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Aim The present study aimed to examine whether heart rate variability (HRV) indices in depressed patients measured at return to work after sick leave are related to the outcome of reinstatement. Methods This study included 30 workers who took a leave of absence due to major depressive disorder. HRV was measured twice, once when participants left work and another when they returned to work. One month after returning to work, 19 participants continued their original work (successful return group), while 11 failed to perform their original work (unsuccessful return group). HRV indices including high‐ and low‐frequency components (HF and LF) were calculated in three conditions within a session lasting for about 5 minutes, initial rest (Rest), mental task (Task), and rest after task (After), and were compared between the two participant groups. Psychological states were evaluated using Self‐rating Depression Scale and State‐Trait Anxiety Inventory. Results No significant differences were observed in the HRV indices on leaving work between groups. On returning to work, the “unsuccessful return group” exhibited lower HF Rest score, higher HF Task/Rest ratio, and higher LF/HF Rest score than the “successful return group.” Psychological scores improved in both groups. Conclusion These results indicate that autonomic dysregulations revealed by HRV measurement at return to work after a leave of absence in MDD patients were related to the outcome of reinstatement and can serve as useful information for the assessment of the risk of unsuccessful return., Autonomic dysregulations revealed by heart rate variability measurement at return to work after sick leave in depressed patients were related to the outcome of reinstatement and can serve as useful information for the assessment of the risk of unsuccessful return.

Daidai (bitter orange, Citrus aurantium) is characterized by its fresh citrus scent. In Japanese cuisine, its juice is an important ingredient. As tons of industrial waste is obtained while processing the daidai juice, additional utilization of this waste has great social value. In our study, we prepared the essential oil from the waste obtained during daidai juice processing and demonstrated that the oil activates human TRPA1 (hTRPA1). This oil contains 10 types of terpenes, all of which activated hTRPA1 with an EC50 value of 6–167 µM. To our knowledge, this study is the first to show a hTRPA1 activation by five terpenes: linalyl acetate, geranyl acetate, osthole, geranyl propionate, and neryl acetate. Because physiological benefits of TRPA1 agonists, such as enhancement of energy metabolism and promotion of skin barrier recovery, have been reported, the oil could be a promising ingredient for anti-obesity food products and cosmetics. Graphical Abstract Human TRPA1 activation by terpenes contained in the peel of daidai.

Bamboo-derived activated carbon prepared by superheated steam (BAC) exhibited performance for utilization as an electric double layer capacitor (EDLC) electrode. Pore structure and EDLC performances were investigated by comparison with phenol resin-derived activated carbon (MSP-20), which is commercially available and often used for the purpose. The nitrogen adsorption isotherm showed that BAC had a large BET-specific surface area of 1268 g/m2 with a developed pore structure, especially of the mesopore, in comparison with MSP-20. It is considered that inherent ash in bamboo promoted activation, in addition to physical activation by superheated steam. Capacitance per electrode volume (CV) was 52 F/cm3 with BAC. Because the density of BAC is high (0.78 g/cm3) compared with that of MSP-20 (0.58 g/cm3), sufficient CV for usage was obtained, although the capacitance per electrode mass (CM) at 5 mA/cm2 itself of BAC (67 F/g) was lower than that of MSP-20 (126 F/g). With IR drop, the resistance value of BAC (9.7 Ω) was lower than that of MSP-20 (10.5 Ω). Especially, the diffusion resistance of BAC disclosed to be smaller than that of MSP-20. These results indicated that BAC produced by steam activation is a promising material with a pore structure suitable for ion transfer in EDLC.

Large amounts of spent coffee grounds are produced daily and represent a global agricultural waste issue. Therefore, conversion of spent coffee grounds to fine chemicals by microorganisms is an attractive biorefinery approach. The valuable tripeptide, glutathione, because of its antioxidant activity, is typically produced in industrial processes by Saccharomyces cerevisiae. However, S. cerevisiae growth is inhibited by caffeine present in spent coffee grounds. In this report, a caffeine-resistant glutathione-producing yeast Millerozyma farinosa was identified. M. farinosa was originally obtained from miso paste and has not been used previously to produce glutathione. M. farinosa cell growth and cellular glutathione synthesis were enhanced by the addition of a spent coffee grounds extract to the culture medium. The addition also showed two-fold increase in overall glutathione production with an equal cell growth by M. farinosa cultured in artificial seawater because this yeast is salt tolerant.

The adsorption properties of wood carbonized at various temperatures were investigated using a mixed gas containing toluene and α-pinene. Hinoki (Chamaecyparis obtusa) samples carbonized at 500°–1100°C were exposed to gas mixtures of toluene and α-pinene at 20°C. The samples carbonized at 500°–700°C only adsorbed toluene, whereas those carbonized at 800°–1100°C adsorbed both toluene and α-pinene. Analysis of the surface structure of the carbonized wood by nitrogen adsorption at liquid nitrogen temperature indicated that the sample carbonized at 700°C had micropores mainly 0.6 nm in diameter and few mesopores, whereas the samples carbonized at 900°C and 1100°C had mesopores and micropores larger than 0.8 nm in diameter. With the sample carbonized at 700°C, the flat-shaped toluene molecules could probably penetrate into the narrower pores, 0.8 nm in diameter, whereas the bulky globular-shaped α-pinene molecules could not. Carbonization at temperatures higher than 900°C probably enlarged the pore size and thereby reduced the selectivity of adsorption. The results revealed that wood carbonized below activation temperature has a unique flat-pore structure that seems to work as a kind of molecular sieving carbon, successfully removing only the harmful volatile organic compound (VOC), toluene, and leaving behind a pleasant aroma of α-pinene in the atmosphere.

This study examined the effects of contact with wood on the living human body using a physiological index and subjective evaluation. Consecutive blood pressure measurements were used as the physiological index, and sensory evaluation using the semantic differential (SD) method was used for subjective evaluation. Consideration was also given to cases in which materials were cooled and heated as well as kept at room temperature, to eliminate the effects of heat flux due to differences in thermal conductivity between wood and other materials. It was found that contact with wood produced coarse/natural sensations, with no associated increase in systolic blood pressure. Contact with cold wood created subjectively dangerous/uncomfortable but still coarse/natural sensations, also with no associated increase in blood pressure; therefore, there was no correspondence between subjective evaluation and physiological responses. Contact with aluminum kept at room temperature and cold acrylic plastic created flat/artificial and dangerous/uncomfortable sensations, with an associated significant increase in blood pressure; thus, there was a close correlation between subjective evaluation and physiological responses. It was therefore concluded that contact with wood, unlike artificial materials such as aluminum, induces no physiological stress even when kept at room temperature or cooled.

Efforts were made to quantify the impact of visual stimulation from interior wood finishes on the impression of room interiors, using feelings about living activities as indicators. Four types of room interiors with interior wood finishes used in different proportions were simulated. The room interiors were photographed from the same viewpoint. A survey was conducted by interviewing 200 test subjects. As a result of the analysis of principal components, it was found that desires of living activities obtained from the four photographs consisted of two factors: desires for calmness and desires for activities. A great desire for calmness was obtained from photographs showing wood materials. A weak desire for calmness and a strong desire for activities were obtained from a photograph that showed no wood materials. Great desires for both calmness and activities were obtained from a photograph showing wood materials used only as flooring material. As for an evaluation of “living,” the photograph of a room interior without wooden materials was evaluated as a place that test subjects did not feel like living in. The photograph showing wood materials used only as flooring material was evaluated as the place that test subjects most felt like living in, and considered most suitable as a living space.

The effect of visual stimulation from wood on the body was examined in a comparative study using full-sized hinoki wall panels and a white steel wall panel. Continuous blood pressure measurements were used as the physiological indicator. Sensory evaluation by the semantic differential (SD) method and the profile of mood states (POMS) test were performed to determine changes in psychological impression. Results showed that visual stimulation from hinoki wall panels had an emotional and natural impression upon humans. Blood pressure decreased significantly in subjects who liked them, and there was no significant increase in blood pressure in subjects who disliked them. Visual stimulation from the white steel wall panel made an unhealthy and closed impression and increased the sense of depression. In addition, there was stress and a significant increase in blood pressure in subjects who disliked them. Consequently, visual stimulation from hinoki and white steel wall panels had different physiological and psychological effects. Results also showed that the same visual stimulation induced different physiological responses depending on the values of the individuals.

We measured response time, the number of nonresponses, response error, and subjective visibility evaluation for color Landolt-Cs with a gray color background presented on a CRT display to young and old adults (mean ages: 22.3 and 65.9 years, respectively) and to the same young adults wearing glasses with filters simulating an aging human crystalline lens. Comparing the results of elderly and young subjects without the filter, the results of the elderly subjects showed a longer response time, higher nonresponse ratio, slower response speed, and lower visibility, particularly for gray and blue stimuli. Conversely, the results for the young subjects who were fitted with the filters showed tendencies similar to those of the elderly subjects. These results indicate that the yellowing of the human lens strongly influences the visibility of color targets in the elderly and that wearing the filters enables young adults to simulate the visibility of the elderly. It suggests that the simulated filter as well as the aging human lens modifies the effective luminance, effective luminance contrast, and color difference between the color target and the background on the retina. Moreover, the relationship between the subjective evaluation and the response speed changes remarkably with age, regardless of the filters, suggesting that not only the subjective evaluation but also the evaluation of the performance, such as response speed, is important in estimating visibility and controllability in the elderly. The filter used in the present study will be an effective tool for the young to evaluate the visibility of elderly adults in terms of both response speed and subjective evaluation of visibility. © 2004 Wiley Periodicals, Inc. Col Res Appl, 30, 5–12, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/col.20071

A small and light-weight wearable electrocardiograph (ECG) equipment with a tri-axis accelerometer (x, y and z-axis) was developed for prolonged monitoring of everyday stress. It consists of an amplifier, a microcomputer with an AD converter, a triaxial accelerometer, and a memory card. Four parameters can be sampled at 1 kHz for more than 24 h and a maximum of 27 h with a default battery and a memory card of one giga byte (1 GB). Off-line data processing includes motion information along three axes and autonomic nervous system (ANS) activity bispectral analysis and the tone-entropy method (T-E method) from HRV data. The availability of the system was tested through simulated office work and three-day monitoring by replacing the battery and the memory card every 24 h. Both short-term and circadian rhythms of ANS activity were clearly observed. In addition, sympathetic nervous activities gradually increased from the second to the third day. The experimental data presented verifies the functionality of the proposed system.

A small and light-weight wearable electrocardiograph (ECG) equipment with three accelerometers (x, y and zaxis) was developed for prolonged monitoring of autonomic nervous system in daily life. It consists of an amplifier, a bandpass filter, a microcomputer with an AD converter, a triaxial accelerometer, and a memory card. Four parameters can be sampled at 1 kHz (10 bits) for more than 24 hours, maximum 27 hours, with a default battery and a memory card (1 GB). The availability of the system was tested for three subjects for three days by replacing the battery and the memory card every 24 hours under each environment. Both short-term and circadian rhythms of the autonomic nervous system were clearly observed. The change of the autonomic nervous system from body movement (i.e. walking or turning over) was observed by check acceleration data. The feasibility of the application in clinical practice is also discussed.

To elucidate how aging affects the muscular load required for pulling up pants-style disposable diapers, and why some elderly people cannot pull up the rear of their disposable diapers well, we evaluated the electromyogram (EMG) of 8 young subjects (21.5+/-1.5 years) and 7 elderly subjects (71.6+/-6.1 years). EMG was measured for four muscles--biceps brachii, deltoid, brachioradialis, and flexor carpi ulnaris. We evaluated the muscular load during a series of motions for pulling a disposable diaper up at the front and the rear of the body using an EMG-Video Synchronous Split Method. The analysis revealed that the front and the rear integral EMG of elderly subjects were both significantly larger than those of young subjects for all four muscles. For the deltoid and flexor carpi ulnaris muscles, the maximum amplitude of EMG when pulling up the rear of the disposable diapers was significantly larger in the elderly subjects than the young ones. These results suggest that the muscular load involved in pulling up the rear of disposable diapers may increase due to changes in body habitus caused by aging. Since muscular strength decreases with age, it seems likely that the elderly individuals will eventually be unable to pull up the rear of their diapers.

The purpose of the study is to show the feasibility of a light-weight wearable electrocardiograph with three accelero-meters for monitoring stress in everyday life. It consists of an amplifier, a band pass filter, a microcomputer with an AD converter, a triaxial accelerometer, and a memory card. An ECG and three accelerations are sampled at 1 kHz for more than 24 hours, maximum 27 hours with a default battery and a memory card. The heart rate variability analysis program detects R waves and determines R-R intervals for 24 hours by a data acquisition algorithm. An algorithm was also developed. It was designed to reduce motion artifacts induced by body movements on ECG. Autonomic nervous activity levels are calculated based on the heart rate variability spectrum analysis. The availability of the system was tested for three subjects for three days by replacing the battery and memory card every 24 hours under each environment. Both short time rhythms and a circadian rhythm of autonomic nervous system were clearly observed. The feasibility of the system for monitoring the long-term stress level is discussed.

We measured reaction time (RT), P300, and subjective evaluation for color Landolt-Cs with a gray color background presented on a CRT display. Seven young and 7 elderly subjects (mean ages: 21.6 and 68.4 years, respectively) participated, and the young subjects wore glasses with filters simulating spectral transmittance of an aging human lens as a test condition. The results for young subjects not wearing the filters showed that RT and P300 latency are constant among different test colors. In contrast, the results for elderly subjects showed that RT and P300 varied substantially depending upon the test colors and RT and P300 latency became longer than those of young subjects, particularly for gray and blue stimuli. In addition, the results for the young subjects with filters showed tendencies similar to those in elderly subjects. These results indicate that the yellowing of the human lens strongly influences reaction time and cognition time for color targets, suggesting that wearing the filters enables the young to simulate RT qualitatively as well as visibility of the elderly because both the simulated filter and the aging human lens modify the effective luminance, effective luminance contrast and effective color difference between the color target and the background on the retina. We also found that the reciprocal of RT and P300 latency could be expressed in a multiple regression model consisting of effective luminance, effective luminance contrast, effective color difference and age. Absolute values of RT and P300 latency in young subjects with filters, however, did not quantitatively coincide with those of the elderly subjects. There were differences of RT and P300 latency between the young with filters and the elderly, indicating that higher order age-related delay could be involved.

A small and light-weight wearable electrocardiograph (ECG) device with three accelerometers (x, y, and z axis) was developed for prolonged monitoring of everyday stress. It consists of an amplifier, a microcomputer with an analog/digital converter, a tri-axial accelerometer, and a memory card. Four parameters can be sampled at 1 kHz for a maximum of 27 h with the default battery and a 1 GB memory card. An algorithm for the reliable and clear detection of R wave peaks of ECG was also developed for accurate heart rate variability (HRV) analysis. The algorithm reduces ECG motion artifacts induced by body movements. Off-line data processing includes autonomic nervous system (ANS) activity bi-spectral analysis and the application of the tone-entropy method to HRV data. The availability of the system was tested through simulated office work and three-day monitoring. Both short-term and circadian rhythms of ANS activity were clearly observed. The experimental data verifies the functionality of the proposed system.

Reducing pressure is one of the most important factors in preventing decubitus. One way to reduce pressure is to redistribute pressure over as large an area as possible. Soft polyurethane mattresses are good for redistributing pressure, however this type of mattress does not provide sufficient back support. So in order to reduce pressure and provide sufficient support, we have developed a silicone gel layered mattress.Silicone gel is frequently used as a shock absorber in various types of machines and our tests showed that silicone gel was superior to standard polyurethane mattress materials in reducing interface pressure. The silicone gel layered mattress was also preferred by volunteers over a standard hard mattress and a standard soft mattress.

In this study we examined the proper pressure of air boots for a person in a sitting position. Air boots can improve calf congestion by pulsatile calf compression. Higher pressure may improve calf congestion more, though it might decrease arterial blood flow. A photo-electric plethysmometer was put on the second toe of a foot to measure the amplitude of the pulse which represent arterial blood flow. A sensor of a near infrared oxygen monitor was put on the calf just above an air boot. A near infrared oxygen monitor can detect tissue reduced hemoglobin which exists almost only in venous blood. So, the concentration of tissue reduced hemoglobin could represent tissue venous blood concentration.When the air boots pressure was more than 140mmHg, the amplitude of the arterial pulse decreased to half of that without massage. Pressure less than 70mmHg didn't affect arterial blood flow. Meanwhile pressures of more than 70mmHg didn't show any difference in the improvement of calf congestion. So, we concluded that the proper pressure for air boots massage for calf congestion in a sitting position is less than 70mmHg.