Age-Friendly Ecosystems: Expert Voices from the Field.

(1) Background: With the growth of the age-friendly movement, age-friendly ecosystems (AFE) garnered more attention. The successful development of an AFE is contingent on unified efforts across different stakeholders; however, limited efforts were made to help create a common understanding of the necessary components of an AFE. (2) Methodology: In response, The John A. Hartford Foundation and The Age-Friendly Institute hosted a series of convenings of international experts to identify a working definition of the characteristics composing an AFE. The goal of these convenings was to provide a foundation on which to unite cross-sector age-friendly work. (3) Results: This paper discussed the findings of the convenings and provided a framework from which future age-friendly work must draw upon. (4) Conclusions: This paper presented a necessary change in how we conceive AFEs.

Deep learning-based robust automatic non-invasive measurement of blood pressure using Korotkoff sounds.

This paper proposes a method that automatically measures non-invasive blood pressure (BP) based on an auscultatory approach using Korotkoff sounds (K-sounds). There have been methods utilizing K-sounds that were more accurate in general than those using cuff pressure signals only under well-controlled environments, but most were vulnerable to the measurement conditions and to external noise because blood pressure is simply determined based on threshold values in the sound signal. The proposed method enables robust and precise BP measurements by evaluating the probability that each sound pulse is an audible K-sound based on a deep learning using a convolutional neural network (CNN). Instead of classifying sound pulses into two categories, audible K-sounds and others, the proposed CNN model outputs probability values. These values in a Korotkoff cycle are arranged in time order, and the blood pressure is determined. The proposed method was tested with a dataset acquired in practice that occasionally contains considerable noise, which can degrade the performance of the threshold-based methods. The results demonstrate that the proposed method outperforms a previously reported CNN-based classification method using K-sounds. With larger amounts of various types of data, the proposed method can potentially achieve more precise and robust results.

Investigation on the Printed CNT-Film-Based Electrochemical Sensor for Detection of Liquid Chemicals.

We studied electrochemical sensors using printed carbon nanotubes (CNT) film on a polyethylene telephtalate (PET) substrate. The mechanical stability of the printed CNT film (PCF) was confirmed by using bending and Scotch tape tests. In order to determine the optimum sensor structure, a resistance-type PCF sensor (R-type PCF sensor) and a comb-type PCF sensor (C-type PCF sensor) were fabricated and compared using a diluted NH3 droplet with various concentrations. The magnitude of response, response time, sensitivity, linearity, and limit of detection (LOD) were compared, and it was concluded that C-type PCF sensor has superior performance. In addition, the feasibility of PCF electrochemical sensor was investigated using 12 kinds of hazardous and noxious substances (HNS). The detection mechanism and selectivity of the PCF sensor are discussed.

Machine Learning Approach to find the relation between Endometriosis, benign breast disease, cystitis and non-toxic goiter.

The exact mechanism of endometriosis is unknown. The recommendation system (RS) based on item similarities of machine learning has never been applied to the relationship between diseases. The study aim was to identify diseases associated with endometriosis by applying RS based on item similarities to insurance data in South Korea. Women aged 15 to 45 years extracted from the Korean Health Insurance Review & Assessment Service National Inpatient Sample (HIRA-NIS) 2009-2015. We used the RS model to extract diseases that were correlated with an endometriosis diagnosis. Among women aged 15 to 45 years, endometriosis was defined as a diagnostic code of N80.x and a concurrent treatment code. A control group was defined as women who did not have the N80.x code. Benign breast diseases, cystitis, and non-toxic goitre were extracted by the RS. A total of 1,730,562 women were selected as the control group, and 11,273 women were selected as the endometriosis group. In logistic regression analysis adjusted for age per 5 years, data year, and socioeconomic status, benign neoplasm of breast (odds ratio (OR): 2.58; 95% confidence interval (CI): 1.90-3.50), other cystitis (OR: 2.63; 95% CI: 1.56-4.44), and non-toxic single thyroid nodule (OR: 1.62; 95% CI: 1.14-2.32) were statistically significant. Endometriosis was associated with benign breast disease, cystitis, and non-toxic goitre.

Noise and Room Acoustic Conditions in a Tertiary Referral Hospital, Seoul National University Hospital.

BACKGROUND AND OBJECTIVES: Noise levels and room acoustic parameters at a tertiary referral hospital, Seoul National University Hospital (SNUH) in Korea, are investigated. MATERIALS AND METHODS: Through a questionnaire, acoustically problematic rooms are identified. Noise levels in emergency rooms (ERs) and intensive care units (ICUs) are measured over about three days. Acoustically critical and problematic rooms in the otolaryngology department are measured including examination rooms, operating rooms, nurse stations, receptions, and patient rooms. RESULTS: The A-weighted equivalent noise level, LAeq, ranges from 54 to 56 dBA, which is at least 10 dB lower than the noise levels of 65 to 73 dBA measured in American ERs. In an ICU, the noise level for the first night was 66 dBA, which came down to 56 dBA for the next day. The noise levels during three different ear surgeries vary from 57 to 62 dBA, depending on the use of surgical drills and suctions. The noise levels in a patient room is found to be 47 dBA, while the nurse stations and the receptions have high noise levels up to 64 dBA. The reverberation times in an operation room, examination room, and single patient room are found to be below 0.6 s. CONCLUSIONS: At SNUH, the nurse stations and receptions were found to be quite noisy. The ERs were quieter than in the previous studies. The measured reverberation times seemed low enough but some other nurse stations and examination rooms were not satisfactory according to the questionnaire.

An early report: a modified porphyrin-linked metronidazole targeting intracellular Porphyromonas gingivalis in cultured oral epithelial cells.

Porphyromonas gingivalis (P. gingivalis) has a strong association with the pathogenesis of periodontal disease. Recurrence of periodontal disease following therapy is attributed to numerous factors, and of growing interest is the potential problem of intracellular bacteria that are able to persist and multiply within the host cell, thereby facilitating relapse of infection. The effect of antibiotic therapy in controlling P. gingivalis is questionable. Accordingly, while metronidazole is very effective against anaerobic extracellular P. gingivalis by disrupting the DNA of anaerobic microbial cells, this antibiotic does not effectively penetrate into mammalian cells to inhibit intracellular bacteria. Therefore in the present study, a modified porphyrin-linked metronidazole adducts, developed in our laboratory, was used to kill intracellular P. gingivalis. A series of experiments were performed, including cytotoxicity assays and cellular uptake of adducts by flow cytometry coupled with live cell imaging analysis, P. gingivalis invasion and elimination assays, and the analysis of colocalization of P. gingivalis and porphyrin-linked metronidazole by confocal laser scanning microscopy. Findings indicated that P. gingivalis and porphyrin-linked metronidazole were colocalized in the cytoplasm, and this compound was able to kill P. gingivalis intracellular with a sufficient culture time. This is a novel antimicrobial approach in the elimination of P. gingivalis from the oral cavity.

Frequency Mixing Magnetic Detection Scanner for Imaging Magnetic Particles in Planar Samples.

The setup of a planar Frequency Mixing Magnetic Detection (p-FMMD) scanner for performing Magnetic Particles Imaging (MPI) of flat samples is presented. It consists of two magnetic measurement heads on both sides of the sample mounted on the legs of a u-shaped support. The sample is locally exposed to a magnetic excitation field consisting of two distinct frequencies, a stronger component at about 77 kHz and a weaker field at 61 Hz. The nonlinear magnetization characteristics of superparamagnetic particles give rise to the generation of intermodulation products. A selected sum-frequency component of the high and low frequency magnetic field incident on the magnetically nonlinear particles is recorded by a demodulation electronics. In contrast to a conventional MPI scanner, p-FMMD does not require the application of a strong magnetic field to the whole sample because mixing of the two frequencies occurs locally. Thus, the lateral dimensions of the sample are just limited by the scanning range and the supports. However, the sample height determines the spatial resolution. In the current setup it is limited to 2 mm. As examples, we present two 20 mm × 25 mm p-FMMD images acquired from samples with 1 µm diameter maghemite particles in silanol matrix and with 50 nm magnetite particles in aminosilane matrix. The results show that the novel MPI scanner can be applied for analysis of thin biological samples and for medical diagnostic purposes.

Reproduction of nearby sources by imposing true interaural differences on a sound field control approach.

In anechoic conditions, the Interaural Level Difference (ILD) is the most significant auditory cue to judge the distance to a sound source located within 1 m of the listener's head. This is due to the unique characteristics of a point source in its near field, which result in exceptionally high, distance dependent ILDs. When reproducing the sound field of sources located near the head with line or circular arrays of loudspeakers, the reproduced ILDs are generally lower than expected, due to physical limitations. This study presents an approach that combines a sound field reproduction method, known as Pressure Matching (PM), and a binaural control technique. While PM aims at reproducing the incident sound field, the objective of the binaural control technique is to ensure a correct reproduction of interaural differences. The combination of these two approaches gives rise to the following features: (i) an accurate reproduction of ILDs is achieved at the head positions considered by the method, (ii) the ILD variations in the vicinity of those positions are smoothed, thus lowering the ILD error, and (iii) the true wavefront is preserved. Given the properties of the presented method, intended distance and directional perception is expected.

Development of waterborne oil spill sensor based on printed ITO nanocrystals.

Oil spill accidents occasionally occur in coastal and ocean environments, and cause critical environmental damage, spoiling the marine habitats and ecosystems. To mitigate the damages, the species and amount of spilled oil should be monitored. In this study, we developed a waterborne oil spill sensor using a printed ITO layer. ITO is a compatible material for salty environments such as oceans because ITO is strong against corrosion. The fabricated sensor was tested using three oils, gasoline, lubricant and diesel, and different oil thicknesses of 0, 5, 10, and 15mm. The results showed that the resistance of the sensor clearly increased with the oil thickness and its electrical resistance. For sustainable sensing applications in marine environments, XRD patterns confirmed that the crystal structure of the ITO sensor did not change and FE-SEM images showed that the surface was clearly maintained after tests.

Experimental validation of sound field control with a circular double-layer array of loudspeakers.

This paper is concerned with experimental validation of a recently proposed method of controlling sound fields with a circular double-layer array of loudspeakers [Chang and Jacobsen, J. Acoust. Soc. Am. 131(6), 4518-4525 (2012)]. The double-layer of loudspeakers is realized with 20 pairs of closed-box loudspeakers mounted back-to-back. Source strengths are obtained with several solution methods by modeling loudspeakers as a weighted combination of monopoles and dipoles. Sound pressure levels of the controlled sound fields are measured inside and outside the array in an anechoic room, and performance indices are calculated. The experimental results show that a method of combining pure contrast maximization with a pressure matching technique provides only a small error in the listening zone between the desired and the reproduced fields, and at the same time reduces the sound level in the quiet zone as expected in the simulation studies well above the spatial Nyquist frequency except at a few frequencies. It is also shown that errors in the positions of the loudspeakers can be critical to the results at frequencies where the distance between the inner and the outer array is close to half a wavelength.

Sound field control with a circular double-layer array of loudspeakers.

This paper describes a method of generating a controlled sound field for listeners inside a circular array of loudspeakers without disturbing people outside the array appreciably. To achieve this objective, a double-layer array of loudspeakers is used. Several solution methods are suggested, and their performance is examined using computer simulations. Two performance indices are used in this work, (a) the level difference between the average sound energy density in the listening zone and that in the quiet zone (sometimes called "the acoustic contrast"), and (b) a normalized measure of the deviations between the desired and the generated sound field in the listening zone. It is concluded that the best compromise is obtained with a method that combines pure contrast maximization with a pressure matching technique.

A plane wave generation method by wave number domain point focusing.

A method for generation of a wave-field that is a plane wave is described. This method uses an array of loudspeakers phased so that the field in the wave-number domain is nearly concentrated at a point, this point being at the wave-number vector of the desired plane wave. The method described here for such a wave-number concentration makes use of an expansion in spherical harmonics, and requires a relatively small number of measurement points for a good approximate achievement of a plane wave. The measurement points are on a spherical surface surrounding the array of loudspeakers. The input signals for the individual loudspeakers can be derived without a matrix inversion or without explicit assumptions about the loudspeakers. The mathematical development involves spherical harmonics and three-dimensional Fourier transforms. Some numerical examples are given, with various assumptions concerning the nature of the loudspeakers, that support the premise that the method described in the present paper may be useful in applications.

Optical resonant cavity in a nanotaper.

The present study describes an optical resonant cavity in a nanotaper with scale reduction from micro to several nanometers. Both experimental results and a finite-difference time-domain (FDTD)-based simulation suggested that the nanometer-scale taper with a diameter similar to the wavelength of light acted as a mirror, which facilitated the formation of a laser cavity and caused lasing in ZnO nanotapers. As the light inside the nanotaper propagated toward the apex, the lateral mode was reduced and reflection occurred. This report suggests that use of the resonant optical cavities in nanotapers might result in novel active and passive optical components, which will broaden the horizons of photonic technology.

Scattering effect on the sound focused personal audio system.

Recently, a personal audio system has been studied that uses an array of loudspeakers to localize sound to only the area around a user. To realize this system, beamforming or acoustic contrast control has been applied on the assumption that sources radiate sound in a free-field. This means that not only reflection by walls, but also the scattering effect by the user's head is neglected. Reflection by walls is negligible because personal devices are usually used in a short distance so that direct sound is dominant over reverberant sound. However, the scattering effect by the user's head has a considerable effect on the focused sound field. For example, the region where sound energy is not focused becomes louder when a user is actually in the focused region due to the scattered sound by the user's head in the focused region. In this paper, the scattering effect is shown computationally on the simple assumption that the user's head is a rigid sphere. Then, an improving control method, which overcomes this effect, is proposed. The method is shown to outperform the previous method in terms of lowering the sound level in the side regions when a user is in the bright zone.

A realization of sound focused personal audio system using acoustic contrast control.

A personal audio system that does not use earphone or any wire would have great interest and potential impact on the audio industries. In this study, a line array speaker system is used to localize sound in the listening zone. The contrast control [Choi, J.-W. and Kim, Y.-H. (2002). J. Acoust. Soc. Am. 111, 1695-1700] is applied, which is a method to make acoustically bright zone around the user and acoustically dark zone in other regions by maximizing the ratio of acoustic potential energy density between the bright and the dark zone. This ratio is regarded as acoustic contrast, analogous with what is used for optical devices. For the evaluation of the performance of acoustic contrast control, experiments are performed and the results are compared with those of uncontrolled case and time reversal array.

Regularized image reconstruction algorithms for positron emission tomography.

We develop algorithms for obtaining regularized estimates of emission means in positron emission tomography. The first algorithm iteratively minimizes a penalized maximum-likelihood (PML) objective function. It is based on standard de-coupled surrogate functions for the ML objective function and de-coupled surrogate functions for a certain class of penalty functions. As desired, the PML algorithm guarantees nonnegative estimates and monotonically decreases the PML objective function with increasing iterations. The second algorithm is based on an iteration dependent, de-coupled penalty function that introduces smoothing while preserving edges. For the purpose of making comparisons, the MLEM algorithm and a penalized weighted least-squares algorithm were implemented. In experiments using synthetic data and real phantom data, it was found that, for a fixed level of background noise, the contrast in the images produced by the proposed algorithms was the most accurate.