Preparation of La2NiO4+δ powders as a cathode material for SOFC via a PVP-assisted hydrothermal route

Uniform submicron La₂NiO_4+δ (sm-LNO) powders have been synthesized by a facile polyvinylpyrrolidone (PVP)-assisted hydrothermal route. In the presence of PVP, sm-LNO of pure phase has been obtained by calcination at the relatively low temperature of 900 °C for 8 h. Compared micron-sized LNO (m-LNO) particles obtained at 1,000 °C by hydrothermal synthesis route without PVP assisted, the sm-LNO-PVP displays regularly shaped and well-distributed particles in the range of 0.3–0.5 μm. The scanning electron microscopy (SEM) results showed that the sm-LNO sample is submicronic and that the m-LNO sample shows agglomerates with a broad size distribution. The electrochemical performance of m-LNO and sm-LNO-PVP has been investigated by electrochemical impedance spectroscopy. The polarization resistance of the sm-LNO-PVP cathode reaches a value of 0.40 Ω cm² at 750 °C, which is lower than that of m-LNO (0.62 Ω cm²). This result indicates that a fine electrode microstructure with submicron particles can help to increase the active sites, accelerate oxygen diffusion, and reduce polarization resistance. An anode-supported single cell with sm-LNO cathode has been fabricated and tested over a temperature range from 650 to 800 °C. The maximum power density of the cell has achieved 834 mW cm⁻² at 750 °C. These results therefore show that this PVP-assisted hydrothermal method is an effective approach to construct submicron-structured cathode and enhance the performance of intermediate temperature solid oxide fuel cell.

Polybius’ ‘previous landslide’: Proof that Hannibal’s invasion route crossed the col de la traversette

Both Polybius and Livy described a landslide/landslip that blocked the Punic Army’s exfiltration from a high col on the water divide in the Western Alps. The landslide, more aptly termed rockfall, has been a source of contention amongst classicists for centuries despite the fact that only two cols—Clapier and Traversette—exhibit rockfall debris on the lee side of the Alps. While the Clapier rockfall is too small and too young to have provided blockage, the Traversette debris is nearly as Polybius described it when he retraced the invasion route some 60 years after the event. His ‘two-tier’ description of the deposit, a doublet of younger and older rock rubble, including measurements of width and volume are close to modern measurements and prove that he knew, in advance, the route Hannibal had followed. It would take a practiced eye to correctly identify the stratigraphic complexity inherent in the Traversette Rockfall. Here we present weathering ratios, soil stratigraphic, mineral, chemical and microbiological evidence in support of Polybius’ observations as a considerable background database for future geoarchaeological exploration.

Extracellular vesicle biogenesis in helminths: more than one route to the surface?

The quite recent discovery that parasites release extracellular vesicles (EVs) that can transfer a range of effector molecules to host cells has made us re-think our understanding of the host-parasite interface. In this opinion article we will consider how recent proteomics and transcriptomics studies, together with ultrastructural observations, suggest that more than one mechanism of EV biogenesis can occur in helminths. We propose that distinct EV sub-types have roles in immune-modulation and repair of drug-induced damage, and put forward the case for targeting EV biogenesis pathways to achieve parasite control. In doing so we raise a number of outstanding research questions that must be addressed before this can happen.

L'Asse Tripartito Italia-Germania- Giappone e la Cina

Germany, Italy and Japan were engaged in China from the turn of the 20th century to WWII. However, they formed an anti-Chinese alliance only at the final stage of their presence there, when Japan assumed an undisputed role of leader in the region. Despite its alliance with the Axis powers, Japan never implemented racial laws against the Jews in China. All of them took part in the Boxer Upraising suppression and received as a consequence extraterritorial rights and concessions. Moreover, Japan won the war against China in 1895 and transformed itself from a tributary country of China into an imperialistic power. It took possession of Taiwan and in the 1930s established a puppet government in Manchuria.Germany followed different route obtaining as indemnity for the murders of two missionaries the control of the Shandong province, which was later expanded thanks to the anti-Boxer coalition's victory. However, Germany lost all possessions when China entered WWI. The issue of Shandong was finally resolved at the Conference for Disarmament hold in Washington in 1921-2. Japan failed to gain ex-Germany territories. Finally, Italy arrived in the Far East at the turn of the century but was not very interested in the oriental colonialism to the same extent it was interested in Africa. Tianjin was its only concession in China, and it took almost a decade before a subvention to arrive from the Italian government for its development.In the 1920s and 1930s Germany and Italy engaged in successful diplomatic, commercial and military relationships with China. In fact, both were considered China's partners thanks to their experts at the service of the Chinese government. On the other hand, Japan position was opposite to them, because of its plans of aggression towards China which was to be transformed into “the natural extension” of the mainland. In 1935 Italy declared war on Ethiopia and abandoned the seat at the League of Nations. China interpreted the Italian aggression as the endorsement of Japan's politics towards China in Manchuria, and the relations between the two countries were broken off. After that Italy supported Wang Jingwei's puppet government during the Japanese occupation of China. Germany followed the same path in 1937, when it was evident that the Japanese were playing the leading role in the region, and decided to ally with Wang Jingwei too. Both Italy and Germany decided also to recognise the Manzhuguo and established diplomatic relations, definitively turning their backs on the old Chinese ally.The Rome-Berlin-Tokyo Axis sealed the alliance among the three countries, and it confirmed Japan as the leading power in the region. Nevertheless Japan did not apply the racial law against the Jews in China.