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To achieve high energy efficiency and CO2 reduction during iron- and steelmaking, thermal management is vital. Use of phase change material (PCMs) to store excess energy in the form of latent heat has the potential to realize excellent thermal management. Microencapsulated PCMs (MEPCMs) consisting of an alloy PCM core and an oxide coating have improved corrosion resistance and are easy to mix with other materials. Conventionally, composite PCM pellets are fabricated by mixing glass frit (to aid sintering) with Al-25 mass% Si MEPCM. However, this process has not yet been optimized. In this study, the optimal stoichiometry of composite PCMs prepared using Al-25 mass% Si MEPCM and glass frit was investigated. The pellets were prepared by mixing with glass frit at 60, 80 and 90 mass% of MEPCM, followed by molding and heat treatment. As a result, pellets were successfully fabricated with condition including 60 and 80 mass% of MEPCM. The latent heat capacity of the composite PCM was 146 J g(-1), which was at least 1.59 times higher than that of existing sensible heat storage (SHS) materials. Moreover, the composite PCMs withstood 300 melting and solidification cycles. In summary, composite PCMs with excellent latent heat capacity and durability were successfully prepared.

The iron and steel industries currently face the depletion of high-grade ore and high CO2 emissions. Some initiatives that effectively utilize alternative carbon sources and abundant low-grade ores become the preferable solutions. This novel study aims to utilize municipal solid waste (MSW) as a reducing agent in ironmaking using low-grade (goethite) ores. As an initial fundamental approach, the comparison of decomposition behaviors between the model and actual MSW was investigated in thermogravimetric analysis. Both model and actual MSWs mainly decompose at 300-500 degrees C. As for reduction tests, pellets containing MSWs and ores with different pretreatments were prepared. The pellets were reduced in an Ar atmosphere at different temperatures. The effect of different ores: high-grade and low-grade ones, on the decomposition of MSW and the iron reduction, were investigated. As a result, interestingly, the low-grade, goethite ore-containing pellet exhibits a more significant reduction degree than the high-grade ones. The reduction is completed in 5 minutes at 700 degrees C and above, indicating a significant reduction by the decomposed carbon. The reduction degree extends at elevated temperature, which reaches more than 94% at 900 degrees C.

Gallium has been considered for application in the thermal management of electronic equipment because of its high heat transfer ability and heat storage density. To address the issues of metal corrosion and leakage, a microencapsulation method, through which a stable corrosion-resistant ceramic shell can be formed from the liquid metal, is proposed. In this study, an optimized fabrication method for a microencapsulated phase change material (MEPCM) consisting of liquid-state Ga droplets, possessing high durability and heat storage density, is presented. A fabrication route comprising particle formation, hydrothermal treatment, and calcination is proposed. In particular, the thickness and crystal size of the GaOOH shell are controlled by changing the pH during hydrothermal treatment to produce a highly durable shell. The morphology and microstructure, phase composition, heat storage capacity, and durability of the prepared Ga-MEPCM are investigated. In addition, treatment conditions and the shell formation mechanism are analyzed. The results show that pH 9 is the most suitable shell-forming condition, at which the thickest Ga2O3 shell with the smallest crystal size can be produced, which is beneficial for ensuring durability. The MEPCM achieved 200 cycles without leakage and 300 cycles without shape deformation with a high heat storage density of 369.4 J.cm(-3).

Hospital meals are prepared with the nutrients required by the patient's medical condition in consideration. However, no research on the purine content of hospital meals has been conducted, and it is not shown on the purine content. The recommended purine consumption for patients with gout and hyperuricemia is 400 mg/day based on the Japanese guidelines for the management of hyperuricemia and gout. In this study, the purine content in hospital meals was evaluated using the purine content of foods previously determined by our laboratory as a reference. The serum uric acid levels and uric acid excretion in admitted patients who consumed these diets were examined.

Antimicrobial resistance (AMR) of bacterial pathogens, including enterococci, is a global concern, and plasmids are crucial for spreading and maintaining AMR genes. Plasmids with linear topology were recently identified in clinical multidrug-resistant enterococci. The enterococcal linear-form plasmids, such as pELF1, confer resistance to clinically important antimicrobials, including vancomycin; however, little information exists about their epidemiological and physiological effects. In this study, we identified several lineages of enterococcal linear plasmids that are structurally conserved and occur globally. pELF1-like linear plasmids show plasticity in acquiring and maintaining AMR genes, often via transposition with the mobile genetic element IS1216E. This linear plasmid family has several characteristics enabling long-term persistence in the bacterial population, including high horizontal self-transmissibility, low-level transcription of plasmid-encoded genes, and a moderate effect on the Enterococcus faecium genome alleviating fitness cost and promoting vertical inheritance. Combined with its broad host range, the linear plasmid is an important factor in the spread and maintenance of AMR genes among enterococci.

Goethite (FeOOH)-based ore has become attractive to be utilized in ironmaking. As mildly dehydrated to remove its high combined water (CW), it changes to a nanoporous hematite ore. The nanopore contributes a significant increase in ore reduction reactivity due to the nanocontact between iron oxide and reducing agents such as C, CO, or H-2. However, the long dehydration time of goethite ore is still one problem. This study revealed the effect of vacuum condition on the mild-dehydration of goethite-based ore significantly reduces the ore dehydration time. The dehydration is finished within one hour at 300 degrees C under high-vacuum condition (P=1.7 Pa), producing nanoporous hematite ore that is similar to under atmospheric one for 24 h. However, no significant decrease in the dehydration temperature under the high-vacuum condition. In contrast, in-situ heating TEM observation reveals that nanopore generation can occur at low temperatures under ultra-high vacuum conditions (P = 5.6 x 10(-6) Pa). Slit pore generates at low temperatures that then eventually disappear by merging to bigger pores at the higher temperatures.

Phase change materials (PCM) and thermochemical materials (TCM) attract increasing attention as next-generation heat storage technologies. A novel CaO-supported microencapsulated phase change mater...

Carbonization of TiO2, which is a process typically used to synthesize TiC, consumes a huge amount of energy. Low-temperature synthesis of TiC from carbon-infiltrated TiO2 has been investigated in this study to develop an energy-saving process. Porous TiO2 was first obtained by hydrochloric acid leaching of ilmenite (FeTiO3) ore. Then, carbon-infiltrated TiO2 was prepared from the porous TiO2 using a tar impregnation method, and its reaction behavior was observed. The carbon-infiltrated TiO2 was completely converted into TiC which contained 3.0 mol pct oxygen at 1300 °C for 2 hours. In contrast, a mixture of reagents TiO2 and carbon did not react when it was subjected to the same treatment. This major difference is due to the effect of close contact between TiO2 and carbon through the nanopores generated in TiO2 obtained by acid leaching of ilmenite ore. It was concluded that this method has significantly lower temperature and much shorter reaction time than those of conventional methods.

Background Limited research has been conducted on the surgical management of the aortic valve in congenitally corrected transposition of great arteries (ccTGA) and to our knowledge there have been no reports on the treatment of bicuspid aortic regurgitation (AR) in ccTGA. We report on a ccTGA patient with bicuspid AR and systemic right ventricule (SRV) dysfunction who underwent transcatheter aortic valve replacement (TAVR). Case summary A 17-year-old male with a history of ccTGA and cerebral palsy diagnosed at birth presented with heart failure. During childhood, he did not experience any heart failure symptoms, however, secondary to progressive bicuspid AR he experienced worsening SRV dysfunction beginning at 15-year-old. Echocardiography showed reduced SRV ejection fraction and severe bicuspid AR. The heart team, including a cardiac surgeon and paediatric cardiologist, discussed the treatment strategies and decided to proceed with TAVR as surgical aortic valve replacement was deemed high risk. TAVR was performed with the 34 mm Evolut R (Medtronic, Minneapolis, MN, USA). Post-operative echocardiography showed severe paravalvular leak (PVL). Therefore, valve-in-valve TAVR using a 29 mm Edwards SAPIEN 3 (Edwards Lifesciences, Irvine, CA, USA) was performed on post-operative Day 2 for PVL reduction. Following second procedure, PVL was significantly improved. The patient was discharged in stable condition. Discussion This is the first case wherein TAVR was performed for bicuspid AR in a patient with ccTGA. With appropriate preparation and planning and a collaborative multi-disciplinary team approach, TAVR can be a treatment option for severe AR in patients with ccTGA at high risk for surgery.

The effects of mechanical stress on cultured muscle cells were examined with particular interest in myofibril assembly by using a cell-stretching system. We observed that formation and maintenance of cross-striated myofibrils in chick muscle cell cultures was suppressed in the media containing higher concentration of KCl, tetrodotoxin, or ML-9 (an inhibitor of myosin light chain kinase), but periodic stretching of myotubes for several days enabled formation of striated myofibrils just as in standard muscle cultures. However, ryanodine (a blocker of the Ca

Background VanD is a rare type of vancomycin resistance worldwide. However, the host diversity of the vanD gene cluster and the structural similarity of their genomic islands are not well understood. Methods Three VanD-type Enterococcus faecium strains (AA620, AA622 and AA624) isolated from a Japanese patient who underwent vancomycin treatment in 2017 were analysed. This study utilized WGS analysis to characterize the three VanD-type E. faecium strains and describes the diversity of hosts possessing VanD-carrying genomic islands. Results The three isolates exhibited variable MICs of vancomycin. In the relatively vancomycin-resistant AA620, mutations were identified in vanSD and ddl. The strains AA622 and AA624 had intact ddl and harboured two vanD gene clusters. qRT-PCR results revealed the ddl mutation to be a factor affecting the high vancomycin resistance range of AA620. WGS data showed the 155 kb and 185 kb genomic islands harbouring the vanD gene cluster inserted in the coding region of the lysS gene, located in the chromosome in AA620 and AA622/624, respectively. Comparing the VanD-carrying genomic islands to available sequences of other enterococci and enteric anaerobes revealed how the genomic islands of these organisms isolated worldwide shared similar core genes and backbones. These anaerobes belonged to various genera within the order Eubacteriales. The phylogenetic cluster of the genomic island core genome alignment did not correlate with the host-species lineage, indicating horizontal gene transfer in the gut microbiota. Conclusions By horizontal gene transfer, various bacteria forming the gut microbiota maintain VanD-carrying genomic islands.

Five novel strains of Serratia fonticola that produce FONA, a minor extended spectrum beta-lactamase (ESBL), were isolated during the routine surveillance of ESBLproducing Enterobacteriaceae in imported chicken meat in Japan in 2017 and 2018. These strains exhibited a clear ESBL phenotype in susceptibility tests carried out in the presence of clavulanic acid; however, they were all negative in the multiplex polymerase chain reaction assay used to detect the TEM, SHV and CTX-M β-lactamase genes. After identification of the bacterial species as S. fonticola, full blaFONA genes were amplified and the DNA sequences were determined. The blaFONA genes from all five strains were different from those previously reported (blaFONA-1 to blaFONA-6); they clustered closely with one another but were distinct from previously reported blaFONA genes in a phylogenic analysis based on amino acid sequences.

Background Ventricular‐arterial coupling predicts outcomes in patients with heart failure. The arterial elastance to end‐systolic elastance ratio (Ea/Ees) is a noninvasively assessed index that reflects ventricular‐arterial coupling. We aimed to determine the prognostic value of ventricular‐arterial coupling assessed through Ea/Ees after transcatheter aortic valve replacement to predict clinical events. Methods and Results We retrieved data on 1378 patients (70% women) who underwent transcatheter aortic valve replacement between October 2013 and May 2017 from the OCEAN‐TAVI (Optimized transCathEter vAlvular iNtervention) Japanese multicenter registry. We determined the association between Ea/Ees and the composite end point of hospitalization for heart failure and cardiovascular death by classifying the patients into quartiles based on Ea/Ees values (group 1: 0.666) during the midterm follow‐up after transcatheter aortic valve replacement. During a median follow‐up period of 736 days (interquartile range, 414–956), there were 247 (17.9%) all‐cause deaths, 89 (6.5%) cardiovascular deaths, 130 (9.4%) hospitalizations for heart failure, and 199 (14.4%) composite events of hospitalization for heart failure and cardiovascular death. The incidence of the composite end point was significantly higher in group 2 (hazard ratio [HR], 1.76; 95% CI, 1.08–2.87 [ P =0.024]), group 3 (HR, 2.43; 95% CI, 1.53–3.86 [ P P P =0.015]). Conclusions These findings suggest that a higher Ea/Ees at discharge after transcatheter aortic valve replacement is associated with adverse clinical outcomes during midterm follow‐up. Registration URL: https://www.upload.umin.ac.jp/ . Unique identifier: UMIN000020423.

Ascending aortic dilatation occurs frequently in patients with aortic stenosis (AS) [(1)][1]. In our study, we sought to investigate the prevalence, characteristics, and clinical impact of ascending aortic dilatation in patients undergoing transcatheter aortic valve replacement (TAVR) for tricuspid

Combustion synthesis (CS) of silicon nitride (Si3N4), assisted by molten salt additives under high N2 pressure, is reported. The effect of salt additives (NaCl, MgCl2, and MgCl2∙6H2O) on the reaction temperature and the final α-Si3N4 content is studied. The maximum reaction temperature (Tmax) decreased with an increase in the amount of the salt additives. NaCl is found to be the most suitable as it results in 57.8% α-Si3N4 at 30 mass% concentration. MgCl2 is strongly hygroscopic, and MgCl2∙6H2O decomposes at very low temperature. Therefore, they absorb heat at low temperatures, which makes it difficult to reach the ignition temperature, thereby hindering the reaction propagation. Si3N4 is necessary as a diluent for creating pores in the raw materials to allow effective penetration and contact of N2 gas with the Si particles.

The purpose of this study was to prepare an Al/Al2O3 core–shell microencapsulated phase-change material (MEPCM) for a high-temperature thermal energy storage (TES) system. Al (melting temperature: 660 °C) was selected as a raw material for use as a phase change material (PCM). The MEPCM was prepared in two steps: (1) the formation of an AlOOH precursor shell on the PCM microspheres via boehmite treatment in boiled distilled water and (2) heat oxidation treatment in an O2 atmosphere to form a stable Al2O3 shell. The effects of the heat oxidation temperature on the shell morphology, shell structure, heat capacity, and cyclic durability of the prepared MEPCMs were examined. The resultant MEPCM was a core–shell-type structure composed of a stable α-Al2O3 shell and an Al core. The melting temperature of the MEPCMs was close to that of pure Al, and small supercooling of approximately 10 K was observed. Although the increase of the heat oxidation temperature reduced the heat-storage capacity of the MEPCMs (273–301 J g−1) as larger amounts of Al were consumed to form α-Al2O3, the repetition durability of the developed specimens was improved by increasing the heat-treatment temperature. In conclusion, the Al-based MEPCM is a potential candidate for high-temperature TES applications owing to its high melting temperature, high thermal storage capacity, and small degree of supercooling.

This paper describes a high thermal conductive phase change composite (PCC) of erythritol and Al filler with percolating network. The PCCs with various Al amounts were prepared by both melt-dispersion method and hot-press (HP) method. The effective thermal conductivity of PCCs was measured, and the distribution status of the erythritol and Al filler was observed. The percolated filler network in the PCCs can be easily formed by HP method, which is important for enhancing the thermal conductivity of PCCs. The PCM particles with nonuniform particle size and high packing ratio is essential for the formation of filler percolating network. A high thermal conductivity of 30 W m−1 K−1 can be obtained at a filler fraction of 42.2 vol%.

The practical use of organic phase change materials (PCMs) for solar thermal energy storage is limited by the leakage problem and the low thermal conductivity. As a good supporting and thermal conductive framework for organic PCM with shape-stability, three-dimensional carbon sponges are produced by the direct carbonization of low-cost and sustainable biomass cotton. The carbon sponges are consisted of aerogels of the cotton-derived hollow carbon fibers, which have both interconnecting network and high porosity. The vacuum impregnated paraffin@carbon sponge composites not only present leakage-proof shape stability and enhanced thermal conductivity, but also show high thermal storage energy density (>200 J g-1, slightly lower than the pure paraffin) and good cyclability. The results indicate that the shape-stable PCMs as supported by cotton-derived carbon sponges are potentially to be widely used for thermal energy conversion and storage, especially for solar energy utilization.

High temperature phase change materials (PCMs) are drawing increasing attentions globally due to their high latent heat storage ability for solar thermal energy. Encapsulation of PCMs is an effective method for preventing the leakage of liquid PCM during heat storage, which makes PCMs easier to handle. In this paper, the synthesis of microencapsulated PCM (MEPCM) with Al-25 wt% Si core (spheres, average diameter 36 µm) and Al2O3@Cu multilayered shell is reported, which works at temperature up to 500 °C. The homogeneous and effective composite shell is synthesized in multi-steps: First, a boehmite (AlOOH) shell is formed by boiling treatment in water, which is then transferred to Al2O3 shell by heating at 500 °C. Second, the Al2O3 covered particles are etched with HCl solution. Third, electroless plating of Cu layer is carried out to form the multilayered MEPCM. The surface morphology, cross-sectional structure, and thermal durability and stability of the MEPCM are investigated. The core/shell Al-25 wt%Si@Al2O3@Cu particles can maintain their integrity even after 100 melting–solidification cycles with a low breakage ratio of about 1.7%. The results indicate that as-prepared MEPCM can be used for high temperature thermal energy storage such as solar thermal power generation. The success of Cu plating on spherical particles can also be applied to fabricate other Cu coated PCMs due to expected high thermal conductivity of Cu, especially for the low temperature ones such as organic PCMs.

In the gasification process, tar material may cause operational problems, such as carbon deposition over a catalyst, pipe plugging, condensation, and tar aerosol formation. Unusual approaches shoul...

The wide application of organic phase change materials for thermal energy storage and management is limited by their low thermal conductivity and poor shape stability. In this work, anisotropic thermally conductive and shape-stabilized phase change composites (PCCs) were successfully prepared with vertically aligned carbon fibers as supporting scaffolds. The aligned and hollow carbon fiber scaffolds with different densities were facilely fabricated by the direct carbonization of rolled cotton sheets with aligned and hollow cellulose fibers. PCCs were obtained by vacuum impregnation of paraffin wax. Because of the interconnected hollow carbon fiber frameworks with vertically aligned fibers and high porosity, PCCs present enhanced anisotropic thermal conductivity and good shape stability against leakage. The thermal conductivity in the axial direction along the fibers is higher than that in the lateral direction, since the aligned fiber scaffolds act as the thermal conduction pathway. The thermal conductivity of a PCC with a carbon ratio of 8.8 wt% is 0.77 W K-1 m(-1) (>3 times that of pure paraffin) in the axial direction, while the value in the lateral direction is 0.58 W K-1 m(-1). This work provides a novel strategy for designing anisotropic thermally conductive and shape-stabilized PCCs with potential applications in advanced thermal management and storage.

CO2 methanation is a promising technology to enable the use of CO2 as a resource. Thermal control of CO2 methanation, which is a highly active exothermic reaction, is important to avoid thermal runaway and subsequent degradation of the catalyst. Using the heat storage capacity of a phase change material (PCM) for thermal control of the reaction is a novel passive approach. In this study a novel structure was developed, wherein catalysts were directly loaded onto a micro-encapsulated PCM (MEPCM). The MEPCM was prepared in three steps consisting of a boehmite treatment, precipitation treatment, and heat oxidation treatment, and an impregnation process was adopted to prepare a Ni catalyst. The catalyst-loaded MEPCM did not show any breakage or deformation of the capsule or a decrease in the heat storage capacity after the impregnation treatment. MEPCM demonstrated a higher potential as an alternative catalyst support in CO2 methanation than the commercially available α-Al2O3 particle. In addition, the heat storage capacity of the catalyst-loaded MEPCM suppressed the temperature rise of the catalyst bed at a high heat absorption rate (2.4 MW m-3). In conclusion, ​the catalyst-loaded MEPCM is a high-speed, high-precision thermal control device because of its high-density energy storage and resolution of a spatial gap between the catalyst and cooling devices. This novel concept has the potential to overcome the technical challenges faced by efficiency enhancement of industrial chemical reactions.

Five novel strains of Serratia fonticola that produce FONA, a minor extended-spectrum beta-lactamase (ESBL), were isolated during routine surveillance of ESBL-producing Enterobacteriaceae in imported chicken meat in Japan in 2017 and 2018. These strains exhibited a clear ESBL phenotype in susceptibility tests carried out in the presence of clavulanic acid; however, all strains tested negative in a multiplex polymerase chain reaction assay used to detect TEM, SHV, and CTX-M β-lactamase genes. After identification of the bacterial species as S. fonticola, full length bla

By tuning the physical and chemical pressures of layered perovskite materials we can realize the quantum states of both superconductors and insulators. By reducing the thickness of a layered crystal to a nanometer level, a nanofilm crystal can provide novel quantum states that have not previously been found in bulk crystals. Here we report the realization of high-temperature superconductivity in Ca2RuO4 nanofilm single crystals. Ca2RuO4 thin film with the highest transition temperature Tc (midpoint) of 64 K exhibits zero resistance in electric transport measurements. The superconducting critical current exhibited a logarithmic dependence on temperature and was enhanced by an external magnetic field. Magnetic measurements revealed a ferromagnetic transition at 180 K and diamagnetic magnetization due to superconductivity. Our results suggest the co-appearance of superconductivity and ferromagnetism in Ca2RuO4 nanofilm crystals. We also found that the induced bias current and the tuned film thickness caused a superconductor-insulator transition. The fabrication of micro-nanocrystals made of layered material enables us to discuss rich superconducting phenomena in ruthenates.

Little information is available on computed tomography (CT)-based predictors of stroke related to transcatheter aortic valve replacement (TAVR). The objective of this study was to determine whether anatomical features of the aortic valve and aorta visualized by CT are predictive parameters of stroke.The study included 1270 patients who underwent preprocedural contrast-enhanced CT assessment and TAVR for severe aortic valve stenosis. Twenty-six patients (2.5%) who developed acute strokes that occurred within 48 hours after TAVR and 104 matched patients without strokes were identified, using 1:4 propensity-score matching. The degree of hypoattenuation in the aortic valve leaflets, calcium volume of the aortic valve, and plaque thickness in the aortic wall (the ascending aorta, aortic arch, and descending thoracic aorta) were assessed.There were no differences between the two groups in the degree of hypoattenuation in the aortic valve leaflets and calcium volume of the aortic valve. The plaque thickness of the aortic arch and descending aorta were greater in the stroke group than in the non-stroke group: aortic arch, 2.4 mm (IQR, 1.3-2.8 mm) vs 1.8 mm (IQR, 1.4-2.2 mm), respectively (P.01); and descending aorta, 2.9 mm (IQR, 2.1-4.2 mm) vs 2.8 mm (IQR, 2.1-3.6 mm); respectively (P=.049).Aortic wall plaque thickness measured by contrast-enhanced CT might be a predictive parameter of strokes that occur within 48 hours after TAVR.