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Nasopalatine duct cysts are the most common non-odontogenic cysts in the maxilla, and are conventionally treated through a sublabial or palatine approach. Recently, the endoscopic approach has been used, but experience is extremely limited. We treated a 29-year-old male with nasopalatine duct cyst by endoscopic marsupialization, but paresthesia of the incisor region occurred after surgery. This paresthesia gradually remitted within 6 months. The nasopalatine nerve, which innervates the upper incisor region, enters two lateral canals separately at the nasal floor and exits the central main canal at the palate. Damage to the bilateral nasopalatine nerves might lead to paresthesia, so we recommend careful examination for nerve fibers during endoscopic surgery, especially if fenestration is performed on both sides.

Europium isotopic composition could be a good probe to investigate the neutron capture process in Asymptotic Giant Branch stars (AGB stars) and/or supernovae, because the 151 Sm and 153 Sm branchings are sensitive to the neutron densities and temperature. Here, we report Eu isotopic analyses of single SiC grains from primitive meteorites using the sensitive high resolution ion microprobe (SHRIMP). The results are compared with Eu isotopic ratios predicted from the recently determined 151 Sm( n , γ ) cross-sections and the thermally pulsed s-process model of AGB stars. The observed Eu isotopic composition of SiC grains place constraints on s-process conditions such as the temperature and neutron densities in AGB stars.

Enstatite achondrites (aubrites) when compared to other stone meteorites have unusually long cosmic-ray exposure (CRE) ages. We report here the 150 Sm/ 149 Sm and 158 Gd/ 157 Gd ratios in six different structural phases, i.e., light and dark (shocked) grains and in matrix materials of Pesyanoe, in three different fragments from Pena Blanca Spring, and in one from Norton County, Shallowater, and Khor Temiki, to investigate the regolith history on the aubrite parent body. The results from phases components of Pesyanoe confirm earlier reported evidence for regolith irradiation of several aubrites. The inferred neutron fluences for six Pesyanoe separates vary between (2.13 and 2.82) × 10 16 n cm −2 . The fluences also significantly exceed those expected from cosmic-ray irradiation during transit to Earth and approach those observed in the lunar regolith. These observations confirm that the brecciated Pesyanoe meteorite, which contains solar wind (SW) gases only in dark phases, was processed in a regolith and that structural phases were differentially irradiated before compaction. On the other hand, in some aubrites (Mt. Egerton, Shallowater, Pena Blanca Spring, Norton County) neutron capture effects may entirely be due to space irradiation.

The polymict Kamiaso Conglomerate (Mino Terrane, Japan) contains Jurassic to Palaeoproterozoic clasts—probably derived from Korean basement that lay nearby to the northwest at time of deposition. Clast K2 broke cleanly into two halves during sampling (but the halves were recombined for zircon separation). A third of the K2 zircons are colourless euhedral prisms with oscillatory zoning, with no inheritance and yielded a SHRIMP U/Pb date of 743±17 Ma. Two thirds of K2 zircons are brown oscillatory-zoned corroded prisms with a date of 1860±8 Ma, with inherited cores up to ∼2460 Ma. A likely explanation for this could be that clast K2 might have been composite, and contained undistinguished 743 Ma and 1860 Ma granites. Kamiaso granitic clast K3 igneous zircons gave a date of 179.3/−2.1 Ma (Toarcian–Early Jurassic), with 2100–2300 Ma and ∼1860 Ma inherited cores. ∼740 Ma A-type magmatism related to the extension and break up of Rodinia occurs in both Korea (Gyeonggi Block) and the main part of the South China Craton, but is unknown in the Sino-Korean Craton. Thus from recognition of a 743 Ma clast, the Kamiaso detritus was probably derived from the northernmost part of the South China Craton in Korea.

Isotopic analyses of U, Pb and REE in 144 zircon grains from the Bidoudouma stream, the Republic of Gabon, were performed to study correlation of elemental distribution with geological alteration effects. The U–Pb isotopic results reveal that the zircons formed around 2.8–2.1 Ga ago and altered around 500 Ma ago by igneous activity in association with dolerite dyke intrusion. The REE abundance patterns of the U–Pb discordant zircons are characterized by high contents of REE (977–98,154 ppm), small LREE–HREE fractionations and distinctly positive Eu anomalies. The discordant zircons also contain significant amounts of non-formula elements such as Ca, Mn, Al and Fe; whereas, their contents of Zr and Si are 1–15% lower than those of concordant zircon. Non-formula elements and REE, especially LREE, were incorporated into metamict zircon in association with Pb-loss, which indicates that the non-formula elements and REE substituted for Zr and Si. Judging from this correlation among the contents of non-formula elements, when zircon was initially altered, Fe substituted for major elements of zircon. After the saturation of Fe, Ca and Mn were incorporated into zircon together with REE and Al followed by Ca. The metamict zircons contain large amount of U (∼8215 ppm), which indicates that U had not migrated from zircon grain in association with the Pb-loss.

The Commission on Atomic Weights and Isotopic Abundances of the International Union of Pure and Applied Chemistry completed its last review of the isotopic compositions of the elements as determined by isotope-ratio mass spectrometry in 2001. That review involved a critical evaluation of the published literature, element by element, and forms the basis of the table of the isotopic compositions of the elements (TICE) presented here. For each element, TICE includes evaluated data from the “best measurement” of the isotope abundances in a single sample, along with a set of representative isotope abundances and uncertainties that accommodate known variations in normal terrestrial materials. The representative isotope abundances and uncertainties generally are consistent with the standard atomic weight of the element Ar(E) and its uncertainty U[Ar(E)] recommended by CAWIA in 2001.

Summary In order to investigate migration behavior of REE in uranium matrix by alteration, and to understand a chronological history of the alteration processes, in-situ isotopic analysis of U, Pb and REE by using a Sensitive High Resolution Ion MicroProbe (SHRIMP) was applied to the Koongarra uranium deposit sample (Northern Territory, Australia) which contains uraninite and two kinds of secondary uranium minerals (curite and sklodowskite). Highly discordant U-Pb data from all of the uranium minerals suggest that the secondary uranium minerals were formed by sequential alteration of primary uraninite 50-580 Ma ago, and subsequently affected by recent weathering. The difference of REE abundance patterns between primary uraninite and secondary uranium minerals show geochemical evidence of REE redistribution during the secondary mineralization by the interaction of primary ore body with meteoric water.

Through the use of acid digestion and a modified distillation procedure the Ru contents in various terrestrial minerals have been determined via the stable isotope dilution mass spectrometry (IDMS) method, with isotopic analysis carried out via inductively coupled plasma mass spectrometry (ICP-MS) and negative thermal ionization mass spectrometry (N-TIMS). The uncertainties in the concentrations ranged from 2.1% to 6.0% (2σ) for ppb and ppm samples concentrations, which is comparable and in some cases better than previous work using NiS fire assay and ICP-MS (Shirai et al., 2003). However, uncertainties for ppt samples were in around 20%, due to low count rates during analysis. Results from three different mineral species show the effectiveness of this chemical dissolution and separation procedure for samples of varying Ru concentrations, ranging from ppm down to ppt levels, and varying geological matrices, from sulphides to silicates. Ru abundances measured showed results consistent with the siderophile nature of Ru, and reinforces the similarity in melt chemistry between Ru and Os.

Mineralogical and isotopic studies were carried out on the natural nuclear reaction zone 2 from the Oklo deposit to evaluate the mobility of several nuclear reaction products in response to the alteration of the reaction zone and to identify the mechanisms which could retard the transport of released radionuclides. To address these issues, in situ isotopic analyses by SHRIMP and a selective extraction procedure were performed to constrain the structural location of nuclear reaction products (exchangeable and non exchangeable) and their association with mineral phases. The distribution patterns of U, REE, Zr and Mo isotopes reveal that substantial amounts were released from the core and migrated through the hydrothermal alteration halo over metric distances, owing to uraninite dissolution and advective transport by hydrothermal solutions during and soon after criticality. The results emphasize the mobility of Zr at Oklo, this element being often considered as “immobile” during water–rock interactions. The main output is the demonstration of the net effects of sorption and coprecipitation processes. Chlorite and to a lesser extent illite were found to have adsorbed significant amounts of U, REE, Zr (and probably Th) and less sorbing elements such as Mo. Coprecipitation of secondary UO2 and P-rich coffinite within the alteration halo is also an important means of retardation. The concentration of radionuclides released from the reactor were probably high and they display solubility limited transport behaviour. No retention effect was found for Se in the immediate vicinity of the reactor and this element may have moved farther from its source of production. These results have interesting implications for the evaluation of long-term containment of radionuclides. They provide a simple illustration of the performance of a clay barrier in the uptake of radionuclides by sorption onto clays and reincorporation in secondary U-minerals. This study also demonstrates the robustness of these retention processes over extremely long periods of time.

The Ba isotopic composition of primitive meteorites is one of the more useful tracers to study nucleosynthetic processes in the early solar system, because the seven stable Ba isotopes consist of p-, r-, and s-process nucleosynthetic components and possible decay products from presently extinct 135 Cs. Ba isotopic analyses were performed on acid leachates from five carbonaceous chondrites, Murchison (CM2), Sayama (CM2), Allende (CV3), Isuna (CO3) and Maralinga (CK4), and one basaltic achondrite, Juvinas (Eucrite). The Ba isotopic data of acid treatment fractions in carbonaceous chondrites suggest the presence of independent nucleosynthetic components for s- and r-processes in the solar system. The isotopic patterns from the acid residual fractions of two CM2 meteorites, Murchison and Sayama, show an enrichment of s-process isotopes, which is similar to that of presolar SiC grains. On the other hand, their acid leachates have an excess of r-process components among the Ba isotopes. In many cases of carbonaceous chondrites other than CM meteorites, the excess of r-process isotopes is too small for a detailed discussion about the nucleosynthetic contribution. This may be interpreted as metamorphic destruction of presolar grains in meteorite matrices associated with petrographic-type meteorites. Juvinas shows no isotopic anomalies of Ba, because the isotopic record in the early solar system was reset possibly by magmatic processes in the parent body.

A consistent set of internationally accepted atomic weights has long been an essential aim of the scientific community because of the relevance of these values to science and technology, as well as to trade and commerce subject to ethical, legal, and international standards. The standard atomic weights of the elements are regularly evaluated, recommended, and published in updated tables by the Commission on Atomic Weights and Isotopic Abundances (CAWIA) of the International Union of Pure and Applied Chemistry (IUPAC). These values are invariably associated with carefully evaluated uncertainties. Atomic weights were originally determined by mass ratio measurements coupled with an understanding of chemical stoichiometry, but are now based almost exclusively on knowledge of the isotopic composition (derived from isotope-abundance ratio measurements) and the atomic masses of the isotopes of the elements. Atomic weights and atomic masses are now scaled to a numerical value of exactly 12 for the mass of the carbon isotope of mass number 12. Technological advances in mass spectrometry and nuclear-reaction energies have enabled atomic masses to be determined with a relative uncertainty of better than 1 ×10−7 . Isotope abundances for an increasing number of elements can be measured to better than 1 ×10−3 . The excellent precision of such measurements led to the discovery that many elements, in different specimens, display significant variations in their isotope-abundance ratios, caused by a variety of natural and industrial physicochemical processes. While such variations increasingly place a constraint on the uncertainties with which some standard atomic weights can be stated, they provide numerous opportunities for investigating a range of important phenomena in physical, chemical, cosmological, biological, and industrial processes. This review reflects the current and increasing interest of science in the measured differences between source-specific and even sample-specific atomic weights. These relative comparisons can often be made with a smaller uncertainty than is achieved in the best calibrated “absolute ” (=SI-traceable) atomic-weight determinations. Accurate determinations of the atomic weights of certain elements also influence the values of fundamental constants such as the Avogadro, Faraday, and universal gas constants. This review is in two parts: the first summarizes the development of the science of atomic-weight determinations during the 20th century; the second summarizes the changes and variations that have been recognized in the values and uncertainties of atomic weights, on an element-by-element basis, in the latter part of the 20th century.

Aqueous alteration is one of the primitive activities that occurred on meteorite parent bodies in the early solar system. The Tagish Lake meteorite is known to show an intense parent body aqueous alteration signature. In this study, quantitative analyses of the alkaline elements and isotopic analyses of Sr and Ba from acid leachates of TL (C2-ungrouped) were performed to investigate effects of aqueous alteration. The main purpose of this study is to search for isotopic evidence of extinct 135Cs from the Ba isotopic analyses in the chemical separates from the Tagish Lake meteorite. Barium isotopic data from the leachates show variable 135Ba isotopic anomalies (e = −2.6 ~ +3.6) which correlatewith 137Ba and 138Ba suggesting a heterogeneous distribution of s- and r-rich nucleosynthetic components in the early solar system. The 87Rb–87Sr and 135Cs–135Ba decay systems on TL in this study do not provide any chronological information. The disturbance of the TL chronometers is likely a reflection of the selective dissolution of Cs and Rb given the relatively higher mobility of Cs and Rb compared to Ba and Sr, respectively, during fluid mineral interactions.

Sensitive high resolution ion microprobe (SHRIMP) U–Pb analyses of zircons from a pelitic gneiss clast from the Jurassic Kamiaso conglomerate in central Japan show that most grains are 1850–1950 Ma, but six are >2400 Ma, including a very old one (>3254±14 Ma). The SHRIMP data give chronological evidence for previously unrecognized igneous activity from 1850 to 1950 Ma. The existence of Archean zircons allows us to consider the evolutionary history of the Archean crust in eastern Asia. Chondrite-normalized REE patterns of the individual zircons determined by SHRIMP show that the 2400–3250 Ma zircons have large positive Ce and small negative Eu anomalies, whereas the 1850–1950 Ma zircons have small positive Ce and significantly negative Eu anomalies. These differences in the REE abundances for the 2400–3250 and 1850–1950 Ma zircons may reflect the composition of the melt that produced the zircons, and reveal the possibility of a geological constraint on the origin of Kamiaso zircons.

It is known that most lunar meteorites have complicated cosmic-ray exposure experiences on the Moon and in space. In this study, cosmic-ray irradiation histories of six lunar meteorites, Dhofar 489, Northwest Africa 032 (NWA 032), NWA 479, NWA 482, NWA 2995, and NWA 5000, were characterized from neutron-captured isotopic shifts of Sm and Gd, and from the abundances of long-lived cosmogenic radionuclides like 10Be, 26Al, 36Cl, and 41Ca. Sm and Gd isotopic data of all of six meteorites show significant isotopic shifts of 149Sm–150Sm and 157Gd–158Gd caused by accumulation of neutron capture reactions due to cosmic-ray irradiation, corresponding to the neutron fluences of (1.3–9.6) × 1016 n cm−2. In particular, very large Sm and Gd isotopic shifts of NWA 482 are over those of a lunar regolith 70002, having the largest isotopic shifts among the Apollo regolith samples, corresponding to cosmic-ray exposure duration over 800 million years in the lunar surface (2π irradiation). Meanwhile, the concentrations of cosmogenic radionuclides for individual six meteorites show the short irradiation time less than one million years as their bodies in space (4π irradiation). Our data also support the results of previous studies, revealing that most of lunar meteorites have long exposure ages at shallow depths on the Moon and short transit times from the Moon to the Earth.

A variant in a transcription factor gene, POU4F3, is responsible for autosomal dominant nonsyndromic hereditary hearing loss, DFNA15. To date, 14 variants, including a whole deletion of POU4F3, have been reported to cause HL in various ethnic groups. In the present study, genetic screening for POU4F3 variants was carried out for a large series of Japanese hearing loss (HL) patients to clarify the prevalence and clinical characteristics of DFNA15 in the Japanese population. Massively parallel DNA sequencing of 68 target candidate genes was utilized in 2,549 unrelated Japanese HL patients (probands) to identify genomic variations responsible for HL. The detailed clinical features in patients with POU4F3 variants were collected from medical charts and analyzed. Novel 12 POU4F3 likely pathogenic variants (six missense variants, three frameshift variants, and three nonsense variants) were successfully identified in 15 probands (2.5%) among 602 families exhibiting autosomal dominant HL, whereas no variants were detected in the other 1,947 probands with autosomal recessive or inheritance pattern unknown HL. To obtain the audiovestibular configuration of the patients harboring POU4F3 variants, we collected audiograms and vestibular symptoms of the probands and their affected family members. Audiovestibular phenotypes in a total of 24 individuals from the 15 families possessing variants were characterized by progressive HL, with a large variation in the onset age and severity with or without vestibular symptoms observed. Pure-tone audiograms indicated the most prevalent configuration as mid-frequency HL type followed by high-frequency HL type, with asymmetry observed in approximately 20% of affected individuals. Analysis of the relationship between age and pure-tone average suggested that individuals with truncating variants showed earlier onset and slower progression of HL than did those with non-truncating variants. The present study showed that variants in POU4F3 were a common cause of autosomal dominant HL.

This paper presents a wearable assistance system for service and maintenance personnel in industrial facilities, when used together with mobile smart devices. It provides a practical interaction metaphor designed to fully utilize the user's physical activities, such as touch and hand gestures. As a result of a user activity-driven design approach, the presented system frees user from various constraints during various working operations. Especially, our new developed gesture input method enables the user to immediately interact with services using one-handed motions in an arbitrary postures. Furthermore, an event-driven architecture is proposed to solve the power management problem. We also developed a wristwatch-like wearable device to evaluate the effectiveness of the proposed method. The results presented in this paper demonstrate that the proposed system not only allows for effective and satisfactory service but also cuts down on errors and oversights. Finally, potential applications of this research that include design guidelines for future interface

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 ...

Acute rhinosinusitis is frequently associated with secondary orbital infection, most commonly subperiosteal abscess. Although orbital subperiosteal abscess is a deadly disease that might lead to blind and cavernous sinus thrombosis, recent review of literature showed that immediate surgical intervention might not always be necessary for subperiosteal abscess. Orbital inflammation secondary to sinusitis is common in children, whereas orbital subperiosteal hematoma secondary to sinusitis is extremely rare, with only 11 reported cases, including one case in children. All the cases were treated with surgical intervention. Here we present a 12-year-old girl with rhinosinusitis and proptosis. Emergent endoscopic sinus surgery with partial removal of the lamina papyracea revealed dark brown fluid in the subperiosteal space. The patient was symptom-free 2 weeks after surgery. The present case was treated exclusively via an endonasal approach, whereas all 11 previous cases of subperiosteal hematoma were treated with external incision. The endonasal approach is favorable, especially for young female patients. Our review of literature shows that sudden onset, afebrile, and few signs of inflammation on blood test in patients with subperiosteal lesion may indicate subperiosteal hematoma. Surgery rather than antibiotic administration should be considered for the treatment of suspected subperiosteal hematoma. Treatment through only the endonasal approach is possible even if the hematoma is located in the roof of the orbit.

Streptococcus (S.) pyogenes is well recognized as the most common pathogen causing pharyngotonsillitis in school-age children. In Japan, mucoid Streptococcus pneumoniae is well known as a causative agent of severe acute otitis media (AOM); however, mucoid S. pyogenes has rarely been reported. To the best of our knowledge, this is the first report of an AOM patient caused by mucoid S. pyogenes in Japan. A 36-year-old previously healthy female was referred to our hospital with suspicion of cerebrospinal otorrhea due to increasing otalgia accompanied by headache following myringotomy. Bacterial cultures of middle ear secretions were performed, and mucoid-form colonies surrounded by zones of complete β-hemolysis were produced on sheep's blood agar. Antigen-agglutination test results were positive for S. pyogenes, and thus the patient received treatment with panipenem-betamipron 2.0 g/day for 10 days, which resolved nearly all symptoms. The bacteriological features of this strain were then investigated. The M-protein genotype encoded by the emm gene, the major virulence factor of S. pyogenes, was determined to be emm75. Generally, S. pyogenes forms colonies having non-mucoid matt appearances based on β-hemolysis of sheep's blood agar. The mucoid phenotype results from abundant production of hyaluronic acid capsular polysaccharide, a key virulence determinant. emm75 is common in noninvasive, but less common in invasive disease. In conclusion, mucoid S. pyogenes can cause severe infection even in previously healthy persons. Emergence of mucoid S. pyogenes and drug resistance trends should be monitored in the future.

Objective: The object was to describe 2 novel cases of peritonsillar abscess showing peculiar extension to the masticator space. Methods: The methods included clinical case records, including computed tomography and surgical approaches. Results: Both patients we encountered were suffering from systematic diseases, with case 1 involving a 75-year-old man with diabetes mellitus and case 2 involving a 90-year-old woman taking immunosuppressive medications. The abscesses were peritonsillar in origin, extending primarily to the parapharyngeal space, with unusual secondary extension to the masticator space. Extraoral drainage conducted in case 1 was useful for assessing the masticator space and surrounding spaces, but endoscopy-assisted intraoral drainage in case 2 was less invasive, obviating the need for identifying the facial nerve. Conclusions: It is important to bear in mind that patients suffering from systemic diseases may display unusual extension of deep head and neck infections, and enhanced computed tomography is a useful modality for evaluating such extensions.

Here we report the isotopic excess of 135 Ba studied from Ba isotopic measurements of acid leachates of Allende calcium–aluminum rich inclusions (CAIs) and two primitive chondrites, Beardsley (H5) and Zag (H6 clasts). From the excess 135 Ba abundances of CAIs, after subtraction of the r-process nucleosynthetic component in a model-dependent manner, a value for 135 Cs/ 133 Cs=(4.8±0.8)×10 −4 is proposed as the initial ratio in the early solar system. A correlation between excess 135 Ba abundances and Cs/Ba ratios observed in the Beardsley and the Zag meteorites reveals the possible existence of primordial 135 Cs in the two meteorite parent bodies. On the assumption of two cases for 135 Cs/ 133 Cs initial in the early solar system, the 135 Cs– 135 Ba isochron suggests that primitive (aqueous) alteration in the Beardsley and Zag meteorite bodies occurred at 8.2∼11.9 Ma and 13.9∼17.6 Ma after CAI formation, respectively. Our results are apparently consistent with previously reported data from Pb–Pb model age determinations, and 53 Mn– 53 Cr chronometry for chondrites. This is the first report of isotopic excess of 135 Ba in meteorites, which may relate to live 135 Cs in the early solar system and the 135 Cs– 135 Ba chronological application.

Isotopic analyses of Sm and Gd in 10 uranium minerals with different formation ages were performed by thermal ionization mass spectrometry to investigate neutron capture effects due to spontaneous fission-released neutrons. The results from some uraninites show significant isotopic shifts on 150Sm/149Sm and 158Gd/157Gd due to neutron capture. Uraninites with high U contents, low Sm/U and Gd/U ratios, and geologically old ages (older than 1.5 Ga) have isotopic characteristic pointing to the occurrence of neutron capture reactions. Estimation of neutron fluences and differences of neutron energy spectrum in individual U ores are discussed from the isotopic data. The Shinkolobwe (Zaire) uraninite has especially clear isotopic deviations of Sm (e149Sm = −2.5, e150Sm = +3.7) and Gd (e157Gd = −2.3, e158Gd = +2.0), and its isotopic shifts correspond to a neutron fluence of 2.0 × 1015 n/cm2. The combination of isotopic data from Sm and Gd implies that fission-released neutrons of the Shinkolobwe sample are not well-thermalized relative to those of other uraninites. The Oklo sample taken from out of the natural fission reactor shows a fluence of 2.6 × 1016 n/cm2, which is 1.38 times higher than expected from other uraninites with the same formation age. Furthermore, it contains not only neutron capture products but also 2.9% of fissiogenic Sm relative to total Sm. This suggests that fission chain reactions began in this Oklo sample, but that criticality could never be sustained. There is a correlation between total rare earth element content and neutron fluxes in uraninites. As one of the geochemical characteristics, total rare earth element content in the Oklo sample is much lower than those in other uraninites. This suggests that rare earth elements in uraninites work as neutron absorbers, thereby preventing the fission process from reaching the critical point of a self-sustaining chain reaction.

Large-scale light rare earth element (LREE), uranium, lead and phosphorus migration has been evidenced in the FA Lower Proterozoic sandstones of the Franceville basin (Gabon) hosting Oklo natural nuclear reaction zones (RZ) in relation with extensive accessory mineral alteration by highly saline diagenetic brines (28.7 wt.% NaCl eq. to 30 wt.% CaCl2 eq.) at about 140°C and 1 kbar. Monazite is the most severely altered accessory mineral in the coarse-grained sandstones of the basal FA formation. Detrital monazite crystals are altered to Th–OH silicate microcrystalline phase with very low concentrations of U and LREE. The Th/La ratio increase from non-altered (Th/La∼0.27) to altered sandstones (Th/La∼1.14) shows that about 76% of the LREE was leached. This corresponds to the leaching of 2.01×109 metric tons at the scale of the FA formation in the Franceville basin. Similarly, the Th/U increase from monazite (Th/U=18.6) to the Th-silicate phase (Th/U=88.7) is interpreted as a result of an alteration by oxidizing brines with leaching of U together with LREE and P. It corresponds to the leaching of 9.06×106 metric tons of uranium. This amount of uranium largely exceeds the known uranium reserves from the Franceville basin. In zircon crystals, the cores are generally homogeneous, weakly fractured and well preserved as attested by the Archean ages (2867±24 and 2865±51 Ma) obtained by ionic microprobe analysis on zircon of the FA Formation, respectively, from the marginal and central parts of the basin. Their composition corresponds to the pure end-member (Zr,Hf)(SiO4), poor in Th and U (Th/U∼1). At the contrary, their rims, which present several growth zones with cracks fillings, are enriched in REE, P, Th and U with higher Th/U ratios (5–10). Both altered monazite and altered zircon contain galena as numerous inclusions in the outer growth zones and as crack fillings. For example, in zircon, the Pb of galena crystals (3–23 wt.%) largely exceeds the amount of Pb (maximum 0.1 wt.%) that would have been produced in situ by radioactive decay in this mineral. Nearly all the lead were introduced into altered zones of accessories. Dissolution of accessory minerals occurred at 2000 Ma, producing a porous and distorted crystal structure which has allowed a later incorporation of Pb. Galena inclusions in altered zircons located in the vicinity of reactor zones have radiogenic lead compositions. Altered zircon rims and galena inclusions in altered zircon located far from reactor zones have non-radiogenic Pb isotopic compositions, confirming the external origin of lead. Pb isotopic evolution models indicate a crystallization age sometime after 1000 Ma, both for galena located close to and far from U mineralizations and reactor zones, which may be synchronous with a regional extension event contemporaneous with intrusion of dolerite dyke swarms, between 1000 and 750 Ma, at the scale of the Franceville basin. The present study also illustrates the different retention capacities of accessory mineral for elements representing analogs of the radiotoxic nuclides in the relatively extreme natural conditions created by the circulation of moderately hot and chloride-rich fluids during the diagenesis of a sedimentary basin.

Isotopic compositions of Sm and Gd in eight chondrites (Mezo-Madaras, Parnallee, Otis, Suizhou, Zhaodong, Allende, Bruderheim and Y-74191) were measured to study neutron capture effects due to the interaction of cosmic rays with planetary materials in space. The anti-correlation of 149Sm/152Sm with 150Sm/152Sm and of 157Gd/160Gd with 158Gd/160Gd in the meteorites provides evidence for neutron capture effects in these chondrites. Isotopic deviations observed in the eight chondrites are ϵ149Sm=−0.35 to −1.93, ϵ150Sm=+0.87 to +4.35, ϵ157Gd=−2.82 to −1.21 and ϵ158Gd=+0.33 to +1.66, which correspond to thermal neutron fluences of (1.03–5.17)×1015 n cm−2. The combination of isotopic data from Sm–Gd in this study and Ne–Kr from the literature provides information on the secondary produced thermal ( 5 MeV) neutron fluences for chondrites, and it is used here to estimate the neutron energy distribution for six L- and LL-chondrites. From the difference of distribution of thermal, epi-thermal and fast neutron fluences in individual chondrites, the depth of the samples inside the meteoroid is discussed. In Allende, the isotopic anomalies observed may be due not only to neutron capture reactions but also to additions of r-process nuclides of Sm and Gd.

Elemental abundances and isotopic compositions of rare earth elements (REE), Th and U of twenty eight samples from four kinds of natural fission reactors at the Oklo and Bangombe uranium ores were determined by mass spectrometry. Fissiogenic and non-fissiogenic REE components of each sample were calculated from the isotopic compositions. The geochemical distribution of both fissiogenic and non-fissiogenic REE differs among the four reactors. Each reactor shows the following features possibly associated with the local geochemical conditions. (1) Reactor 9 at the shallow depth of the Oklo deposit contains higher amounts of non-fissiogenic REE than the other reactors. The distribution of non-fissiogenic REE does not reflect the primordial REE abundance patterns, and might have been disturbed in and around the reactor due to supergene alteration. Our results suggest that significant amounts of fissiogenic lighter REE (LREE), such as La, Ce and Pr, were mobile in the reactor; (2) Reactors 10 and 13 located deep underground have much lower contents of non-fissiogenic REE than reactor 9. All fissiogenic REE show high retention in the reactors. Non-fissiogenic REE of reactor 10 inform of the primordial ore formation without any geochemical disturbance. Little redistribution of both fissiogenic and non-fissiogenic REE in the reactor 10 was observed; and (3) The Bangombe reactor located at shallow depth has apparently well preserved fissiogenic REE. Non-fissiogenic REE in the Bangombe reactor might have been disturbed, possibly by hydrothermal processes. The distribution behavior of fissiogenic REE is considered to be related with physico-chemical reactor conditions such as nuclear reaction temperature and chemical compositions of each reactor, but clear relationship between nuclear parameters and the REE distribution could not be obtained in this study.

— 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.

The effects of the addition of contralateral noise on the psychophysical tuning curve (PTC) were examined in subjects with normal hearing. The masking threshold of the tail part of the PTC tended to decrease with the addition of contralateral noise, although the threshold reduction was usually less than 5 dB. On the other hand, the effects of contralateral noise were relatively small around the tip of the PTC contour. Focusing on the effects of contralateral noise on the masking threshold at the tail part of the PTC, the effects of changing the time between initiation of masking the tone and the presentation of the masked probe tone on the threshold reduction at the tail part of the PTC were also observed. The results indicate that the reduction of the masking threshold by the addition of contralateral noise tended to be larger when the presentation of the signal tone was delayed after the onset of the masker. Usually, when the signal tone was presented under conditions of the forward masking paradigm, the reduction of the threshold was most remarkable. Results obtained in the present study are discussed based on the known characteristics of the olivocochlear (OC)-efferent fibers activated by contralateral noise.

We have measured U concentrations, and elemental ratio of 238 U/ 206 Pb, and isotopic compositions of Pb in thirteen zircons extracted from a volcaniclastic rock of the Kamiaso conglomerate in the Mino terrane and sixty three analyses in fifty zircons from the Amo gneiss, a metamorphic rock originated from an intermediate volcanic rock in the Hida terrane of central Japan by means of an ion microprobe. Zircons from the Kamiaso were first analyzed in Australian National University (ANU) and then measured again by Hiroshima University (HU) Sensitive High Resolution Ion MicroProbe. Both radiometric ages of 238 U/ 206 Pb* and 207 Pb*/ 206 Pb* obtained by the ANU instrument agree well with those by HU except for one sample. There are six geochronological episodes in the Kamiaso sample; about 2550 Ma, 2000 Ma, 1300 Ma, 920 Ma, 250 and 220 Ma. U-Pb zircon geochronology of the Amo sample indicates that there are six concordant zircon episodes and three concordia intercept episodes; about 3420 Ma, 2560 Ma, 1840 Ma, 1130 Ma, 580 Ma, 400 Ma, 360 Ma, 285 Ma, and 250 Ma. The 3420 Ma is the oldest age so far reported in Japan. The 2560 Ma event may have a relation to the period of the evolution of the Sino-Korean craton between 2.7‐2.5 Ga. The third age peak of about 1840 Ma suggests that the zircons were derived from the Ryongnam massif in South Korea with the similar formation age. The younger ages of 1130 Ma, 580 Ma, 400 Ma, 360 Ma and 285 Ma may be minor events recorded in the Hida metamorphic belt. The latest age of 250 Ma may be the most important metamorphic event in Hida terrane. Rare earth element abundance patterns of the Amo zircons show progressive increase with atomic number together with positive Ce anomaly, which is a typical zircon signature. Small negative anomaly of Eu is found in zircons with the age of 2560 Ma and 250 Ma while zircons with intermediate ages show large anomaly. There is no correlation between Ce and Eu anomaly, suggesting that both anomalies may not have been simply controlled by the oxidation state during zircon crystallization.

Large isotopic deviations of 149Sm–150Sm and 157Gd–158Gd derived from neutron capture effects were observed in five enstatite achondrites (aubrites); Norton County, ALH78113, Cumberland Falls, Bishopville and Mayo Belwa. The isotopic variations of these aubrites (e149Sm = −32 to minus7, e150Sm = +11 to +57, 8157Gd = –42 to –14 and e158Gd = +9 to +26) correspond to irradiation with neutron fluence of (1.17 – 3.99) × 1016 n cm−2, which is within the range of estimated neutron fluence values of some lunar samples. These results indicate that aubrites may have been located near the surface of their parent body for several hundreds of Ma. Furthermore, the neutron energy spectrum obtained from the combination of Sm and Gd isotope systematics (eSm/eGd) suggests that the energy of thermalized neutrons in five aubrites was in the range of 200–400 K, and was lower than those in lunar samples A-12 and A-15. In addition, we analyzed one anomalous aubrite (Mt. Egerton), and two enstatite chondrites (Happy Canyon and Abee) to investigate the relationship of their origin with aubrites. However, these three meteorites showed no evidence for intensive neutron irradiation observed in the aubrites.

Objective: The Jet Stream Olfactometer, a modification by the T&T olfactometer, has been recently developed and is now commercially available. This Jet Stream Olfactometer can routinely measure the unilateral sense of smell. Clinical usefulness of the Jet Stream Olfactometer was evaluated. Methods: Twenty-three patients with sinus-related symptoms were examined. Unilateral olfactory acuity was examined using the Jet Stream Olfactometer and compared it with the anatomy of the olfactory cleft by computed tomographic (CT) scans. Results: In 13 of the 23 patients examined the right olfactory threshold was similar to that of the left. Of these 13, in seven patients there was transport damage of the odorants and in the other six there was sensorineural damage. Ten patients showed an apparent difference between the right and left smell thresholds. Anosmia in seven of these ten patients was due to a conductive olfactory disturbance resulting from rhinosinusitis, whereas sensorineural damage was recognized in the other three patients. The difference in the detection threshold between the right and left nasal cavities was well correlated to that of the opacity between the right and left olfactory clefts. Conclusion: Jet Stream Olfactometer provides a convenient and reliable means for assessing the ability of unilateral smell.

U-Pb isotopes of apatites and zircons extracted from a sample of the Acasta gneisses that occurs along the western margin of the Slave craton in Northwest Territories of Canada have been measured using a SHRIMP II ion microprobe. Eleven apatite analyses (30 μm spot) give 238U/204Pb-206Pb/204Pb and 204Pb/206Pb-207Pb/206Pb isochron ages of 1905 ± 86 Ma (2 σ) and 1936 ± 28 Ma (2 σ), respectively. Analyses (20 μm spot) on the partly recrystallised central portions of fourteen zircons mostly define a mixing array on a 238U/206Pb∗-207Pb∗/206Pb∗ concordia plot with concordia intercepts at 4014 ± 25 Ma (2 σ) and 1967 ± 93 Ma (2 σ). The former agrees with 3.96–4.02 Ga protolith ages obtained on the oldest components of the Acasta gneisses by other workers. The lower concordia intercept for the zircon data is consistent with the U-Pb age of apatites and may be related to a >500°C thermal event, perhaps early in the Palaeoproterozoic Wopmay orogeny.

Ruthenium isotopic compositions of eleven samples selected from four kinds of natural fission reactors at Oklo and Bangombe uranium deposits were determined by inductively coupled plasma mass spectrometry (ICP-MS). The detectable Ru isotopes in all samples were only fissiogenic origin. The fission contribution of 235 U , 238 U and 239 Pu in each reactor was estimated by using 102 Ru / 101 Ru and 104 Ru / 101 Ru isotopic ratios. Some of the samples show unusual Ru isotopic compositions, possibly derived from fast neutron induced fission. Depletion or enrichment of isotopic abundance of fissiogenic 99 Ru , defined as Δ 99 Ru , reveals the occurrence of a chemical fractionation between Ru and Tc in the reactors. A major part of the fissiogenic Ru has been incorporated into micro metallic aggregates containing Ru, Rh, Te, Pb, As and S in the reactors. In situ analyses of metallic aggregates by secondary ion mass spectrometry (SIMS) and electron probe micro analysis (EPMA) were performed to obtain information on formation process of the aggregates. A correlation between Δ 99 Ru and isotopic abundance of 100 Ru was observed in the metallic aggregates. This correlation suggests that the chemical fractionation between Tc and Ru in the reactors had occurred at the first stage of criticality, and that 100 Ru was produced by successive neutron capture during criticality. The chemical compositions indicate that the aggregates were formed as a mixture of PbS and fissiogenic Ru–Rh–Te components.

Sound localization in subjects with chronic otitis media (COM) was examined before and soon after ear surgery by means of virtual sound presented by headphones, sound being synthesized based on the head-related transfer functions (HRTFs) in a normal subject. The localization ability in COM patients was usually worse than that in normal subjects, but was better than expected when compared with cases of acute loss. On the other hand, the effects of hearing improvement on localization ability observed in COM patients were smaller than those of simulated acute hearing loss achieved by earplugs in normal subjects. This seems to suggest that the localization cues in patients with chronic hearing loss are different from those under normal conditions.

The Oklo and Bangombe uranium ores in the Republic of Gabon are fossils of natural fission reactors. Many elements in these natural fission reactors show isotopic anomalies derived from fission and neutron capture reactions. Isotopic analyses of uraninites and some other minerals provide useful information on the geochemical behavior of fission products and nuclear chemical characterization of the reactors. Integrated isotopic measurements by whole rock analysis with inductively coupled plasma mass spectrometry (ICP-MS) and thermal ionization mass spectrometry (TIMS) and by in-situ analysis with secondary ion mass spectrometry (SIMS) make it possible to clarify the migration processes of fissiogenic nuclides over a range of scales from micro meters to meters.

To illustrate in situ Sensitive High Resolution Ion MicroProbe (SHRIMP) analysis of apatites, Pb isotopes and Pb/U ratios of five apatite samples with different ages have been measured using SHRIMP II ion microprobe at Hiroshima University. The `PRAP' apatite from a carbonatite complex at Prairie Lake, Ontario with a 207 Pb ∗– 206 Pb ∗ age of 1156±45 Ma (2 σ) was used as the standard for 206 Pb + / 238 U + – 238 U 16 O + / 238 U + calibration. Apatites from the Poohbah Lake alkaline complex give 204 Pb / 206 Pb – 238 U / 206 Pb and 204 Pb / 206 Pb – 207 Pb / 206 Pb isochron ages of 2726±145 Ma (2 σ) and 2701±86 Ma (2 σ), in agreement with a conventional TIMS 207 Pb ∗– 206 Pb ∗ age of 2667±10 Ma (2 σ) and a K–Ar isochron age of 2706±46 Ma (2 σ). For the remaining three apatite samples the 204 Pb / 206 Pb – 238 U / 206 Pb and 204 Pb / 206 Pb – 207 Pb / 206 Pb isochron ages obtained by SHRIMP are consistent with radiometric and geological ages in the literature.

The relationship between the acoustic reflex threshold (ART) and loudness was examined in patients with unilateral hearing losses and subjects with simulated hearing losses using a masking method. Significant differences in the ART between the two ears of patients with unilateral hearing losses were correlated with differences in loudness at the level of the ART with differences in loudness determined by the alternate binaural loudness balance test. A similar relationship of ART and the sensation of loudness was also observed in ears with simulated hearing losses. The results obtained in the present study suggest a positive relationship between the ART and loudness, and provide some support for the assumption that a common neuronal information pathway plays an important role both in producing the loudness and eliciting the acoustic reflex.

Isotopic studies have been completed on samples from the natural fission reactors at Oklo and Bangombe in order to determine the conditions under which they functioned when critical and to evaluate the retention and migration of fissiogenic radionuclides. The abundances and isotopic compositions of the elements Rb, Sr, Zr, Ru, Pd, Ag, Te, Ba, rare earth elements (REEs), and U have been measured by thermal ionization mass spectrometry (TIMS) and inductively coupled plasma mass spectrometry (ICP-MS). Isotopic analyses and in situ ion imaging have also been performed by using an ion microprobe. Seven samples were taken from the SF84 borehole (zone 10), one from the S2 borehole in gallery SD37 (zone 13), both being zones in the Oklo deposit, and one from the BA145 borehole in the Bangombe deposit. The isotopic data allow for a detailed description of the functional conditions of these reactors, and based on these results, we have calculated the retention rates of the fissiogenic nuclides and nucleogenic Bi and Th. The nuclear parameters of the natural fission reactors are characterized by the isotopic abundances of Ru, Nd, Sm, Gd, Er, Yb, Lu, and U: neutron fluence (n/cm2), fission proportions of 235U, 238U, and 239Pu, the restitution factor of 235U resulting from 239Pu decay, average temperature (°C) in the reactor, and duration of functioning (yr). In the 70 cm thick reactor core encountered by borehole SF84, the neutron fluence is in the range from 5.3x1020 to 8.0x1020 (n/cm2). The variation in 235U depletion shows a strong positive correlation with the restitution factor and an inverse correlation with neutron fluence, which demonstrates the stability of the reaction zone since the period of criticality. Large depletions of 149Sm, 155Gd, and 157Gd have been detected in a sample of sandstone from 60 cm below this reactor core which also had a normal uranium isotopic ratio (235U/238U = 0.007254); this resulted from neutron capture reactions. The neutron fluence calculated from these isotopic anomalies is relatively high (6.2x1018 n/cm2) and probably shows that nuclear reactions began, but that criticality could never be sustained due to an excess of neutron poisons (e.g., Sm and Gd). The results obtained from SD37 reveal that reactor zone 13 is not similar to the other reactor zones. The proportion of 238U fission as calculated from the isotopic composition of Ru is extremely high (18% of the total), while that of SF84 (zone 10) is at most 5.0% of total fission. This result implies that the duration of criticality in reactor zone 13 was much shorter than in other reactor zones. In the Bangombe reactor zone BA145, the chemical and nuclear characteristics are close to those of SF84. The retentivities of many fission products as compared with fissiogenic Nd have been assessed for the reactor core samples. From the measured and calculated relative retentions, more than 90% of fissiogenic Ru, Rh, Pd, Te, and REEs have been retained in SF84 and SD37. In these same zones, however, the relative retentions of fissiogenic alkaline and alkaline earth elements are less than 20%. The retentions of long-lived radioisotopes, such as 90Sr, 99Tc, 137Cs, 236U, and 237Np have been calculated by reference to their radiogenic daughters 90Zr, 99Ru, 137Ba, 232Th, and 209Bi, respectively. The excess or depletion of isotopic abundances measured in the daughter nuclides has allowed the prediction of the rate of chemical fractionation between the parent and daughter nuclides in the reactor during criticality. These results greatly improve the understanding of the Oklo phenomenon and provide important data for the evaluation of the concept of long-term storage of radioactive wastes in geological formations.

A new portable digital hearing aid referred to as CLAIDHA (Compensate for Loudness by Analyzing Input-signal Digital Hearing Aid), which employs frequency-dependent amplitude compression based on narrow-band loudness compensation, was clinically evaluated in 159 subjects with hearing loss. The results of speech tests revealed better intelligibility compared with the subject's own hearing aids; the advantage of using CLAIDHA in daily life was also indicated by the results of a questionnaire completed by the subjects. In about 64% of the subjects with a flat, gradually sloping type of hearing loss, CLAIDHA was satisfactorily adopted for daily use. However, in the subjects with a steeply sloping type of hearing loss and subjects with losses mainly at high and low frequencies, with near-normal mid-frequency hearing. this loudness compensation scheme seems to be slightly less effective.

Objective Preservation of residual hearing during cochlear implantation is important. This study investigated changes in endocochlear potential (EP) during simulated cochlear implant (CI) electrode insertion. Study design Laboratory animal study. Setting Academic hospital laboratory. Subjects and methods Guinea pigs were divided into 4 groups: cochleostomy only (4 animals), suction after cochleostomy (5 animals), simulated CI electrode insertion parallel to the longitudinal axis of the scala tympani without suctioning (7 animals), and simulated CI electrode insertion toward the modiolus without suctioning (7 animals). The EP was measured from the second turn of the cochlea, and the values after 20 minutes were compared. Results The EP showed little change at 20 minutes after cochleostomy with a nearly normal value of 84.83 ± 2.12 mV. Suctioning of the perilymph from the cochleostomy site caused a slight acute reduction in EP by about 6 mV, and the value at 20 minutes after cochleostomy was 78.64 ± 4.42 mV. Insertion of the simulated CI electrode parallel to the longitudinal axis of the scala tympani caused a slight decrease in EP to 78.91 ± 5.06 mV. Insertion toward the modiolus caused a marked decrease in EP to 54.13 ± 4.42 mV at 20 minutes after the treatment, significantly lower compared with the other 3 groups. Conclusion EP was well preserved during carefully performed surgical procedures of simulated CI electrode insertion, but it decreased significantly if the simulated CI electrode was inserted toward the modiolus. Careful attention is necessary to ensure the correct direction of CI electrode insertion to preserve residual hearing. Use of suction should be minimized if possible.

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.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.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).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.