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Initial analyses showed that asteroid Ryugu's composition is close to CI (Ivuna-like) carbonaceous chondrites (CCs) - the chemically most primitive meteorites, characterized by near-solar abundances for most elements. However, some isotopic signatures (for example, Ti, Cr) overlap with other CC groups, so the details of the link between Ryugu and the CI chondrites are not yet fully clear. Here we show that Ryugu and CI chondrites have the same zinc and copper isotopic composition. As the various chondrite groups have very distinct Zn and Cu isotopic signatures, our results point at a common genetic heritage between Ryugu and CI chondrites, ruling out any affinity with other CC groups. Since Ryugu's pristine samples match the solar elemental composition for many elements, their Zn and Cu isotopic compositions likely represent the best estimates of the solar composition. Earth's mass-independent Zn isotopic composition is intermediate between Ryugu/CC and non-carbonaceous chondrites (NCs), suggesting a contribution of Ryugu-like material to Earth's budgets of Zn and other moderately volatile elements.

In the Palghat–Cauvery Shear/Suture Zone of the Southern Granulite Terrane, the Sittampundi Layered Complex occurs as a mappable unit. The Sittampundi Layered Complex consists of mafic, ultramafic and anorthositic rocks with chromitite layers and has been interpreted as an arc/ophiolite complex that formed in an Archaean suprasubduction zone arc setting. In the Sittampundi Layered Complex, reddish-black metabasites occur as layers or boudins with a rim of amphibolite within anorthosite. The peak metamorphic assemblage of the metabasites is garnet + clinopyroxene + quartz + rutile ± plagioclase ± orthopyroxene, and symplectite consisting of amphibole and plagioclase formed around the garnet during retrograde metamorphism. The protolith of metabasite may have intruded in a suprasubduction zone arc setting during the late Neoarchaean (c. 2540–2520 Ma), and then underwent high-pressure granulite-facies peak metamorphism (900–800 °C and 11–14 kbar) in the early Palaeoproterozoic (c. 2460–2440 Ma), followed by amphibolite-facies metamorphism (550–480 °C and 5.5–4.5 kbar) in the middle Palaeoproterozoic (c. 1900–1850 Ma). The results obtained in this study, together with previous studies, indicate that: (1) the high-pressure granulite-facies metamorphism in the study area indicates that subduction occurred during the Archaean–Proterozoic boundary with a higher apparent average geothermal gradient (∼20–16 °C km−1) than the modern-day Earth, and (2) the apparent average geothermal gradient of the subduction zone was ∼29–14 °C km−1 during the Archaean–Proterozoic boundary, which was still too high to enter the realm of eclogite-facies metamorphism.

A systematic survey was performed for binding energy and reaction path search calculations on ice. ONIOM(⍵B97X-D/Def2-TZVP:AMOEBA09) calculations suggested a range of binding energies for CH2OH radical (0.29 – 0.69 eV)...

Correction to: Nature Astronomy https://doi.org/10.1038/s41550-022-01846-1. Published online 12 December 2022.

This is an update of the 2015 Guidelines developed by the Japan Otological Society and Oto-Rhino-Laryngeal Society of Japan defining otitis media with effusion (OME) in children (younger than 12 years old) and describing the disease rate, diagnosis, and method of examination. Recommended therapies that received consensus from the guideline committee were updated in consideration of current therapies used in Japan and based on available evidence.Regarding the treatment of OME in children, we developed Clinical Questions (CQs) and retrieved documents on each theme, including the definition, disease state, method of diagnosis, and medical treatment. In the previous guidelines, no retrieval expression was used to designate a period of time for literature retrieval. Conversely, a literature search of publications from March 2014 to May 2019 has been added to the JOS 2015 Guidelines. For publication of the CQs, we developed and assigned strengths to recommendations based on the collected evidence.OME in children was classified into one group lacking the risk of developing chronic or intractable disease and another group at higher risk (e.g., children with Down syndrome, cleft palate), and recommendations for clinical management, including follow-up, is provided. Information regarding management of children with unilateral OME and intractable cases complicated by adhesive otitis media is also provided.In clinical management of OME in children, the Japanese Clinical Practice Guidelines recommends management not only of complications of OME itself, such as effusion in the middle ear and pathologic changes in the tympanic membrane, but also pathologic changes in surrounding organs associated with infectious or inflammatory diseases.

Alteration of iron sulfides on the lunar surface by space weathering is poorly understood. We examined space weathering features of iron sulfides in lunar mature soil grains using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). SEM observations reveal that iron sulfides have vesicular textures and iron whiskers on their surfaces. Iron sulfides observed using TEM are troilite and NC-pyrrhotite. The space-weathered rim on the iron sulfides is characterized by crystallographic misorientations and the disappearance of superstructure reflections of troilite in electron diffraction patterns. These crystallographic modifications are probably produced by solar wind irradiation. The rim contains opened vesicles that are aligned along the c-plane of the sulfides, as well as numerous tiny vesicles. The Fe/S ratio at the surface of the rim is higher than in non-altered regions, indicating selective sulfur loss from the surface. Iron whiskers protrude from the space weathered rim and consist of polycrystalline metallic iron. The sulfide rims and the iron whiskers are both coated with vapor-deposited materials rich in O and Si. The combined processes driven by the solar wind irradiation, heating during impact events, solar UV radiation, and the thermal cycling may cause vesicular textures, selective sulfur escape from the iron sulfides, and the formation of the iron whiskers. The rim textures support the notion that the enrichment of heavy sulfur isotopes in mature lunar soils is caused by space weathering of iron sulfides. The space weathered rims on lunar iron sulfides are similar to those observed in regolith samples from asteroid Itokawa. Therefore, alterations of sulfide surface might be common among airless bodies in the solar system.

Carbonaceous meteorites are thought to be fragments of C-type (carbonaceous) asteroids. Samples of the C-type asteroid (162173) Ryugu were retrieved by the Hayabusa2 spacecraft. We measured the mineralogy and bulk chemical and isotopic compositions of Ryugu samples. The samples are mainly composed of materials similar to those of carbonaceous chondrite meteorites, particularly the CI (Ivuna-type) group. The samples consist predominantly of minerals formed in aqueous fluid on a parent planetesimal. The primary minerals were altered by fluids at a temperature of 37° ± 10°C, about 5.2 − 0.7 + 0.8 million (statistical) or 5.2 − 2.1 + 1.6 million (systematic) years after the formation of the first solids in the Solar System. After aqueous alteration, the Ryugu samples were likely never heated above ~100°C. The samples have a chemical composition that more closely resembles that of the Sun’s photosphere than other natural samples do.

The surface processes on interstellar dust grains have an important role in the chemical evolution in molecular clouds. Hydrogenation reactions on ice surfaces have been extensively investigated and are known to proceed at low temperatures mostly below 20 K. In contrast, information about the chemical processes of molecules within an ice mantle is lacking. In this work, we investigated diffusive hydrogenation reactions of carbon monoxide (CO) embedded in amorphous solid water (ASW) as a model case and discovered that the hydrogenation of CO efficiently proceeds to yield H2CO and CH3OH even above 20 K when CO is buried beneath ASW. The experimental results suggest that hydrogen atoms diffuse through the cracks of ASW and have a sufficient residence time to react with embedded CO. The hydrogenation reactions occurred even at temperatures up to ~70 K. Cracks collapse at elevated temperatures but the occurrence of hydrogenation reactions means that the cracks would not completely disappear and remain large enough for penetration by hydrogen atoms. Considering the hydrogen-atom fluence in the laboratory and molecular clouds, we suggest that the penetration of hydrogen and its reactions within the ice mantle occur in astrophysical environments. Unified Astronomy

Objective To perform a systematic review and meta-analysis of surgical outcomes following repair of patulous Eustachian tube (PET). Data sources Analysis of cases collected from studies published between January 1990 and December 2018 and identified using PubMed, Google Scholar, and Cochrane databases. Study selection Articles addressing interventions to treat PET were selected. Data extraction The database was searched using the keywords "patulous Eustachian tube treatment" and yielded 1,370 studies. Twenty studies were eligible for inclusion. Data synthesis A total of 914 cases were evaluated for surgical approach, patient outcomes, and complications. The reported techniques were categorized by the procedure type, including ventilation tube insertion, mass loading of the tympanic membrane, ET injection, plug surgery, shim surgery, tuboplasty, and ET closure. Overall PET symptom improvement were reported for ventilation tube insertion (79 cases, mean: 58%, 95% CI: 47-69%), mass loading of the tympanic membrane (43 cases, mean: 50%, 95% CI: 32-69%), ET injection (139 cases, mean: 47%, 95% CI: 38-56%), plug surgery (386 cases, mean: 81%, 95% CI: 77-85%), shim surgery (122 cases, mean: 62%, 95% CI: 53-70%), tuboplasty (105 cases, mean: 41%, 95% CI: 31-51%), and ET closure (40 cases, mean: 66%, 95% CI: 49-80%). A low incidence of minor complications was reported. Conclusions This systematic review describes clinical outcome data following surgical management of PET. Plug surgery and shim surgery show relatively high effectiveness and safety. Further prospective studies that compare surgical approaches for PET are needed.

Background: Detailed investigations of the stapedial muscle (SM) in congenital aural atresia (CAA) patients have yet to be adequately conducted.Objectives: To assess image variations in the mastoid...

To examine the evidence for treating children with otitis media with effusion with pharmacotherapy.For the systematic review, data were retrieved from PubMed, Cochrane database, and the Japan Medical Abstracts Society Database (1st January 1995 through 31th May 2019).Articles addressing pharmacotherapy for the management of otitis media with effusion in children were selected in English.The database was searched using the keywords "Otitis Media with effusion or secretory otitis media" and the following medical agents: carbocysteine, antihistamines, leukotriene receptor antagonist, and steroid nasal spray.After a critical review of 18 studies, studies addressing steroid nasal spray were eligible for quantitative synthesis. Intranasal steroids for OME showed no benefit with OR 1.155 (95% CI 0.834-1.598) within one month. Conversely, intranasal steroids have effects for OME with OR 1.858 (95% CI 1.240-2.786) for more than one month.We found evidence of benefit from treatment of OME in children with intranasal steroids and S-carboxymethylcysteine at longer-term follow-up.

In far North Greenland at the head of Victoria Fjord (∼81°30′N), a ∼1000 km2 exposure of Precambrian crystalline basement rocks is a window through the region's extensive latest Neoproterozoic and Paleozoic Arctic Platform sedimentary cover sequence. These basement rocks, named here the Victoria Fjord terrane, are dominated by weakly-foliated granodioritic orthogneisses, with lesser amounts of migmatite. These are intercalated with strips of supracrustal rocks dominated by paragneisses. This poorly-exposed Archean terrane at Greenland's northern tip is succeeded to the south by the extensive east-west trending Paleoproterozoic Inglefield Mobile Belt of juvenile arc rocks. The Victoria Fjord terrane granodiorites have zircon U-Pb ages from 3292 ± 14 Ma to ∼3260 Ma. Reconnaissance U-Pb dating on schlieric migmatite zircons yielded ages of ∼3280, 3400 and 3500 Ma. Paragneiss detrital zircons have ages of mostly ∼2710 Ma, with a minority of 3000–2900 Ma grains. This demonstrates that these sedimentary rocks were not derived from the local basement. Post- Archean magmatic or metamorphic zircon was not detected in any of the samples. Initial eHf of 3290–3260 Ma granodiorite and granite zircons ranges from −4 to +2, and the magmatic protoliths are interpreted as sourced from the melting of somewhat older (3500–3400 Ma) Paleoarchean crust, represented by paleosome in the migmatites. The paragneiss 3000–2900 Ma detrital zircons were derived from juvenile felsic crust of that age. The ∼2710 Ma group show negative correlation of Th/U and initial eHf, such that those with high Th/U up to >2.0 have eHf values of −6 to −10. The ∼2710 zircons were sourced from mafic rocks formed by melting of much older (Paleoarchean?) enriched mantle which was variably contaminated by 3000–2900 Ma crust during its ascent. The Victoria terrane is unique amongst the Archean basement terranes in Greenland because it is dominated by 3500–3260 Ma crust. However, the Arctic basin contains detrital zircons of that age, and rocks of that age also occur in eastern Siberia and northwestern Canada. Implications for high Arctic early Precambrian geodynamics are discussed.

BACKGROUNDS Data on risk factors for deep neck infection including descending necrotizing mediastinitis (DNM) have been limited. Using a nationwide database, the aim was identifying the factors related to patient death and delay in recovering oral intake. METHODS Data of 4949 patients were extracted from a Japanese inpatient database between 2012 and 2017. The main outcome was survival at discharge. In a subgroup analysis of the 4949 patients with survival, the second outcome was delay in the interval between admission and full recovery of oral intake. RESULTS Only a few factors (advanced-age, ventilation) were associated with both mortality and delayed oral dietary intake by logistic regression analyses. Conversely, several factors including DNM (adjusted-odds ratio [OR] 1.41) and repeated surgery (adjusted-OR 1.70) were significantly related only to delayed oral dietary intake. CONCLUSIONS Although DNM was not necessarily related to mortality, patients with DNM should receive careful attention to avoid delayed oral dietary intake.

Three structural isomers of the C2H4O2 molecule, namely, methyl formate (MF; HCOOCH3), acetic acid (AA; CH3COOH), and glycol aldehyde (GA; HOCH2CHO), have attracted considerable attention as targets for understanding pathways towards molecular complexity in the interstellar medium (ISM). Among these isomers, MF is decisively abundant in various astronomical objects. For various formation pathways of MF, surface reactions on cosmic dust would play an important role. However, when compared to observations, the formation of MF has been found to be relatively inefficient in laboratory experiments in which methanol (CH3OH)-dominant ices were processed by ultraviolet (UV) photons and cosmic-ray analogues. Here, we show experimental results on the effective formation of MF by the photolysis of CH3OH on water ice at 10 K. We found that the key parameter leading to the efficient formation of MF is the supply of OH radicals by the photolysis of H2O, which significantly differs from CH3OH-rich experimental conditions. Moreover, using an ultra-high-sensitivity surface analysis method, we succeeded in constraining the decisive formation pathway of MF via the photolysis of methoxymethanol (MM; CH3OCH2OH), which would improve our current understanding of chemical evolution in the ISM., Comment: Accepted in ApJL; 10 figures including 5 figures in Appendix

Binding energies of the CH

Isotopic analyses of elements in the natural reactor materials have often been performed to understand the distribution behaviors of the fission products and to evaluate the function of nuclear reactions since the first discovery of a natural reactor in 1972. Several types of unique microminerals, including significant amounts of fission products, have been found in and around the Oklo and the Bangombé natural reactors. In the past two decades, microbeam techniques using ion and laser probe facilities have been effectively applied for the in situ isotopic analyses of individual microminerals to investigate the migration behaviors of fissiogenic radioisotopes produced in the reactors. This paper presents a review of interpretations of the isotopic results of microminerals found in and around the natural reactors.

Backgrounds: Data on risk factors for deep neck infection (DNI) including descending necrotizing mediastinitis (DNM) have been limited. Using a nationwide database, the aim was to identify the factors related to patient death and delay in recovering oral intake.Methods: We retrospective reviewed a Japanese inpatient database between 2012 and 2017, and data of 4,949 patients with DNM and DNI were extracted. The main outcome was survival at discharge. In a subgroup analysis of the 4,791 patients with survival at discharge, the second outcome was delay in the interval between admission and full recovery of oral intake. In both of the setting, logistic regression analyses were conducted to determine the risk factors.Results: Regarding survival at discharge, logistic regression analysis showed that age (≥75 years), comorbid diabetes mellitus, sepsis, receiving mechanical ventilation, and duration of empirical antibiotic therapy were significantly associated with mortality [adjusted-odds ratios (ORs) (95% confidence intervals (CIs)] as follows: 5.57 (2.80-11.1), 2.47 (1.69-3.62), 3.32 (2.29-4.82), 3.96 (2.51-6.23), and 1.00 (1.00-1.02), respectively. In a subgroup analysis of the 4,791 patients with survival at discharge, logistic regression analysis showed the following factors to be significantly associated with delayed oral dietary intake (>9 days), as follows [adjusted OR (95% CIs)]: age ≥75 years 1.89 (1.48-2.41); body mass index (BMI) 2 1.39 (1.13-1.71); DNM 1.41 (1.04-1.92); repeated surgical interventions 1.70 (1.16-2.48); tracheotomy 1.70 (1.44-2.00); mechanical ventilation 1.92 (1.53-2.41); intensive care unit (ICU) admission 1.54 (1.22-1.93); rehabilitation for oral dietary intake 2.05 (1.44-2.92); and duration of empirical antibiotic therapy 1.18 (1.17-1.20).Conclusions: In this study, a few factors (advanced age, ventilation) were associated with both mortality and delayed oral dietary intake. Conversely, several factors including DNM and repeated surgery were significantly related only to delayed oral dietary intake. Although DNM was not necessarily related to mortality, patients with DNM should receive postoperative care with careful attention to avoid delayed oral dietary intake.

Cosmic-ray exposure records of 13 lunar meteorites, Dhofar 081, Dhofar 910, Dhofar 911, Northwest Africa (NWA) 482, NWA 2995, NWA 2996, NWA 3136, NWA 3163, NWA 4472, NWA 4734, NWA 4884, NWA 4932, and NWA 4936, were characterized from the abundances of spallogenic (10Be and 26Al) and neutron-captured (36Cl, 41Ca,150Sm, and 168Er) nuclides produced by cosmic-ray irradiation. Assuming a single-stage irradiation model for individual meteorites, 11 of the 13 meteorites had resided at shallow depths in the range of 55 to 330 g cm−2 from the lunar surface and experienced cosmic-ray irradiations for 140–870 Ma on the Moon. In contrast, 2 of the 13 meteorites, Dhofar 911 and NWA 4932, cannot be simply explained by a single-stage irradiation, but need at least two-stage irradiation on the Moon. Furthermore, the neutron fluences of thermal and epithermal energy regions for individual meteorites were quantified from a combination of the isotopic shifts of 149Sm–150Sm and 167Er–168Er, respectively. Our estimates gave 8–11 times higher epithermal neutron fluences (1.7–13.7 × 101 7 neutrons cm−2) than the thermal neutron fluences (0.65–13.8 × 1016 neutrons cm−2) for 9 of the 13 meteorites, which are consistent with those from the lunar regolith materials in our previous study. This result also supports the long cosmic-ray irradiation of most lunar meteorites on the surface of the Moon.

The Spongtang Massif is a remnant of Neotethyan ocean crust emplaced onto the Indian passive margin along the Indus-Yarlung-Tsangpo Suture in the NW Himalayan region of Ladakh. The age, tectonic evolution and timing of ophiolite obduction are critical to our understanding of the mechanisms via which entire oceans are formed, consumed and partly preserved before the onset of terminal continent-continent collisions. Geochemistry of the gabbro and basaltic units suggest the presence of both MORB-type and primitive arc-related mafic rocks. Zircons extracted from the Spongtang Massif gabbros yield U-Pb (SHRIMP) ages of 136–133 Ma with initial eHf values of +14 to +16, indicating Early Cretaceous juvenile, depleted mantle sources devoid of contamination by older continental crust. Previously, Middle Jurassic (~177 Ma) zircon ages were obtained from gabbro and we suggest these represent MORB-type Neotethyan oceanic crust through which a younger intra-oceanic island-arc (Spong arc) developed in response to subduction initiation during the Early Cretaceous (~136 Ma). Our zircon ages are consistent with Early Cretaceous ages obtained for radiolarian cherts within the Spong Arc complex. Subduction beneath the Spong Arc continued until its collision with the northern Indian continental margin during the early Eocene. We suggest that the Spongtang Massif is equivalent to the nearby Dras island arc terrane. Intra-oceanic subduction beneath this system was possibly initiated along NNE-SSW trending transform faults in the Neotethyan Ocean, along which different ages of ocean crust was juxtaposed, thereby development of the Early Cretaceous Spong Arc is superimposed on the older Jurassic Spongtang N-MORB crust. The juvenile ɛHf signature indicates the subduction system that spawned the Spong island arc was not related to the coeval Trans-Himalayan (Ladakh-Gangdese) arc that developed along the southern margin of Eurasia. The age, composition and nature of geological relationships with the underlying Indian rocks indicate the Spong Arc was a juvenile, intra-oceanic terrane that first collided with India before the onset of final continent-continent collision. Therefore, final late Eocene Neotethys closure was between the Kohistan-Ladakh (Eurasian) continental arc and the already inactive Indian + Spongtang margin.

We present zircon U-Pb (SHRIMP) and monazite U-Th-total Pb (EPMA) ages from a suite of high-grade rocks of the Phulbani domain of the Eastern Ghats Belt, India. These ages are integrated with the metamorphic and magmatic histories of the Phulbani domain to put precise time constraints on the tectonothermal evolution of the northern part of the Eastern Ghats Belt. Zircon from the coarse-grained charnockite rock shows crystallization age of ca. 970 Ma. Aluminous granulite contains spinel and quartz-bearing mineral assemblage indicating ultrahigh temperature metamorphism (>900 °C at 8–10 kbar) which possibly occurred during ca. 987 Ma as revealed from monazite included in porphyroblastic garnet. Monazite in the aluminous granulite and the migmatitic felsic gneiss grew dominantly at 966 ± 4 Ma and 968 ± 4 Ma ages respectively, which are interpreted as the cooling ages subsequent to peak metamorphism. Oscillatory-zoned zircon grains of the felsic augen gneiss yield ca. 1173 Ma age which is interpreted as the crystallization age of the granitic protolith. This ca. 1173 Ma age granite possibly composed a part of the Proterozoic basement of the Eastern Ghats Province. A monazite age of 781 ± 15 Ma from the aluminous granulite may indicate the timing of a localized shear-induced thermal process in the Phulbani domain. The presently studied rock suite thus recorded three distinct events (ca. 1173 Ma, ca. 1000–900 Ma and ca. 781 Ma) of magmatism, metamorphism and deformation of Eastern Ghats Belt. Metamorphic and magmatic histories of the Phulbani domain are similar to those of the adjacent Visakhapatnam domain and the Rayner Province of East Antarctica during the time frame ca. 1000–900 Ma.

Sinus fungal ball is defined as noninvasive chronic rhino-sinusitis with a clump of mold in the paranasal sinuses, typically affecting the maxillary sinus. Fairly good outcomes of endoscopic surgery have been reported where the ball is removed through the antrostomy. However, the affected sinus tends to have a smaller cavity and thicker bony walls. As such, it is often challenging to maintain a window size that is sufficient to control possible recurrence. The endoscopic modified medial maxillectomy procedure was applied to a 61-year old and a 70-year old female patient with maxillary sinus fungal ball. Using this method, we created a much larger inferior meatal antrostomy without difficulty. The window provided us with an endoscopic view of the whole sinus and complete eradication of the lesion. Endoscopic modified medial maxillectomy is useful as a surgical procedure for maxillary sinus fungal ball and should be considered for better outcomes.