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Various nondestructive testing (NDT) methods have been proposed to detect defects inside products. The hammering test is an NDT technique widely used for this purpose. In this test method, a worker judges whether a part is defective or not by listening to the sound after hitting the product with a hammer. Conventional research has shown that a classifier using machine learning can discriminate the hammering data with high accuracy. However, to use these machine learning methods, a lot of samples are needed for learning. In actual industrial situations, it is difficult to collect a lot of samples of defective products. Regarding the hammering test, a machine learning method that can correctly discriminate defective products without sample data has not been proposed. This study aims to construct a system that can correctly discriminate the hammering test data even when there are no defective samples. We propose a method using 'transfer learning.' We conducted case studies to demonstrate the effectiveness of the proposed method using two variants of a brazed product. First, we verified the effectiveness of normal machine learning in a hammering test. In this study, we succeeded in discriminating brazed products, which were not correctly discriminated by the workers. We then applied the proposed method to brazed products. We succeeded in discriminating a variant of the brazed products by transferring the knowledge learned from another variant of the brazed products. [ABSTRACT FROM AUTHOR]

Sit-to-stand motion is an important daily activity, and disability of motion can significantly reduce quality of life. Therefore, it is important to understand the mechanism of sit-to-stand motion in order to prevent such scenarios. The sit-to-stand motion was found to be generated by four muscle groups, through muscle synergy. However, it is unclear how muscle synergy can be controlled. Human sit-to-stand motion may be planned based on body condition before motion. In this study, we aimed to clarify the relationship between body condition and muscle activity during the sit-to-stand motion. Accordingly, we measured the muscle activity when knee movability was disturbed as a condition of body change. We also measured the muscle activity during normal sit-to-stand motion and sit-to-stand motion with disturbed knee movability using surface electromyography. Subsequently, we extracted the muscle synergy from the measured muscle activity and compared the activity levels of muscle synergy. The results revealed that muscle activity contributing to forward bending increased and that contributing to the rise of the hip and stabilization decreased when knee movability was disturbed. These results suggest that humans compensate for disturbed knee movability with forward momentum and bending motion. Moreover, this implies that humans adjust their motion to various environments or body conditions by adjusting the level of forward bending activity. [ABSTRACT FROM AUTHOR]

While minimally invasive cardiac surgery (MICS) has become increasingly popular recently even in the field of cardiovascular surgery, the conventional full median sternotomy is still the main approach to the mediastinum, especially for cases which cannot be applied for MICS or in the facilities where MICS is not performed. It has been known that sternal instability is one of the leading causes of sternal infection after median sternotomy. Therefore, we have sought for an additional product to secure strong sternal stability. Since August in 2018, we used a new type of corrugated plate( Super Fixsorb Wave) which is placed inside the sternum in addition to regular sternal wires for 140 patients who had full median sternotomy. Up to now, we have no complications regarding sternotomy including mediastinitis. We believe that additional use of Super Fixsorb Wave enables firm sternal stability and prevents mediastinitis following full median sternotomy.

Industrial enzymes lipase PS (LPS) and lipase AK (LAK), which originate from Burkholderia cepacia and Pseudomonas fluorescens, respectively, are synthetically useful biocatalysts. To strengthen their catalytic performances, we introduced two mutations into hot spots of the active sites (residues 287 and 290). The LPS_L287F/I290A double mutant showed high catalytic activity and enantioselectivity for poor substrates for which the wild-type enzyme showed very low activity. The LAK_V287F/I290A double mutant was also an excellent biocatalyst with expanded substrate scope, which was comparable to the LPS_L287F/I290A double mutant. Thermodynamic parameters were determined to address the origin of the high enantioselectivity of the double mutant. The ΔΔH ‡ term, but not the ΔΔS ‡ term, was predominant, which suggests that the enantioselectivity is driven by a differential energy associated with intermolecular interactions around Phe287 and Ala290. A remarkable solvent effect was observed, giving a bell-shaped profile between the E values and the log P or ε values of solvents with the highest E value in i-Pr 2 O. This suggests that an organic solvent with appropriate hydrophobicity and polarity provides the double mutant with some flexibility that is essential for excellent catalytic performance.

A 42-year-old woman with a history of old myocardial infarction was admitted to our hospital with complaints of worsening orthopnea. Doppler echocardiography exhibited severe functional mitral valve regurgitation. Because of the tethered mitral valve, we performed mitral valve annuloplasty concomitantly with papillary muscle relocation procedure. The patient recovered well. Postoperative echocardiography had not exhibited recurrent mitral valve insufficiency. Moreover, postoperative left ventricular torsion using 2-dimentional speckle tracking imaging, improved at rest and at peak exercise, and this findings suggest that the reversal of left ventricular remodeling in relocation patients following preserved and connected mitral subvalvular apparatus may result from restoration of the global sequence of left ventricular twist mechanics. The analysis of left ventricular torsion may provide a more comprehensive evaluation of left ventricular mechanics and may help understand the effects of papillary muscle relocation with preserving mitral subvalvular apparatus.