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This study investigated the sustainable room-temperature synthesis of In3Sn/γ-Ga2O3 core–shell particles via an acoustic route using molten eutectic Ga–In–Sn alloy (EGaInSn). Sonication was used for the emulsification and oxidation steps. During the emulsification step, the sonication of molten EGaInSn in ethanol (EtOH) at 45 kHz facilitated the formation of the smallest EGaInSn particles (average diameter, Dav = 782 nm). In terms of EGaInSn particle size, 45 kHz sonication was suitable for emulsification of molten EGaInSn and ethanol system than 24 kHz sonication.During the oxidation step, the preferential oxidation of Ga in the EGaInSn particles occurred via sonication in a solution of EtOH and hydrazine monohydrate (N2H4·H2O). This selective oxidation of Ga on the surface of the EGaInSn particles resulted in the formation of In3Sn/γ-Ga2O3 core–shell particles via sonication at 45 kHz and room temperature.The entire process eliminated the need for dispersants and high-temperature treatments. Additionally, the process did not generate waste fluid containing counter anions, such as chloride anions. This sustainable sonochemical method offers a carbon–neutral approach for synthesizing functional nanocomposites with improved safety, simplicity, and energy efficiency.

Sonochemical decomposition effects of nickelocene, which sublimates easily were investigated to synthesize dispersant-free nickel fine particles at low temperature. In a hydrazine monohydrate and 2-propanol mixed solvent, the reduction of nickelocene was promoted by ultrasound irradiation, and nickel fine particles were synthesized while precluding the sublimation of nickelocene. Unlike the common hydrazine reduction of nickel salts, which requires multiple-step reactions, nickelocene was reduced directly without forming intermediates. The effect of the water-bath temperature (20–60 °C) was investigated, where larger fine particles were synthesized using a higher water-bath temperature (60 °C). When irradiated at 20 °C, the reduction rate of nickelocene was low, leading to the formation of nickel fine particles and organic nanoparticles via the reduction and decomposition of nickelocene. The ultrasound frequency was also investigated, where fine nickel particles were synthesized using low-frequency ultrasound irradiation. The formation of high-temperature hotspots led to the diffusion and growth of nickel on the surface of the nickel fine particles; therefore, raspberry-like nickel fine particles were synthesized. In this study, the difficult-to-handle nature of nickelocene, owing to its sublimation properties, was easily overcome by ultrasound irradiation. Instantaneous and localized reactions at hotspots contributed to inhibiting particle growth. Furthermore, Ni fine particles were synthesized via a direct reduction pathway, which differs from previous reactions. This method represents a new, dispersant-free, low-temperature process for synthesizing Ni fine particles.

The waterglass or St o¨ ber method is commonly used to synthesize spherical colloidal silica; however, these methods have some disadvantages, such as complicated processes for the removal of sodium ions and expensive and energy-consuming raw materials such as tetraethoxysilane (TEOS). In this study, size-controlled spherical colloidal silica was synthesized from silicon metal at room temperature using an ultrasound process with hydrazine monohydrate as the solvent. Silicon metal dissolves easily in hydrazine monohydrate under ultrasound irradiation, and spherical colloidal silica can be synthesized by adding alcohol to this precursor solution. By changing the concentration or type of alcohol, size-controlled colloidal silica 20–200 nm in size could be easily obtained. In addition, finer and more monodisperse particles were produced by low-frequency ultrasound irradiation, which had a higher stirring effect at the particle formation stage. The present method is effective because size-controlled colloidal silica can be synthesized at room temperature using only silicon metal, hydrazine, and alcohol as raw materials, without complicated processes or expensive and energy-consuming raw materials such as TEOS or tetramethoxysilane (TMOS).

ABSTRACTA barium titanium oxide/silver (BaTiO3/Ag) nanocomposite powder was synthesized using a sonochemical process. By irradiating an ethanol solution of BaTiO3 and silver oxide (Ag2O), Ag2O thermally decomposed at 40°C and Ag-loaded BaTiO3 nanocomposites powder was obtained. Nanocomposites containing 30 vol% Ag sintered at 1000°C showed near densities and higher dielectric constants compared to those of BaTiO3 sintered at 1300°C. Moreover, percolation did not occur because the Ag nanoparticles were uniformly dispersed and loaded onto the surface of BaTiO3. This sonochemical method is expected to be a new process for obtaining uniformly dispersed and loaded nanocomposite powders without percolation, even in large amounts.

Abstract Radiotherapy (RT) plus immunotherapy is a promising modality; however, the therapeutic effects are insufficient, and the molecular mechanism requires clarification to further develop combination therapies. Here, we found that the RNA virus sensor pathway dominantly regulates the cellular immune response in NSCLC and ESCC cell lines. Notably, transposable elements (TEs), especially long terminal repeats (LTRs), functioned as key ligands for the RNA virus sensor RIG-I, and the mTOR–LTR–RIG-I axis induced the cellular immune response and dendritic cell and macrophage infiltration after irradiation. Moreover, RIG-I-dependent immune activation was observed in ESCC patient tissue. scRNA sequencing and spatial transcriptome analysis revealed that radiotherapy induced the expression of LTRs, and the RNA virus sensor pathway in immune and cancer cells; this pathway was also found to mediate tumour conversion to an immunological hot state. Here, we report the upstream and ligand of the RNA virus sensor pathway functions in irradiated cancer tissues.

Next-generation electronic materials must be produced and used sustainably. Nanocarbon materials have attracted much attention as next-generation materials because they have excellent properties and can be made from readily available and inexpensive raw materials. Among them, graphene is highly expected as a material that realizes high performance and energy saving in electric devices. It has excellent properties such as high electrical conductivity, high strength, and light weight. However, the current synthesis method for graphene requires the use of toxic chemicals such as strong oxidants and a large amount of energy consumption due to use of high vacuum and high temperature. Those requirements increases the environmental impact and cost. Therefore, a simple, environmentally friendly, inexpensive, and innovative process is required for the practical use of graphene. We have developed a novel process with a new mechanism using inexpensive and safe raw materials such as graphite, ice, and simple organic solvents and general equipment such as a microwave oven. The combination of the thermal expansion properties of graphite and the selective heating properties of microwaves created the new process. This paper shows that graphene synthesis can be achieved easily and cost-effectively using familiar equipment and materials by combining fundamental physical properties and phenomena.

Edamame is a green soybean that is rich in nutrients. Boiled edamame has been traditionally used for food in the East Asia region. It was known among farmers that conditions, such as temperature and climate on the day of harvest, affect the quality of edamame. Large-scale farmers harvest edamame on multiple days in the same year; however, the quality of edamame varies from day to day due to variations in climate conditions. In this study, we harvested edamame over several days between 2013 and 2018, obtained the climate conditions on the harvest date, and performed metabolome analysis using capillary electrophoresis mass spectrometry. To clarify the correlation between climate conditions before the harvest date and edamame components, comparative analyses of the obtained meteorological and metabolomic data were conducted. We found positive and negative correlations between the sunshine duration and average temperature, and the amounts of some edamame components. Furthermore, correlations were observed between the annual fluctuations in climate conditions and edamame components. Our findings suggest that the climate conditions before the date of harvesting are closely related to edamame quality.

Recently, environmental problems, such as global warming, have become more severe; thus, there is a requirement to implement sustainable development goals in materials processing. In this study, we investigated a low-cost and environmentally-friendly sonochemical process for the synthesis of metal nanoparticles with large specific surface areas and catalysis effects. Au2O3 hydrate and Ag2O were reduced to Au and Ag, respectively, at room temperature in a short time when irradiated with ultrasound in ethanol. Furthermore, when a mixed powder of Au2O3 hydrate and Ag2O was irradiated in ethanol, Au–Ag alloys were obtained in only 10 min. This fast and environmentally friendly alloying technique, known as sonochemical alloying, is promising for alloy syntheses.

In this study, we investigated the fabrication of supersaturated gallium (Ga)–aluminum (Al) liquid alloy and Al3+-doped γ-Ga2O3 nanoparticles (NPs) at near room temperature (60 °C) using sonochemical and sonophysical effects. Supersaturated Ga–Al liquid alloy microparticles (Dav = 1.72 µm) were formed and stabilized at 60 °C by the thermal nonequilibrium field provided by sonochemical hot spots. Compared with liquid Ga, supersaturated Ga–Al liquid alloy was rapidly oxidized to a uniform oxide without Al2O3 or Al deposition. Thus, ultrafine Al3+-doped γ-Ga2O3 NPs were obtained after only 1 h of ultrasonic irradiation at 60 °C. The oxidation of liquid Ga was remarkably accelerated by alloying with metallic Al and ultrasonic irradiation, and the time was shortened. The average diameter and surface area of the γ-Ga2O3-based NPs were 59 nm and 181 m2/g, respectively. Compared with γ-Ga2O3, the optical bandgap of the Al3+-doped γ-Ga2O3 NPs was broadened, and the thermal stability improved, indicating Al3+-doping into the γ-Ga2O3 lattice. However, the lattice constant of γ-Ga2O3 was almost unchanged with or without Al3+-doping. Al3+ was introduced into the defect sites of Ga3+, which were massively induced in the defective spinel structure during ultrasonic processing. Therefore, sonochemical processing, which provides nonequilibrium reaction fields, is suitable for the synthesis of supersaturated and metastable materials in metals and ceramics fields.

Colorectal cancer (CRC) is one of the most common malignant diseases. Generally, stoma construction is performed following surgery for the resection of the primary tumor in patients with CRC. The association of CRC with the gut microbiota has been widely reported, and the gut microbiota is known to play an important role in the carcinogenesis, progression, and treatment of CRC. In this study, we compared the microbiota of patients with CRC between with and without a stoma using fecal metagenomic sequencing data from SCRUM-Japan MONSTAR-SCREEN, a joint industry-academia cancer research project in Japan. We found that the composition of anaerobes was reduced in patients with a stoma. In particular, the abundance of Alistipes, Akkermansia, Intestinimonas, and methane-producing archaea decreased. We also compared gene function (e.g., KEGG Orthology and KEGG pathway) and found that gene function for methane and short-chain fatty acids (SCFAs) production was underrepresented in patients with a stoma. Furthermore, a stoma decreased Shannon diversity based on taxonomic composition but increased that of the KEGG pathway. These results suggest that the feces of patients with a stoma have a reduced abundance of favorable microbes for cancer immunotherapy. In conclusion, we showed that a stoma alters the taxonomic and functional profiles in feces and may be a confounding factor in fecal microbiota analysis.

Abstract Presynaptic active zone cytomatrix proteins are essential elements of neurotransmitter release machinery that govern neural transmission. Among active zone proteins, cytomatrix at the active zone-associated structural protein (CAST) is known to regulate active zone size in retinal photoreceptors and neurotransmitter release by recruiting Ca2+ channels at various synapses. However, the role of ELKS—a protein from the same family as CAST—and the synergistic roles of CAST/ELKS have not been thoroughly investigated, particularly with regard to mouse behavior. Here, we generated ELKS conditional KO in mouse forebrain synapses by crossing ELKS flox mice with a CaMKII promoter-induced Cre line. Results showed that CAST is dominant at these synapses and that ELKS can support CAST function, but is less effective in the ELKS single KO. Pups of CAST/ELKS double KO in the forebrain were born in Mendelian rations but resulted in eventual death right after the birth. Anatomically, the forebrain neuronal compositions of CAST KO and CAST/ELKS double KO mice were indistinguishable, and the sensory neural network from whiskers on the face was identified as barrelette-like patches in the spinal trigeminal nucleus. Therefore, depletion of CAST and ELKS disrupts neurotransmission from sensory to motor networks, which can lead to deficits in exploration and failure to suckle.

In this study, we investigated the influence of the addition of carbon materials on the heat resistance and flame retardancy of silica xerogels. A mixed dispersion prepared by adding 0.1 to 2.5 wt% each of the carbon materials, graphene oxide (GO), poly(3,4-ethylenedioxythiophene):poly(styrene sulfonic acid) (PEDOT:PSS), and carbon black (CB) to waterglass (SiO2 6%) was used as the raw material. By adding acid to this dispersion, a sol-gel reaction was carried out and the hydrogel obtained was hydrophobized with hydrochloric acid and a mixed solution of siloxane/isopropylalcohol . Finally, novel carbon-silica xerogel composites (SX-Carbon-X) were prepared via ambient pressure drying. Similarly, glass-fiber-reinforced silica xerogel composite sheets (GFR-SX-Carbon-X) were prepared by impregnating glass fibers with sol. The bulk densities of the samples obtained ranged from 0.204 to 0.217 g/cm3, their thermal conductivities ranged from 0.0187 to 0.0203 W/(m · K). As the amount of carbon material added was increased, the thermal decomposition temperature of the SX-Carbon-X shifted to higher temperatures. In the cone calorimeter test of GFR-SX-Carbon-X, moreover, adding at least 0.5% of the carbon material significantly reduced the combustion time and the peak heat release rate (PHRR), and the flame retardancy improved remarkably.

Silica xerogels were prepared by the sol-gel method under ultrasonic irradiation, using tetraethylorthosilicate (TEOS) as the starting material. Hexamethyldisiloxane (HMDSO) was used as the hydrophobizing agent. When preparing silica xerogel, it is necessary to perform aging and hydrophobization to suppress shrinkage during ambient pressure drying, however, such treatments are time-consuming. In this study, the semi-solid hydrogel was irradiated with ultrasonic for the first time in order to accelerate aging and hydrophobic treatment, and the effect of ultrasonic frequency on structure was investigated. Firstly, ultrasonic irradiation was performed at frequencies of 100 kHz and 500 kHz, followed by hydrophobic treatment at a frequency of 500 kHz, in order to promote aging. The results identify optimum conditions for ultrasonic irradiation to promote aging and hydrophobization reactions, and it was found to be possible to prepare silica xerogels in less than 1/5 of the conventional time. The silica xerogels had a low density and the shrinkage was suppressed. In this study, it was found that ultrasonic irradiation of semi-solid hydrogel was very effective for promoting the reaction.