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The Sanakham gold deposit is a newly discovered gold deposit in the Luang Prabang (Laos)–Loei (Thailand) metallogenic belt. It consists of a series of auriferous quartz-sulfide veins, which is distinguished from the regional known porphyry-related skarn and epithermal gold deposits. There are four mineralization stages identified in Sanakham, with native gold grains mainly occurring in stages II and III. Evolution of ore-forming fluids and gold deposition mechanisms in Sanakham are discussed based on fluid inclusion petrography, microthermometry, and Laser Raman spectroscopy. The original ore-forming fluids belong to a medium-high temperature (>345 °C) CH4-rich CH4–CO2–NaCl–H2O system. In stages II and III, the ore fluids evolve into a NaCl–H2O–CO2 ± CH4 system characterized by medium temperature (~300 °C), medium salinity (~10 wt% NaCl eq.), and CO2-rich (~10% mol). They might finally evolve into a NaCl–H2O system with temperature decreasing and salinity increasing in stage IV. Two fluid immiscibility processes occurred in stages II and III, which created high-CH4 & low-CO2 and low-CH4 & high-CO2 end-members, and CO2-poor and CO2-rich endmembers, respectively. Gold-deposition events are suggested to be associated with the fluid immiscibility processes, with P–T conditions and depth of 236–65 MPa, 337–272 °C, and 8.7–6.5 km, respectively.

The whitefly Bemisia tabaci is a group of small sap-sucking insects, which is now recognized as a cryptic species complex containing at least 35 species. During the last 30 years, the Middle East Asia Minor 1 (MEAM1) and Mediterranean (MED) species of the complex have invaded many countries worldwide with the import and export trade. With the exception of direct feeding, whiteflies harm plants mainly by transmitting plant viruses, causing huge damage to crops, vegetables and ornamental plants worldwide. Tomato yellow leaf curl viruses, cassava mosaic viruses, cotton leaf curl viruses, and tomato chlorosis virus are all transmitted by B. tabaci , and the prevalence of these viral diseases is closely related to the outbreak of these whiteflies. Currently, more than 400 species of plant viruses in five genera, i.e. Begomovirus , Crinivirus , Torradovirus , Ipomovirus and Carlavirus , are transmitted by whiteflies. Among them, begomoviruses are single-stranded DNA viruses and are exclusively transmitted by whiteflies in a persistent-circulative manner. All the others are single-stranded RNA viruses and are transmitted in a semi-persistent or non-persistent manner. Here, we summarize the interactions between B. tabaci and the plant viruses they transmit, particularly recent advances in the understanding of the molecular mechanisms underlying whitefly transmission of plant viruses. There are multiple barriers during the circulative transmission of begomoviruses within the whitefly, including the midgut barrier, hemolymph barrier, salivary gland barrier and transovarial transmission barrier. Passage of viruses through these barriers requires specific interactions between virus and whitefly components. The ability of a virus to cross the barriers within different cryptic species of B. tabaci can lead to differential transmission efficiencies. Moreover, the whitefly immune systems, such as the autophagy pathway and anti-microbial peptides, have been proved to play important roles in suppressing virus infection in B. tabaci . In addition, some whitefly and endosymbiont proteins have been identified that participate in virus circulation within whitefly, which has greatly improved our understanding of this process. However, whether begomoviruses replicate in their whitefly vector is still controversial, and further investigation is urgently needed. We also reviewed the information on the differential transmission efficiency of whitefly-transmitted RNA viruses by different species of whiteflies. However, except the verified critical role of the minor coat protein of criniviruses in virion retention and transmission, the key factors that affect the transmission of these whitefly-transmitted RNA viruses remain largely unknown. A detailed knowledge of the mechanisms underlying plant virus transmission by its whitefly vector can lead to new strategies to combat virus spread in the field. Recent advances in the sequencing of insect genomes, reverse genetic systems and genome editing technologies, such as the CRISPR/Cas9 system, may help us to further reveal the mechanisms of virus transmission and to design novel strategies that interfere with virus transmission.

Despite the presence of a large area of andesite in the Sayaburi Province of Laos, it has received very little attention. Based on a combination of detailed field investigations, geochronology and geochemical analysis, this study aims to explore the geochemical, Sr-Nd isotopic, and source rock characteristics, as well as the genesis and tectonic setting of the andesite in this region. In the Sayaburi Province, the andesite zircon U-Pb age is (241.2±1.2) Ma. The andesite rock is classified in the metaluminous-weak peraluminous calc-alkaline series. The light rare-earth elements (LREEs) are enriched and characterized by clear fractionation, whereas heavy rare-earth elements (HREEs) are relatively depleted and have no signs of fractionation. The average δEu is 0.96 with weak-or-no Eu anomalies. It is enriched in large ion lithophile elements such as Rb and K, while depleted in high field-strength elements such as Nb, Ta, P and Ti. For andesites in the Sayaburi Province, the (87Rb/86Sr)t value ranges in 0.702849–0.704687, the eNd(t) value is between 3.53 and 4.77, the tDM(t) value ranges in 633–835 Ma, and the tDM2(t) ranges in 625–724 Ma. The results based on the synthesis of petrology, geochemistry, and regional tectonic background studies show that 1) the andesitic magma source in the study area is an enriched mantle, which is modified by subduction zone fluids; 2) the geotectonic background environment of the andesite in Sayaburi area is the continental island arc environment and related to the tectonic evolution of Jinghong-Nan-Uttaradit back-arc basin, which reflects that the magmatic source is enriched with a mantle wedge component modified by a subduction zone fluid (or melt).

A core-shell composite consisting of polypyrrole (PPy) nanofibers and TiO 2 was synthesized by using PPy nanofibers as the core and TiO 2 as the shell. The TiO 2 @PPy composite substrate was doped with Pd nanoparticles via chemical reduction. The resulting Pd–TiO 2 @PPy nanocomposite was characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and Brunauer–Emmett–Teller (BET) adsorption analysis before it was utilized to fabricate a hydrogen sensor. Compared with sensors based on TiO 2 @PPy or PPy, the Pd–TiO 2 @PPy sensor was highly sensitive and selective to hydrogen gas, exhibiting a fast response time in air at room temperature. The Pd–TiO 2 @PPy-based sensor exhibited a sensitivity of 8.1% toward 1 vol% of H 2 gas, which is much larger than the sensitivities of sensors based on only TiO 2 @PPy and PPy nanofibers. The excellent reproducibility, stability and selectivity of the Pd–TiO 2 @PPy nanocomposite make it a high potential candidate for hydrogen sensors.

The Phapon gold deposit is located in the northern Laos and the northern segments of the Luang Prabang&ndash, Loei metallogenic belt. The lode-gold orebodies consist of auriferous calcite veins in the middle, and the surrounding siderite alteration and hematite alteration zones in red color. This deposit is hosted in Lower Permian limestone and controlled by a NE-trending ductile&ndash, brittle fault system, and it is characterized by the wallrock alteration of carbonatization and lack of quartz and metal sulfides. The hydrothermal calcite from auriferous calcite veins and red alteration zone, as well as the wall rocks of limestone and sandstone were selected for rare earth elements (REE) and C&ndash, O isotope analyses. The two types of calcite and limestone have generally consistent REE patterns and &delta, Eu and &delta, Ce values, which are completely different from those of sandstone. Calcites from the auriferous vein show slight light rare earth elements (LREE)-depleted patterns and higher Tb/La and Sm/Nd ratios than the ones from the red alteration zone with slight LREE-enriched patterns. These values indicate that the calcites from the auriferous veins and the red alteration zones are products of homologous fluids, but the former ones are generally likely to form later than the latter ones. The hydrothermal calcites have C&ndash, O isotope compositions within the range of marine carbonate, and markedly different from the magmatic or mantle reservoir values. Taking the Y/Ho&ndash, La/Ho and Tb/Ca&ndash, Tb/La variations into consideration, we believe the hydrothermal calcites could be formed from remobilization and recrystallization of the ore-hosted limestone, and the fluid-wallrock interaction played a major role in the gold mineralization in Phapon. In combination with the regional and local geology, the ore-forming process is suspected to be primarily associated with dehydration and decarbonisation of the Lower Permian limestone and Middle&ndash, Upper Triassic sandstones. The Phapon gold deposit could have been formed during the Late Triassic&ndash, Jurassic regional dynamic metamorphism driven by Indochina&ndash, Sibumasu post-collisional magmatism. A number of features in Phapon are similar to epizonal orogenic deposit, but it is still a unique calcite vein type gold deposit in the Luang Prabang-Loei metallogenic belt.

Dehydrogenation processes of α- and γ-AlH3 were investigated by in situ transmission electron microscopy observations. The relationship between Al2O3 thickness and dehydrogenation kinetics was also clarified. The initial shape of α-AlH3 particle was cubic and that of γ-AlH3 particle was rod-shaped. The process of γ-AlH3 was quite similar with α-AlH3. The precipitation and growth of Al was observed in both processes. The dehydrogenation kinetics did not depend on Al2O3 thickness. It was found that milling effect on the dehydrogenation kinetics was larger than doping effect. The dehydrogenation process was discussed in terms of both microscopic and kinetic studies.

Electrode processes in solid oxide fuel cells are intensively studied to increase the system efficiency to compete with that of the state-of-the-art LNG-fueled combined cycle thermal power plant. Because the electrode performance depends both on electrode materials and microstructure, we are obliged to breakdown the complexity of phenomena in the porous electrode into elementary processes by best utilizing both the advanced measurement and the simulation techniques. Closely examining the efforts in literature [1-7], we have taken the combined top-down and bottom-up approach. The most difficult issue has lied on the meso-scale modeling, which typically is based on microkinetic modeling [5-8]. To guarantee the predictivity of the modeling, it is inevitable to realize the simulation without arbitrary fitting parameters that are not necessarily based on realistic physics. For this purpose, we first exhaustively summarized literature data followed by the careful examinations. Next, we have made exhaustive simulations assuming different combinations of parameters in literature. Finally, we obtained a set of parameters that matches with experimental observations within reasonable differences. The details together with the results of top-down and bottom up simulations will be introduced together with future perspectives. Acknowledgements The activities of INAMORI Frontier Research Center is supported by Kyocera Co. Ltd. The activities of Advanced Automotive Research Collaborative Laboratory in Hiroshima University are supported by Mazda Corporation. The part of the research is supported by CREST, Japan Science and Technology Agency. References [1] J. Mizusaki, H. Tagawa, T. Saito, T. Yamamura, K. Kamitani, K. Hirano, S. Ehara, T. Takagi, T. Hikita, M. Ippommatsu, S. Nakagawa, K. Hashimoto, Solid State Ionics, 70/71, 52 (1994) [2] W. Yao and E. Croiset, Can. J. Chem. Eng., 93, 2157 (2015) [3] A. Bieberle, L. P. Meier, L. J. Gauckler, J. Electrochem. Soc., 148, A646 (2001) [4] A. Utz, H. Störmer, A. Leonide, A. Weber, E. Ivers-Tiffée, J. Electrochem. Soc., 157 B920 (2010) [5] W. G. Bessler, S. Gewies, M. Vogler, Electrochim. Acta, 53, 1782 (2007) [6] W. G. Bessler, Solid State Ionics, 176, 997 (2005) [7] M. Vogler, A. Bieberle-Hütter, L. Gauckler, J. Warnatz, and W. G. Bessler, J. Electrochem. Soc., 156, B663 (2009) [8] H. Kohno, S. Liu, T. Ogura, T. Ishimoto, D. S. Monder, K. Karan, M. Koyama, ECS Trans., 57(1), 2821 (2013)