Showing papers by "National Institute of Advanced Industrial Science and Technology published in 2009"
TL;DR: In this article, the authors present an assessment of 33 deltas chosen to represent the world's Deltas and find that in the past decade, 85% of them experienced severe flooding, resulting in the temporary submergence of 260,000 km2.
Abstract: Many of the world's deltas are densely populated and intensively farmed. An assessment of recent publications indicates that the majority of these deltas have been subject to intense flooding over the past decade, and that this threat will grow as global sea-level rises and as the deltas subside. Many of the world's largest deltas are densely populated and heavily farmed. Yet many of their inhabitants are becoming increasingly vulnerable to flooding and conversions of their land to open ocean. The vulnerability is a result of sediment compaction from the removal of oil, gas and water from the delta's underlying sediments, the trapping of sediment in reservoirs upstream and floodplain engineering in combination with rising global sea level. Here we present an assessment of 33 deltas chosen to represent the world's deltas. We find that in the past decade, 85% of the deltas experienced severe flooding, resulting in the temporary submergence of 260,000 km2. We conservatively estimate that the delta surface area vulnerable to flooding could increase by 50% under the current projected values for sea-level rise in the twenty-first century. This figure could increase if the capture of sediment upstream persists and continues to prevent the growth and buffering of the deltas.
1,825 citations
TL;DR: A novel mammalian autophagy factor, Atg13, is reported, which forms a stable approximately 3-MDa protein complex with ULK1 and FIP200, and suggests that mTORC1 suppressesAutophagy through direct regulation of the approximately 3,MDa ULK 1-Atg13-FIP200 complex.
Abstract: Autophagy is an intracellular degradation system, by which cytoplasmic contents are degraded in lysosomes. Autophagy is dynamically induced by nutrient depletion to provide necessary amino acids within cells, thus helping them adapt to starvation. Although it has been suggested that mTOR is a major negative regulator of autophagy, how it controls autophagy has not yet been determined. Here, we report a novel mammalian autophagy factor, Atg13, which forms a stable approximately 3-MDa protein complex with ULK1 and FIP200. Atg13 localizes on the autophagic isolation membrane and is essential for autophagosome formation. In contrast to yeast counterparts, formation of the ULK1-Atg13-FIP200 complex is not altered by nutrient conditions. Importantly, mTORC1 is incorporated into the ULK1-Atg13-FIP200 complex through ULK1 in a nutrient-dependent manner and mTOR phosphorylates ULK1 and Atg13. ULK1 is dephosphorylated by rapamycin treatment or starvation. These data suggest that mTORC1 suppresses autophagy through direct regulation of the approximately 3-MDa ULK1-Atg13-FIP200 complex.
1,754 citations
TL;DR: The dimensional confinement of tin oxide nanoparticles by the surrounding GNS limits the volume expansion upon lithium insertion, and the developed pores between SnO(2) and GNS could be used as buffered spaces during charge/discharge, resulting in the superior cyclic performances.
Abstract: To fabricate nanoporous electrode materials with delaminated structure, the graphene nanosheets (GNS) in the ethylene glycol solution were reassembled in the presence of rutile SnO2 nanoparticles. According to the TEM analysis, the graphene nanosheets are homogeneously distributed between the loosely packed SnO2 nanoparticles in such a way that the nanoporous structure with a large amount of void spaces could be prepared. The obtained SnO2/GNS exhibits a reversible capacity of 810 mAh/g; furthermore, its cycling performance is drastically enhanced in comparison with that of the bare SnO2 nanoparticle. After 30 cycles, the charge capacity of SnO2/GNS still remained 570 mAh/g, that is, about 70% retention of the reversible capacity, while the specific capacity of the bare SnO2 nanoparticle on the first charge was 550 mAh/g, dropping rapidly to 60 mAh/g only after 15 cycles. The dimensional confinement of tin oxide nanoparticles by the surrounding GNS limits the volume expansion upon lithium insertion, and t...
1,630 citations
TL;DR: The manufacture of printable elastic conductors comprising single-walled carbon nanotubes (SWNTs) uniformly dispersed in a fluorinated rubber is described, which is constructed a rubber-like stretchable active-matrix display comprising integrated printed elastic conductor, organic transistors and organic light-emitting diodes.
Abstract: Stretchability will significantly expand the applications scope of electronics, particularly for large-area electronic displays, sensors and actuators. Unlike for conventional devices, stretchable electronics can cover arbitrary surfaces and movable parts. However, a large hurdle is the manufacture of large-area highly stretchable electrical wirings with high conductivity. Here, we describe the manufacture of printable elastic conductors comprising single-walled carbon nanotubes (SWNTs) uniformly dispersed in a fluorinated rubber. Using an ionic liquid and jet-milling, we produce long and fine SWNT bundles that can form well-developed conducting networks in the rubber. Conductivity of more than 100 S cm(-1) and stretchability of more than 100% are obtained. Making full use of this extraordinary conductivity, we constructed a rubber-like stretchable active-matrix display comprising integrated printed elastic conductors, organic transistors and organic light-emitting diodes. The display could be stretched by 30-50% and spread over a hemisphere without any mechanical or electrical damage.
1,616 citations
TL;DR: In this review, microbial and enzymatic biodegradation of plastics and some factors that affect their biodegradability are discussed.
Abstract: Plastic is a broad name given to different polymers with high molecular weight, which can be degraded by various processes. However, considering their abundance in the environment and their specificity in attacking plastics, biodegradation of plastics by microorganisms and enzymes seems to be the most effective process. When plastics are used as substrates for microorganisms, evaluation of their biodegradability should not only be based on their chemical structure, but also on their physical properties (melting point, glass transition temperature, crystallinity, storage modulus etc.). In this review, microbial and enzymatic biodegradation of plastics and some factors that affect their biodegradability are discussed.
1,126 citations
TL;DR: It is found that Pt particles below 0.5 nm in size are formed on GNS, which would acquire the specific electronic structures of Pt, modifying its catalytic activities.
Abstract: Graphene nanosheet (GNS) gives rise to an extraordinary modification to the properties of Pt cluster electrocatalysts supported on it. The Pt/GNS electrocatalyst revealed an unusually high activity for methanol oxidation reaction compared to Pt/carbon black catalyst. The Pt/GNS electrocatalyst also revealed quite a different characteristic for CO oxidation among the measured catalyst samples. It is found that Pt particles below 0.5 nm in size are formed on GNS, which would acquire the specific electronic structures of Pt, modifying its catalytic activities.
1,028 citations
TL;DR: A freestanding single layer of hexagonal boron nitride (h-BN) has been successfully fabricated by controlled energetic electron irradiation through a layer-by-layer sputtering process and the dominating zigzag-type edges are proved to be nitrogen terminated.
Abstract: A freestanding single layer of hexagonal boron nitride (h-BN) has been successfully fabricated by controlled energetic electron irradiation through a layer-by-layer sputtering process. We have successfully resolved atomic defects in h-BN with triangle shapes by means of an aberration corrected high-resolution transmission electron microscopy with exit-wave reconstruction. Boron monovacancies are found to be preferably formed and the dominating zigzag-type edges are proved to be nitrogen terminated.
1,009 citations
TL;DR: The present article deals with the synthetic technologies leading to organic carbonates using CO(2) as a raw material.
941 citations
TL;DR: The results of numerous studies show that LPO, and probably oxidative stress in general, may exert both deleterious and beneficial effects in vivo, and it appears difficult to regulate the formation of free radical-mediated LPO products.
867 citations
TL;DR: A catalyst, Au@ZIF-8, represents the first example of an active catalyst in CO oxidation by using a MOF as a novel support for noble metal NPs.
Abstract: Gold nanoparticles (NPs) were deposited to a zeolite-type metal-organic framework (MOF) by a simple solid grinding method. A catalyst, Au@ZIF-8, represents the first example of an active catalyst in CO oxidation by using a MOF as a novel support for noble metal NPs. The catalytic activity for CO oxidation is improved along with increasing Au loadings, and the highest catalytic activity is obtained for 5.0 wt % Au@ZIF-8, which presents half conversion of CO at approximately 170 degrees C. Gold NPs are close to being monodisperse and have no aggregation during catalytic reaction, and the catalytic activity is reproducible.
754 citations
TL;DR: In this article, Nitrogen-enriched nonporous carbon materials derived from melamine-mica composites are subjected to ammonia treatment to further increase the nitrogen content and are tested as electrodes for supercapacitors, and in acidic or basic electrolytes, the gravimetric capacitance of treat samples is three times higher than that of untreated samples.
Abstract: Nitrogen-enriched nonporous carbon materials derived from melamine-mica composites are subjected to ammonia treatment to further increase the nitrogen content. For samples preoxidized prior to the ammonia treatment, the nitrogen content is doubled and is mainly incorporated in pyrol-like groups. The materials are tested as electrodes for supercapacitors, and in acidic or basic electrolytes, the gravimetric capacitance of treat samples is three times higher than that of untreated samples. This represents a tenfold increase of the capacitance per surface area (3300 mu F cm(-2)) in basic electrolyte. Due to the small volume of the carbon materials, high volumetric capacitances are achieved in various electrolytic systems: 280 F cm(-3) in KOH, 152 F CM(-3) in H(2)SO(4), and 92 F cm(-3) in tetraethylammonium tetrafluoroborate/propylene carbonate.
TL;DR: Among all known materials, it is found that a forest of vertically aligned single-walled carbon nanotubes behaves most similarly to a black body, a theoretical material that absorbs all incident light.
Abstract: Among all known materials, we found that a forest of vertically aligned single-walled carbon nanotubes behaves most similarly to a black body, a theoretical material that absorbs all incident light. A requirement for an object to behave as a black body is to perfectly absorb light of all wavelengths. This important feature has not been observed for real materials because materials intrinsically have specific absorption bands because of their structure and composition. We found a material that can absorb light almost perfectly across a very wide spectral range (0.2–200 μm). We attribute this black body behavior to stem from the sparseness and imperfect alignment of the vertical single-walled carbon nanotubes.
TL;DR: This communication reports a hightemperature piezoelectric material that exhibits a good balance between high maximum use temperature and large piez Zoelectricity, achieved by the combination of the discovery of a phase transition in scandium aluminum nitride (ScxAl1 xN) alloy thin films and the use of dual co-sputtering, which leads to nonequilibrium alloy thin Films.
Abstract: Adv. Mater. 2009, 21, 593–596 2009 WILEY-VCH Verlag Gm The industrial demand for higher-temperature piezoelectric sensors is drastically increasing, for the control of automobile, aircraft, and turbine engines and the monitoring of furnace and reactor systems, because environmental problems, such as carbon dioxide (CO2) and nitrogen oxide (NOx) reduction, are becoming more globally serious. The sensors are also desirable for health monitoring coal-fired electric-generation plants and nuclear plants. It is generally known that piezoelectric materials with a higher Curie temperature possess a lower piezoelectric coefficient. Furthermore, the results of a study (Fig. 1) of the relationship between maximum use temperature and piezoelectric coefficient d33 shows that the piezoelectric materials with a higher maximum use temperature possess a lower piezoelectric coefficient d33. [3–9] For example, the Curie temperature and piezoelectric coefficient d33 of lead zirconium titanate (PZT), which is widely used in many electronic devices, are 250 8C and 410 pCN , respectively. The maximum use temperature and d33 of aluminum nitride (AlN), which is a typical hightemperature piezoelectric material, are 1150 8C and 5.5 pCN . It is difficult to achieve a good balance between high maximum use temperature and large piezoelectricity in a material, and no effective piezoelectric materials with these characteristics have yet been found. In this communication, we report a hightemperature piezoelectric material that exhibits a good balance between high maximum use temperature and large piezoelectricity. This was achieved by the combination of the discovery of a phase transition in scandium aluminum nitride (ScxAl1 xN) alloy thin films and the use of dual co-sputtering, which leads to nonequilibrium alloy thin films. Sc0.43Al0.57N alloys exhibit a large piezoelectric coefficient d33 of 27.6 pCN , which is at least 500% larger than AlN. The large piezoelectric coefficient d33 is the highest piezoelectric response among the tetrahedrally bonded semiconductors, despite the fact that the crystal structure of scandium nitride (ScN) is rock-salt (nonpolar). Moreover, the large piezoelectricity is not changed by annealing at 500 8C for 56 h under vacuum. This work demonstrates the new route to design of this high-temperature piezoelectric material. ScN has a rock-salt structure (nonpolar). However, Takeuchi reported the existence of a (meta)stable wurtzite structure in ScN, and the possible fabrication of Sc-IIIA-N nitrides by firstprinciples calculations. Farrer et al. predicted that the wurtzite structure is unstable in ScN, and that the hexagonal structure is (meta)stable in ScN, unlike the wurtzite structure. The piezoelectric responses of hexagonal ScxGa1 xN and ScxIn1 xN alloys can be enhanced by an isostructural phase transition (from wurtzite to layered hexagonal). However, the piezoelectric responses and Curie temperatures of the nitride alloys have not yet been confirmed by experiments. AlN, GaN, and InN are IIIA nitrides and have a wurtzite structure (polar). In particular, the thermal stability and piezoelectricity of AlN are the highest among the IIIA nitrides. AlN is a piezoelectric material compatible with the Complementary metal–oxide– semiconductor (CMOS) manufacturing process, and is a promising material for integrated sensors/actuators on silicon substrates. Wurtzite and rocksalt structures have rather different lattice forms and unit sizes. The formation of
TL;DR: Electron diffraction shows that on average the underlying carbon lattice maintains the order and lattice-spacings of graphene; a structure that is clearly resolved in 80 kV aberration-corrected atomic resolution TEM images.
Abstract: We report on the structural analysis of graphene oxide (GO) by transmission electron microscopy (TEM). Electron diffraction shows that on average the underlying carbon lattice maintains the order and lattice-spacings of graphene; a structure that is clearly resolved in 80 kV aberration-corrected atomic resolution TEM images. These results also reveal that single GO sheets are highly electron transparent and stable in the electron beam, and hence ideal support films for the study of nanoparticles and macromolecules by TEM. We demonstrate this through the structural analysis of physiological ferritin, an iron-storage protein.
TL;DR: Li et al. as mentioned in this paper have successfully synthesized a high-purity polycrystalline sample of tetragonal Li7La3Zr2O12, which is composed of two types of dodecahedral LaO8 and octahedral ZrO6.
TL;DR: A previously unknown Wnt-mediated regulatory mechanism that simultaneously coordinates activation of NeuroD1 and LINE-1 is described, which is important for adult neurogenesis and survival of neuronal progenitors.
Abstract: In adult hippocampus, new neurons are continuously generated from neural stem cells (NSCs), but the molecular mechanisms regulating adult neurogenesis remain elusive. We found that Wnt signaling, together with the removal of Sox2, triggered the expression of NeuroD1 in mice. This transcriptional regulatory mechanism was dependent on a DNA element containing overlapping Sox2 and T-cell factor/lymphoid enhancer factor (TCF/LEF)-binding sites (Sox/LEF) in the promoter. Notably, Sox/LEF sites were also found in long interspersed nuclear element 1 (LINE-1) elements, consistent with their critical roles in the transition of NSCs to proliferating neuronal progenitors. Our results describe a previously unknown Wnt-mediated regulatory mechanism that simultaneously coordinates activation of NeuroD1 and LINE-1, which is important for adult neurogenesis and survival of neuronal progenitors. Moreover, the discovery that LINE-1 retro-elements embedded in the mammalian genome can function as bi-directional promoters suggests that Sox/LEF regulatory sites may represent a general mechanism, at least in part, for relaying environmental signals to other nearby loci to promote adult hippocampal neurogenesis.
TL;DR: The method reported here is promising to investigate all-carbon-based devices with the carbon atomic chains as the conducting channel, which can be regarded as the ultimate basic component of molecular devices.
Abstract: Stable and rigid carbon atomic chains were experimentally realized by removing carbon atoms row by row from graphene through the controlled energetic electron irradiation inside a transmission electron microscope. The observed structural dynamics of carbon atomic chains such as formation, migration, and breakage were well explained by density-functional theory calculations. The method we reported here is promising to investigate all-carbon-based devices with the carbon atomic chains as the conducting channel, which can be regarded as the ultimate basic component of molecular devices.
TL;DR: A series of tilting experiments proves that the zigzag and armchair edges are mostly closed between adjacent graphene layers, and the number of dangling bonds is therefore minimized.
Abstract: Edge structures of thermally treated graphite have been studied by means of atomically resolved high-resolution TEM. The method for the determination of a monolayer or more than one layer graphene sheets is established. A series of tilting experiments proves that the zigzag and armchair edges are mostly closed between adjacent graphene layers, and the number of dangling bonds is therefore minimized. Surprisingly bilayer graphene often exhibits AA stacking and is very hard to distinguish from a single graphene layer. Open edge structures with carbon dangling bonds can be found only in a local area where the closed (folding) edge is partially broken.
University of Malaya1, Central Food Technological Research Institute2, Thailand National Science and Technology Development Agency3, Mahidol University4, Korea Research Institute of Bioscience and Biotechnology5, University of the Philippines6, Academia Sinica7, Agency for Science, Technology and Research8, Peking Union Medical College9, National Institute of Advanced Industrial Science and Technology10, Universiti Sains Malaysia11, Chinese National Human Genome Center12, Tokai University13, Fudan University14, Chiang Mai University15, Thermo Fisher Scientific16, Soongsil University17, Eulji University18, University of Tokyo19, National University of Singapore20, Indian Statistical Institute21, Eijkman Institute for Molecular Biology22, Nanyang Technological University23, University of the Ryukyus24, Health Sciences University of Hokkaido25, Monash University Malaysia Campus26, National Institutes of Health27
TL;DR: The results suggest that there may have been a single major migration of people into Asia and a subsequent south-to-north migration across the continent, and that genetic ancestry is strongly correlated with linguistic affiliations as well as geography.
Abstract: Asia harbors substantial cultural and linguistic diversity, but the geographic structure of genetic variation across the continent remains enigmatic. Here we report a large-scale survey of autosomal variation from a broad geographic sample of Asian human populations. Our results show that genetic ancestry is strongly correlated with linguistic affiliations as well as geography. Most populations show relatedness within ethnic/linguistic groups, despite prevalent gene flow among populations. More than 90% of East Asian (EA) haplotypes could be found in either Southeast Asian (SEA) or Central-South Asian (CSA) populations and show clinal structure with haplotype diversity decreasing from south to north. Furthermore, 50% of EA haplotypes were found in SEA only and 5% were found in CSA only, indicating that SEA was a major geographic source of EA populations.
TL;DR: A model for nuclear paraspeckle body organization is postulate where specific ncRNAs and RNA-binding proteins cooperate to maintain and, presumably, establish the structure.
Abstract: Recent transcriptome analyses have shown that thousands of noncoding RNAs (ncRNAs) are transcribed from mammalian genomes. Although the number of functionally annotated ncRNAs is still limited, they are known to be frequently retained in the nucleus, where they coordinate regulatory networks of gene expression. Some subnuclear organelles or nuclear bodies include RNA species whose identity and structural roles are largely unknown. We identified 2 abundant overlapping ncRNAs, MENe and MENβ (MENe/β), which are transcribed from the corresponding site in the multiple endocrine neoplasia (MEN) I locus and which localize to nuclear paraspeckles. This finding raises the intriguing possibility that MENe/β are involved in paraspeckle organization, because paraspeckles are, reportedly, RNase-sensitive structures. Successful removal of MENe/β by a refined knockdown method resulted in paraspeckle disintegration. Furthermore, the reassembly of paraspeckles disassembled by transcriptional arrest appeared to be unsuccessful in the absence of MENe/β. RNA interference and immunoprecipitation further revealed that the paraspeckle proteins p54/nrb and PSF selectively associate with and stabilize the longer MENβ, thereby contributing to the organization of the paraspeckle structure. The paraspeckle protein PSP1 is not directly involved in either MENe/β stabilization or paraspeckle organization. We postulate a model for nuclear paraspeckle body organization where specific ncRNAs and RNA-binding proteins cooperate to maintain and, presumably, establish the structure.
TL;DR: Nishio et al. as discussed by the authors survey recent results relevant to the CH/π hydrogen bond: crystal conformation, packing and host/guest chemistry, and summarize the results obtained by crystallographic database (CSD and PDB) analyses.
Abstract: This treatise is an update to a preceding highlight (CH/π hydrogen bonds in crystals) published in this journal 5 years ago (M. Nishio, CrystEngComm, 2004, 6, 130–156). After the introductory part (sections 1 and 2), we survey recent results (mostly since 2004) relevant to the CH/π hydrogen bond: crystal conformation, packing and host/guest chemistry (section 3). Section 4 summarizes the results obtained by crystallographic database (CSD and PDB) analyses. In section 5, several topics in related fields (selectivity in organic reactions, surface chemistry, structural biology, drug design and high-level ab initio calculations of protein/substrate complexes and natural organic compounds) are introduced, and in the final part we comment on the prospects of this emerging field of chemistry.
TL;DR: These single crystalline spinel LiMn2O4 nanowires show high thermal stability because the nanowire structure is maintained after heating to 800 degrees C for 12 h and excellent performance at high rate charge-discharge, such as 20 A/g, with both a relative flat charge- discharge plateau and excellent cycle stability.
Abstract: How to improve the specific power density of the rechargeable lithium ion battery has recently become one of the most attractive topics of both scientific and industrial interests. The spinel LiMn2O4 is the most promising candidate as a cathode material because of its low cost and nontoxicity compared with commercial LiCoO2. Moreover, nanostructured electrodes have been widely investigated to satisfy such industrial needs. However, the high-temperature sintering process, which is necessary for high-performance cathode materials based on high-quality crystals, leads the large grain size and aggregation of the nanoparticles which gives poor lithium ion battery performance. So there is still a challenge to synthesize a high-quality single-crystal nanostructured electrode. Among all of the nanostructures, a single crystalline nanowire is the most attractive morphology because the nonwoven fabric morphology constructed by the single crystalline nanowire suppresses the aggregation and grain growth at high tempe...
TL;DR: In this review, recent progress with regard to studies using several promising approaches such as host strain selection and adaptation to obtain further improved xylose-utilizing S. cerevisiae strains are addressed.
Abstract: Bioethanol production from xylose is important for utilization of lignocellulosic biomass as raw materials. The research on yeast conversion of xylose to ethanol has been intensively studied especially for genetically engineered Saccharomyces cerevisiae during the last 20 years. S. cerevisiae, which is a very safe microorganism that plays a traditional and major role in industrial bioethanol production, has several advantages due to its high ethanol productivity, as well as its high ethanol and inhibitor tolerance. However, this yeast cannot ferment xylose, which is the dominant pentose sugar in hydrolysates of lignocellulosic biomass. A number of different strategies have been applied to engineer yeasts capable of efficiently producing ethanol from xylose, including the introduction of initial xylose metabolism and xylose transport, changing the intracellular redox balance, and overexpression of xylulokinase and pentose phosphate pathways. In this review, recent progress with regard to these studies is discussed, focusing particularly on xylose-fermenting strains of S. cerevisiae. Recent studies using several promising approaches such as host strain selection and adaptation to obtain further improved xylose-utilizing S. cerevisiae are also addressed.
TL;DR: Data suggest that Atg101 is a novel Atg protein that functions together with ULK, Atg13 and FIP200, and is important for the stability and basal phosphorylation of AtG13 and ULK1.
Abstract: Autophagy is a major route by which cytoplasmic contents are delivered to the lysosome for degradation. Many autophagy-related (ATG) genes have been identified in yeast. Although most of them are conserved in human, the molecular composition of the Atg1 complex appears to differ between yeast and mammals. In yeast, Atg1 forms a complex with Atg11, Atg13, Atg17, Atg29 and Atg31, whereas mammalian Atg1 (ULK1/2) interacts with Atg13 and FIP200. Here, we identify a novel mammalian Atg13 binding protein, named Atg101. Atg101 shows no homology with other Atg proteins, and is conserved in various eukaryotes, but not in Saccharomyces cerevisiae. Atg101 associates with the ULK-Atg13-FIP200 complex, most likely through direct interaction with Atg13. In Atg13 siRNA-treated cells, Atg101 is present solely as a monomer. Interaction between Atg101 and the ULK-Atg13-FIP200 complex is stable, and is not regulated by nutrient conditions. GFP-Atg101 localizes to the isolation membrane/phagophore. GFP-LC3 dot formation is suppressed and endogenous LC3-I accumulates in Atg101 siRNA-treated cells, suggesting that Atg101 is a critical factor for autophagy. Furthermore, Atg101 is important for the stability and basal phosphorylation of Atg13 and ULK1. These data suggest that Atg101 is a novel Atg protein that functions together with ULK, Atg13 and FIP200.
TL;DR: It was shown that the electrochemical performance of the cell was extensively improved when the size of constituent particles was reduced so as to yield a highly porous microstructure, which led to better cell performance for the cell with higher anode porosity.
Abstract: We report a correlation between the microstructure of the anode electrode of a solid oxide fuel cell (SOFC) and its electrochemical performance for a tubular design. It was shown that the electrochemical performance of the cell was extensively improved when the size of constituent particles was reduced so as to yield a highly porous microstructure. The SOFC had a power density of greater than 1 watt per square centimeter at an operating temperature as low as 600°C with a conventional zirconia-based electrolyte, a nickel cermet anode, and a lanthanum ferrite perovskite cathode material. The effect of the hydrogen fuel flow rate (linear velocity) was also examined for the optimization of operating conditions. Higher linear fuel velocity led to better cell performance for the cell with higher anode porosity. A zirconia-based cell could be used for a low-temperature SOFC system under 600°C just by optimizing the microstructure of the anode electrode and operating conditions.
TL;DR: In gonadal somatic cells, tj gives rise simultaneously to two different molecules: the TJ protein, which activates Piwi expression, and piRNAs, which define the Piwi targets for silencing.
Abstract: PIWI-interacting RNAs (piRNAs) silence retrotransposons in Drosophila germ lines by associating with the PIWI proteins Argonaute 3 (AGO3), Aubergine (Aub) and Piwi. piRNAs in Drosophila are produced from intergenic repetitive genes and piRNA clusters by two systems: the primary processing pathway and the amplification loop. The amplification loop occurs in a Dicer-independent, PIWI-Slicer-dependent manner. However, primary piRNA processing remains elusive. Here we analysed piRNA processing in a Drosophila ovarian somatic cell line where Piwi, but not Aub or AGO3, is expressed; thus, only the primary piRNAs exist. In addition to flamenco, a Piwi-specific piRNA cluster, traffic jam (tj), a large Maf gene, was determined as a new piRNA cluster. piRNAs arising from tj correspond to the untranslated regions of tj messenger RNA and are sense-oriented. piRNA loading on to Piwi may occur in the cytoplasm. zucchini, a gene encoding a putative cytoplasmic nuclease, is required for tj-derived piRNA production. In tj and piwi mutant ovaries, somatic cells fail to intermingle with germ cells and Fasciclin III is overexpressed. Loss of tj abolishes Piwi expression in gonadal somatic cells. Thus, in gonadal somatic cells, tj gives rise simultaneously to two different molecules: the TJ protein, which activates Piwi expression, and piRNAs, which define the Piwi targets for silencing.
TL;DR: It is shown that molecular rotator motion is controllable using an external electric field and demonstrated how such molecular rotators can be used as polarization rotation units in ferroelectric molecules.
Abstract: Molecular rotation has attracted much attention with respect to the development of artificial molecular motors, in an attempt to mimic the intelligent and useful functions of biological molecular motors. Random motion of molecular rotators—for example the 180∘ flip-flop motion of a rotatory unit—causes a rotation of the local structure. Here, we show that such motion is controllable using an external electric field and demonstrate how such molecular rotators can be used as polarization rotation units in ferroelectric molecules. In particular, m-fluoroanilinium forms a hydrogen-bonding assembly with dibenzo[18]crown-6, which was introduced as the counter cation of [Ni(dmit)2]− anions (dmit2−=2-thioxo-1,3-dithiole-4,5-dithiolate). The supramolecular rotator of m-fluoroanilinium exhibited dipole rotation by the application of an electric field, and the crystal showed a ferroelectric transition at 348 K. These findings will open up new strategies for ferroelectric molecules where a chemically designed dipole unit enables control of the nature of the ferroelectric transition temperature. Molecular rotors have seen considerable interest as functional molecules on surfaces or for applications as memory devices. However, it is now shown that molecular rotation may also be used to induce ferroelectricity in a molecule.
TL;DR: This study shows that miR-140 has a chondrocyte differentiation-related expression pattern that may contribute to the abnormal gene expression pattern characteristic of OA.
Abstract: Objective
MicroRNA (miRNA) are a class of noncoding small RNAs that act as negative regulators of gene expression. MiRNA exhibit tissue-specific expression patterns, and changes in their expression may contribute to pathogenesis. The objectives of this study were to identify miRNA expressed in articular chondrocytes, to determine changes in osteoarthritic (OA) cartilage, and to address the function of miRNA-140 (miR-140).
Methods
To identify miRNA specifically expressed in chondrocytes, we performed gene expression profiling using miRNA microarrays and quantitative polymerase chain reaction with human articular chondrocytes compared with human mesenchymal stem cells (MSCs). The expression pattern of miR-140 was monitored during chondrogenic differentiation of human MSCs in pellet cultures and in human articular cartilage from normal and OA knee joints. We tested the effects of interleukin-1β (IL-1β) on miR-140 expression. Double-stranded miR-140 (ds–miR-140) was transfected into chondrocytes to analyze changes in the expression of genes associated with OA.
Results
Microarray analysis showed that miR-140 had the largest difference in expression between chondrocytes and MSCs. During chondrogenesis, miR-140 expression in MSC cultures increased in parallel with the expression of SOX9 and COL2A1. Normal human articular cartilage expressed miR-140, and this expression was significantly reduced in OA tissue. In vitro treatment of chondrocytes with IL-1β suppressed miR-140 expression. Transfection of chondrocytes with ds–miR-140 down-regulated IL-1β–induced ADAMTS5 expression and rescued the IL-1β–dependent repression of AGGRECAN gene expression.
Conclusion
This study shows that miR-140 has a chondrocyte differentiation–related expression pattern. The reduction in miR-140 expression in OA cartilage and in response to IL-1β may contribute to the abnormal gene expression pattern characteristic of OA.
TL;DR: Results indicate that Mincle is the first specific receptor for Malassezia species to be reported and plays a crucial role in immune responses to this fungus.
Abstract: Mincle (also called as Clec4e and Clecsf9) is a C-type lectin receptor expressed in activated phagocytes. Recently, we have demonstrated that Mincle is an FcRγ-associated activating receptor that senses damaged cells. To search an exogenous ligand(s), we screened pathogenic fungi using cell line expressing Mincle, FcRγ, and NFAT-GFP reporter. We found that Mincle specifically recognizes the Malassezia species among 50 different fungal species tested. Malassezia is a pathogenic fungus that causes skin diseases, such as tinea versicolor and atopic dermatitis, and fatal sepsis. However, the specific receptor on host cells has not been identified. Mutation of the putative mannose-binding motif within C-type lectin domain of Mincle abrogated Malassezia recognition. Analyses of glycoconjugate microarray revealed that Mincle selectively binds to α-mannose but not mannan. Thus, Mincle may recognize specific geometry of α-mannosyl residues on Malassezia species and use this to distinguish them from other fungi. Malassezia activated macrophages to produce inflammatory cytokines/chemokines. To elucidate the physiological function of Mincle, Mincle-deficient mice were established. Malassezia-induced cytokine/chemokine production by macrophages from Mincle−/− mice was significantly impaired. In vivo inflammatory responses against Malassezia was also impaired in Mincle−/− mice. These results indicate that Mincle is the first specific receptor for Malassezia species to be reported and plays a crucial role in immune responses to this fungus.
TL;DR: Using real-time polymerase chain reaction (PCR) to measure the expression of 188 miRNAs in liver tissues obtained from 12 patients with hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) and 14 patients with HCV-related HCC, including background liver tissues from nine patients.