Lacydonia Marion & Bobretsky, 1875 is the sole genus in the family Lacydoniidae Bergström, 1914. We herein describe the new species of Lacydonia shohoensis sp. nov. from 2042-m deep bottoms at Shoho Seamount of the Nishi-Shichito Ridge, the Northwest Pacific Ocean. It is most similar to L. anapaulae Rizzo et al., 2016 in having a depression on the median anterior region and lacking lateral lobes on the posterior margin of prostomium whereas it is distinguished by possessing pygidium dorsally pigmented with three reddish spots and non-pigmented pygidial lateral cirri equally elongated.

It is well known that sea urchin embryos treated with lithium chloride (LiC1) develop to abnormally into vegetalised embryos, in which differentiation of ectodermal cells is inhibited. When embryos of the sea urchins, Hemicentrotus pulcherrimus and Anthocidaris crassispina were treated with 20 mM LiC1 from the 8-cell stage to the corresponding early gastrula stage, they developed to vegetalised embryos with a large exogut 45 h after fertilisation. In these vegetalised embryos, high activity of alkaline phosphatase (AP) was detected histochemically at the end of the exogut where it is attached to the embryo body. High activity of AP is known to be detected specifically in the gut of sea urchin pluteus larvae by the same procedure as used in this study. Hence, we concluded that this part of the exogut is composed of the cells which develop into the cells of the gut in normal development.

When exogut isolated from vegetalised embryos was cultured in the extract obtained from eggs or embryos, the end composed of the cells in which high AP activity was detected, expanded during culture and formed a large spherical structure about 24 h after the initiation of culture. The minimum concentration of extract to cause expansion of isolated exogut was 5 × 103 egg or embryo equivalent/ml ASW (artificial seawater). The extract boiled at 95 °C for 1 h also caused expansion of isolated exogut at the same concentrations as non-boiled extract. On the other hand, the extract obtained from eggs or embryos by chloroform–methanol extraction did not cause any expansion of exogut, but the aqueous phase, heat-dried and dissolved in ASW, induced expansion of isolated exogut.

We explore some aspects of the optimization of amorphous semiconductors as well as low- and high-dielectric-constant (low-/high-k) materials viewed purely from the perspective of percolation and topological constraint theories. We specifically illustrate how percolation, constraint theory, and mean network coordination, 〈r〉, play underlying roles in determining the electrical and mechanical properties of amorphous semiconducting and dielectric materials as well as interfaces that are important for modern micro-/nanoelectronic devices.

The galatheid crab Shinkaia crosnieri, is the sole member of the subfamily Shinkaiinae. It is abundant and forms dense beds around active hydrothermal vents in the Okinawa Trough. Thousands of filamentous bacteria attached to the plumose setae on the ventral surface of this crab were observed using field-emission scanning electron microscopy and transmission electron microscopy. Nucleic acids were extracted from the filamentous bacteria, and the phylotypes of 16S rRNA genes were identified from 81 clones. These phylotypes were divided into three groups: Epsilonproteobacteria (74%); Gammaproteobacteria (20%); and Bacteroidetes (6%). Gamma- and major phylotypes of Epsilonproteobacteria were also detected using fluorescence in situ hybridization analysis. These Epsilon- and Gammaproteobacteria were closely related to cultured and uncultured bacteria from hydrothermal vent fields including episymbionts of vent-associated invertebrates such as Rimicaris exoculata, Alvinella pompejana, the scaly-foot snail, Kiwa hirsuta etc. The carbon isotopic compositions of the muscle of S. crosnieri and in filamentous bacteria were similar. The muscle of S. crosnieri contained monounsaturated C16 and C18 fatty acids, which are known to be characteristic of sulphur-oxidizing bacteria in H2S-rich marine habitats. Through the video images transmitted by a submersible and a remotely operated vehicle, S. crosnieri was observed to comb out its ventral setae using the third maxilliped and appeared to consume the contents. These evidences suggest the epibiotic association between S. crosnieri and the filamentous bacteria attached to the ventral setae of the crab, but the details of role and function are still unclear at the present study.

Our preliminary clinical trial showed that consumption of cooked rice of a Japanese common cultivar Yukihikari improved atopic dermatitis associated with a suspected rice allergy, although the underlying mechanisms remain unclear. We hypothesised that the ameliorating effect of Yukihikari on atopic dermatitis is associated with the gut microbiota. BALB/c mice were fed a synthetic diet supplemented with uncooked and polished white rice powder prepared from one of four different cultivars: Yukihikari, rice A (common rice), rice B (brewery rice) and rice C (waxy rice). Denaturing gradient gel electrophoresis of PCR-amplified 16S rRNA gene fragments showed that the composition of faecal microbiota was different between mice fed Yukihikari and those fed rice A. Analysis of the 16S rRNA clone library and species-specific real-time PCR showed that the abundance of Akkermansia muciniphila, a mucin degrader, tended to be lower in mice fed Yukihikari. The incidence of allergic diarrhoea induced by oral administration of ovalbumin in systemically immunised mice was lower in mice fed Yukihikari, albeit with no difference in serum antibodies specific to ovalbumin. In a separate experiment, serum antibody levels specific to orally administered ovalbumin were lower in mice fed Yukihikari. Additionally, the translocation of horseradish peroxidase in isolated segments of ileum and colon tended to be lower in mice fed Yukihikari, suggesting a reduction in gut permeability in mice fed Yukihikari. These data indicate that changes in the gut microbiota of mice fed Yukihikari could be advantageous in the prevention of food allergy.

The thermosphere is the transition region from the atmosphere to space. Both the solar ultraviolet radiation and the solar wind energy inputs have caused significant thermospheric variations from past to present. In order to understand thermospheric/ionospheric disturbances in association with changes in solar activity, observational and modelling efforts have been made by many researchers. Recent satellite observations, e.g., the satellite CHAMP, have revealed mass density variations in the upper thermosphere. The thermospheric temperature, wind, and composition variations have been also investigated with general/global circulation models (GCMs) which include forcings due to the solar wind energy inputs and the lower atmospheric effects. In particular, we have developed a GCM which covers all the atmospheric regions, troposphere, stratosphere, mesosphere, and thermosphere, to describe variations of the thermospheric temperature and density caused by both effects from the lower atmosphere and the magnetosphere. GCM simulations represent global and localized temperature and density structures, which vary from hour to hour, depending on forcings due to the lower atmosphere, solar and geomagnetic activities. This modelling attempt will enable us to describe the thermospheric weather influenced by solar activity in cooperation with ground-based and satellite observations.

One-way to improve organic solar cell efficiency is blending conjugated polymer with a second nanocomposite. We report on blending of freestanding boron- and phosphorous-doped environmental friendly silicon nanocrystals (Si-ncs) with two conjugated polymers i.e. (poly(3-hexylthiophene) (P3HT) and poly[methoxy-ethylexyloxy-phenylenevinilene] (MEH PPV)). The electrochemical etching and pulverization of doped porous silicon films are used for fabrication of photesensitive Si-ncs/polymers blends. Processing of Si-ncs dispersed in polymers allows simple tuning of the Si-ncs concentrations in the blends. The blends with high Si-ncs concentrations are prepared and opto-electric properties are compared and discussed. Both types of polymers containing doped Si-ncs showed a photoconductivity response under illumination AM1.5 at ambient temperature and atmosphere.

By using a high density microwave plasma source, an ultrafast deposition rate over 1000 nm/s has been achieved for polycrystalline silicon (poly-Si) film deposition. We find that crystalline structure of the deposited film evolves along the film growth direction, i.e. large grains in surface region while small grains in the bottom region of the film. Systematic study of the deposition process has been performed as a function of the deposition duration. Based on the observed results, a possible mechanism, the annealing-assisted plasma-enhanced chemical vapor deposition, is proposed to describe the film growth process.

Intrinsic hydrogenated amorphous silicon (a-Si:H) films can yield in outstanding electronic surface passivation of crystalline silicon (c-Si) wafers as utilized in the HIT (heterojunction with intrinsic thin layer) solar cells. We have studied the correlation between the passivation quality and the interface nature between thin amorphous layers and an underlying c-Si substrate for understanding the passivation mechanism. We found that a thin (∼5nm) intrinsic layer is inhomogeneous along the growth direction with the presence of a hydrogen rich layer at the interface and that completely amorphous films result in better passivation quality and device performance than an epitaxial layer. Post annealing improves carrier lifetime for the amorphous layer, whereas the annealing is detrimental for the epitaxial layer. We have also found that the passivation quality of intrinsic a Si:H(i) film deteriorates severely by the presence of a boron-doped a-Si:H(p+) overlayer due to Si-H rupture in the a-Si:H(i) film. Finally, for a passivation layer in the hetero-junction structure, a-Si1−xOx will be demonstrated in comparison with a-Si:H.

The surface states of silicon nanocrystals (Si-ncs) considerably affect quantum confinement effects and may determinate final nanocrystals properties. Colloidally dispersed Si-ncs offer larger freedom for surface modification compared to common plasma enhanced chemical vapor deposition or epitaxial synthesis in a solid matrix. The Si-ncs fabrication and elaboration in water by pulsed laser processing is an attractive alternative for controlling and engineering of nanocrystal surface by environmentally compatible way. We report on the possibility of direct silicon surface ablation and Si-ncs fabrication by nanosecond pulsed laser fragmentation of electrochemically etched Si micrograins and by laser ablation of crystalline silicon target immersed in de-ionized water. Two nanosecond pulsed lasers (Nd:YAG, and excimer KrF) are successfully employed to assure fragmentation and ablation in order to produce silicon nanoparticles. Contrary to the fragmentation process, which is more efficient under Nd:YAG irradiation, the laser ablation by both lasers led to the fabrication of fine and room temperature photoluminescent Si-ncs. The processing that has natural compatibility with the environment and advanced state of fabrication technologies may imply new possibilities and applications.

Back surface reflectors (BSRs) with grating structures have been developed to enhance light trapping in thin-film microcrystalline Si (μc-Si:H) solar cells. As a grating structure, a periodic honeycomb-like dimple pattern with periods of 100 ˜ 450 nm has been fabricated on Al substrates by a self-ordering process using anodic oxidation of Al. A clear diffraction effect by the grating structure has been confirmed on the patterned Al using angle-dependent reflection measurement. From quantum efficiency measurements, we found that the periodically patterned BSR can confine the incident light effectively, especially at longer wavelengths. Nevertheless, short circuit current densities obtained from the patterned BSRs are rather comparable to that obtained from the random textured substrate. For further improvement of the light-trapping effect by the grating structure, it is necessary to realize higher diffraction efficiencies while maintaining high total reflectivity on the BSR structure.

We have demonstrated real-time process control of a-Si:H growth in an a-Si:H/c-Si heterojunction solar cell by spectroscopic ellipsometry (SE). Accurate thickness control of a-Si:H p-i layers with a precision better than ± Å has been realized by this technique. From real-time attenuated total reflection spectroscopy (ATR), we find the formation of a porous interface layer with a maximum SiH2-hydrogen content of 27 at.% at the a-Si:H/c-Si interface, although a rather high conversion efficiency of 14.6 % has been obtained in the solar cell. We found that an optimum i-layer thickness for the a-Si:H/c-Si solar cells is consistent with the thickness at which the a-Si:H i-layer growth reaches a steady state after the H-rich interface-layer formation. We have applied SE further to determine the dielectric functions of In2O3:Sn and ZnO:Ga with different carrier concentrations. From the dielectric function analysis, the effective mass m is extracted. We find linear increases in m as the carrier concentration of In2O3:Sn and ZnO:Ga increases. The validity of our analyses has been confirmed from excellent agreement between carrier concentrations determined by SE and Hall measurements. The construction of the optical database further enabled us to calculate a reflectance spectrum of the a-Si:H/c-Si solar cell accurately.

In order to investigate microcrystalline silicon (μc-Si:H) nucleation from the hydrogenated amorphous silicon (a-Si:H) phase, we performed a H2-plasma treatment of a-Si:H layers deposited at different temperatures. In the H-treatment experiment, the formation process of an infrared peak at ∼1937 cm-1, assigned to SiHn (n=1∼2) complex, is studied, as the SiHn complex is proposed to be a precursor for the μc-Si:H nucleation. With increasing the a-Si:H deposition temperature, the total amount of the SiHn complex formed by the H treatment increased. Nucleation of μc-Si:H under high H2-dilution conditions showed a clear relationship with the SiHn complex formed by the H treatment. The SiHn complex formation process, in terms of strained Si-Si bond breaking by H, is discussed.

We have characterized a-Si:H initial layers for μc-Si:H nucleation by real time spectroscopic ellipsometry (SE) and infrared attenuated total reflection spectroscopy (ATR) to investigate the μc-Si:H formation mechanism. By performing Ar plasma treatment of a-Si:H layers, we confirmed a presence of a 2 monolayer thick sub-surface in a-Si:H layers. In the a-Si:H sub-surface that leads to the μc-Si:H nucleation, an important peak at ∼1937 cm−1 assigned to the SiHn complex was found in the ATR spectra. From H2 plasma treatment experiments, we proposed that this SiHn complex is formed by H insertion into strained Si-Si bonds. The SiHn complex formed in the a-Si:H sub-surface showed a clear relationship with the μc-Si:H nucleation. From these results, we conclude that the μc-Si:H nucleation occurs by the formation of the chemically active and flexible SiHn complexes in the 2 monolayer thick a-Si:H sub-surface.

Studies have been carried out on a-Si:H materials and corresponding solar cells fabricated with and without hydrogen dilution of silane by rf PECVD. The effect of hydrogen dilution on the growth kinetics and microstructures and their dependence on the substrate temperature have been studied. Hydrogen diluted a-Si:H materials and solar cells exhibit improved properties and higher stability to light induced changes. Distinct differences are found in the electron mobility lifetime (μτ) products and subgap absorption over a wide range of generation rates. Striking differences are also found in the kinetics of light induced degradation in both the materials and their corresponding solar cells. Direct correlations are presented between the degradation kinetics of p(a-SiC:H)/i(a-Si:H)/n(μc-Si) solar cells and those of thin film materials constituting the i-layers.

High-quality (ZnS)n(ZnSe)12n and (ZnSe)n(ZnTe)11n (n=1∼4) crystals were grown at a low temperature of 200°C by hydrogen radical-enhanced chemical vapor deposition. From satellite peaks in x-ray diffraction spectra, these periodic structure crystals were confirmed to be grown coherently on substrates, in spite of large lattice mismatches between the grown layers and the substrates (͛=4∼7%). In photoluminescence (PL) spectra of these films, strong band-edge emissions were predominantly observed, resulting from a suppression of deep-level emissions. We found that the PL peak energy of (ZnSe)n(ZnTe)11n shifts systematically to lower energy by 200 meV with changes in the number of ZnSe layers (n), while relatively small shift of 13 meV was observed in (ZnS)n(ZnSe)12n. These discrepancy can be attributed to the difference of band-lineups or chemical natures of constituent atoms in these crystals.