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Dust is one of primary sources of new elements to oceanic water, but understanding of their dissolution behavior is still elusive1. Here we report evidence showing that diatoms are actively associated with the dissolution of silicate minerals. The cultivation of three diatom species was carried out with and without feldspar particles, albite and bytownite. Following cultivation, the girdles of Coscinodiscus frustules showed double Si peaks and the outer layers of the girdles showed significantly higher Al/Si ratios than the inner layers when feldspar particles were present. Feldspar particles showed rounded or fractured edges following the cultivation, which are not seen in the absence of diatoms. With presence of feldspar particles, significantly greater amounts of transparent exopolymer particles (TEP) were secreted after silicic acid concentration dropped almost to zero. A micro-fluorescence study revealed that the diatom cells actively lowered pH to keep the environment favorable to mineral dissolution by TEP. It is concluded that diatoms secrete TEP to digest feldspar and utilize silica, under conditions of silicic acid deficiency. The impurity of frustules is the reflection of such physiological activities. This finding reveals the presence of a previously unknown, yet important passage for elements to enter the oceanic system.

The Hayabusa2 spacecraft succeeded in sampling and returning asteroidal materials from the C-type near-Earth asteroid (162173) Ryugu. As part of the Hayabusa2 Initial Analyses, chemical compositions and isotopic ratios of volatile species were measured. The samples analyzed were grains about 1mm in diameter and were individually treated without exposure to Earth’s atmosphere through the entire processes to minimize alteration and contamination effects by adsorption of Earth’s atmosphere and chemical reactions with reactive species such as oxygen and water contained in the atmosphere. In order to perform spectroscopic and electron-microscopic observations in advance of a series of the isotope measurements, the sample surface must be smoothed. We employed a pelletization method to obtain the flatness for the valuable return samples because the pelletization is a less sample-consuming method compared to mechanical/electron polishing, microtome, and ion milling. The pelletization does not only provided a smooth surface, but also contributed to easier handling of small (less than about 1 mm in diameter) samples. In order to perform the subsequent analyses, the samples must be minimally contaminated during the pelletization procedure and be easy to remove from the pelletization tools. Therefore, embedding in resins or low-melting-point metals cannot be used. Under these constraints, the tools and methods for sample pelletization, handling, and transportation were developed. We describe the methods and the tools that enable to treat pristine asteroidal samples under non-atmospheric exposure condition throughout transportation, weighing, pelletization, and installation to the instruments for chemical and isotope measurements. Our methods and tools can be applied to other small samples including meteorites, cosmic dust, and the future return samples.

Bioleaching of arsenic (As)-rich, so-called “dirty” concentrates can produce additional Cu value from the flotation waste while simultaneously releasing toxic As. This study bioleached three such concentrates of varying pyrite/enargite ratios ([Py]/[Ena] = 0.7, 1.3 and 2.4) at a pulp density of 20%. The dissolution behavior of Cu and As in relation to the solution redox potential (Eh) was studied with and without activated carbon (AC) as a potential Eh-controlling catalyst. At this high pulp density, Eh was naturally suppressed, without a need for AC dosing, to

CASA, the Common Astronomy Software Applications, is the primary data processing software for the Atacama Large Millimeter/submillimeter Array (ALMA) and the Karl G. Jansky Very Large Array (VLA), and is frequently used also for other radio telescopes. The CASA software can handle data from single-dish, aperture-synthesis, and Very Long Baseline Interferometery (VLBI) telescopes. One of its core functionalities is to support the calibration and imaging pipelines for ALMA, VLA, VLA Sky Survey (VLASS), and the Nobeyama 45m telescope. This paper presents a high-level overview of the basic structure of the CASA software, as well as procedures for calibrating and imaging astronomical radio data in CASA. CASA is being developed by an international consortium of scientists and software engineers based at the National Radio Astronomical Observatory (NRAO), the European Southern Observatory (ESO), the National Astronomical Observatory of Japan (NAOJ), and the Joint Institute for VLBI European Research Infrastructure Consortium (JIV-ERIC), under the guidance of NRAO., Comment: Accepted for publication in PASP (20 pages, 4 figures). Joint publication with CASA-VLBI paper

We measured the oxygen and hydrogen isotope ratios of smectite, chlorite, and illite in hydrothermally active sediments at the Iheya North Knoll, Okinawa Trough, obtained by seafloor drilling of active hydrothermal fields during the Integrated Ocean Drilling Program (IODP) Expedition 331. Formation temperatures calculated from oxygen isotope data were compared to the downhole temperatures that were measured during the same expedition. The δ18O values ranged from +9.9‰ to +13.3‰ for smectite, +1.3 to +3.0‰ for chlorite or chlorite/smectite mixed-layer mineral, and +2.1‰ to +5.1‰ for illite or illite/smectite mixed-layer mineral with minor chlorite. For samples of illite that contained minor chlorite, δ18O values for illite or illite/smectite mixed-layer mineral of +4.4‰ to +6.1‰ were calculated, based on the proportion of the two clay minerals calculated from chemical composition of the individual mineral and the mixture determined by TEM-EDS and EPMA. We estimated the formation temperatures of the minerals using oxygen isotope fractionation data and assumed values of 0 to +1.2‰ for the fluid that was equilibrated with the minerals, based on the reported values of the seawater and vent fluid measured in previous studies. The temperature range calculated was 111–175 °C for a shallow layer less than about 25 m below seafloor (mbsf) that contained smectite and a minor kaolinite component, 177–297 °C for a deeper layer between about 25 and 40 mbsf that was dominated by chlorite or chlorite/smectite mixed-layer mineral, and 220–314 °C for the deepest layer between about 40 and 120 mbsf that contained illite or illite/smectite mixed-layer mineral with less chlorite. The temperatures of mineral formation calculated from the oxygen stable isotope data were slightly higher at some depths, but both calculated and measured temperatures demonstrated a steep, step-wise thermal gradient below the active hydrothermal field, where temperatures of >200 °C were determined at as little as 50 mbsf. Hydrogen isotope values mostly ranged between −40 and −55‰ and did not vary significantly or systematically between the layers, except in the clay fractions containing smectite above 25 mbsf that had relatively low values between −65 and −72‰. Hydrogen isotope results of the clay minerals were problematic to interpret and not consistent with interpretation of the oxygen data. Calculated temperatures from illite and smectite were mostly negative, whereas temperatures calculated from chlorite were more positive (average 145 °C), but lower than those from the oxygen isotope data. Additional work is still required to determine the hydrogen isotope fractionation between clay minerals and water with respect to temperature.

The Pb isotope compositions of galena in hydrothermal deposits obtained by drillings from two hydrothermal fields in the middle Okinawa Trough were studied. One of the study fields was the Iheya North field located on a volcanic complex and the other was the Izena field located in the sediment-filled caldera structure. LA-MC-ICP-MS was applied to directly measure Pb isotope compositions in individual galena grains which highlighted variations not only in regional scale, but also in microscopic scale so that changes of Pb isotope compositions within a galena grain can be tracked. Homogeneous Pb isotope compositions were found within the same hydrothermal site, irrespective of the mineral assemblage, texture and sampling depth beneath the seafloor. In contrast, the isotope compositions varied significantly between the two hydrothermal fields. The Pb isotope composition from the Iheya North field was isotopically close to the volcanic rocks of the Okinawa Trough, whereas that from the Izena field was more radiogenic with values intermediate between sediments and volcanic rocks of the Okinawa Trough. Within the Iheya North field, intra-field variation of Pb isotope compositions was recognized between two active sites 2.5 km apart from each other. The intra-field variation was recognized also in the Izena field. The sub-seafloor massive sulfide layer has a more sediment-like Pb isotope composition, compared to the inactive sulfide mound. These results illustrate that the Pb-mineralizing hydrothermal fluids originate from their local host rocks with/without sediment and that the isotope compositions of the galena grains reflect their metal sources; either the volcanic rocks and/or the sediments via water-rock interactions.

We observed the initial release rate of metals from four fresh (i.e., without long time exposure to the atmosphere) hydrothermal sulfide cores into artificial seawater. The sulfide samples were collected by seafloor drilling from the Okinawa Trough by D/V Chikyu, powdered under inert gas, and immediately subjected to onboard metal-leaching experiments at different temperatures (5 °C and 20 °C), and under different redox conditions (oxic and anoxic), for 1–30 h. Zinc and Pb were preferentially released from sulfide samples containing various metals (i.e., Mn, Fe, Cu, Zn, Cd, and Pb) into seawater. Under oxic experimental conditions, Zn and Pb dissolution rates from two sulfide samples composed mainly of iron disulfide minerals (pyrite and marcasite) were higher than those from two other sulfide samples with abundant sphalerite, galena, and/or silicate minerals. Scanning electron microscopy confirmed that the high metal-releasing sample contained several galvanic couples of iron disulfide with other sulfide minerals, whereas the low metal-releasing sample contained fewer galvanic couples or were coated by a silicate mineral. The experiments overall confirmed that the galvanic effects with iron disulfide minerals greatly induce the initial release of Zn and Pb from hydrothermal sulfides into seawater, especially under warm oxic conditions. Electronic supplementary material The online version of this article (10.1186/s12932-018-0060-9) contains supplementary material, which is available to authorized users.

Artificial hydrothermal vents, created by boreholes that discharge hydrothermal fluids and useful for observing secular changes in mineral precipitates and the chemical compositions of hydrothermal fluids, are periodically cleaned of scale deposits. Here, we report petrographic and geochemical features of hydrothermal scale with a concentric structure and extreme enrichment in Zn, recovered as an intact plug from an artificial hydrothermal vent pipe in the Okinawa Trough. The scale consists of sphalerite with accessory galena and chalcopyrite, and minor cotunnite (PbCl2), barite, an unidentified Zn sulfate, and Bi-rich minerals. It comprises at least five concentric layers alternating between thin, reddish-brown porous layers composed of relatively Fe-rich sphalerite accompanied by galena and chalcopyrite, and coarse-grained, dark gray layers dominated by relatively Fe-poor sphalerite. Cotunnite occurs only in the innermost reddish-brown layer, and barite occurs only in the uppermost and innermost layers. The scale is composed of > 50 wt% Zn, several wt% Fe and Pb, and

We observed crack generation and structural changes in electroless nickel–phosphorus (Ni–P) plating layers formed on copper-metalized silicon nitride substrates both during thermal cycling from − 40 to 250 °C and during storage (not cycling) at 250 °C in order to investigate the effect of the phosphorus contents on crack generation and growth in the Ni–P platings. The used platings contained phosphorus at three different contents: 2.1 wt% [Ni–P(low)], 6.5 wt% [Ni–P(med)], and 10.9 wt% [Ni–P(high)]. The generation time and the amount of cracks were strongly dependent on their phosphorus contents. More cracks appeared after thermal cycling than after storage at 250 °C. In Ni–P(low), cracks were generated after 200 thermal cycles, whereas no cracks were observed even after 250 h of storage at 250 °C. In Ni–P(med) and Ni–P(high), both during thermal cycling and storage at 250 °C, cracks formed during or after crystallization of the amorphous layers. These results suggest that the primary factors affecting the generation of cracks in electroless Ni–P platings are crystallization of the Ni–P platings and repeated changes in thermal stress.

Effect of silver (Ag) catalyst in bioleaching of enargite (Cu_3AsS_4) concentrate was studied using mixed cultures of moderately thermophilic acidophilic microorganisms at 45ºC. Addition of Ag_2S enabled selective Cu dissolution from enargite while suppressing pyrite oxidation: At the highest Ag_2S concentration of 0.04%, Cu recovery reached 96% while Fe dissolution was suppressed to reach only 29% by day 72. Overall results from thermodynamic calculation, liquid/solid analyses and kinetic study suggested that Ag-catalyzed bioleaching of enargite concentrate proceeds via formation of at least two types of secondary products (chalcocite, Cu_2S; trisilver arsenic sulfide, Ag_3AsS_4): Addition of Ag_2S as Ag catalyst thermodynamically and microbiologically contributed to lowering solution redox potentials during bioleaching, consequently satisfying Eox (Cu_2S) < E_h < E_c (Ag+) to enhance enargite dissolution via formation of chalcocite intermediate. Formation of trisilver arsenic sulfide and its intermediate layer (Cu,Ag)_3AsS_4 indicated that Cu ion in the enargite lattice is gradually substituted with Ag. Such secondary products did not impose a rate-limiting step, since the Ag-catalyzed bioleaching was shown to be controlled by a chemical surface reaction, rather than diffusion through product film which was the case in the absence of Ag_2S.

Au and As concentrations in pyrite grains from the Hishikari deposit were extensively determined by secondary ion mass spectrometry (SIMS) and electron probe microanalysis (EPMA) to investigate the microscale relationship between Au and As. The low-sulfidation epithermal Hishikari deposit, which has produced more than 224 t of gold since 1985 (as of March 2016), is world-famous for its high-grade ore. Accurate quantitative SIMS analyses of Au in pyrite were possible by preparing an Au-implanted pyrite standard sample and by using a properly tuned SIMS analytical method. An analysis size of 3 μm was chosen since the pyrite grains from the Hishikari deposit have heterogeneous As concentrations. This paper presents the first comprehensive data set of Au and As concentrations in a 3 μm area of pyrite obtained from the widely distributed high-grade Au-bearing Hishikari veins. Microanalyses of arsenian pyrite from the Hishikari gold deposit by SIMS and EPMA revealed that Au concentrations of 0.1–2800 ppm are positively correlated with As concentrations of 0 to 7 wt% in a 3 μm area. The formation of Hishikari veins is divided into two stages that are further subdivided into the early and late sub-stages. The rim of a pyrite grain precipitates after formation of the core; however, the time scale of core and rim formation is far shorter than that of the entire mineralization sequence. The specific value of the Au/As ratio in pyrite proves to be characteristic of the specific Au-bearing vein and its specific depth. Therefore, it could be possible to infer the nature of unknown veins by the Au/As ratio obtained. Although the Au/As ratio varies from vein to vein, a general tendency is observed for each ore zone of the Hishikari deposit. The Au/As ratio is high in the Sanjin ore zone, which consists of numerous high-grade veins in or above the Cretaceous accretionary sedimentary rocks of the Shimanto Group. The Au/As ratio is moderate in the Honko ore zone, which consists of several high-grade veins and also occurs in or above the basement sedimentary rocks. On the other hand, the Yamada ore zone, which consists of relatively low-grade veins, occurs in Pleistocene andesitic pyroclastic rocks that overlie the basement sedimentary rocks unconformably. The Au/As ratio in pyrite of the Yamada ore zone is relatively low compared with that of other ore zones. Several previous papers have proposed that the As− in pyrite may contribute to the reduction of Au+ to Au0 as Au nanoparticles (NPs) by As oxidation; however, Au and As concentrations of arsenian pyrites fall on or below the Au solubility limit in this study. Moreover, the As and S concentrations in pyrite are inversely correlated, which is consistent with the substitution of As for S as anionic As− in the Fe(S1−xAsx)2 solid solution of natural arsenian pyrite under reducing environments. The present study suggests that the Hishikari Au exists as a solid solution in the Hishikari arsenian pyrite, although there remains a possibility that it exists partially in the form of NPs even though the Au and As concentrations of arsenian pyrites fall on or below the Au solubility limit.

The reliability of metallized ceramic substrates at high temperatures has been one of the main issues for high-power semiconductor modules. Cracks generated in the nickel plating layers, which prevent oxidation of the metal conductor layers, reduce the reliability. Thus, we evaluated the cracks generated in electroless nickel plating layers on copper-metallized silicon-nitride substrates subjected to thermal cycles of three different temperature ranges in air. The different temperature ranges for the thermal cycles were −40 to 150 $${}^{\circ }\text{C}$$ , −40 to 200 $${}^{\circ }\text{C}$$ , and −40 to 250 $${}^{\circ }\text{C}$$ . The results indicated that the cracks were generated in the Ni layers after 500 thermal cycles in the temperature range of −40 to 250 $${}^{\circ }\text{C}$$ . These cracks penetrated the Ni layer completely and extended into the Cu layers to a depth of several micrometers. Copper oxide formed under the cracks, part of which ascended through the cracks and deposited on the surface of the Ni layers due to the volume expansion during oxidation. On the other hand, no cracks were observed on the surface of the Ni layers even after 1000 thermal cycles when the upper limit of temperature was 200 $${}^{\circ }\text{C}$$ or lower. The thermal cycles with the upper limit of temperature at 250 $${}^{\circ }\text{C}$$ or higher strongly affected the formation of cracks in the Ni plating layers.

Meteorite impacts have caused catastrophic perturbations to the global environment and mass extinctions throughout the Earth’s history. Here, we present petrographic and geochemical evidence of a possible impact ejecta layer, dating from about 11 Ma, in deep-sea clayey sediment in the Northwest Pacific. This clay layer has high platinum group element (PGE) concentrations and features a conspicuous negative Os isotope anomaly (187Os/188Os as low as ~0.2), indicating an influx of extraterrestrial material. It also contains abundant spherules that include pseudomorphs suggestive of porphyritic olivine as well as spinel grains with euhedral, dendritic and spherical forms and NiO contents as great as 23.3 wt%, consistent with impact ejecta. Osmium isotope stratigraphy suggests a most plausible depositional age of ~11 Ma (Miocene) for this layer, as determined by fitting with the seawater evolution curve. No large impact crater of this age is known on land, even within the relatively large uncertainty range of the relative Os age. Thus, we suggest that an unrecognised impact event in the middle or late Miocene produced the impact ejecta layer of the Northwest Pacific.

The thermal stress in metal conductor layers strongly influences the reliability of high-power electrical modules. We evaluated the stress behavior of copper paste films, which were sintered on alumina substrates, during repeated thermal cycles. The thermal cycle tests were performed from room temperature to 500 °C, which was lower than the sintering temperature. As the number of cycles increased, there was an increase in the temperature at which the compressive stress reached a maximum during heating and there was an increase in the tensile stress during cooling. However, the magnitude of increase reduced as the number of thermal cycles increased. On the other hand, the stress-change rates in the elastic region remained unchanged though the films were subjected to the thermal cycles. We surmised that these changes were owing to an increase in the dislocation density due to plastic deformation, grain refinement due to the increase in the dislocation density, and restoration processes in the copper paste films.

Aim: The correct diagnosis of the functional capacity of human sperm is limited. The Sperm Quality Analyzer (SQA) with the visualization system (SQA V, Medical Electronic System, Hatavorzo, Israel), an upgraded version of SQA, was recently developed to provide a rapid and low‐cost quantitative evaluation of sperm quality as well as sperm velocity assessment. The aim of the present study was to evaluate whether the SQA V's new parameters correlate with computer‐aided sperm analysis (CASA) estimates.

Iheya-North-Knoll is one of the small knolls covered with thick sediments in the Okinawa Trough back-arc basin. At the east slope of Iheya-North-Knoll, nine hydrothermal vents with sulfide mounds are present. The Integrated Ocean Drilling Program (IODP) Expedition 331 studied Iheya-North-Knoll in September 2010. The expedition provided us with the opportunity to study clay minerals in deep sediments in Iheya-North-Knoll. To reveal characteristics of clay minerals in the deep sediments, samples from the drilling cores at three sites close to the most active hydrothermal vent were analyzed by X-ray diffraction, scanning electron microscope and transmission electron microscope. The sediments are classified into Layer 0 (shallow), Layer 1 (deep), Layer 2 (deeper) and Layer 3 (deepest) on the basis of the assemblage of clay minerals. Layer 0 contains no clay minerals. Layer 1 contains smectite, kaolinite and illite/smectite mixed-layer mineral. Layer 2 contains chlorite, corrensite and chlorite/smectite mixed-layer mineral. Layer 3 is grouped into three sub-layers, 3A, 3B and 3C; Sub-layer 3A contains chlorite and illite/smectite mixed-layer mineral, sub-layer 3B contains chlorite/smectite and illite/smectite mixed-layer minerals, and sub-layer 3C contains chlorite and illite. Large amounts of di-octahedral clay minerals such as smectite, kaolinite, illite and illite/smectite mixed-layer mineral are found in Iheya-North-Knoll, which is rarely observed in hydrothermal fields in mid-ocean ridges. Tri-octahedral clay minerals such as chlorite, corrensite and chlorite/smectite mixed-layer mineral in Iheya-North-Knoll have low Fe/(Fe + Mg) ratios compared with those in mid-ocean ridges. In conclusion, the characteristics of clay minerals in Iheya-North-Knoll differ from those in mid-ocean ridges; di-octahedral clay minerals and Fe-poor tri-octahedral clay minerals occur in Iheya-North-Knoll but not in mid-ocean ridges.

The mechanical properties of metal conductor layers strongly influence the reliability of high-power electrical modules. In this study, the microstructure, elastic modulus, and residual stress during temperature cycling of screen-printed sintered paste films were evaluated to develop guidelines for designing metal conductor layers to the module. The number of pores decreased and the elastic modulus increased for paste films sintered at higher temperatures. These films deformed plastically at lower temperatures when heated from room temperature; those that had been sintered at the highest temperature of 800 °C showed the highest maximum compressive stress, which was still approximately one third smaller than that of copper electroplated films. All films developed creep deformation above 200 °C during both heating and cooling processes. The substrate under the film was considered to affect the residual stress in the elastic-deformation area owing to its coefficient of linear thermal expansion and to not affect the residual stress in the creep-deformation area.

Effectiveness of different pure and mixed cultures of three moderately thermophilic, extremely acidophilic bacterial strains (Acidimicrobium ferrooxidans ICP, Sulfobacillus sibiricus N1, Acidithiobacillus caldus KU) were investigated for biooxidation of highly refractory polymetallic gold ore concentrates. Despite of its complex mineralogy and the presence of a mixture of potentially inhibitory metals and metalloids, the concentrate was readily dissolved in defined mixed cultures including both iron and sulfur oxidizers, releasing as much as 80% of soluble Fe and 61% of soluble As. Factors to affect microbial mineral dissolution efficiencies (i.e. microbial As(III) oxidation ability, formation of secondary mineral precipitation (e.g. jarosite, elemental sulfur, scorodite, anglesite), and microbial population dynamics during biooxidation) were studied, based on which roles of individual microbes and their synergistic interactions during biooxidation were discussed. Applying the biooxidation pretreatment us...

Al-doped ZnO spherical nanoparticles were synthesized using a polyol method, and the particle sizes and absorption spectra from the ultraviolet to the near-infrared were investigated in detail. Al-doped ZnO spherical nanoparticles with sizes of about 70 nm were obtained, with zinc–aluminum layered double hydroxide as a by-product. The aluminum concentration of the obtained nanoparticles was approximately 1.3% whether the starting aluminum concentration was 2% or 10% in the polyol process, suggesting that 1.3% is the solid solubility limit of Al in ZnO. A homogeneous Al-distribution, a peak shift in an X-ray diffraction pattern, and some near-infrared absorption reveal that aluminum ions were doped in the ZnO lattice. When the synthesis temperature was 150 °C for the polyol process without heat treatment, we obtained Al-doped ZnO spherical nanoparticles not only with high transparency in the visible light region but also with absorption properties in the ultraviolet and near-infrared.

Seafloor hydrothermal systems in the back-arc region of the Okinawa Trough have been viewed as a modern analogue to the Kuroko-type volcanogenic massive sulfide deposits. Detection of magnetic signatures is widely utilized and assumed to facilitate the understanding of geological controls on hydrothermal system genesis. However, the magnetic properties of seafloor volcanic rocks are still poorly understood because of the difficulties of sample acquisition. Here, we report rock magnetic data along with linked geochemical and petrological data of volcanic rock samples obtained from the Irabu knolls of the southern Okinawa Trough. Both fresh and hydrothermally altered basaltic andesites were successfully obtained from the seafloor via submersible. A fresh sample, with single-domain titanomagnetite grains, is strongly magnetized with NRM intensity of up to 100 A/m. Minute skeletal and dendritic titanomagnetite grains are also observed. A second fresh sample, with multi-domain titanomagnetite grains, contains a greater amount of titanomagnetite grains, but exhibits NRM intensity ~ 10 A/m at most. In contrast to the fresh samples, hydrothermally altered samples show extremely low NRM intensities along with low saturation magnetization and certain contribution of paramagnetic minerals. Grain assemblages of pyrite and chalcopyrite grains appear along cracks in the groundmass. Our results indicated that fine titanomagnetite grains in groundmass within back-arc lava flows are altered due to hydrothermal processes. The recorded primary remanent magnetization of the lava flows is thus partly removed by hydrothermal alteration. Magnetization reduction related to hydrothermal activity produces local crustal magnetization lows and thus enables us to detect hydrothermal alteration zones by utilizing magnetic field measurements in space. In particular, the lavas we examined (via their resultant basaltic andesites) have high Curie temperatures greater than 400 °C, which is significantly higher than those indicated by mid-ocean ridge basalts, suggesting that the thermal effect for crustal magnetization may be less in back-arc settings.

Shallow-water hydrothermal activity, represented by venting of hydrothermal fluid around 200 °C, occurs in the Wakamiko submarine crater at 200 m water depth in Kagoshima Bay, southwest Japan. The crater is the center of large eruptions that formed a volcanic caldera, which is semi-submerged at present. The crater is covered with thick volcanic sediments of felsic composition. We studied the distribution and chemical composition of hydrothermal clay minerals that are abundant in the sediment collected by piston coring. We also conducted chemical analysis of pore fluids squeezed from the sediment to understand hydrothermal interactions that resulted in formation of these clay minerals. The PC-2 core (340 cm in length) collected in the vicinity of a high-temperature fluid venting site was characterized by abundant Mg-saponite that is limited to a layer between 270 and 300 centimeters below the seafloor (cmbsf) and montmorillonite throughout the core below 55 cmbsf. Vertical profiles of pore fluid chemistry suggest that saponite formation is related to the interface between the seawater and the hydrothermal component in the sediment layer. Formation temperatures of the montmorillonite were estimated to be 118–163 °C, based on oxygen isotope thermometry. Formation of the montmorillonite is attributed to hydrothermal interaction between seawater-dominant pore fluid and volcanic glass. The formation temperature of the saponite was estimated to be ~ 164 °C, based on oxygen isotope thermometry. Formation of the saponite is attributed to hydrothermal interaction between seawater-dominant pore fluid and the montmorillonite, which had been formed at a prior stage. The PC-1 core (240 cm in length) collected from a relatively low-temperature fluid shimmering site was characterized by the occurrence of kerolite in the lower section (210–240 cmbsf). Vertical profiles of pore fluid chemistry suggest that the kerolite formation occurred at the interface between seawater and the hydrothermal component of the sediment layer. Formation temperature of the kerolite was estimated to be about ~ 211 °C, based on oxygen isotope thermometry. Formation of the kerolite is attributed to precipitation from a fluid that was a mixture of a hydrothermal component and seawater. This study revealed the occurrence of Mg-rich clay minerals, saponite and kerolite, beneath a submarine hydrothermal field that developed within sediment of felsic composition. During hydrothermal interactions that formed these clay minerals, seawater penetrated into the sediment and was an important Mg source. Formation of Mg-rich clay minerals, saponite and kerolite, are controlled by pore fluid chemistry, which varies from a seawater-dominant to hydrothermal-dominant component. Exclusive formation of Mg-rich clay minerals at different sites could be explained by different water–rock ratios of the hydrothermal interaction — saponite formation at low water-rock ratio and kerolite precipitation at high water–rock ratio. Occurrence of Mg-rich clay minerals provides clues to the hydrological structure in sediment-covered hydrothermal systems in an arc volcanic caldera setting.

Continuous indium tin oxide (ITO) films of as low as 10 Ω/□ and up to ~ 2 μm thick were prepared by forming a laminate structure of alternating indium tin complex and ITO nanoparticle layers on a substrate by solution deposition then thermal transformation of the precursor film to ITO. The characteristic formation of a dense ITO layer on the surface of ITO films was observed upon decomposition of 3,4-dihydroxybenzoate ester complexes of indium tin, which were found to become more crystalline when transformed under a reduced oxygen atmosphere at a controlled heating rate. The observed dense ITO skin formation characteristic was used in combination with sequential direct transfer to a reductive atmosphere in a two zone inline kiln to give low resistance stacked ITO films in a one-bake process. Photo-patternable indium tin complexes were also used to form the dense ITO skin on top of the stacked structure.

The reliability of electronic substrates at high temperature is a significant issue for high-power semiconductor modules. To improve the reliability, it is essential to understand and reduce thermal-cycling-induced surface roughening of metal layers on the substrates. We observed the surfaces and cross sections of nickel plating layers on copper-metallized silicon nitride substrates by active metal brazing after the substrates were subjected to thermal cycles of −40 to 250°C. No cracks were observed on the surfaces of the nickel layers on substrates that were subjected to 100 and 200 thermal cycles. However, voids or cavities were observed just under the nickel surfaces on those substrates. We considered that those voids or cavities were formed by thermal stress induced by thermal cycling and that they could be one of the origins of cracks in the nickel layers.

Seafloor massive sulphide deposits are potential resources for base and precious metals (Cu-Pb-Zn ± Ag ± Au), but difficulties in estimating precise reserves and assessing environmental impacts hinder exploration and commercial mining. Here, we report petrological and geochemical properties of sulphide chimneys less than 2 years old that formed where scientific boreholes vented hydrothermal fluids in the Iheya-North field, Okinawa Trough, in East China Sea. One of these infant chimneys, dominated by Cu-Pb-Zn-rich sulphide minerals, grew a height of 15 m within 25 months. Portions of infant chimneys are dominated by sulphate minerals. Some infant chimneys are sulphide-rich similar to high-grade Cu-Pb-Zn bodies on land, albeit with relatively low As and Sb concentrations. The high growth rate reaching the 15 m height within 25 months is attributed to the large hydrothermal vent more than 50 cm in diameter created by the borehole, which induced slow mixing with the ambient seawater and enhanced efficiency of sulphide deposition. These observations suggest the possibility of cultivating seafloor sulphide deposits and even controlling their growth and grades through manipulations of how to mix and quench hydrothermal fluids with the ambient seawater.

Palladium, cobalt, and nickel in complex with photoacid-generating ligands, 4-(2-nitrobenzyloxycarbonyl)catechol and 4-(6-nitroveratryloxycarbonyl)catechol, were prepared in solution. Films formed from the metal complex solutions perform as positive-tone, directly photopatternable palladium, cobalt, nickel oxide, or composite film precursors. After exposure, acid-bearing selectively soluble complexes could be removed to give patterned films upon developing in aqueous base, which were transformable to the corresponding pattern-preserving metal/metal oxide film. The photodynamics of photoinduced solubility and direct micropatterning of palladium, cobalt, nickel, and palladium/nickel oxide composite films were investigated. Employing palladium as the initiator for autocatalytic chemical plating, selective direct copper plating on palladium film on polyethylene naphthalate and palladium/nickel oxide composite film on glass was accomplished.

The efficiency of positive-tone directly photo-patternable 4-(2-nitrobenzyloxycarbonyl)catechol and 4-(6-nitroveratryloxycarbonyl)catechol complexes of indium tin was improved by tuning the solubility of the complexes and by chelation of maltol as a cooperative photo-solvolytic component, such that films could be patterned at up to 4.88 mW·s/nm in terms of resultant indium tin oxide (ITO). Patterned indium tin complexes were thermally transformed to pattern shape preserved ITO by anisotropic contraction and oxidation. The photo-reaction of these ligands and related derivatives was characterized by nuclear magnetic resonance analysis showing decomposition to the respective carboxylic acid for which linear rate constants were approximated, further elucidating the mechanism and mechanics of selective solubility.

Petrography, isocon analysis and singular value decomposition analysis of jadeitites and metasomatic rocks surrounding them from the Nishisonogi metamorphic rocks revealed that the metasomatic rocks developed outside the stability field of jadeite + quartz after jadeitites had been included by a serpentinite melange in a subduction channel possibly during exhumation. The jadeitites occur at two localities, Tone and Mie in Nagasaki City, from a serpentinite melange in the Nishisonogi metamorphic rocks. The jadeitite mineral assemblage is jadeite/omphacite + paragonite + phlogopite + albite + clinozoisite/epidote ± muscovite ± analcime. Jadeite core with fine-grained quartz inclusions and the inclusion-free rim is partially replaced by albite. These jadeitites are surrounded by metasomatic zones of albitites and/or a muscovite rock. The mineral assemblage of the albitites is albite + clinozoisite/epidote ± muscovite ± omphacite ± phlogopite ± amphibole ± chlorite, and that of the muscovite rock is muscovite + clinozoisite + chlorite. Because these zones have no high-pressure minerals, they represent products in a P – T regime outside the stability field of jadeite + quartz. Isocon analyses between the jadeitites and the metasomatic zones reveal that K 2 O, H 2 O, Sr and Ba were added to jadeitite and SiO 2 , Na 2 O and Fe 2 O 3 were removed. REE-rich veinlets emanate from clinozoisite grains, suggesting REE mobility during the fluid–jadeitite interactions. The metasomatic zones developed by interaction between jadeitites and serpentinite via K-, Sr- and Ba-rich fluid, during exhumation from the stability field of jadeite + quartz through that of albite to that of analcime.

Two types of omphacitites are distinguished in ultramafic melanges that are intercalated with epidote–blueschist facies schists of the Nishisonogi metamorphic rocks in western Kyushu, Japan. One is an omphacitite layer in a metabasite block, and the other is an omphacitite lens in an albitite block. These omphacitites are principally composed of omphacite with minor amounts of winchite/magnesiohornblende, epidote, albite and titanite. Although the petrographic features of both types are similar, the omphacitite layer is depleted in light rare earth elements (LREE; La, Ce and Nd) compared with the omphacitite lens. In the case of jadeitites, those interpreted as being formed by direct precipitation from aqueous fluids are LREE-depleted, while those interpreted as being formed by metasomatic replacement from protoliths are LREE-enriched. Thus, by analogy, the omphacitite layer may have directly precipitated from aqueous fluids, and the omphacitite lens may be metasomatic in origin. The omphacitite layer has amphibole-rich selvages, which are likely formed by the reaction between the omphacitite-forming fluid and the host metabasite. Mass-balance analysis using the isocon method indicates that the formation of the selvages involves additions of large ion lithophile elements (LILE; Rb, K and Ba), Na and Si to the host metabasite. These components were likely introduced via fluid infiltration. Although the source of the omphacitite-forming fluid is not clear, the LILE-rich composition suggests participation of fluids derived from metapelitic rocks.

On the basis of internal structures, laser ablation U–Pb ages and trace element compositions, the origin of zircon in jadeitite in the Nishisonogi metamorphic rocks was examined. The zircon comprises euhedral zoned cores overgrown by euhedral rims. The cores contain inclusions of muscovite, quartz, albite and possibly K-feldspar, yield 238U–206Pb ages of 126 ± 6 Ma (±2 SD, n = 45, MSWD = 1.0), and have Th/U ratios of 0.48–1.64. The rims contain inclusions of jadeite, yield 238U–206Pb ages of 84 ± 6 Ma (±2 SD, n = 14, MSWD = 1.1), and have Th/U ratios of

Citation Hirano Y, Shibahara H, Koriyama J, Tokunaga M, Shimada K, Suzuki M. Incidence of sperm-immobilizing antibodies in infertile women with past Chlamydia trachomatis infection. Am J Reprod Immunol 2011; 65: 127–132 Problem Among the risk factors for antisperm antibody production, inflammatory diseases of the genital tract are believed to play an important role. Chlamydia trachomatis infection is one of the most common sexually transmitted diseases. There are some reports suggesting that human sperm have antigens that cross-react immunologically with certain microbial antigens, such as C. trachomatis. However, this is still controversial. We performed a retrospective study to investigate the correlation between anti-chlamydial antibodies and sperm-immobilizing antibodies in infertile women. Method of study Between January 2007 and March 2009, the presence of sperm-immobilizing antibodies was examined by the sperm immobilization test using sera from 273 infertile women. Anti-chlamydial antibodies (IgG and IgA) were examined to prove past C. trachomatis infection by ELISA using the same sera from infertile women. Results The overall incidence of sperm-immobilizing antibodies was 2.9% (8/273) in infertile women. The incidences of sperm-immobilizing antibodies were 6.4% (5/78) in cases with past C. trachomatis infection and 1.5% (3/195) in cases without past C. trachomatis infection. There was a significant difference between the two groups (P = 0.031). Conclusion A significantly higher incidence of sperm-immobilizing antibodies was noted in infertile women with past C. trachomatis infection compared with that of those without past C. trachomatis infection. This is the first demonstration that C. trachomatis infection could play a role in the production of sperm-immobilizing antibodies in infertile women.

Gas in an infected organ generally indicates a severe infection, often requiring surgery; however, data are lacking as to post-cesarean gas-forming uterine infection. A 27-year-old Japanese primigravida underwent a difficult cesarean section, after which a high fever continued. Computed tomography (CT) revealed marked gas in the uterine anterior myometrium. Diagnosing this condition as post-cesarean uterine scar infection, we recommended surgical intervention, that is, hysterectomy or at least drainage; however, the patient refused it. Considering the patient's desire and lack of organ-failure signs, we employed intensive antibiotic treatment for 6 weeks. Serial CT indicated a gradual decrement in the gas amount and she recovered completely after 8 weeks. This case suggests that surgical procedure may not always be necessary for post-cesarean gas-forming uterine infection and CT may be useful to detect/follow this condition.

Gold occurs as both electrum (a natural alloy of gold and silver) and invisible gold in arsenian pyrite in the Hishikari epithermal gold deposit in Japan. Microanalyses of arsenian pyrite from the deposit using secondary ion mass spectrometry (SIMS) and electron probe microanalysis (EPMA) revealed that Au concentrations (0.1–2600 ppm) are positively correlated with As concentrations (0.0–6.1%). A small (3 μm) area of pyrite was analyzed because the sample textures were fine and complicated. The Au/As ratio is high in the Sanjin ore zone, which has very high-grade veins, while the ratio is low in the Yamada ore zone, which has average-grade veins.

Kusatsu hot springs at the eastern foot of the Kusatsu-Shirane volcano is a famous spa area in Japan. Its hot springs are strongly acidic making local rivers acidic, requiring lime water neutralization. We determined the arsenic concentration in hot springs, rivers, and neutralization products, to calculate the mass balance of arsenic in river systems. Hot springs supply a total of 45 tons a year in arsenic to local rivers, which transport some 28 tons a year — most of which is accounted for by Bandaiko hot spring and the Yu River. After neutralization, these flow into the Shinaki Dam reservoir, which accumulates large amounts of suspended neutralization products. Mass balance calculation suggests that arsenic dissolved in river water is nearly completely coprecipitated with or adsorbed by neutralization products, so that Shinaki Dam reservoir accumulates some 25 tons of arsenic yearly.

Submarine hydrothermal fluid emanation from a small sediment mound associated with bubbling gas was observed in the Wakamiko crater that is located 5 km offshore at 200 m depth in Kagoshima bay, southern Kyushu, Japan. In 2003 and 2005, surface sediments (up to 30 cm) from inside and outside of the hydrothermal mound were sampled using the submersible ROV Hyper-Dolphine (JAMSTEC). Chemistry of pore fluids inside the mound showed a clear difference from those collected from outside the mound, which is explained by mixing of the ascending hydrothermal component and seawater. Estimated chemical composition of the hydrothermal end member suggests that the fluid experienced hydrothermal interaction at a temperature range of about 175 to 200 °C. This is consistent with the observed mound temperature of 137 °C. Hydrothermal minerals such as barite, stibnite, and realgar were identified in the mound sediment, suggesting their precipitation due to mixing of the ascending hydrothermal fluid with seawater. Isotopic composition of the hydrothermal endmember can be explained by mixing product of seawater, magmatic water and meteoric water. The marine shallow-water hydrothermal system in the Wakamiko crater is considered to be driven by a magmatic heat source beneath the crater, which also contributes elements such as arsenic, antimony, mercury and magmatic water to the hydrothermal fluid.

Aim: Transvaginal hydrolaparoscopy (THL) has recently been developed as a less invasive alternative to conventional laparoscopy. There are some reports that described the usefulness and prognostic value of diagnostic THL in infertile women. Moreover, operative THL such as ovarian drilling for unovulatory women with polycystic ovarian syndrome (PCOS) to induce ovulation has also been found to be as effective as that by conventional laparoscopy. The risk of bowel injury and sepsis by transvaginal access with culdoscopy was higher than that with laparoscopy in the previous reports. The purpose of the present study was to examine the risk of diagnostic and operative THL according to two case studies with a literature review. Methods: The authors carried out diagnostic or operative THL in 177 infertile women, aged 22–43 years. Major complications during THL and a review of the literature were analyzed. Results: Two cases of bowel injury were diagnosed during diagnostic THL. No complication occurred during operative THL. In total, the incidence of bowel injury was 1.1%. The injuries were diagnosed during THL and treated expectantly under strict conditions in both cases. Ten studies in the literature reported a total of 4232 procedures, including 26 bowel injuries (0.61%) and one perforation of a retroflexed uterus (0.02%). Conclusions: The usefulness of THL for diagnostic and operative purposes is in no doubt. However, informed consent should be obtained and vigilance before and during THL should be maintained, although it can be done on an outpatient clinic basis.

Aim: Elective transfer of two good-quality embryos has been used to avoid triplet or high-order multiple pregnancies. However, the rate of twin pregnancies has remained fairly unchanged. In the present study, criteria for elective single embryo transfer (eSET) at day 2 or day 3 were established by analyzing cases with successful implantation of all embryos transferred. Methods: A total of 685 fresh or frozen-thawed embryo transfers following in vitro fertilization/intracytoplasmic sperm injection between April 2002 and March 2006 were performed. Only embryo transfers at day 2 or day 3, but not at blastocyst stage, were included. Successful implantation of all embryos transferred was obtained in 17 pregnancy cycles. Results: Thirty-one gestational sacs with fetal heartbeats were obtained by a total of 31 embryo transfers in 17 infertile women. The average age was 32.6 years (23–38), and 14 (82.3%) of the 17 women were

Aims It has been shown that supplementation of patients’ sera that contains sperm-immobilizing antibodies results in failure of fertilization and embryo developmentin vitro. The present study was carried out to investigate if exposing retrieved eggs to a high number of sperm-immobilizing antibodies in the follicular fluid (FF)in vivo affected subsequent fertilization and embryo developmentin vitro, even if they were washed with an antibody-free culture medium.