Search

This paper presents a high throughput and low latency wireless with efficient bandwidth transmission, particularly for Medical Internet of Things (MIoT) applications. The proposed method is obtained by employing shorter OFDM (Orthogonal Frequency Divison Multiplexing) symbol duration which corresponds to shorter packet transmission. This can be realized by reducing subcarrier spacing and allowing to use of a smaller number of sample data in the time domain while maintaining sampling rate frequency. Furthermore, the proposed scheme can transmit more data frames twice within the original time slot duration, hence, it can enhance the throughput without expanding the bandwidth utilization. The evaluation results of 20 MHz and 40 MHz bandwidth cases show throughput improvement by around 2.3 and 2.6 times compared to the conventional ones. In addition, the proposed scheme also provides low latency transmission by reducing the transmission time by around 50%. The corresponding hardware implementation is also provided with low-complexity hardware resources. Hence, the proposed system can be used for IoT systems with main considerations on low latency, high throughput, bandwidth efficiency, and low power consumption.

In order to clarify and visualize the real state of the structural performances of ships in operation and establish a more optimal, data-driven framework for ship design, construction and operation, an industry-academia joint R&D project on the digital twin for ship structures (DTSS) was conducted in Japan. This paper presents the major achievements of the project. The DTSS aims to grasp the stress responses over the whole ship structure in waves by data assimilation that merges hull monitoring and numerical simulation. Three data assimilation methods, namely, the wave spectrum method, Kalman filter method, and inverse finite element method were used, and their effectiveness was examined through model and full-scale ship measurements. Methods for predicting short-term extreme responses and long-term cumulative fatigue damage were developed for navigation and maintenance support using statistical approaches. In comparison with conventional approaches, response predictions were significantly improved by DTSS using real response data in encountered waves. Utilization scenarios for DTSS in the maritime industry were presented from the viewpoints of navigation support, maintenance support, rule improvement, and product value improvement, together with future research needs for implementation in the maritime industry.

Lactulose is known to grow health-promoting bacteria, with an increase in the production of beneficial metabolites, such as lactic acid and short-chain fatty acids (SCFAs) in the colon. Ingestion of lactulose powder at a food dosage level is known to reduce the dermal emanation of ammonia, a typical human skin gas which potentially affects body odour. However, no study has reported the effect of lactulose on human skin gases other than ammonia. In this study, the influence of lactulose ingestion on the dermal emissions of γ-lactones, volatile cyclic esters with sweet smells, was investigated in healthy subjects. Healthy participants ingested the lactulose powder with a food dosage of 4 g d−1 once a day for 2 weeks. γ-lactones emanating from the skin surface were collected from each participant’s forearm by using a passive flux sampler, and six kinds of γ-lactones, namely, γ-hexalactone (C6), γ-heptalactone (C7), γ-octalactone (C8), γ-nonalactone (C9), γ-decalactone (C10), and γ-undecalactone (C11), were determined by gas chromatography–mass spectrometry. Quantification of bifidobacteria in faeces collected before and after ingestion of lactulose for 2 weeks was carried out by using real-time PCR. The results showed a significant increase in the dermal emission fluxes of sweet-smelling C10 and C11 lactones as the number of bifidobacteria increased in the faeces, presumably mediated by SCFAs produced in the colon.

Glioblastoma multiforme (GBM) is the most common primary intracranial neoplasm. Although maternal mortality in Japan is among the lowest in the world, the main cause of maternal mortality is pregnancy-related intracranial hemorrhage. This case reports a 30-year-old female pregnant patient who suddenly died at 30 weeks of gestation. She had complained of headache from early stages during pregnancy and reported a headache and stiff neck starting two weeks before her death. Postmortem computed tomography revealed an intracerebral hematoma. The autopsy of the brain revealed severe swelling. The left frontal lobe contained a cavity filled with clear fluid, and a hematoma weighing 24 g. There was also widespread cerebral edema. The histological findings after evaluation of the cavity wall material were indicative of malignancy, and positive immunostaining for alpha thalassemia/mental retardation syndrome X-linked (ATRX), p53 and isocitrate dehydrogenase (IDH-1), was consistent with a diagnosis of GBM. There are studies that indicate pregnancy can promote the clinical and radiological advancement of glioma. The acceleration of tumor growth during pregnancy has been found to depend on several factors (e.g., hormonal factors, growth factors, and hemodynamic changes). Increased cardiac output and blood volume have been shown to promote the size of vascular tumors during pregnancy. Although headaches and neck stiffness are often considered pregnancy-related, this case highlights the importance of its prompt diagnosis, which can also save the fetus’ life. It also emphasizes the need for forensic pathologists to further evaluate intracerebral hematomas identified during investigations of maternal deaths during pregnancy.

Abstract We assessed the positioning accuracy of GNSS-Acoustic (GNSS-A) measurement using a slackly moored buoy. A key feature of real-time buoy-based GNSS-A measurement is that positioning must be performed via single ranging from an arbitrary observation position and encompassing the drifting range of the buoy. In this study, slack-line mooring was employed to resist strong Kuroshio current of up to 5.5 knots in the Nankai Trough. During a year-long sea trial, the buoy drifted within a circle of ~ 4000 m radius, which is much larger than the dimension of a seafloor transponder array. In the sea trial, more than 500 successful regular and on-demand ranging measurements were obtained at various observation positions. The results show that the horizontal positioning accuracy (2σ) of the array for single ranging was 46 cm when the buoy was inside the array and 97 cm when it was outside the array. These accuracies are comparable to those achieved through single ranging in traditional ship-based surveys at the same site. In addition to the distance dependency, we observed directivity in the accuracy, depending on the geometry between an observation point and seafloor transponders. To interpret the accuracy degradation and directivity as a function of observation position, we calculated error ellipses using a dilution-of-precision (DOP) analysis procedure for GNSS-A positioning. The error ellipses clearly illustrate that the variance in array positions is large in the line-of-sight direction from an observation point to the array center. We translated the error ellipses to positioning accuracies using the standard deviation of travel time residuals when an array position is estimated using all pings. The positioning accuracy resulting from the translation corresponded to that obtained using array positions in a buoy observation. The DOP analysis results and their translation into positioning accuracies enabled a detailed assessment of the directional accuracy of GNSS-A positioning at an arbitrary observation position, which is important for real-time measurement of seafloor movement in the event of a huge earthquake.

Oral administration of a low dose of lactulose increases the abundance of genus Bifidobacterium in the large intestine; however, the details of the daily variation in Bifidobacterium have not been researched. To observe how the intestinal microbiota, including Bifidobacterium, change, especially immediately after the initiation of ingestion, we conducted a randomised, placebo-controlled, double-blind crossover study of ingestion of 4 g lactulose/day for 2 weeks in 36 healthy Japanese (including males and females). The primary outcome was the percentage of Bifidobacterium in the faecal bacteria. In the lactulose-treatment group, the percentage of Bifidobacterium was already significantly higher 2 days after starting lactulose ingestion than in the placebo group (20.5 ± 1.2% vs. 17.1 ± 1.2%, p = 0.021). Significant differences were maintained, gradually widening, until the end of the 2-week intervention period. There were significant increases in the percentage and the number of Bifidobacterium with ingestion of 4 g lactulose/day for 2 weeks, but no significant changes in the beta diversity of the intestinal microbiota between lactulose and placebo ingestion. The percentage of Bifidobacterium in the faecal bacteria returned to its original level within a week of the end of intervention with lactulose.

To investigate the relationship between local responsiveness and allergic symptoms, bronchial and nasal responsiveness were measured in the following four groups of subjects: (i) bronchial asthma patients with serum house dust mite (HDM)-specific IgE antibody; (ii) allergic rhinitis patients with serum HDM-specific IgE antibody; (iii) normal control subjects with HDM-specific IgE antibody; and (iv) normal control subjects without IgE antibody specific for 10 common aero-allergens. Bronchial hyperresponsiveness was detected in all subjects with asthma (group 1) and in some subjects from groups 2 and 3, but not in subjects from group 4. Nasal hyperresponsiveness was found in all subjects with allergic rhinitis (group 2) and in some subjects from groups 1 and 3, but not in subjects from group 4. These findings indicate that local hyperresponsiveness of the non-diseased organ is influenced by an individual's atopic status. Interleukin (IL)-4 and IL-5 production by peripheral blood mononuclear cells (PBMC) was measured after stimulation with HDM in groups 1, 2 and 3 and was found to be similar in all three groups. A correlation between bronchial hyperresponsiveness and in vitro cytokine production was noted in asthma patients. These results suggest that the capacity of IL-4 or IL-5 production by PBMC may reflect local hyperresponsiveness in case of asthma.