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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]

Blooms of the harmful algal plankton Chattonella spp. cause severe economic damage to aquaculture. This study aimed to investigate the potential for selective breeding of resistance trait to Chattonella red tides in Japanese yellowtail Seriola quinqueradiata. Two experimental populations were prepared using different production procedures, one was produced by full factorial mating and common rearing tanks, and another was produced by pair mating and family separated rearing tanks. Fingerlings were exposed to mass cultured Chattonella antiqua and their mortality time was recorded as the phenotype of Chattonella resistance. There were significant differences in survival rate among full‐sib families (range 0–50%). Heritability estimates of mortality time were moderate and similar in both populations as 0.329 ± 0.104 and 0.314 ± 0.118 respectively. The environmental variance caused by difference in rearing tanks was relatively small compared with the genetic variance, and had minimal influence on genetic parameter estimation. In contrast, body weight was highly influenced by the environmental variance of rearing tanks, thus heritability estimates varied between populations, 0.275 ± 0.102 and 0.153 ± 0.083 respectively. The genetic correlation between mortality time and body weight was not significant. This is the first report that reveals the contribution of a genetic difference to Chattonella resistance and indicates the potential for selective breeding of Chattonella resistance in Japanese yellowtail. [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]

Post-stroke patients exhibit distinct muscle activation electromyography (EMG) features in sit-to-stand (STS) due to motor deficiency. Muscle activation amplitude, related to muscle tension and muscle synergy activation levels, is one of the defining EMG features that reflects post-stroke motor functioning and motor impairment. Although some qualitative findings are available, it is not clear if and how muscle activation amplitude-related biomechanical attributes may quantitatively reflect during subacute stroke rehabilitation. To better enable a longitudinal investigation into a patient's muscle activation changes during rehabilitation or an inter-subject comparison, EMG normalization is usually applied. However, current normalization methods using maximum voluntary contraction (MVC) or within-task peak/mean EMG may not be feasible when MVC cannot be obtained from stroke survivors due to motor paralysis and the subject of comparison is EMG amplitude. Here, focusing on the paretic side, we first propose a novel, joint torque-based normalization method that incorporates musculoskeletal modeling, forward dynamics simulation, and mathematical optimization. Next, upon method validation, we apply it to quantify changes in muscle tension and muscle synergy activation levels in STS motor control units for patients in subacute stroke rehabilitation. The novel method was validated against MVC-normalized EMG data from eight healthy participants, and it retained muscle activation amplitude differences for inter- and intra-subject comparisons. The proposed joint torque-based method was also compared with the common static optimization based on squared muscle activation and showed higher simulation accuracy overall. Serial STS measurements were conducted with four post-stroke patients during their subacute rehabilitation stay (137 ± 22 days) in the hospital. Quantitative results of patients suggest that maximum muscle tension and activation level of muscle synergy temporal patterns may reflect the effectiveness of subacute stroke rehabilitation. A quality comparison between muscle synergies computed with the conventional within-task peak/mean EMG normalization and our proposed method showed that the conventional was prone to activation amplitude overestimation and underestimation. The contributed method and findings help recapitulate and understand the post-stroke motor recovery process, which may facilitate developing more effective rehabilitation strategies for future stroke survivors. [ABSTRACT FROM AUTHOR]

Sit-to-stand motion is an important daily activity, and it is important to study the mechanism of the motion to improve the ability when it becomes weak. To study the mechanism, we hypothesized that muscle synergy generates muscle activity as a feedforward signal, which is modified by sensory input. This study focuses on determining the sensory input primarily used for modifying sit-to-stand motion. To obtain this, we built artificial neural network models that generate muscle activities based on sensory input and feedforward signals and analyzed the effect of each input on the output. The models were built for each motion phase. The input was information from vestibular and somatosensory input and averaged muscle synergy as feedforward signals, and the output was muscle synergy. As a result, it was revealed that humans may primarily use hip angle to bend forward, ankle and vertical foot reaction force to hip rise, ankle, knee, and lumber angles and vertical foot reaction force to extend body, and lumber angle to stabilize. This indicates the type of sensory input used to control each muscle synergy in each motion phase. The information should be used to modify the sit-to-stand motion in environmental conditions where the motion is performed. [ABSTRACT FROM AUTHOR]

Patients with stroke experience declined physical functions and aim to recover by rehabilitation. It is important to improve their functions in the subacute period. Hemiplegic patients who can stand exhibit differing characteristics such as the center of mass and muscle synergy compared to healthy subjects. However, the characteristics to be achieved by the sit-to-stand motion in the subacute period is unknown. This study investigated the sit-to-stand motions of hemiplegic patients (n = 21) in three months of stroke onset. The patients were partitioned into two groups ('mild' and 'severe'), based on the functional independence score at the time of discharge, and the patient's sit-to-stand motion in the subacute period was analyzed by muscle synergy and kinematics. The severe patients performed a biased standing on the non-paralyzed side, and the activation timing of muscle synergy that contributes to whole-body extension was earlier than that of the mild patients. This study contributes to the development of guidelines for optimal intervention for each patient. [ABSTRACT FROM AUTHOR]

Many patients suffer from declined motor abilities after a brain injury. To provide appropriate rehabilitation programs and encourage motor-impaired patients to participate further in rehabilitation, sufficient and easy evaluation methodologies are necessary. This study is focused on the sit-to-stand motion of post-stroke patients because it is an important daily activity. Our previous study utilized muscle synergies (synchronized muscle activation) to classify the degree of motor impairment in patients and proposed appropriate rehabilitation methodologies. However, in our previous study, the patient was required to attach electromyography sensors to his/her body; thus, it was difficult to evaluate motor ability in daily circumstances. Here, we developed a handrail-type sensor that can measure the force applied to it. Using temporal features of the force data, the relationship between the degree of motor impairment and temporal features was clarified, and a classification model was developed using a random forest model to determine the degree of motor impairment in hemiplegic patients. The results show that hemiplegic patients with severe motor impairments tend to apply greater force to the handrail and use the handrail for a longer period. It was also determined that patients with severe motor impairments did not move forward while standing up, but relied more on the handrail to pull their upper body upward as compared to patients with moderate impairments. Furthermore, based on the developed classification model, patients were successfully classified as having severe or moderate impairments. The developed classification model can also detect long-term patient recovery. The handrail-type sensor does not require additional sensors on the patient’s body and provides an easy evaluation methodology. [ABSTRACT FROM AUTHOR]

The sit-to-stand motion is a common movement in daily life and understanding the mechanism of the sit-to-stand motion is important. Our previous study shows that four muscle synergies can characterize the sit-to-stand motion, and they have specific roles, such as upper body flexion, rising from a chair, body extension, and posture stabilization. The time-varying weight of these synergies are changed to achieve adaptive movement. However, the relationship between sensory input and the activation of the muscle synergies is not completely understood. In this paper, we aim to clarify how vestibular and visual inputs affect the muscle synergy in sit-to-stand motion. To address this, we conducted experiments as follows. Muscle activity, body kinematics, and ground reaction force were measured for the sit-to-stand motion under three different conditions: control, visual-disturbance, and vestibular-disturbance conditions. Under the control condition, the participants stood without any intervention. Under the visual-disturbance condition, the participants wore convex lens glasses and performed the sit-to-stand motion in a dark room. Under the vestibular-disturbance condition, a caloric test was performed. Muscle synergies were calculated for these three conditions using non-negative matrix factorization. We examined whether the same four muscle synergies were employed under each condition, and the changes in the time-varying coefficients were determined. These experiments were conducted on seven healthy, young participants. It was found that four muscle synergies could explain the muscle activity in the sit-to-stand motion under the three conditions. However, there were significant differences in the time-varying weight coefficients. When the visual input was disturbed, a larger amplitude was found for the muscle synergy that activated mostly in the final posture stabilization phase of the sit-to-stand motion. Under vestibular-disturbance condition, a longer activation was observed for the synergies that extended the entire body and led to posture stabilization. The results implied that during human sit-to-stand motion, visual input has less contribution to alter or correct activation of muscle synergies until the last phase. On the other hand, duration of muscle synergies after the buttocks leave are prolonged in order to adapt to the unstable condition in which sense of verticality is decreased under vestibular-disturbance. [ABSTRACT FROM AUTHOR]

Seriola quinqueradiata (yellowtail) is the most widely farmed and economically important fish in aquaculture in Japan. In this study, we used the genome of haploid yellowtail fish larvae for de novo assembly of whole-genome sequences, and built a high-quality draft genome for the yellowtail. The total length of the assembled sequences was 627.3 Mb, consisting of 1,394 scaffold sequences (>2 kb) with an N50 length of 1.43 Mb. A total of 27,693 protein-coding genes were predicted for the draft genome, and among these, 25,832 predicted genes (93.3%) were functionally annotated. Given our lack of knowledge of the yellowtail digestive system, and using the annotated draft genome as a reference, we conducted an RNA-Seq analysis of its three digestive organs (stomach, intestine and rectum). The RNA-Seq results highlighted the importance of certain genes in encoding proteolytic enzymes necessary for digestion and absorption in the yellowtail gastrointestinal tract, and this finding will accelerate development of formulated feeds for this species. Since this study offers comprehensive annotation of predicted protein-coding genes, it has potential broad application to our understanding of yellowtail biology and aquaculture. [ABSTRACT FROM AUTHOR]

Benedenia infections caused by the monogenean fluke ectoparasite Benedenia seriolae seriously impact marine finfish aquaculture. Genetic variation has been inferred to play a significant role in determining the susceptibility to this parasitic disease. To evaluate the genetic basis of Benedenia disease resistance in yellowtail (Seriola quinqueradiata), a genome-wide and chromosome-wide linkage analyses were initiated using F1 yellowtail families (n = 90 per family) based on a high-density linkage map with 860 microsatellite and 142 single nucleotide polymorphism (SNP) markers. Two major quantitative trait loci (QTL) regions on linkage groups Squ2 (BDR-1) and Squ20 (BDR-2) were identified. These QTL regions explained 32.9–35.5% of the phenotypic variance. On the other hand, we investigated the relationship between QTL for susceptibility to B. seriolae and QTL for fish body size. The QTL related to growth was found on another linkage group (Squ7). As a result, this is the first genetic evidence that contributes to detailing phenotypic resistance to Benedenia disease, and the results will help resolve the mechanism of resistance to this important parasitic infection of yellowtail. [ABSTRACT FROM AUTHOR]

Background: Severe aortic valve stenosis is relatively more prevalent in patients with repeated bleeding episodes. The goal of the present study was to determine the effect of aortic valve replacement on von Willebrand factor levels in patients with aortic stenosis. Methods: Von Willebrand factor levels were assessed by using immunoblotting electrophoresis techniques before and 1 month after surgery in 29 consecutive patients with severe aortic valve stenosis. Results: Eight of 29 patients reported episodes of bleeding, including three episodes of major bleeding, in the 6 months before surgery. None of the patients were receiving anticoagulation therapy. Although there was no difference in platelet count before and after surgery, von Willebrand factor levels were significantly greater at 1 month after surgery (p = 0.05) when compared with preoperative values. Further, von Willebrand factor levels were significantly lower in patients with aortic valve prosthesis mismatch than in those patients without this phenomenon (p < 0.05). Electrophoresis experiments showed a deficit in large multimers of von Willebrand factor preoperatively but not postoperatively, except for in those patients with aortic valve prosthesis mismatch. Conclusions: In conclusion, valve replacement can result in increases in von Willebrand factor in patients with aortic valve stenosis. [Copyright &y& Elsevier]

Susceptibility to audiogenic seizures, which are reflex seizures provoked by loud noise, can be induced in rodents by acoustic priming (exposing animals to strong auditory stimuli at an early developmental stage). Some strains of mice and rats are susceptible to audiogenic seizures without priming and these have been used as good experimental models with which to study epilepsies. Here we identifiedVlgr1dandVlgr1e, novel alternatively-spliced variants ofVlgr1b/ MGR1, which, upon sequence analysis, were shown to be transcripts from a locus previously characterized as mass1.Vlgr1(Vlgr1b, Vlgr1dandVlgr1e) mRNA is expressed predominantly in the neuroepithelium of the developing mouse brain. Our protein-tagged experiment suggested that Vlgr1d and Vlgr1e are secretory molecules, while Vlgr1b is a receptor. Knockout mice lacking exons 2–4 ofVlgr1were susceptible to audiogenic seizures without priming, although there were no apparent histological abnormalities in their brains. Ninety-five percent of these knockout mice exhibited wild running, a feature typical of the preconvulsive phase of audiogenic seizures triggered by loud noise (11 kHz, 105 dB), and 68% exhibited tonic convulsions at 3 weeks after birth. Our monogenic mice, which have a unique genetic background, serve as a useful tool for further studies on seizures. [ABSTRACT FROM AUTHOR]

ABSTRACT Olmesartan medoxomil is a new orally active angiotensin II (Ang II) type 1 receptor antagonist. It is a prodrug and is rapidly de-esterified during absorption to form olmesartan, the active metabolite. Olmesartan is a potent, competitive and selective Ang II type 1 receptor antagonist. Olmesartan is not metabolized by the cytochrome P-450 and has a dual route of elimination, by kidneys and liver. In patients with essential hypertension olmesartan medoxomil administered once daily at doses of 10-80 mg dose-dependently reduced diastolic blood pressure (DBP). Troughto-peak ratios for both DBP and systolic blood pressure (SBP) were above 50%. At the recommended once-daily starting doses, olmesartan medoxomil (20 mg) was more effective than losartan (50 mg), valsartan (80 mg) or irbesartan (150 mg) in reducing cuff DBP in patients with essential hypertension. The results of cuff SBP and mean 24-h DBP and SBP were similar to those of cuff DBP measurement. In mild-to-moderate hypertensive patients the recommended starting dose of olmesartan medoxomil was as effective as that of amlodipine besylate (5 mg/day) in reducing both cuff and 24-h blood pressure. In lowering DBP olmesartan medoxomil, at 10-20 mg/day, was as effective as atenolol at 50-100 mg/day. In mild-to-moderate hypertensive patients, olmesartan medoxomil, at 5-20 mg once daily, was more effective than captopril at 12.5-50 mg twice daily. At 20-40 mg once daily olmesartan medoxomil was as effective as felodipine, at 5-10 mg once daily. Olmesartan medoxomil has minimal adverse effects with no clinically important drug interactions. Animal studies have shown that olmesartan medoxomil provides a wide range of organ protection. Olmesartan medoxomil ameliorated atherosclerosis in hyperlipidemic animals and ameliorated cardiac remodeling and improved survival in rats with myocardial infarction. Olmesartan medoxomil has renoprotective effects in a remnant kidney model and type 2 diabetes models. Future investigation should reveal whether these beneficial effects of olmesartan medoxomil are applicable to human diseases. [ABSTRACT FROM AUTHOR]