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Showing papers by "Kumamoto University published in 2022"


Journal ArticleDOI
TL;DR: In this paper , a review of the use of carbon allotropes and relevant products for fuel cells and supercapacitors can be found, including carbon allotrope-based proton conductors for PEMFC electrolyte, carbon monoxide (CO) tolerant anode catalysts, and carbon all-otropes-based SC electrodes.
Abstract: Despite being generated from the same element and having some of the properties commonly shared, each type of carbon allotrope possessing divergent shape confers unique and distinguishable physicochemical properties, thereby making them attractive for a wide range of potential applications. Moreover, research progress has allowed for further tailoring the properties in a controlled way to design more fascinating and aesthetically pleasing architectures with outstanding materials properties. In fact, some chemically modified carbon allotropes and their products have shown significant promise to solve a number of major issues in polymer exchange membrane fuel cells (PEMFCs) and supercapacitors (SCs) such as efficient low Pt loaded oxygen reduction reaction (ORR) catalysts, carbon allotrope-based proton conductors for PEMFC electrolyte, carbon monoxide (CO) tolerant anode catalysts for PEMFC, and carbon allotropes-based SC electrodes. The tremendous progress made in carbon-based materials facilitates those technologies more realistically towards large-scale implementation in terms of increasing the stack power density and reducing cost. In this view, this review will provide a thorough insight for researchers into the use of carbon allotropes and relevant products for PEMFCs and SCs. Carbon allotropes including fullerene, CNT and graphene possess divergent shapes confering unique and distinguishable physicochemical properties. Moreover, research progress has allowed for further tailoring the properties in a controlled way to design more fascinating and aesthetically pleasing architectures with outstanding materials properties suitable for some key components in fuel cells and supercapacitors.

30 citations


Journal ArticleDOI
TL;DR: In this article, the authors investigated short-range order (SRO) solute clusters in the long-period stacking/order (LPSO) phases with an intrinsic-I (I1) type stacking faults (SFs), which have been uniquely formed in Mg-Co-Y alloys, based on atomic-resolution scanning transmission electron microscopy (STEM) combined with first-principles calculations.

26 citations


Journal ArticleDOI
TL;DR: In this article, the authors analyzed 54 open-dumping site soils collected from Cambodia, India, Indonesia, Laos, the Philippines, and Vietnam were analyzed for MP and found that daily-used plastic products are main sources of MP in these countries.

18 citations


Journal ArticleDOI
TL;DR: In this paper, the experimental and computational analyses of a 500m deep coaxial borehole heat exchanger system for geothermal power generation are studied in terms of fluid inlet and outlet temperatures, subsurface temperature distribution profiles over time, and flowrate.

17 citations


Journal ArticleDOI
TL;DR: In this article, the origin of non-uniform plasticity of the alloys produced by laser powder bed fusion (LPBF) has been systematically investigated for the first time, and the results show that the loss of uniform plasticity in the alloy originates from microstructural regions containing equiaxed fine-grains (FGs) (∼650 nm in size) at the bottom of the melt pools.

15 citations


Journal ArticleDOI
Yasuo Ariumi1
TL;DR: In this paper , the authors investigated the potential role of several host cellular RNA helicases in SARS-CoV-2 infection and showed that DDX21 and MOV10 helicases limit viral infection and replication.
Abstract: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has the largest RNA genome, approximately 30 kb, among RNA viruses. The DDX DEAD box RNA helicase is a multifunctional protein involved in all aspects of RNA metabolism. Therefore, host RNA helicases may regulate and maintain such a large viral RNA genome. In this study, I investigated the potential role of several host cellular RNA helicases in SARS-CoV-2 infection. Notably, DDX21 knockdown markedly accumulated intracellular viral RNA and viral production, as well as viral infectivity of SARS-CoV-2, indicating that DDX21 strongly restricts the SARS-CoV-2 infection. In addition, MOV10 RNA helicase also suppressed the SARS-CoV-2 infection. In contrast, DDX1, DDX5, and DDX6 RNA helicases were required for SARS-CoV-2 replication. Indeed, SARS-CoV-2 infection dispersed the P-body formation of DDX6 and MOV10 RNA helicases as well as XRN1 exonuclease, while the viral infection did not induce stress granule formation. Accordingly, the SARS-CoV-2 nucleocapsid (N) protein interacted with DDX1, DDX3, DDX5, DDX6, DDX21, and MOV10 and disrupted the P-body formation, suggesting that SARS-CoV-2 N hijacks DDX6 to carry out viral replication. Conversely, DDX21 and MOV10 restricted SARS-CoV-2 infection through an interaction of SARS-CoV-2 N with host cellular RNA helicases. Altogether, host cellular RNA helicases seem to regulate the SARS-CoV-2 infection. IMPORTANCE SARS-CoV-2 has a large RNA genome, of approximately 30 kb. To regulate and maintain such a large viral RNA genome, host RNA helicases may be involved in SARS-CoV-2 replication. In this study, I have demonstrated that DDX21 and MOV10 RNA helicases limit viral infection and replication. In contrast, DDX1, DDX5, and DDX6 are required for SARS-CoV-2 infection. Interestingly, SARS-CoV-2 infection disrupted P-body formation and attenuated or suppressed stress granule formation. Thus, SARS-CoV-2 seems to hijack host cellular RNA helicases to play a proviral role by facilitating viral infection and replication and by suppressing the host innate immune system.

13 citations


Journal ArticleDOI
TL;DR: The molecular docking studies predicted that the synthesized thiazole Schiff base derivatives are tolerable in putative receptor binding sites and follow the Lipinski's rule of five and Veber's rule with one exception.

12 citations


Journal ArticleDOI
TL;DR: The results of this study indicated that a deep learning method may not properly learn the explicit physical relationships between input and target variables, although they are still capable of maintaining strong goodnessof-fit results.

12 citations


Posted ContentDOI
08 Aug 2022
TL;DR: In this article , the effective reproduction number of BA.75 is greater than BA.2.2 and BA.5, the currently predominant BA.6.2 descendant, while BA.7.2 is a BA.4 descendant.
Abstract: Abstract SARS-CoV-2 Omicron BA.2.75 emerged in May 2022. BA.2.75 is a BA.2 descendant but is phylogenetically different from BA.5, the currently predominant BA.2 descendant. Here, we showed that the effective reproduction number of BA.2.75 is greater than that of BA.5. While the sensitivity of BA.2.75 to vaccination- and BA.1/2 breakthrough infection-induced humoral immunity was comparable to that of BA.2, the immunogenicity of BA.2.75 was different from that of BA.2 and BA.5. Three clinically-available antiviral drugs were effective against BA.2.75. BA.2.75 spike exhibited a profound higher affinity to human ACE2 than BA.2 and BA.5 spikes. The fusogenicity, growth efficiency in human alveolar epithelial cells, and intrinsic pathogenicity in hamsters of BA.2.75 were comparable to those of BA.5 but were greater than those of BA.2. Our multiscale investigations suggest that BA.2.75 acquired virological properties independently of BA.5, and the potential risk of BA.2.75 to global health is greater than that of BA.5.

10 citations


Journal ArticleDOI
Kyoko Miura1
TL;DR: The authors showed that NMRs exhibit extraordinary resistance against potent chemical carcinogenesis induction through a dampened inflammatory response, which may serve as a cancer resistance mechanism via attenuating the inflammatory response.
Abstract: Naked mole-rats (NMRs) have a very low spontaneous carcinogenesis rate, which has prompted studies on the responsible mechanisms to provide clues for human cancer prevention. However, it remains unknown whether and how NMR tissues respond to experimental carcinogenesis induction. Here, we show that NMRs exhibit extraordinary resistance against potent chemical carcinogenesis induction through a dampened inflammatory response. Although carcinogenic insults damaged skin cells of both NMRs and mice, NMR skin showed markedly lower immune cell infiltration. NMRs harbour loss-of-function mutations in RIPK3 and MLKL genes, which are essential for necroptosis, a type of necrotic cell death that activates strong inflammation. In mice, disruption of Ripk3 reduced immune cell infiltration and delayed carcinogenesis. Therefore, necroptosis deficiency may serve as a cancer resistance mechanism via attenuating the inflammatory response in NMRs. Our study sheds light on the importance of a dampened inflammatory response as a non-cell-autonomous cancer resistance mechanism in NMRs.

9 citations


Journal ArticleDOI
TL;DR: In this paper , the relationship between membrane pore size and fouling development was investigated using originally prepared chlorinated polyvinyl chloride (CPVC) flat-sheet membranes with different pore sizes in MBRs.
Abstract: Membrane bioreactors (MBRs) have been recognized as a promising wastewater treatment technique because of their superior solid–liquid separation performance; however, fouling development remains a concern. In this study, the relationship between membrane pore size and fouling development is investigated using originally prepared chlorinated polyvinyl chloride (CPVC) flat-sheet membranes with different pore sizes in MBRs; further, the mechanism of fouling development is demonstrated. Under the conditions in this study, the optimal membrane pore size for suppressing fouling development was determined to be in the range of 0.31–0.57 µm. It was also demonstrated that irreversible fouling is closely related to the capture of protein-like compounds inside the membrane; in contrast, it was considered that reversible fouling is caused by gel and cake layers formed on the membrane surface. Moreover, it was indicated that the membrane pore size directly and indirectly affected both reversible and irreversible fouling through the mutual relationship with other membrane characteristics such as the surface roughness. Finally, it is concluded that the optimal membrane pore size for suppressing fouling development is determined by the total filtration resistance caused by irreversible and reversible fouling phenomena.


Journal ArticleDOI
TL;DR: In this article , the authors evaluate the global mapping of VEGF-mediated dynamic transcriptional events, focusing on major histone-code profiles using chromatin immunoprecipitation sequencing (ChIP-seq).

Journal ArticleDOI
TL;DR: In this article, a non-heat-treated alloy that was prepared by consolidating the as-quenched ribbons exhibited a high tensile yield strength of ∼500 MPa, an elongation of ∼5%, and a plane-strain fracture toughness (KIc) of ∼9.5
Abstract: High fracture toughness Mg96.75Zn0.85Y2.05Al0.35 alloys featuring a multimodal microstructure were developed by rapidly solidified (RS) ribbon-consolidation processing. A non-heat-treated alloy that was prepared by consolidating the as-quenched ribbons exhibited a high tensile yield strength of ∼500 MPa, an elongation of ∼5%, and a plane-strain fracture toughness (KIc) of ∼9.5 MPa m1/2. Microstructure of the non-heat-treated alloy consists of two matrices: coarse-worked grains with a high kernel average misorientation (KAM) (group 1) and ultra-fine dynamically recrystallized (DRXed) grains with an intermediate KAM (group 2). The formation of ultra-fine DRXed grains with the precipitation of fine LPSO phase strengthens the alloy, but causes work-softening. The heat-treated alloy that was prepared by consolidating the RS ribbons heat-treated at 738 K exhibited a good balance of a high KIc (∼15 MPa m1/2), a reasonable yield strength (∼400 MPa), and a large elongation (∼12%) with a positive work-hardening rate. The optimized pre-consolidation heat-treatment produces multimodal microstructure having three matrices; a third group of the fine DRXed grains with a low KAM was formed in addition to groups 1 and 2. The formation of hierarchical multimodal structure in the grain size and KAM evokes strain-hardening, which has a positive effect on the fracture toughness.

Journal ArticleDOI
TL;DR: In this paper, a novel alcohol dehydrogenase (ADH), acetophenone reductase from Geotrichum candidum (GcAPRD), via physical adsorption was used as support to immobilize a novel ADH, which achieved 99% yield and > 99% ee (S).

Posted ContentDOI
03 Apr 2022
TL;DR: Wang et al. as discussed by the authors showed that the representative characteristics of the Omicron spike are determined by its receptor-binding domain, and further elucidated that the F375 residue forms an interprotomer pi-pi interaction with the H505 residue in another protomer in the spike trimer, which confers the attenuated spike cleavage efficiency and fusogenicity.
Abstract: Abstract Recent studies have revealed the unique virological characteristics of Omicron, the newest SARS-CoV-2 variant of concern, such as pronounced resistance to vaccine-induced neutralizing antibodies, less efficient cleavage of the spike protein, and poor fusogenicity. However, it remains unclear which mutation(s) in the spike protein determine the virological characteristics of Omicron. Here, we show that the representative characteristics of the Omicron spike are determined by its receptor-binding domain. Interestingly, the molecular phylogenetic analysis revealed that the acquisition of the spike S375F mutation was closely associated with the explosive spread of Omicron in the human population. We further elucidate that the F375 residue forms an interprotomer pi-pi interaction with the H505 residue in another protomer in the spike trimer, which confers the attenuated spike cleavage efficiency and fusogenicity of Omicron. Our data shed light on the evolutionary events underlying Omicron emergence at the molecular level. Highlights Omicron spike receptor binding domain determines virological characteristics Spike S375F mutation results in the poor spike cleavage and fusogenicity in Omicron Acquisition of the spike S375F mutation triggered the explosive spread of Omicron F375-H505-mediated π-π interaction in the spike determines the phenotype of Omicron

Journal ArticleDOI
TL;DR: In this article , the authors show that SOX2, which plays a key role in maintaining the pluripotency of stem cells, is critical for HERV-K LTR5Hs.
Abstract: Human endogenous retroviruses (HERVs) occupy approximately 8% of the human genome. HERVs, transcribed in early embryos, are epigenetically silenced in somatic cells, except under pathological conditions. HERV-K is thought to protect embryos from exogenous viral infection. However, uncontrolled HERV-K expression in somatic cells has been implicated in several diseases. Here, we show that SOX2, which plays a key role in maintaining the pluripotency of stem cells, is critical for HERV-K LTR5Hs. HERV-K undergoes retrotransposition within producer cells in the absence of Env expression. Furthermore, we identified new HERV-K integration sites in long-term culture of induced pluripotent stem cells that express SOX2. These results suggest that the strict dependence of HERV-K on SOX2 has allowed HERV-K to protect early embryos during evolution while limiting the potentially harmful effects of HERV-K retrotransposition on host genome integrity in these early embryos. IMPORTANCE Human endogenous retroviruses (HERVs) account for approximately 8% of the human genome; however, the physiological role of HERV-K remains unknown. This study found that HERV-K LTR5Hs and LTR5B were transactivated by SOX2, which is essential for maintaining and reestablishing pluripotency. HERV-K can undergo retrotransposition within producer cells without env expression, and new integration sites may affect cell proliferation. In induced pluripotent stem cells (iPSCs), genomic impairment due to HERV-K retrotransposition has been identified, but it is a rare event. Considering the retention of SOX2-responsive elements in the HERV-K long terminal repeat (LTR) for over 20 million years, we conclude that HERV-K may play important physiological roles in SOX2-expressing cells.

Journal ArticleDOI
TL;DR: In this paper, a new glioma stem-like cell (GSC), named U373-GSC, was established from the U373glioma cell line, which exhibited stemness properties, e.g., expression of stem cell markers, self-renewal activity, multi-lineage differentiating abilities, and drug resistance.

Journal ArticleDOI
TL;DR: In this paper, the authors used the submicron-sized liposome (ssLip) preparation to enhance drug accumulation in lung cancer cells and evaluated its physicochemical properties and potential as a drug carrier in pulmonary administration.

Journal ArticleDOI
TL;DR: In this paper , the N protein-coding region is widely analyzed in RT-qPCR to diagnose SARS-CoV-2 infection in Japan, and the authors found that the viruses showing abnormal amplification curves were Delta-type variants of SARS with a single nucleotide mutation in the probe-binding site.

Journal ArticleDOI
TL;DR: In this article, the authors conducted a nationwide survey conducted by the Japan Society of Gynecologic Oncology (JSGO), and interviewed 265 designated training facilities about the state of their clinical practice from the time period between March and December 2020.
Abstract: Objective As coronavirus disease 2019 (COVID-19) rages on, it is a challenging task to balance resources for treatment of COVID-19 and malignancy-based treatment. For the development of optimal strategies, assessing the conditions and constrains in treatment during the COVID-19 pandemic is pertinent. This study reported about a nationwide survey conducted by the Japan Society of Gynecologic Oncology. Methods We interviewed 265 designated training facilities about the state of their clinical practice from the time period between March and December 2020. We asked the facility doctors in charge to fill a web-based questionnaire. Results A total of 232 facilities (87.5%) responded. A decrease in the number of outpatient visits was reported, and the major reason attributed was reluctance of patients to visit hospitals rather than facility restrictions. The actual number of surgeries decreased by 3.9%, compared to 2019. There was a significant difference when the variable of "Prefectures operating under special safety precautions" or not was introduced. There was no increase in the rate of advanced stages in the three cancer types studied. However, 34.1% participants perceived COVID-19 affected management and prognosis. Conclusion Refraining from visiting hospitals based on the patient's judgment may be expected to be an issue in the future. No significant decrease in surgeries was observed, and it would seem that there were few forced changes in treatment plans, but "the State of Emergency" had an impact. There was no increase in the rate of advanced cancers, but this will need to be monitored.

Journal ArticleDOI
TL;DR: In this paper, the authors generalize Conway-Sloane's constructions of the Leech lattice from Niemeier lattices using Lorentzian lattice to holomorphic vertex operator algebras (VOA) of central charge 24.

Journal ArticleDOI
TL;DR: In this article , the enhanced super-resolution generative adversarial network (ESRGAN) was used to generate high-resolution data with ESRGAN and with the superresolution convolutional neural network (SRCNN).
Abstract: Abstract In this paper, we perform the super-resolution of sea surface temperature data with the enhanced super-resolution generative adversarial network (ESRGAN), which is a deep neural network-based single-image super-resolution (SISR) method that uses a generative adversarial network (GAN). We generate high-quality super-resolution data with ESRGAN and with the super-resolution convolutional neural network (SRCNN) and residual-in-residual dense block network (RRDBNet) methods, which are based on convolutional neural networks (CNNs). The images generated with these methods are compared with high-resolution optimum interpolation sea surface temperature (OISST) data using root mean square error (RMSE), learned perceptual image patch similarity (LPIPS), and perceptual index (PI) evaluation methods. RRDBNet has a better RMSE than SRCNN and ESRGAN. However, CNN-based SISR methods do not provide a faithful representation of the ocean currents of OISST. ESRGAN has a better LPIPS and PI than CNN-based methods and can represent the complex distribution of ocean currents.

Journal ArticleDOI
01 Jan 2022-iScience
TL;DR: Wang et al. as discussed by the authors show that cultured HSCs express mast cell-related genes including Cd244, and they suggest CD244 is a potent marker to exclude non-functional HSC after in vitro culture.

Journal ArticleDOI
TL;DR: In this article , a microwave aided efficient and green conversion of chitin to 5-hydroxymethylfurfural (5-HMF) while using polyoxometalate (POM) as a catalyst and DMSO/water as solvent was demonstrated.
Abstract: The key challenges for converting chitin to 5-hydroxymethylfurfural (5-HMF) include the low 5-HMF yield. Moreover, the disadvantages of traditional acid-base catalysts including complex post-treatment processes, the production of by-products, and severe equipment corrosion also largely limit the large-scale conversion of chitin to 5-HMF. In this view, herein we have demonstrated a microwave aided efficient and green conversion of chitin to 5-HMF while using polyoxometalate (POM) as a catalyst and DMSO/water as solvent. Chitin treated with H2SO4 followed by ball-milling (chitin-H2SO4-BM) was selected as the starting compound for the conversion process. Four different POMs including H3[PW12O40], H3[PMo12O40], H4[SiW12O40] and H4[SiMo12O40] were used as catalysts. Various reaction parameters including reaction temperature, amount of catalyst, mass ratios of water/DMSO and reaction time have been investigated to optimize the 5-HMF conversion. The H4[SiW12O40] catalyst exhibited the highest catalytic performance with 23.1% HMF yield at optimum operating conditions which is the highest among the literature for converting chitin to 5-HMF. Significantly, the disadvantages of the state of the art conversion routes described earlier can be overcome using POM-based catalysts, which makes the process more attractive to meet the ever-increasing energy demands, in addition to helping consume crustacean waste.

Journal ArticleDOI
TL;DR: In this article , a 93-year-old woman was diagnosed with Lysinibacillus fusiformis bacteremia complicated with coma blisters, and two-week administration of piperacillin/tazobactam and ampicillin resulted in an improvement of the patient's general condition, and the skin lesions gradually improved.

Journal ArticleDOI
TL;DR: This paper analyzed the interactions between organizational identity and the use of multiple languages within the lines of communication in the Thai, Taiwanese and US subsidiaries of a Japanese MNC, focusing especially on communications with customers and headquarters.

Book ChapterDOI
01 Jan 2022
TL;DR: In this paper, two types of motivational video materials were developed and investigated which type of video was effective and verified the effectiveness of narrative-based motivational materials, focusing on resilience and learning style as personal attributes.
Abstract: Before automated driving vehicles are put to practical use, people should know how those vehicles run and how a driver should operate them for safety. Some drivers are interested in learning about automated driving vehicles, others are less interested in it. There are individual differences in learning styles as well as a risk reduction method such as resilience. Thus, two types of motivational video materials were developed and investigated which type of video was effective. As a result, narrative-based motivational video was most effective. In short, this study especially focused on resilience and learning style as personal attributes and verified the effectiveness of narrative-based motivational materials.

DOI
01 Feb 2022
TL;DR: The authors showed that TICAM-1 is involved not only in TLR3 signaling but also in the cytokine receptor IL-17RA signaling, leading to enhanced expression of inflammatory cytokines and chemokines upon IL17A stimulation.
Abstract: TICAM-1 (also called TRIF) is the sole adaptor of TLR3 that recognizes double-stranded RNA. Here, we report that TICAM-1 is involved not only in TLR3 signaling but also in the cytokine receptor IL-17RA signaling. We found that TICAM-1 bound to IL-17R adaptor Act1 to inhibit the interaction between IL-17RA and Act1. Interestingly, TICAM-1 knockout promoted IL-17RA/Act1 interaction and increased IL-17A-mediated activation of NF-κB and MAP kinases, leading to enhanced expression of inflammatory cytokines and chemokines upon IL-17A stimulation. Moreover, Ticam-1 knockout augmented IL-17A-mediated CXCL1 and CXCL2 expression in vivo, resulting in accumulation of myeloid cells. Furthermore, Ticam-1 knockout enhanced delayed type hypersensitivity and exacerbated experimental autoimmune encephalomyelitis. Ticam-1 knockout promoted accumulation of myeloid and lymphoid cells in the spinal cord of EAE-induced mice. Collectively, these data indicate that TICAM-1 inhibits the interaction between IL-17RA and Act1 and functions as a negative regulator in IL-17A-mediated inflammatory responses.

Journal ArticleDOI
TL;DR: In this paper , a system for predicting COVID-19 patients in danger of death using portable chest X-ray images was proposed, where a total of 620 radiomic features were measured in the left and right lung regions.
Abstract: Introduction Computer-aided diagnostic systems have been developed for the detection and differential diagnosis of coronavirus disease 2019 (COVID-19) pneumonia using imaging studies to characterise a patient's current condition. In this radiomic study, we propose a system for predicting COVID-19 patients in danger of death using portable chest X-ray images. Methods In this retrospective study, we selected 100 patients, including ten that died and 90 that recovered from the COVID-19-AR database of the Cancer Imaging Archive. Since it can be difficult to analyse portable chest X-ray images of patients with COVID-19 because bone components overlap with the abnormal patterns of this disease, we employed a bone-suppression technique during pre-processing. A total of 620 radiomic features were measured in the left and right lung regions, and four radiomic features were selected using the least absolute shrinkage and selection operator technique. We distinguished death from recovery cases using a linear discriminant analysis (LDA) and a support vector machine (SVM). The leave-one-out method was used to train and test the classifiers, and the area under the receiver-operating characteristic curve (AUC) was used to evaluate discriminative performance. Results The AUCs for LDA and SVM were 0.756 and 0.959, respectively. The discriminative performance was improved when the bone-suppression technique was employed. When the SVM was used, the sensitivity for predicting disease severity was 90.9% (9/10), and the specificity was 95.6% (86/90). Conclusions We believe that the radiomic features of portable chest X-ray images can predict COVID-19 patients in danger of death.