The uniform growth of single-crystal graphene over wafer-scale areas remains a challenge in the commercial-level manufacturability of various electronic, photonic, mechanical, and other devices based ...on graphene. Here, we describe wafer-scale growth of wrinkle-free single-crystal monolayer graphene on silicon wafer using a hydrogen-terminated germanium buffer layer. The anisotropic twofold symmetry of the germanium (110) surface allowed unidirectional alignment of multiple seeds, which were merged to uniform single-crystal graphene with predefined orientation. Furthermore, the weak interaction between graphene and underlying hydrogen-terminated germanium surface enabled the facile etch-free dry transfer of graphene and the recycling of the germanium substrate for continual graphene growth.
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BFBNIB, NMLJ, NUK, PNG, SAZU, UL, UM, UPUK
It is expected that artificial intelligence (AI) will be used extensively in the medical field in the future.
The purpose of this study is to investigate the awareness of AI among Korean doctors and ...to assess physicians' attitudes toward the medical application of AI.
We conducted an online survey composed of 11 closed-ended questions using Google Forms. The survey consisted of questions regarding the recognition of and attitudes toward AI, the development direction of AI in medicine, and the possible risks of using AI in the medical field.
A total of 669 participants completed the survey. Only 40 (5.9%) answered that they had good familiarity with AI. However, most participants considered AI useful in the medical field (558/669, 83.4% agreement). The advantage of using AI was seen as the ability to analyze vast amounts of high-quality, clinically relevant data in real time. Respondents agreed that the area of medicine in which AI would be most useful is disease diagnosis (558/669, 83.4% agreement). One possible problem cited by the participants was that AI would not be able to assist in unexpected situations owing to inadequate information (196/669, 29.3%). Less than half of the participants(294/669, 43.9%) agreed that AI is diagnostically superior to human doctors. Only 237 (35.4%) answered that they agreed that AI could replace them in their jobs.
This study suggests that Korean doctors and medical students have favorable attitudes toward AI in the medical field. The majority of physicians surveyed believed that AI will not replace their roles in the future.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
This study examined the effects of resistance training on muscle quality, muscle growth factors, and functional fitness in older adult women with sarcopenia. Twenty-two older adult women aged over 65 ...with sarcopenia were randomly assigned to either resistance training (RT, n = 12) or non-exercise control group (CG, n = 10). The body weight-based and elastic band RT were performed three times a week, 60 min per session, for 16 weeks. Body composition and thigh muscle quality were estimated by dual-energy X-ray absorptiometry (DEXA) and computed tomography (CT), respectively. The muscle growth factors, including growth differentiation factor-8 (GDF-8), growth differentiation factor-15 (GDF-15), activin A, and follistatin, were analyzed via blood samples. Statistical analyses were performed using repeated measures multivariate analysis of variance (MANOVA), analysis of variance (ANOVA), and effect size (i.e., cohen’s d, partial eta square), and the significance level was set at 0.05. The RT group improved their functional fitness, grip strength, gait speed, and isometric muscle strength (p < 0.01, d > 0.99; large), while these variables did not change in the CG. An increase in intramuscular fat was only observed in the CG (p < 0.01, 1.06; large). Muscle growth factors such as follistatin were significantly increased in the RT (p < 0.05, 0.81; large), but other variables did not change following resistance training. Sixteen weeks of resistance training improved functional fitness and prevented age-related increases in intramuscular fat in the thigh area. However, there were only some changes in muscle growth factors, such as follistatin, suggesting that the effectiveness of resistance training on muscle growth factors is limited. Body weight-based and elastic band resistance training is an alternative training method for sarcopenia to minimize the age-related adverse effects on muscle function and quality.
Recently, deep-learning-based approaches have been proposed for the classification of neuroimaging data related to Alzheimer's disease (AD), and significant progress has been made. However, ...end-to-end learning that is capable of maximizing the impact of deep learning has yet to receive much attention due to the endemic challenge of neuroimaging caused by the scarcity of data. Thus, this study presents an approach meant to encourage the end-to-end learning of a volumetric convolutional neural network (CNN) model for four binary classification tasks (AD vs. normal control (NC), progressive mild cognitive impairment (pMCI) vs. NC, stable mild cognitive impairment (sMCI) vs. NC and pMCI vs. sMCI) based on magnetic resonance imaging (MRI) and visualizes its outcomes in terms of the decision of the CNNs without any human intervention. In the proposed approach, we use convolutional autoencoder (CAE)-based unsupervised learning for the AD vs. NC classification task, and supervised transfer learning is applied to solve the pMCI vs. sMCI classification task. To detect the most important biomarkers related to AD and pMCI, a gradient-based visualization method that approximates the spatial influence of the CNN model's decision was applied. To validate the contributions of this study, we conducted experiments on the ADNI database, and the results demonstrated that the proposed approach achieved the accuracies of 86.60% and 73.95% for the AD and pMCI classification tasks respectively, outperforming other network models. In the visualization results, the temporal and parietal lobes were identified as key regions for classification.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Sarcopenia, an age-related disease, is one of the important health problems in the elderly and the prevalence of sarcopenia is rapidly increased among the Korean population. This study examined the ...muscle quality and muscle growth factors of elderly women to identify the potential diagnostic tool for sarcopenia. One hundred and thirty-six elderly women, aged over 65 years old, initially enrolled, but only 59 participants who met the criteria (sarcopenic group, n = 27; non-sarcopenic group, n = 32) completed the study. Muscle quality assessment included thigh cross-sectional computed tomography scan and maximal isometric muscle strength. Muscle growth factors such as GDF-15, myostatin, activin A, and follistatin were analyzed, and a battery of Senior Fitness Test was used to examine functional fitness. The statistical significance level was set at 0.05. Elderly women with sarcopenia had a lower thigh muscle volume (−20.1%), and a higher thigh intermuscular adipose tissue (15.8%) than those of the non-sarcopenic group (p < 0.05). However, no significant differences in muscle growth factors were observed between the groups. Muscle quality variables including maximal voluntary isometric contraction (OR: 0.968, p < 0.001), relative maximal voluntary isometric contraction (OR: 0.989, p < 0.05), thigh muscle volume (OR: 0.836, p < 0.001), and thigh intermuscular adipose tissue (OR: 1.138, p < 0.05) were associated with a risk of sarcopenia. Our findings suggest that the sarcopenic group exhibits a poor thigh muscle quality in comparison with the non-sarcopenic group. Muscle quality assessment can be utilized for sarcopenia identification, but our study remains inconclusive for the causality of muscle growth factors in sarcopenia.
Background
The effect of diet on allergic rhinitis (AR), its severity in children, and whether it modifies AR depending on genetic susceptibility are unknown. We investigated the association between ...dietary patterns and AR in school children and the influence of diet on AR according to a genetic risk score (GRS).
Methods
Totally, 435 7‐year‐old school children were recruited from the Panel Study on Korean Children. We used dietary patterns (vegetable, sugar, and meat) and dietary inflammatory index (DII) as dietary parameters. AR and its severity were defined by questionnaires about treatment in the previous 12 months and the Allergic Rhinitis and its Impact on Asthma (ARIA) guideline, respectively. A GRS was calculated using 6 single nucleotide polymorphisms for allergic diseases.
Results
A vegetable diet containing a lot of anti‐inflammatory nutrients and higher vitamin D level in blood were negatively correlated, while DII was positively correlated with triglyceride level and triglyceride/HDL cholesterol. Vegetable diet (aOR, 95% CI = 0.73, 0.58‐0.94) and DII (1.13, 1.01‐1.28) were associated with AR risk. In particular, a high‐vegetable diet resulted in a lower risk of mild and persistent AR (aOR, 95% CI = 0.24, 0.10‐0.56) while a high DII represented a higher risk (2.33, 1.06‐5.10). The protective effect of vegetable diet on AR appeared only among children with a lower GRS (adjusted P = .018).
Conclusions
A vegetable dietary pattern characterized by high intake of anti‐inflammatory nutrients and higher vitamin D level in blood might be associated with a lower risk of mild and persistent AR. This beneficial effect is modified by a genetic factor.
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BFBNIB, DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
Mass appraisal is the standardized procedure of valuing a large number of properties at the same time and is commonly used to compute real estate tax. While a hedonic pricing model based on the ...ordinary least squares (OLS) linear regression has been employed as the traditional method in this process, the stability and accuracy of the model remain questionable. This paper investigates the features of a house price predictor based on the Random Forest (RF) method by comparing it with that of a conventional hedonic pricing model. We used apartment transaction data from the period of 2006 to 2017 in the district of Gangnam, one of the most developed areas in South Korea. Using a data set covering 40% of all transactions in the sample area, we demonstrate that the accuracy of a machine learning-based predictor can be surprisingly high. The average of percentage deviations between the predicted and the actual market price was found to be only around 5.5% in the RF predictor, whereas it was almost 20% in the OLS-based predictor. With the RF predictor, the probability of the predicted price being within 5% of its actual market price was 72%, while only about 17.5% of the regression-based predictions fell within the same range. These results show that, in the practice of mass appraisal, the RF method may be a useful complement to the hedonic models, as it more adequately captures the complexity or non-linearity of actual housing markets.
Smart fabrics and interactive textiles have attracted great interest as a newly emergent material because of their multifunctional capabilities. Herein, a highly robust wireless flexible strain ...sensor on the basis of commercial textile by the integration of functional hybrid carbon nanomaterials and piezoresistive material is fabricated. Specifically, a solution‐processable spray‐assisted coating approach that enables the creation of a uniform coating over a large area of fabrics is employed. The textile‐based strain sensor exhibits a highly stable and immediate response over a wide range of bending curvatures and structural properties of ZnO nanowires because of their different deflection behaviors. The wearing performance with attaching on commercial fabrics is further demonstrated. The as‐prepared sensor responds well to diverse body motions with accurate detection of strain magnitude and even extends its viability in wireless remote sensing by connecting to a wireless transmitter. The novel approach for the modification of textiles with functional nanomaterials may provide a feasible approach for the production of textile‐based electronics without employing any sophisticated fabrication processes, and it further exploits the diverse functionalities by utilizing various sensing components.
A highly robust flexible strain sensor is fabricated through a facile integration of functional nanomaterials into a textile platform. It well demonstrates not only a rapid response to diverse body motions but also different strain sensing behaviors depending on geometrical features of ZnO nanostructure. Furthermore, the capability of the textile‐based sensor is extended to remote monitoring by configuration with wireless transmitter.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Spatial light modulators are essential optical elements in applications that require the ability to regulate the amplitude, phase and polarization of light, such as digital holography, optical ...communications and biomedical imaging. With the push towards miniaturization of optical components, static metasurfaces are used as competent alternatives. These evolved to active metasurfaces in which light-wavefront manipulation can be done in a time-dependent fashion. The active metasurfaces reported so far, however, still show incomplete phase modulation (below 360°). Here we present an all-solid-state, electrically tunable and reflective metasurface array that can generate a specific phase or a continuous sweep between 0 and 360° at an estimated rate of 5.4 MHz while independently adjusting the amplitude. The metasurface features 550 individually addressable nanoresonators in a 250 × 250 μm
area with no micromechanical elements or liquid crystals. A key feature of our design is the presence of two independent control parameters (top and bottom gate voltages) in each nanoresonator, which are used to adjust the real and imaginary parts of the reflection coefficient independently. To demonstrate this array's use in light detection and ranging, we performed a three-dimensional depth scan of an emulated street scene that consisted of a model car and a human figure up to a distance of 4.7 m.
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GEOZS, IJS, IMTLJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK, ZAGLJ
Sensitive and deformable chemical sensors manufactured by a low-cost process are promising as they are disposable, can be applied on curved, complex structures, and provide environmental information ...to users. Although many nanomaterial-based flexible sensors have been suggested to meet these demands, their limited chemical sensitivity and mechanical flexibility pose challenges. Here, a highly deformable chemical sensor is reported with improved sensitivity that integrates multiwalled carbon nanotubes (CNTs) and nanolayered transition metal dichalcogenides (TMDCs) on cellulose paper. Liquid dispersions of CNTs and TMDCs are absorbed and dried on porous cellulose for sensor fabrication, which is simple, scalable, rapid, and inexpensive. The cellulose substrate enables reversible three-dimensional folding and unfolding, bending down to 0.25 mm, and twisting up to 1800° (∼628.4 rad m–1) without degradation, and the CNTs maintain a percolation network and simultaneously provide gas reactivity. Functionalization of CNTs with TMDCs (WS2 or MoS2) greatly improves the sensing response upon exposure to NO2 molecules by more than 150%, and the sensor can also selectively detect NO2 over diverse reducing vapors. The measured NO2 sensitivity is 4.57% ppm–1, which is much higher than that of previous paper-based sensors. Our sensor can stably and sensitively detect the gas even under severe deformation such as heavy folding and crumpling. Hybrid integration of CNTs and TMDCs on cellulose paper may also be used to detect other harmful gases and can be applicable in low-cost portable devices that require reliable deformability.
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IJS, KILJ, NUK, PNG, UL, UM