wider, significantly improving our knowledge regarding ocean mixing.

High-accuracy ship-based observations were conducted at 80°E in the Indian Ocean. Salinity below the mixed layer in 2019 was observed to be lower than that in 1995. This decrease in salinity was mainly attributed to anomalous advection associated with one of the strongest positive Indian Ocean dipole (pIOD) events in 2019 through analysis of the gridded time series of the salinity distributions based on the Argo float array. Increases and decreases in nitrate and dissolved inorganic carbon (DIC) and dissolved oxygen (DO), respectively, were also detected on the isopycnal surfaces where decreases in salinity were observed, suggesting that the anomalous upwelling and westward advection associated with the pIOD in the eastern part of the equatorial region resulted in low-salinity, low-oxygen, and nutrient-rich waters in the central off-equatorial region of the Indian Ocean. However, downward isopycnal heaving, which was also associated with the pIOD, was too strong to have increased nitrate below the mixed layers, and thus might have suppressed biological activity. The heaving also affected the DIC and DO distributions, and the effect of interannual changes such as those associated with the Indian Ocean dipole is essential to estimating changes in anthropogenic carbon storage. This research represents a case study, based on only two occupations; therefore, an assessment utilizing more intensive observations and more realistic numerical simulations is necessary in the future.

AbstractRaman spectroscopy of carbonaceous material (RSCM) thermometry is an effective method to determine the thermal structure of metasedimentary domains with high spatial resolution. The mean value of numerous measurements in a single sample is used for temperature estimation. A potential complicating factor is the presence of detrital carbonaceous material (CM) that can introduce bias in the results. Detrital CM generally shows a high degree of crystallinity making it difficult to discriminate detrital and metamorphic CM in high-grade metamorphic domains. Application of the RSCM thermometry to 100 metamudstone samples from the Hongusan area of the Ryoke metamorphic belt reveals multimodal degrees of crystallinity of CM in many samples indicating the common presence of detrital CM grains. Application of a new procedure to filter out the effects of detrital CM reveals a thermal structure that can be explained as the result of the overprinting of two distinct thermal regimes related to regional and subsequent contact metamorphism. The ability to recognize the presence of detrital CM and measure its crystallinity can be used to infer the metamorphic grade present in the hinterland from which the detrital material is derived. A combination of this information on metamorphic temperature with geochemical and radiometric age data reported in the literature indicates that the detrital CM was derived from basement rocks of the Korean Peninsula.

Abstract The Mado Megamullion is an oceanic core complex (OCC) in the Shikoku back‐arc basin within the Philippine Sea Plate. Mantle peridotites (serpentinized) recovered by six dredge and submersible cruises exhibit signatures of extensive deformation. Amorphous pseudomorphs after plagioclase in many of the samples, as well as plagioclase‐spinel intergrowths, are clear evidence of melt stagnation and mantle reaction. Spinels show a wide range of compositions in terms of their Cr#, Mg#, and TiO2 content. The presence of apparently magmatic high‐temperature pargasitic amphibole in veins and as replacement of clinopyroxene suggests that it may be a primary or near‐primary mineral crystallized from a hydrous melt which is unusual for abyssal peridotites. Two trace‐element populations of clinopyroxenes are in equilibrium with depleted and enriched basaltic melts, respectively. Rare‐earth element (REE) in the most depleted clinopyroxenes are modeled by 10% fractional melting except for a ubiquitous La‐Ce “kick.” Multiple models of open system melting combined with subsequent mixing of an enriched melt can explain the REE data. Broadly it appears that the peridotites underwent variable degrees of partial melting with moderate influx of enriched melts, which agrees with the other textural and chemical evidence of melt‐rock reaction and re‐fertilization. The compositions of the accumulated melts simulated by the open system models reproduce the enrichments in fluid mobile elements (Ba, U, and Pb) observed in basalts dredged from the Shikoku basin. Back‐arc basin peridotites at Mado Megamullion appear to have a unique petrographic and geochemical character that is distinct from those of peridotites exposed at the seafloor after formation from mid‐ocean ridges.

In patients with extensive jaw defects, jaw functions, such as mouth opening and occlusion, should be considered during jaw reconstruction in anticipation of implant placement and prosthetic treatment. Herein, we report a case of temporomandibular joint and mandibular bony reconstruction using custom-made trays and particulate cancellous bone and marrow, followed by implant placement. We succeeded in restoring both temporomandibular joint function and occlusion using the reconstruction plate with the condylar head, a mesh tray, and particulate cancellous bone and marrow in a patient with left mandibular reconstruction plate fracture and bony adhesion of the left TMJ. [ABSTRACT FROM AUTHOR]