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Key Clinical Message Insertion of a nasogastric tube is one of the most common methods of administering nutrition, but can cause vocal cord paralysis.

The 3D printer using Fused Deposition Modeling (FDM) is attracting attention as a manufacturing technology that is able to reduce the production time and the manufacturing costs. However, the information on the mechanical properties and the process parameters that affect to the safety and the reliability of the shaped object is less than that for metallic materials. Therefore, it is desirable to detect and evaluate the phenomena such as “Craze occurrence/growth” and “In- or Inter-layer failure/fracture”. In this study, tensile tests were conducted to the two type specimens with different stacking directions. Then, it was attempted to extract the characteristics of those phenomena from the results of chaos analysis of AE signals detected during the test. The following findings were made clear. (1) The frequency ranges that characterize the respective phenomena were determined. (2) The chaos parameters of AE waveforms in which the signals were separated into the frequency range of each phenomenon using the Empirical Mode Decomposition (EMD), enabled the characteristics of that phenomenon. (3) Differences in stacking direction affect the chaotic characteristics of AE waveforms emitted by each phenomenon.

This study aims to understand the mechanical properties of cellulose nanofibers (CNFs), a nano-sized material element of woods or plants. We develop all-atom (AA) molecular dynamics models of cellulose microfibrils (CMFs), which are the smallest constituent of CNFs. The models were designed for the process of structural failure or the degradation of a hierarchical material of multiple CMF fibers, due to shear deformation. It was assumed that two CMFs were arranged in parallel and in close contact, either in a vacuum or in water. The CMF models in water were built by surrounding AA-modeled water molecules with a few nanometers. Shear deformation was applied in the axial direction of the CMF or in the direction parallel to molecular sheets. Shear moduli were measured, and they agree with previous experimental and computational values. The presence of water molecules reduced the elastic modulus, because of the behavior of water molecules at the interface between CMFs as a function of temperature. In the inelastic region, the CMF often broke down inside CMFs in a vacuum condition. However, in water environments, two CMFs tend to slip away from each other at the interface. Water molecules act like a lubricant between multiple CMFs and promote smooth sliding.

Objective(s): Computed tomography (CT) images are used for precise anatomical location of lesions and for accurate attenuation correction in single-photon emission computed tomography (SPECT) image reconstruction in SPECT/CT examination. The aim of this study was to verify the effects of varying CT collimation width and slice thickness on CT images and on CT attenuation corrected SPECT images.Methods: We acquired SPECT/CT images of a micro-coin phantom and the National Electrical Manufacturers Association body phantom filled with 99mTc-pertechnetate while varying the abovementioned CT parameters. The full width at half maximum of the slice sensitivity profile, the standard deviation of CT image background noise, and the radiation dose from CT scans were evaluated. Subsequently, the percentage contrast, background variability, and absolute recovery coefficient of the SPECT image were measured. Furthermore, we retrospectively reviewed the clinical bone SPECT images of 23 patients, and statistical testing of differences was performed.Results: As the collimation width and reconstruction slice thickness of the CT image increased, z-axis resolution deteriorated, and background noise decreased. In addition, CT radiation dose decreased with increasing collimation width. Meanwhile, SPECT image quality and quantitative accuracy were unchanged with varying CT collimation width and slice thickness. There were no notable variations in clinical SPECT images and no statistically significant differences.Conclusion: When high-resolution CT slices on the z-axis are not required for clinical diagnosis, increasing collimation width or slice thickness can reduce the radiation dose and image noise with no influence on the quality of SPECT images.

Abstract Dialysis‐related adverse reactions can be serious and difficult to predict. In our case, nafamostat mesylate (NM) was thought to be the cause of cardiopulmonary arrest (CPA) due to NM‐induced anaphylaxis but was not reflected in the allergy tests. Rare but life‐threatening drawbacks occur immediately after hemodialysis initiation.

Lead bronze had been widely used as the bearing materials. However, the utilization of that material is limited, because the lead and the lead compound are noxious to the human body. Therefore, though the lead free bronze (LFB) alloys using the rare metals are developed, the problem on resources has been pointed out. On the other hand, the powder of LFB including the sulfide (Cu5FeS4) of Cu-Fe-S series was developed, and it was reported that the materials sintered the powder show the higher sliding characteristics than those of lead bronze. Therefore, the bimetal materials sintered after spraying that powder on the substrates have achieved high functionality. However, it is desired to establish the method for quantitatively evaluating the progress of the breakage conditions and for acquiring the design information on the realization of the requested mechanical properties. By comparing the breakage types occurred in the tensile test with the characteristics of the AE events emitted by those types, the parameters for evaluating those types were proposed and those effectiveness were reported in the previous study. On the other hand, the establishment of the life judgment method is desired as the main causes of many breakage accidents are fatigue phenomenon. However, the accident analyses are difficult because the traces of the breakage are not clear as for the fatigue breakage of the sintered materials. In this study, the Ib-value derived from the amplitude distribution of the AE events detected in the fatigue test was applied for the life judgement, and that effectiveness was examined.

Abstract Assessing the hERG liability in the early stages of drug discovery programs is important. The recent increase of hERG-related information in public databases enabled various successful applications of machine learning techniques to predict hERG inhibition. However, most of these researches constructed the datasets from only one database, limiting the predictability and scope of the models. In this study, a hERG classification model was constructed using the largest dataset for hERG inhibition built by integrating multiple databases. The integrated dataset consisted of more than 291,000 structurally diverse compounds derived from ChEMBL, GOSTAR, PubChem, and hERGCentral. The prediction model was built by support vector machine (SVM) with descriptor selection based on Non-dominated Sorting Genetic Algorithm-II (NSGA-II) to optimize the descriptor set for maximum prediction performance with the minimal number of descriptors. The SVM classification model using 72 selected descriptors and ECFP_4 structural fingerprints recorded kappa statistics of 0.733 and accuracy of 0.984 for the test set, substantially outperforming the prediction performance of the current commercial applications for hERG prediction. Finally, the applicability domain of the prediction model was assessed based on the molecular similarity between the training set and test set compounds.

Replacement of exhaustible and harmful resources used as solid lubricants is required for sliding elements such as plain bearings. In particular, the substitution of lead containing in the lead bronze is considered an urgent task. Therefore, in this study, attention was focused on metal sulfides (Cu2S, Cu5FeS4, SnS, TiS2, etc) as a substitute material for lead. After synthesis of sulfide and preparation of sintered body, friction and abrasion test was carried out and applicability as solid lubricant was investigated. The tribological properties of the dry conditions were evaluated by a journal type high speed tester. As a result, the friction coefficient of the bronze specimen without sulfide was about 0.3, whereas the bronze specimen containing sulfide showed a friction coefficient of about 0.1, indicating that the sulfide reduced the frictional resistance. Among them, the specimens containing Cu2S and Cu5FeS4 exhibited a lower friction coefficient. It is considered that this is influenced not only by the effect of hardness but also by film formation by sulfide.

Due to great interest in the development of electric vehicles and other applications, improving the performances of lithium-ion batteries (LIBs) is crucial. Specifically, components of electrolytes for LIBs should be adequately chosen from hundreds of thousands of candidate compounds. In this study, we aimed to evaluate some physical properties expected for combinations of molecules for electrolytes by microscopic simulations. That is, the viscosity, ionic conductivity, degree of dissociation, diffusion coefficient, and conformation of each molecule were analyzed via molecular dynamics (MD) simulations. We aimed to understand how molecular-sized structures and properties collaboratively affect the behavior of electrolytes. The practical models of molecules we used were ethylene carbonate (EC), fluoroethylene carbonate (FEC), propylene carbonate (PC), butylene carbonate (BC), γ-butyrolactone (GBL), γ-valerolactone (GVL), dimethyl carbonate (DMC), ethyl-methyl carbonate (EMC), diethyl carbonate (DEC), and lithium hexafluorophosphate (LiPF6). Many molecular systems of electrolytes were simulated, in which one molar LiPF6 was mixed into a single or combined solvent. It was found that small solvent molecules diffused with relative ease, and they contributed to the higher ionic conductivity of electrolytes. It was clarified that the diffusion coefficient of lithium (Li) ions is greatly affected by the surrounding solvent molecules. We can conclude that high-permittivity solvents can be selectively coordinated around Li ions, and Li salts are sufficiently dissociated, even when there is only a small content of high-permittivity solvent. Thus, we can confirm solely by MD simulation that one of the better candidates for solvent molecules, formamide (F), will exhibit higher performance than the current solvents.

The part of rail joint becomes the cause of the disadvantage points such as ride discomfort, undesired sound and track maintenance, etc. For restraining those points, the long rail made by welding the standard length rails has been developed. However, the problems of the buckling caused by the axial stress (i.e. the thermal stress which is brought out by the weather conditions or the friction heat between wheel and rail) of the rail have been pointed out. Therefore, some evaluation techniques for buckling management have been proposed. In this study, the relationship between the increase in compressive stress and the behaviors of the characteristics of the wavelet transform (i.e. a kind of time-frequency analysis) results of ultrasonic echoes was researched. The stress was increased in 10 [MPa] interval, and the echo at each stress was detected. From the results of experiment and analysis, it became clear that there is the relatively correlation between three characteristics and the stress. They are RMWC, RWE and RKTW respectively. The value of each RMWC, RWE and RKTW shows the ratio to the initial value (i.e. shows at 0[MPa] in this case) of MWC (i.e. the maximum wavelet coefficient), WE (i.e. wavelet energy) and KTW (i.e. the kurtosis of the time fluctuation waveform of the wavelet coefficient of the frequency that indicates MWC). Therefore, it was able to show the possibility of comparatively accurately predicting the increment of the stress by comparing the transitions of those.

The present study describes the tribological properties of penetrated-graphite bronze containing micro-sized sulfide under dry conditions. The graphite penetration was carried out by means of roller burnishing. Micro shot peening was also applied in order to fabricate micro dimples in the penetrated graphite. The graphite area fraction was approximately 50%. The tribological properties were evaluated using a face-to-face type testing apparatus under dry conditions. The results showed that the friction coefficient of the sulfide-containing bronze decreased and the seizure resistance properties significantly increased. The friction distance until seizure occurrence was improved to more than 2.5 times. Furthermore, the friction coefficient was low and stable until the end of the experiment. It was inferred that the friction resistance was decreased and stabilized when the transfer layer was without Fe content.

In order to clarify the plastic deformation mechanism of silicon carbide in cubic phase (3C-SiC), molecular dynamics (MD) simulations are performed on the nanoindentation using a spherical indenter. Transition from elastic deformation to plastic deformation has been confirmed by the phenomenon called pop-in in the load-displacement curves during nanoindentation. Dislocations on {1 1 1} slip planes are found during indentation. In order to analyze internal defects, common neighbor analysis (CNA) is slightly modified so that it is suitable for the analysis of slips of zinc-blend structure. In our method, the CNA is applied separately to sub-lattice of Si or C in the same SiC. By this method, structural changes are confirmed in a region with the shape of square pyramid when the pop-in behavior occurs. By measuring the atomic distances along the region of misalignment, it was confirmed that there is certainly atomic sliding by crystalline slip. Furthermore, it is found that, with increase of loading, dislocation loops spread along {1 1 1} slip planes.

The present study describes the tribological properties of a bronze alloy used as a sliding interface for operation under dry conditions. Many industrial slide bearings are made from bronze alloy. To achieve easy running-in and enhanced anti-seizure, solid lubricants are added to the alloys. However, it is difficult to simultaneously achieve easy running-in and anti-seizure with one solid lubricant. Thus, the combined effects of a solid lubricant and a dispersed sulfide layer on reducing and stabilizing the friction coefficient were also examined. The tribological properties of the resulting alloy were evaluated with a 3-ball on disc type testing apparatus under dry conditions and in air atmosphere. The surface state of the solid lubricant and dispersed sulfide layer was evaluated by observation of the morphology and phase states via atomic force microscopy. Distinctive features of a phase comprising mixed stiff and soft regular regions on the micrometer scale were observed. These two regular regions are considered to be formed from graphite and sulfide by burnishing. The effect of the dual phase state leads to achievement of both easy running-in and anti-seizure.

A sintered bronze system is applied to plane bearings with some lubricants. A bronze-based, sulfide-dispersed Cu alloy was developed via sintering. Sulfides had some functions, reduction of friction resistance, preventing scoring and seizure. Effects of the developed sulfide-containing bronze were investigated using a journal-type testing apparatus in wet conditions; results indicate that the developed bronze may have some anti-scoring properties.

The inhibition of the hERG potassium channel is closely related to the prolonged QT interval, and thus assessing this risk could greatly facilitate the development of therapeutic compounds and the withdrawal of hazardous marketed drugs. The recent increase in SAR information about hERG inhibitors in public databases has led to many successful applications of machine learning techniques to predict hERG inhibition. However, most of these reports constructed their prediction models based on only one SAR database because the differences in the data format and ontology hindered the integration of the databases. In this study, we curated the hERG-related data in ChEMBL, PubChem, GOSTAR, and hERGCentral, and integrated them into the largest database about hERG inhibition by small molecules. Assessment of structural diversity using Murcko frameworks revealed that the integrated database contains more than twice as many chemical scaffolds for hERG inhibitors than any of the individual databases, and covers 18.2% of the Murcko framework-based chemical space occupied by the compounds in ChEMBL. The database provides the most comprehensive information about hERG inhibitors and will be useful to design safer compounds for drug discovery. The database is freely available at http://drugdesign.riken.jp/hERGdb/.

Summary: The development of cancer is driven not only by genetic mutations but also by epigenetic alterations. Here, we show that TET1-mediated production of 5-hydroxymethylcytosine (5hmC) is required for the tumorigenicity of glioblastoma cells. Furthermore, we demonstrate that chromatin target of PRMT1 (CHTOP) binds to 5hmC. We found that CHTOP is associated with an arginine methyltransferase complex, termed the methylosome, and that this promotes the PRMT1-mediated methylation of arginine 3 of histone H4 (H4R3) in genes involved in glioblastomagenesis, including EGFR, AKT3, CDK6, CCND2, and BRAF. Moreover, we found that CHTOP and PRMT1 are essential for the expression of these genes and that CHTOP is required for the tumorigenicity of glioblastoma cells. These results suggest that 5hmC plays a critical role in glioblastomagenesis by recruiting the CHTOP-methylosome complex to selective sites on the chromosome, where it methylates H4R3 and activates the transcription of cancer-related genes. : The development of cancer is driven not only by genetic mutations but also by chromatin and DNA modification changes. Takai et al. now show that proneural glioblastomas contain high levels of 5hmC and TET1. Production of 5hmC is required for the tumorigenicity of glioblastoma cells. Furthermore, 5hmC recruits the CHTOP-methylosome complex to selective sites on the chromosome, where it methylates H4R3 and activates the transcription of cancer-related genes.

Recently, the fuel consumption improvement by weight saving is required in transportation machine. Therefore, Mg alloy is expected as the alternative material of Al alloy and resin material, because it is the lightest in the practical metals and its specific intensity is high. However, twin crystal deformation occurs easily, and there are the two kinds types (i.e. {1012} and {1011} twin crystal) in that deformation. It has been reported that the {1012} twin crystal has work to relax the stress concentration and the {1011} twin crystal has close relation to fracture. Our aim is to evaluate the kinds and the conditions of those types with AE method. In this study, Mg alloy AZ31 was used, and the AE signals of the alloy were detected in compression, tensile and CT test. After that, the analysis of those signals were done. From the results obtained under this experimental conditions, the following things became clear. (1) The frequency components near 250, 550 and 850 kHz are caused by slip, twin crystal deformation and crack growth respectively. (2) It is possible that the two kinds crystal deformation types are discriminated by the identification standards decided by the AE count and fractal dimension Fd of the detected signals.

Sintered materials are commonly used in industrial equipment, including bearing components. These materials include bimetals consisting of steel backed sintered bronze lined bushings. In particular, 90Cu-10Sn (mass%) bronze is widely used in bearing components. Lead bronze, in which the lead serves as a solid lubricant, is being replaced with other materials, among which are sulfide-dispersed bronzes. In sulfide-dispersed bronze, sulfides instead of lead play the role of solid lubricant. However, the sulfides in the bronze may be subject to chemical reduction during sintering, especially when this is carried out under a reducing atmosphere containing hydrogen gas. In this study, we investigate the effect of the sulfides on the bronze, with a focus on the hardness of the bronze matrix and the reaction between sulfides and hydrogen gas. Water-atomized powders were prepared for comparison of the sintering behavior. The sintering temperature in the tests was 1123 K. From the phase diagram of the Cu-Sn system, the liquid phase starts to form into bronze containing 20 mass% Sn at approximately 1123 K; thus, some conditions undergo liquid-phase sintering. Sulfides are observed to disappear from sintered bronze surfaces under a reducing atmosphere. However, the sulfides that are not in a solid solution do not affect the hardness of the bronze matrix, which does, however, depend on the tin content.

The present study describes tribological properties of copper based porous alloy containing nano-sized sulfide particles. The porous alloy was fabricated with sintering on the steel plate using the developed powders consisted from Cu with dispersed sulfides. The micro structure of the alloys consisted from micro sized open pores and sintered particles. The measurement of tribological properties were carried out with a ring on disc testing apparatus with a steel ring as the mating specimen. First, comparison of friction behavior between the developed material and the lead-bronze alloy used as traditional materials for bearings are evaluated. As results, the friction coefficient of the developed material was stable and lower than that of the lead one and larger adhesion resulted in the higher friction resistance was found on the ring surface. In order to enhance porous structure on the reduction and stabilization of the friction resistance, graphite powder was penetrated into the pores by rubbing with the graphite rod. It was found that the further reduction of friction resistance was obtained.

SMA (Shape Memory Alloy) is utilized in various fields. Especially, Ti-Ni alloy has excellent features than other SMA. And, the alloy has two kinds of the phase transformations of rhombohedral (R) and martensitic (M) phase. Though R-phase transformation is not suitable for large deformation, it has been reported that its function for the cyclic deformation is steady. However, the detailed regulation for evaluating the function deterioration and life of the transformations has not been determined, because each factor affects the complexity to each other. Therefore, the establishment of the technique which evaluates the deterioration by the cyclic deformation is desired. In this study, the features of the AE (Acoustic Emission) signals detected in tensile and cyclic deformation test and the structure analysis results of the simulation with MD (Molecular Dynamics) method were compared. As the results, the following things became clear. The frequency components of the signals detected by R- and M-phase were about 750 and 350 kHz respectively. The properties of the signals in each phase showed the chaoticity, and they changed with the increase in the stress. The occurrence behaviors and features of the signals changed with the transitions of the hysteresis loop of σ-ε diagram by cyclic deformation. The generation condition of the R-phase seldom changed in the deformation until rearrangement of R-phase. On the other hand, the conditions on R- and M-phase decreased in the cyclic deformation until M transformation, because the residual phases disturbed the occurrence of M-phase. By observing the simulation results, it was possible to show the existence of the phase transformations of "Austenite (A) phase→R-phase→M-phase" and "A-phase→M-phase". And the correlations between those generation behaviors and the characteristics changes of the signals were recognized.

The bimetal materials that sintered the powder of lead bronze on the base material (i.e. carbon steel) have the excellent performance as the bearing material. However, the nation or the society is moving on with the planning on the use restriction of lead and lead compound. Therefore, lead-free copper alloy is developed, and the practical applications of the alloy are advanced. However, the mechanical properties of the bimetal material that sintered the alloy powder have not sufficiently been grasped. In this study, the evaluation of the fracture mechanism and that types which arose in the materials was examined. As the results, it was possible to grasp or evaluate each fracture type by the frequency component of Acoustic Emission (AE) signal with Fast Fourier Transform (FFT) method, and the m value which is led from the amplitude distribution of the signal. By using the criterion for recognizing each type, it was proven that the proposed technique in this study can evaluate the fracture mechanism of each bimetal material which changed the type of the lining material.