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Cervical auscultation is a simple, noninvasive method for diagnosing dysphagia, although the reliability of the method largely depends on the subjectivity and experience of the evaluator. Recently developed methods for the automatic detection of swallowing sounds facilitate a rough automatic diagnosis of dysphagia, although a reliable method of detection specialized in the peculiar feature patterns of swallowing sounds in actual clinical conditions has not been established. We investigated a novel approach for automatically detecting swallowing sounds by a method wherein basic statistics and dynamic features were extracted based on acoustic features: Mel Frequency Cepstral Coefficients and Mel Frequency Magnitude Coefficients, and an ensemble learning model combining Support Vector Machine and Multi-Layer Perceptron were applied. The evaluation of the effectiveness of the proposed method, based on a swallowing-sounds database synchronized to a video fluorographic swallowing study compiled from 74 advanced-age patients with dysphagia, demonstrated an outstanding performance. It achieved an F1-micro average of approximately 0.92 and an accuracy of 95.20%. The method, proven effective in the current clinical recording database, suggests a significant advancement in the objectivity of cervical auscultation. However, validating its efficacy in other databases is crucial for confirming its broad applicability and potential impact. [ABSTRACT FROM AUTHOR]

One of the features of Japanese structural steel design is an economical design option for yielding exposed column bases before first‐story columns, namely weak‐base/strong‐column design, which is unlike the strict capacity design for column bases. This study aims to develop a repair methodology that identifies damage states of the yielding column bases and anchor rods, and selects appropriate repair/retrofit methods. As a standard repair method for damaged exposed‐type column bases, the applicability and effectiveness of the re‐tightening process of anchor rods need to be examined. This study first reviews the literature on standard retrofit techniques for column bases and required deformation capacity of ductile anchor rods. The threaded anchor rod deformation capacity with different steel grades and screw threads commonly used were tested to clarify the required ductility. To clarify the reparability of exposed column bases, numerical models of four‐ and six‐story steel moment resisting frame buildings were developed and validated by shaking table test results. The results show that this simple repair method was proven to be effective through the test program and numerical analysis and it's not always applicable for standard anchor rods assumed for pin or fixed column bases designed to remain elastic. Finlly, a repair methodology and flow chart that identifies the damage states of anchor rods and selects appropriate repair/retrofit methods for the exposed steel column base was suggested and applied to the simulation results. [ABSTRACT FROM AUTHOR]

In Europe, a monopile is the most commonly used foundation type for offshore wind turbines. Existing connections between the monopile (MP) and transition piece (TP) are generally bolts or grout, but another new method is the slip joint. In this method, the joints between the MP and TP are conically shaped and are simply joined together, which is expected to improve workability and reduce maintenance and management costs. In order to apply this structure in Japan, it is necessary to verify its seismic resistance. This paper reports the results of shaking table tests using a scaled specimen to verify the structural safety of the structure against earthquakes. [ABSTRACT FROM AUTHOR]

Few standards and guidelines to prevent health problems have been associated with tablet use. We estimated the effects of posture and tablet tilt angle on muscle activity and posture in healthy young adults. Seventeen healthy young adults (age: 20.5 ± 3 years) performed a cognitive task using a tablet in two posture (sitting and standing) and tablet tilt angle (0 degrees and 45 deg) conditions. Segment and joint kinematics were evaluated using 16 inertial measurement unit sensors. Neck, trunk, and upper limb electromyography (EMG) activities were monitored using 12 EMG sensors. Perceived discomfort, kinematics, and EMG activities were compared between conditions using the Friedman test. The perceived discomfort in the standing-0 deg condition was significantly higher than in the remaining three conditions. Standing posture and tablet inclination significantly reduced the sagittal segment and joint angles of the spine, compared with sitting and flat tablet conditions. Similarly, standing posture and tablet inclination significantly reduced EMG activities of the dorsal neck, upper, and lower trunk muscles, while increasing EMG activity of shoulder flexors. Standing posture and tablet inclination reduced the sagittal flexion angle, and dorsal neck, upper, and lower trunk muscle activities, while potentially increasing the muscle activity of arm flexors. [ABSTRACT FROM AUTHOR]

This is an extension of the companion paper (Part 1) that presents the details of the two buildings located in Tokyo and designed using the US Performance Based Seismic Design (PBSD) methodology for one building (US Prototype Building) and the Japanese PBSD methodology for the other (Japan Prototype Building). The paper presents the IDA results and associated discussion on the collapse safety margin and the damage progress of the major structural elements. The Japan Prototype Building made of steel moment-resisting frames equipped with oil dampers is 1.5 times stronger in terms of the collapse safety margin than the US Prototype Building made of an reinforced concrete (RC) core shear wall system. The difference between the two buildings is believed to occur because of the larger redundancy and resultant larger over-strength achieved by the Japan Prototype Building. It is noteworthy that the construction cost of the Japan Prototype Building is about 30% higher than the US Prototype Building as indicated in Part 1. To explain the behavioral difference, sequences, and progresses of damage to major structural members are characterized in reference to the fragility curves of respective members. The benefits of oil dampers are found that the addition of the oil dampers would increase the collapse safety margin by 29% with an extra construction cost of 3%. [ABSTRACT FROM AUTHOR]

Performance-based seismic analysis and design of tall buildings have become increasingly common in the United States and have been the standard practice in Japan for a long time. The methodologies for seismic hazard analyses, selection of earthquake records for design, and acceptance criteria, however, are widely different in the two countries. Japan experiences large earthquakes and strong shakings of buildings significantly more frequently than the United States, and the data on actual seismic performance are richer in Japan than in the United States. Comparison of performance and calibration between the two design procedures can help to improve the quantitative assessment of seismic performance of buildings in the United States. This article presents the application of US and Japanese procedures to a tall building archetype once proportioned, analyzed, and designed according to US practices and once per Japanese practices. The structural systems selected are very different; for the United States, the archetype is designed using a core reinforced concrete shear wall building with composite floor systems and steel columns as the gravity system, whereas for Japan, the archetype is designed using a steel moment frame made of square concrete-filled steel tube (CFT) columns and composite beams and installed with oil dampers. Although the design procedures followed are vastly different, the seismic performances of the systems are rather similar during serviceability, design basis, and maximum considered events. As will be presented in the second part of this article, the collapse safety margins of the two designs are significantly different. [ABSTRACT FROM AUTHOR]

Choosing friction pendulum isolators to avoid problems with device displacement capacity or boundary wall collision is a critical part of the seismic design of base isolation systems. This paper developed a probabilistic method to quantify the risk of failure in single friction pendulum bearing (FPB) devices. This was done by calibrating a demand‐intensity model for FPBs from numerical analysis for several device property combinations. These properties encompassed the dynamic friction coefficient and effective radius of curvature—key parameters impacting these FPB devices' seismic response. Through this demand‐intensity model, a closed‐form and relatively simple approach to quantify the mean annual frequency of exceeding a given device displacement threshold, or risk of failure, was proposed. By applying this simplified method to several case study structures and comparing it with a more extensive assessment involving multiple stripe analysis (MSA) using hazard‐consistent ground motions, the proposed simplified approach could provide very accurate estimates of displacement‐based failure risk in FPB devices under the assumption of no non‐linear behaviour in the superstructure. This proposed approach implies that structural engineers can now quickly assess the actual failure rates of different FPB device combinations used in practice to give a more uniform level of safety or reliability when designing and assessing FPB‐isolated systems. It is also arguably much simpler, direct and accurate than currently available code‐based approaches. [ABSTRACT FROM AUTHOR]

Neck pain is one of the most common musculoskeletal complaints. Evidence suggests that increased activities of neck and trunk muscles are one of the mechanisms related to neck pain. Jaw clenching and sitting posture may modulate the muscle activity in neck and trunk muscles during typing. The present study aimed to assess the effects of different postural positions and clenching conditions on neck and trunk muscle activities. Thirteen healthy adults (39.8 ± 5.0 years) performed computer typing tasks in four conditions (two postural positions [upright vs slouched] and two jaw clenching conditions [clenching vs non‐clenching]). Integrated surface electromyography (iEMG) was measured in sternocleidomastoid (SCM), upper trapezius (uTP) and middle trapezius (mTP) muscles and compared between conditions. The Friedman and Wilcoxon signed‐rank tests with Bonferroni's corrections were used to estimate the condition‐specific differences in the iEMG data. The statistical significance level was set at 5%. In both postural positions, iEMGSCM was significantly greater under the jaw clenching than under the non‐clenching condition (χ2 = 21.700, P <.01). Under both jaw clenching conditions, iEMGuTP was significantly greater in the slouched than in the upright postural position (χ2 = 23.182, P <.01). No significant differences in iEMGmTP were seen across conditions (χ2 = 5.018, P =.10). Sitting posture and jaw clenching appear to influence activities of different muscles. [ABSTRACT FROM AUTHOR]

In Japan, structural health monitoring (SHM) of building structures began in the 1950s, but, until recently, its widespread use was not realized. A new trend arrived a few years ago, and currently over 850 buildings have SHM systems installed. The most recent SHM systems have been installed voluntarily by owners in the private sector; that is, the major development of recent Japanese SHM has been based on market forces. This article reports on why SHM was not accepted widely in the past, what were the keys for change of the atmosphere, how the building owners evaluate SHM after it is deployed, and what tangible benefits the building owners realize by experience on SHM implementation. To investigate those, an SHM system named q-NAVI is introduced as an example. The system has been deployed for 450 buildings, and they experienced a few significant shakings from recent earthquakes. SHM is also found effective for acquiring information on the quantification of fragility curves for various nonstructural components, using the data samples collected in recent earthquakes. [ABSTRACT FROM AUTHOR]

Background: Neuroleptic drug-induced parkinsonism (NIP) is a leading cause of parkinsonism, particularly in aging. Based on abnormal dopamine transporter scan results, individuals displaying chronic NIP are often diagnosed with Lewy-body Parkinson's disease (PD), but this assumption needs further substantiation.Objective: To quantitate the profile of striatal dopaminergic nerve terminal density in NIP relative to PD.Methods: We used the positron emission tomography ligand [11 C](+)-dihydrotetrabenazine targeting vesicular monoamine transporter type 2 (VMAT2) binding sites and collected various clinical parameters (motor ratings, olfaction, polysomnography to document rapid eye movement sleep muscle activity, quantitative sensory testing for pain thresholds) possibly predicting binding results in patients older than age 50 living with schizophrenia spectrum disorders under long-term stable antipsychotic drug treatment, with (N = 11) or without (N = 11) chart documention of chronic NIP, and compared them to healthy volunteers (N = 11) and others medicated for PD (N = 12).Results: Striatal VMAT2 binding was dichotomous in the NIP group between those with spared (N = 5) or low (N = 6) PD-like values. Striatal binding reduction in the low VMAT2-NIP group was asymmetric without the gradient of maximal involvement in the posterior putamen typical of PD. Anosmia was the only nonmotor parameter measured matching the abnormal striatal VMAT2 binding status.Conclusion: These preliminary observations suggest that striatal VMAT2 binding is abnormal in a fraction of chronic NIP cases and differs in spatial distribution from PD. The possibility of a drug-induced axonopathy and resultant synaptopathy, as well as the evolution of the binding deficit, warrant further longitudinal studies in a large cohort. © 2020 International Parkinson and Movement Disorder Society. [ABSTRACT FROM AUTHOR]

Objective: This study aims to verify the associations among sleep bruxism (SB), sleep arousal (SA) and concurrent body movements. Material and Methods: Subjects underwent a standard overnight polysomnography test and audio‐video recordings. Sleep quality was evaluated according to the Rechtschaffen and Kales criteria, while SA was determined as per the American Sleep Disorders Association criteria. Analyses were performed by an external institution after masking of the subjects' information. SB was assessed based on the presence/absence of rhythmic masticatory muscle activity (RMMA) episodes, which were identified by using electromyography of the masseter muscle. The observed simultaneous movements included lower leg movement (LLM), swallowing, face scratching, head movement, body movement, eye blinking, coughing, licking, sighing, body scratching, lip sucking, somniloquy and yawning. The LLM was determined visually, as well as through an increase in the tibialis electromyogram signal. Other movements were visually assessed using audio‐video recordings. The incidences of all the simultaneous movements were compared between RMMA with intercurrent SA (SAwRMMA; RMMA episode derived from a masseter electromyogram showing more than 10% of maximum voluntary contraction) and SA without RMMA (SAw/oRMMA). Results: Fourteen subjects were included in this study (females/males: 4/10, mean age: 31.5 ± 5.7 years). Among these, LLM, swallowing, body movement, licking, body scratching and lip sucking were frequently observed in SAwRMMA episodes than in SAw/oRMMA episodes, significantly. However, the non‐specific simultaneous movements were higher observed in SAw/oRMMA episodes than that in SAwRMMA. Conclusion: Our results suggest that SB is concurrently activated with LLM in relation to arousal. [ABSTRACT FROM AUTHOR]