Globeride (Japan)

Copper tubes used in heat exchangers were joined by brazing using copper phosphorus brazing filler metals. Leakage due to the progression of groove-like corrosion near the joints of copper tubes using copper phosphorus brazing filler metals became a problem. In addition to copper, copper phosphorus brazing filler metals also contained phosphorous and silver. In this study, we investigated the effects of silver on the corrosion resistance of copper phosphorus brazing filler metals. Observation and analysis of the metallographic structure of the copper phosphorus brazing filler metals revealed uneven distributions of phosphorus and silver components. Electrochemical measurements of anodic polarization curves showed that the current density of the copper phosphorus brazing filler metals with silver at high potentials was higher than that without silver. Furthermore, on the surface of the brazing material after the test, part of the structure of the silver-containing brazing material was observed to be corroded in the form of black dots. Therefore, the silver contained in the brazing material was considered to have effect on corrosion resistance of copper phosphorus brazing filler metals.

This study evaluates an AMD Zynq Ultrascale+ RF System-on-Chip (RFSoC) as an arbitrary waveform generator (AWG) for controlling atomic qubits coherently. We explore the advantages of using an RFSoC-based AWG for atomic qubit manipulation and experimentally demonstrate its utility in quantum computing. Our findings demonstrate that RFSoC is a scalable solution for developing large-scale quantum computers with atomic qubits, offering a promising approach for applications.

Residual carbon on the inner surface of copper tubes is known to be a cause of pitting corrosion. We showed previously that the rapid filling test was useful to evaluate the pitting corrosion resistance of copper tubes. Immersion tests using the rapid evaluation test solution showed that corrosion occurs on the entire surface of copper tubes with low residual carbon amounts, while those with high residual carbon amounts show pitting corrosion. Therefore, it is necessary to improve the corrosion resistance of copper tubes with high residual carbon amount, which are expected to undergo pitting corrosion. As pitting corrosion occurs when anodes are locally concentrated on part of the metal surface, it has been suggested that anodes be dispersed over the entire surface by the processing of the metal surface. Metal processing methods have various purposes, including changing the shape and properties of metals, and in this case, leading to desirable surface properties (such as expansion and drawing processes). Here, we focused on the expansion process and its effects on corrosion resistance of copper tubes. The results showed that hydraulic expansion has a significant effect on the inner copper surface by improving corrosion resistance as the anode area increases.

Abstract Acquired immune deficiency syndrome (AIDS) is the most advanced stage of human immunodeficiency virus (HIV) infection. As a retrovirus, HIV-1 is more virulent and prevalent compared to HIV-2. HIV infection leads to progressive loss of CD4+ T cells. The depletion of CD4+ T cells triggers a wide range of immunological abnormalities and hematological changes, increasing the risk of opportunistic infections and malignancies due to immunodeficiency. The current regimen of antiretroviral treatment (ART) is not curative, but durable viral load suppression is continued so that the person with HIV can maintain high CD4+ T cells for sustainable living. Although ART extends life expectancy, there comes a point where immunomodulation aiming to reduce HIV-associated immune activation and enhance the immune response to control HIV infection is still required. Biobran is a potent biological response modifier with immunomodulatory properties. The potential anti-HIV activity of Biobran was demonstrated via augmentation of lymphocyte proliferation in an HIV-infected individual. Biobran supplementation could potentially improve CD4+ T cells and CD4/CD8 ratio in HIV positive patients. Such findings support the potential use of Biobran as an adjunct therapy for people living with HIV.KeywordsAIDSHIVCD4+ T cellsImmunomodulationBiobran

Well-crystallized groundmass fractions are commonly used to obtain reliable K-Ar ages for volcanic rocks, as phenocrysts potentially contain excess 40Ar. In general, phenocrysts are removed by magnetic separator, heavy liquid separation, and hand picking. Heavy liquid separation utilizes sodium polytungstate (SPT) solution, which replaced toxic heavy liquids such as bromoform in the 1980s. Recently, a vacuum pump has been used to reduce the filtration time for heavy liquid separation using SPT solution, which has a high viscosity. This note describes the separation procedure for gentle suction filtration using a hand vacuum pump, which can be safely completed in 50-60 minutes per sample. The procedure was tested on andesite and basalt samples from Hakusan, Miyakejima, and Etna Volcanos. Separation of the groundmass fraction from the phenocryst fraction was successful for all andesite samples, whereas separation was incomplete in some of the basalt samples, probably because the gravity of groundmass grains was heavier than the maximum gravity of the SPT solution (3.11 g/cm3).

Hustai National Park in Mongolia became a refuge for takhi Equus ferus przewalskii, a wild horse native to central Asia, in 1992. Wild takhi became extinct in the wild in the 1960s, although there was a small captive population in European zoos that was used to repopulate Hustai National Park. This park is also inhabited by red deer Cervus elaphus, which may compete with takhi for food. We analyzed the fecal composition and habitat use of takhi and red deer. Takhi mainly foraged on grasses in the steppe, while red deer foraged on grasses and dicots in the forest. The percentage similarity (PS) of foods was 65% in summer and 58% in winter. There does not appear to be competition for food or habitat between these species because both diets and the habitat selection were different. We discuss some management implications and emphasize the importance of integrated management of the refuge.

Thousands of unexploded bombs that were air dropped during WWII are still underground in major cities in Japan.