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A detailed zircon U–Pb (SHRIMP) geochronological study of the amphibolite to granulite-grade rocks of the Rengali Province of eastern India records the growth history of the southern margin of the Singhbhum Craton. Pelitic and mafic granulites from the gneissic belt exhibit contrasting styles of metamorphism. Zircon of the pelitic granulites from the eastern segment yields c. 3528–3064 Ma detrital ages. Charnockitic gneiss from the eastern segment has protolith age of 3058 ± 15 Ma while that from the central segment has protolith age of 2861 ± 30 Ma. The latter rock records high-grade metamorphism at 2818 ± 15 Ma. Hornblende gneiss from the central sector has a protolith age of 2828 ± 9 Ma. Deformed leucogranite in the central and undeformed granitoid in the eastern segment were emplaced at 2807 ± 13 and 2809 ± 13 Ma respectively. The protolith of felsic gneiss from the central sector was emplaced at 2776 ± 24 Ma. Most of the zircon samples contain overgrowths of c. 2500 Ma, inferred to be the age of reworking of the gneissic belt. Our data suggest that the Rengali Province evolved as an orogenic belt in the Neoarchean time (c. 2800–2500 Ma) during southward growth of the Singhbhum Craton. These tectonothermal imprints at the margin of the Singhbhum Craton are possibly related to its inclusion within the supercontinent Ur.

Recent advances in endoscopic technology have allowed its application to middle ear surgery. An antifog agent is necessary for endoscopy because moisture and blood may obscure visibility. Ultrastop is one of the most commonly used antifog agents. The current study examined the ototoxic effect of topical application of Ultrastop in the guinea pig ear.A preliminary experimental animal study.University hospital.Eighteen male Hartley guinea pigs (weight, 480-620 g) were divided into 3 groups to be treated with Ultrastop, gentamicin (50 mg/mL, positive control), or saline solution (negative control). After auditory brainstem responses were measured, topical solutions of 0.2 mL were applied through a small hole made at the tympanic bulla. Posttreatment auditory brainstem responses were obtained 14 days after the treatment. The extent of middle ear damage was investigated and scored.The saline-treated group showed no deterioration in auditory brainstem response threshold. The Ultrastop-treated and gentamicin-treated groups showed severe deterioration in auditory brainstem response threshold. Middle ear examination revealed extensive changes in the Ultrastop-treated group and medium changes in the gentamicin-treated group.Ultrastop applied topically to the guinea pig middle ear caused significant middle ear inflammation and hearing impairment.

Background Diabetes mellitus has been recognized as the most common systemic disease associated with deep neck infection. We report the first systematic review and meta-analysis of the influence of diabetes on clinical and bacteriological characteristics of deep neck infection. Methods Articles were retrieved from PubMed, EMBASE, and the Japan Medical Abstracts Society database. A critical review of 227 studies identified 20 studies eligible for quantitative synthesis. Results Diabetes was associated with higher prevalences of multispace spread of infection, complications, and failure to identify pathogenesis, with risk ratios (RRs) of 1.96, 2.42, and 1.29, respectively. Bacteriologically, patients with diabetes showed a higher prevalence of culture identification of Klebsiella pneumoniae (RR, 3.28), and lower prevalences of Streptococcus spp. (RR, 0.57) and anaerobes (RR, 0.54). Conclusion Deep neck infection with diabetes differs from that without in several clinical aspects. Again, bacteriological differences imply that diabetic infections might be populated by different bacterial flora. © 2014 Wiley Periodicals, Inc. Head Neck 37: 1536–1546, 2015

OT4 zircon collected from Oto-dani quartz diorite in Unazuki, in the northeastern part of the Hida Belt, Southwest Japan, was evaluated using microbeam analysis for its qualification as a Mesozoic reference zircon based on U–Pb dating. The characterization of OT4 zircon was carried out using a sensitive high-resolution ion microprobe (SHRIMP II). Chemical zoning was revealed in some of the grains with a relatively high concentration of U and Th (up to 988 and 1054 ppm, respectively). The weighted mean 206Pb/238U age corrected by 207Pb was 191.1 ± 0.3 Ma (95% confidence limit) and was found to be almost constant for all the grains. The high crystallinity, the constant REE abundance patterns, and the homogeneous Hf concentrations (8651 ± 466 ppm) indicate that the grains were not affected by any geological events after crystallization. Furthermore, the homogeneous Hf concentrations and consistency of the Ti-in-zircon temperature (733 ± 34°C) and the Zr saturation temperature (728°C) suggest that the OT4 zircon crystallized over a short time. The OT4 zircon contains enough radiogenic 206Pb (>2 ppm) and 207Pb (>0.1 ppm) to be detected by microbeam analysis, which indicates its potential of being an effective Mesozoic reference used in microbeam U–Pb dating.

– The isotopic compositions of Sm and/or Gd of nine documented drill core samples of the Jilin H5 chondrite were determined to study the neutron capture records of individual meteorite samples. All the samples showed significant isotopic shifts of 150Sm/149Sm and/or 158Gd/157Gd corresponding to neutron fluences of (1.3–1.7) × 1015 n cm−2. Considering the short 4π irradiation age of 0.32 Ma during the second stage, the 2π irradiation of 7 Ma during the first stage is the main influence on the Sm and Gd isotopic shifts of the Jilin chondrite. Although a depth dependence of the neutron capture effects was expected from the isotopic variations of 150Sm/149Sm and 158Gd/157Gd in the Jilin chondrite core samples that were possibly drilled perpendicular to the surface of the large object with a radius of >10 m in the 2π-geometry, no clear evidence was observed in this study. The data from the combination of the isotopic shifts between Sm and Gd defined as eSm/eGd suggest that the neutrons produced in the 2π-geometry of the Jilin chondrite follow the similar energy spectra as the neutrons in lunar samples, although the present analytical quality is not enough to discuss a critical discussion for the thermalization of the neutron energy levels.

The discovery of the existence of chain reactions at the Oklo natural reactors in Gabon, Central Africa in 1972 was a triumph for the accuracy of mass spectrometric measurements, in that a 0.5% anomaly in the 235U/238U ratio of certain U ore samples indicated a depletion in 235U. Mass spectrometric techniques thereafter played a dominant role in determining the nuclear parameters of the reactor zones themselves, and in deciphering the geochemical characteristics of various elements in the U-rich ore and in the surrounding rock strata. The variations in the isotopic composition of a large number of elements, caused by a combination of nuclear fission, neutron capture and radioactive decay, provide a powerful tool for investigating this unique geological environment. Mass spectrometry can be used to measure the present-day elemental and isotopic abundances of numerous elements, so as to decipher the past history of the reactors and examine the retentivity/mobility of these elements. Many of the fission products have a radioactive decay history that have been used to date the age and duration of the reactor zones, and to provide insight into their nuclear and geochemical behavior as a function of time. The Oklo fission reactors and their near neighbor at Bangombe, some 30 km to the south-east of Oklo, are unique in that not only did they become critical some 2 × 109 years ago, but also the deposits have been preserved over this period of geological time. The long-term geochemical behavior of actinides and fission products have been extensively studied by a variety of mass spectrometric techniques over the past 30 years to provide us with significant information on the mobility/retentivity of this material in a natural geological repository. The Oklo–Bangombe natural reactors are therefore geological analogs that can be evaluated in terms of possible radioactive waste containment sites. As more reactor zones were discovered, it was realized that they could be classified into two groups according to their burial depth in the Oklo mine-site. Reactor Zones 10, 13, and 16 were buried more deeply, and were therefore less weathered than the other zones. The less-weathered zones are of great importance in mobility/retentivity studies and therefore to the question of radioactive waste containment. Isotopic studies of these natural reactors are also of value in physics to examine possible variations in fundamental constants over the past 2 billion years. © 2007 Wiley Periodicals, Inc., Mass Spec Rev 26:683–712, 2007

Objectives:We propose a novel technique to remove the matrix of cholesteatoma endoscopically after completely filling the mastoid cavity with saline water by perfusion for the appropriate management of labyrinthine fistulas. This “underwater” endoscopic ear surgery (UWEES) technique provides a clear operative field without requiring suction and protects the inner ear from unexpected aeration that may damage its function.Methods:A 3-year-old boy was diagnosed with congenital cholesteatoma in a group medical examination. Once the surgery was scheduled but suspended due to the Great East Japan Earthquake. At the age of 6 years, computed tomography revealed a fistula of the superior semicircular canal and surgery was performed for removal of the cholesteatoma and closure of the fistula. Retroauricular incision was chosen because of the extensive lesion, using an intact canal skin method with soft wall reconstruction. The cholesteatoma was extirpated except for the island lesion of the matrix over the fistula ...

— The isotopic compositions of Sm and Gd in seven lunar samples from the Apollo 15 deep drill core were determined to discuss the effects of neutron capture near the lunar surface. Large isotopic deviations of 150Sm/149Sm, 156Gd/155Gd, and 158Gd/157Gd derived from neutron capture effects were observed in all samples. Although neutron capture products in lunar samples were investigated extensively in the 1970s, our precise isotopic measurements resulted in several new findings. The neutron fluence in the Apollo 15 drill core is a function of depth with a symmetric peak at 190 g/cm2 depth from the surface, confirming the results of earlier investigations. Neutron fluence values calculated from the isotopic shifts by comparison to artificially irradiated standard reagents were (5.16–7.49) × 1016 n/cm2. These values are 1.3 to 1.4x larger than those previously reported. Variations of eSm/eGd with depth are interpreted as being due to variations in the neutron energy spectrum. Here eSm and eGd are defined as in previous studies of lunar neutron stratigraphy. Our data suggest that the neutron is more thermalized at the lower layers than it is at the upper layers. In addition to large isotopic shifts for 149Sm, 150Sm, 155Gd, 156Gd, 157Gd, and 158Gd, isotopic enrichments of 152Gd and 154Gd derived from neutron capture for 151Eu and 153Eu, respectively, were also observed in all samples.