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Autonomous unmanned aerial vehicles (UAVs) require highly reliable navigation information. Generally, navigation systems with the inertial navigation system (INS) and global navigation satellite system (GNSS) have been widely used. However, the GNSS is vulnerable to jamming and spoofing. The terrain referenced navigation (TRN) technique can be used to solve this problem. In this study, to obtain reliable navigation information even if a GNSS is not available or the degree of terrain roughness is not determined, we propose a federated filter based INS/GNSS/TRN integrated navigation system. we also introduce a TRN system that combines batch processing and an auxiliary particle filter to ensure stable flight of UAVs even in a long-term GNSS-denied environment. As an altimeter sensor for the TRN system, we use an interferometric radar altimeter (IRA) to obtain reliable navigation accuracy in high altitude flight. In addition, a parallel computing technique with general-purpose computing on graphics processing units (GPGPU) is applied to process a high resolution terrain database and a nonlinear filter in real time on board. Finally, we verify the performance of the proposed system through software-in-the-loop (SIL) tests and captive flight tests in a GNSS unavailable environment.

BACKGROUND: Three-dimensional (3D) cell cultures with architectural and biomechanical properties similar to those of natural tissue have been the focus for generating liver tissue. Microarchitectural organization is believed to be crucial to hepatic function, and 3D cell culture technologies have enabled the construction of tissue-like microenvironments, thereby leading to remarkable progress in vitro models of human tissue and organs. Recently, to recapitulate the 3D architecture of tissues, spheroids and organoids have become widely accepted as new practical tools for 3D organ modeling. Moreover, the combination of bioengineering approach offers the promise to more accurately model the tissue microenvironment of human organs. Indeed, the employment of sophisticated bioengineered liver models show long-term viability and functional enhancements in biochemical parameters and disease-orient outcome. RESULTS: Various 3D in vitro liver models have been proposed as a new generation of liver medicine. Likewise, new biomedical engineering approaches and platforms are available to more accurately replicate the in vivo 3D microarchitectures and functions of living organs. This review aims to highlight the recent 3D in vitro liver model systems, including micropatterning, spheroids, and organoids that are either scaffold-based or scaffold-free systems. Finally, we discuss a number of challenges that will need to be addressed moving forward in the field of liver tissue engineering for biomedical applications. CONCLUSION: The ongoing development of biomedical engineering holds great promise for generating a 3D biomimetic liver model that recapitulates the physiological and pathological properties of the liver and has biomedical applications.

Multiple Myeloma (MM) is a hematological malignancy of plasma cells. Although advanced therapies have elevated MM survival rate, MM eventually relapses. Relapsed/refractory MM (R/R MM) cells gain resistance to previously used drugs, which reduces treatment options. In this study, we propose a newly synthesized HDAC6-selective inhibitor, A452, as a strategy to overcome resistance to immunomodulatory drugs (IMiDs), the principal MM therapeutic drugs. Here, we identified that A452 alone reduces the viability and growth of IMiDs-resistant cells as well as synergistically reduces viability when combined with IMiDs. We confirmed that this anticancer activity occurrs by inducing apoptosis. To determine if A452 overcomes IMiDs resistance, we checked the change in the protein level of IMiDs direct/indirect targets. As a result, the combination of A452 and IMiDs slightly increased CRBN and decreased Aiolos and Ikaros, the targets of CRBN. Moreover, A452 decreased c-Myc and IRF-4 when combined with IMiDs. These data suggest that A452 helps to overcome the resistance of IMiDs. Finally, significant synergy of anticancer activity was detected when using triple combinations of A452, IMiDs, and dexamethasone. In conclusion, the novel HDAC6-selective inhibitor A452 would be beneficial to combination therapy, including IMiDs in R/R MM as a strategy for overcoming IMiDs resistance.

Nanomaterials with antioxidant properties are promising for treating reactive oxygen species (ROS)-related diseases. However, maintaining efficacy at low doses to minimize toxicity is a critical for clinical applications. Tuning the surface strain of metallic nanoparticles can enhance catalytic reactivity, which has rarely been demonstrated in metal oxide nanomaterials. Here, it is shown that inducing surface strains of CeO

The extent of anthropogenic land use in watersheds determines the amount of pollutants discharged to streams. This indirectly and directly affects stream water quality and biological health. Most studies have therefore focused on ways to reduce non-point pollution sources to streams from the surrounding land use in watersheds. However, the mechanistic pathways between land use and the deterioration of stream water quality and biological assemblages remain unclear. This study estimated a structural equation model (SEM) representing the impact of agricultural and urban land use on water quality and the benthic macroinvertebrate index (BMI) using IBM AMOS in the Nam-Han river systems, South Korea. The estimated SEM showed that the percent of urban and agricultural land in the watersheds significantly affected both the water quality and the BMI of the streams. Specifically, a higher percent of urban land use had directly increased the biochemical oxygen demand (BOD) and total phosphorus (TP), and deteriorated the BMI of streams. Similarly, higher proportions of agricultural land use had also directly increased the BOD, total nitrogen (TN), and total phosphorus (TP) concentrations, and lowered the BMI of streams. In addition, it was observed that the percent of urban and agricultural land use had indirectly deteriorated the BMI through increased BOD. However, we were not able to observe any significant indirect effect of the percent of urban and agricultural land use through increased nutrients including TN and TP. These results indicate that increased urban and agricultural land use in the watersheds had directly and indirectly affected the physicochemical characteristics and benthic macroinvertebrate communities in streams. Our findings emphasize the need to develop more elaborate environmental management and restoration strategies to improve the water quality and biological status of streams.

Understanding the complex relationships between land use and stream water quality is critical for water pollution control and watershed management. This study aimed to investigate the relationship between land use types and water quality indicators at multiple spatial scales, namely, the watershed and riparian scales, using the ordinary least squares (OLS) and geographically weighted regression (GWR) models. GWR extended traditional regression models, such as OLS to address the spatial variations among variables. Our results indicated that the water quality indicators were significantly affected by agricultural and forested areas at both scales. We found that extensive agricultural land use had negative effects on water quality indicators, whereas, forested areas had positive effects on these indicators. The results also indicated that the watershed scale is effective for management and regulation of watershed land use, as the predictive power of the models is much greater at the watershed scale. The maps of estimated local parameters and local R2 in GWR models showcased the spatially varying relationships and indicated that the effects of land use on water quality varied over space. The results of this study reinforced the importance of watershed management in the planning, restoration, and management of stream water quality. It is also suggested that planners and managers may need to adopt different strategies, considering watershed characteristics&mdash, such as topographic features and meteorological conditions&mdash, and the source of pollutants, in managing stream water quality.

With the development in wireless communication and low-power device, users can receive various useful services such as electric vehicle (EV) charging, smart building, and smart home services at anytime and anywhere in smart grid (SG) environments. The SG devices send demand of electricity to the remote control center and utility center (UC) to use energy services, and UCs handle it for distributing electricity efficiently. However, in SG environments, the transmitted messages are vulnerable to various attacks because information related to electricity is transmitted over an insecure channel. Thus, secure authentication and key agreement are essential to provide secure energy services for legitimate users. In 2019, Kumar et al. presented a secure authentication protocol for demand response management in the SG system. However, we demonstrate that their protocol is insecure against masquerade, the SG device stolen, and session key disclosure attacks and does not ensure secure mutual authentication. Thus, we propose a privacy-preserving lightweight authentication protocol for demand response management in the SG environments to address the security shortcomings of Kumar et al.&rsquo, s protocol. The proposed protocol withstands various attacks and ensures secure mutual authentication and anonymity. We also evaluated the security features of the proposed scheme using informal security analysis and proved the session key security of proposed scheme using the ROR model. Furthermore, we showed that the proposed protocol achieves secure mutual authentication between the SG devices and the UC using Burrows&ndash, Abadi&ndash, Needham (BAN) logic analysis. We also demonstrated that our authentication protocol prevents man-in-the-middle and replay attacks utilizing AVISPA simulation tool and compared the performance analysis with other existing protocols. Therefore, the proposed scheme provides superior safety and efficiency other than existing related protocols and can be suitable for practical SG environments.

This study aimed to develop a prognosis-predicting model based on [18F]fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) and clinicopathologic factors in locally advanced cervical cancer patients treated with concurrent chemoradiotherapy (CCRT). The medical records of 270 locally advanced cervical cancer patients who were treated with CCRT were collected from three institutions and reviewed retrospectively. A nomogram was used for predicting 2-year disease-free survival (DFS) and 5-year overall survival (OS) based on Cox proportional hazards regression. Predictor variables included nodal maximum standardized uptake value (SUVmax), primary tumor SUVmax, age, tumor size, stage, serum squamous cell carcinoma antigen level, and human papillomavirus status. Internal nomogram validation was performed. A nomogram for predicting the 2-year DFS and 5-year OS was constructed using six and seven parameters, respectively. With a focus on 2-year DFS, our model found nodal SUVmax to be the highest weighted negative prognostic factor. With a focus on 5-year OS, young age was the highest weighted negative prognostic factor. The concordance index was 0.75 and 0.78 for the 2-year DFS and 5-year OS, respectively. This nomogram is a predictive tool that can be used to counsel patients for predicting survival outcomes. Moreover, our prognosis-predicting model may make it possible to personalize treatment.

Naver V Live, a South Korean live-streaming service, showcases video contents specific to the entertainment industry, such as K-pop and music. On V Live, K-pop stars and their fans can interact directly in a natural way, and V Live provides high-quality video content with novel topics. This study has identified key characteristics of video content that affect its popularity. A total of 620 video contents of five leading Star channels were classified on the basis of production company, type of video content, and whether it was live-streamed or not. The popularity of video content was measured by the number of comments, hearts, and views. To control potential bias, additional variables were set as control variables&mdash, such as the number of channel subscribers, mini-album sales, if the video content was previewed, and cumulative number of days since the video content was uploaded. For analysis, a hierarchical linear regression was conducted. The findings suggest future directions in video content planning.

Wikstroemia indica (L.) C.A. Mey. is used in traditional Chinese medicine to treat inflammatory diseases such as arthritis and bronchitis. In this study, we aimed to investigate the effects of an ethanolic extract of W. indica on cutaneous inflammation in mice with 2,4-dinitrochlorobenzene (DNCB)-induced atopic dermatitis (AD). Dermal administration of W. indica ethanolic extract to DNCB-sensitized hairless mice with dermatitis, for two weeks, reduced erythema, scaling, and edema. Skin hydration was improved and transepidermal water loss was reduced at a W. indica concentration of 1%. Furthermore, W. indica also significantly reduced serum IgE and IL-4 concentrations in our mouse model. These results suggest that W. indica has potential as a topical treatment for AD and as an adjunctive agent to control AD.

Additional file 1.

Language model pre-training has shown promising results in various downstream tasks. In this context, we introduce a cross-modal pre-trained language model, called Speech-Text BERT (ST-BERT), to tackle end-to-end spoken language understanding (E2E SLU) tasks. Taking phoneme posterior and subword-level text as an input, ST-BERT learns a contextualized cross-modal alignment via our two proposed pre-training tasks: Cross-modal Masked Language Modeling (CM-MLM) and Cross-modal Conditioned Language Modeling (CM-CLM). Experimental results on three benchmarks present that our approach is effective for various SLU datasets and shows a surprisingly marginal performance degradation even when 1% of the training data are available. Also, our method shows further SLU performance gain via domain-adaptive pre-training with domain-specific speech-text pair data., Comment: ICASSP 2021; 5 pages

Recent works in dialogue state tracking (DST) focus on an open vocabulary-based setting to resolve scalability and generalization issues of the predefined ontology-based approaches. However, they are inefficient in that they predict the dialogue state at every turn from scratch. Here, we consider dialogue state as an explicit fixed-sized memory and propose a selectively overwriting mechanism for more efficient DST. This mechanism consists of two steps: (1) predicting state operation on each of the memory slots, and (2) overwriting the memory with new values, of which only a few are generated according to the predicted state operations. Our method decomposes DST into two sub-tasks and guides the decoder to focus only on one of the tasks, thus reducing the burden of the decoder. This enhances the effectiveness of training and DST performance. Our SOM-DST (Selectively Overwriting Memory for Dialogue State Tracking) model achieves state-of-the-art joint goal accuracy with 51.72% in MultiWOZ 2.0 and 53.01% in MultiWOZ 2.1 in an open vocabulary-based DST setting. In addition, we analyze the accuracy gaps between the current and the ground truth-given situations and suggest that it is a promising direction to improve state operation prediction to boost the DST performance., Accepted to ACL2020 as a long paper

As a new class of cancer therapeutic agents, oncolytic viruses (OVs) have gained much attention not only due to their ability to selectively replicate in and lyse tumor cells, but also for their potential to stimulate antitumor immune responses. As a result, there is an increasing need for in vitro modeling systems capable of recapitulating the 3D physiological tumor microenvironment. Here, we investigated the potential of our recently developed microphysiological system (MPS), featuring a vessel-like channel to reflect the in vivo tumor microenvironment and serving as culture spaces for 3D multicellular tumor spheroids (MCTSs). The MCTSs consist of cancer A549 cells, stromal MRC5 cells, endothelial HUVECs, as well as the extracellular matrix. 3D MCTSs residing in the MPS were infected with oncolytic VSV expressing GFP (oVSV-GFP). Post-infection, GFP signal intensity increased only in A549 cells of the MPS. On the other hand, HUVECs were susceptible to virus infection under 2D culture and IFN-β secretion was quite delayed in HUVECs. These results thus demonstrate that OV antitumoral characteristics can be readily monitored in the MPS and that its behavior therein somewhat differs compared to its activity in 2D system. In conclusion, we present the first application of the MPS, an in vitro model that was developed to better reflect in vivo conditions. Its various advantages suggest the 3D MCTS-integrated MPS can serve as a first line monitoring system to validate oncolytic virus efficacy.

Automatic speech recognition (ASR) via call is essential for various applications, including AI for contact center (AICC) services. Despite the advancement of ASR, however, most publicly available call-based speech corpora such as Switchboard are old-fashioned. Also, most existing call corpora are in English and mainly focus on open domain dialog or general scenarios such as audiobooks. Here we introduce a new large-scale Korean call-based speech corpus under a goal-oriented dialog scenario from more than 11,000 people, i.e., ClovaCall corpus. ClovaCall includes approximately 60,000 pairs of a short sentence and its corresponding spoken utterance in a restaurant reservation domain. We validate the effectiveness of our dataset with intensive experiments using two standard ASR models. Furthermore, we release our ClovaCall dataset and baseline source codes to be available via https://github.com/ClovaAI/ClovaCall., Comment: 5 pages, 2 figures, 4 tables, The first two authors equally contributed to this work

Green roofs are implemented to reduce the urban heat island effect; however, studies are limited to comparing the reduction in urban heat island effect before and after implementation, and the focus is on the structural stability of the building rather than urban heat island reduction. In this study, using the sky view factor (SVF) in ENVI-met, a 3D microclimate modeling program, urban spaces were classified as closed, semi-open, and open areas. Meanwhile, the green roof types were subdivided according to the vegetation coverage rates, which included grass, shrubs, and trees. The vegetation ratio was evaluated using ENVI-met to determine which of the 10 scenarios was most effective for each urban space. The thermal environment was most comfortable in semi-open areas. Therefore, the green roof scenario with 70% grass and 30% trees was effective in closed areas, 50% shrubs and 50% trees were best in semi-open areas, and 70% grass with 30% trees, or 30% grass and 70% trees, was best in open areas. This study provides a basis for creating green roof guidelines aimed at improving the urban thermal environment, as well as creating other green infrastructure elements in cities.

Objective The purpose of the current study was to investigate the diagnostic performance of high mobility group A2 (HMGA2) gene expression for differentiation of malignant thyroid nodules through a systematic review and meta-analysis. Design The MEDLINE/PubMed and EMBASE database, from the earliest available date of indexing through 10 April 2018, were searched for studies evaluating the diagnostic performance of HMGA2 expression for differentiation of thyroid nodules. Methods We determined the sensitivities and specificities across studies, calculated positive and negative likelihood ratios (LR+ and LR-), and constructed summary receiver operating characteristic (ROC) curves. Results Across 7 studies, the pooled sensitivity for HMGA2 expression was 0.78 (95% CI; 0.67-0.86) with heterogeneity (I2 = 86.6) and a pooled specificity of 0.94 (95% CI: 0.85-0.98) with heterogeneity (I2 = 94.7). Likelihood ratio (LR) syntheses gave an overall positive likelihood ratio (LR+) of 12.6 (95% CI: 5.1-31.3) and negative likelihood ratio (LR-) of 0.24 (95% CI: 0.15-0.36). The pooled diagnostic odds ratio (DOR) was 53 (95% CI: 18-159). Hierarchical summary ROC curve indicates that the areas under the curve were 0.92 (95% CI: 0.89-0.94). In meta-regression analysis, no definite variable was the source of the study heterogeneity. Conclusion The current meta-analysis showed the moderate sensitivity and high specificity of HMGA2 expression for differentiation of malignant thyroid nodules. The likelihood ratio scatter-gram suggested that HMGA2 expression analysis could be useful for confirmation of the presence of malignant thyroid nodules. Considering the heterogeneity of included studies, further large prospective studies are necessary to confirm these results.

Background/Aims: Ulcerative colitis undergoes periods of exacerbation and remission. Fecal calprotectin levels increase with gut inflammation and correlate with endoscopic disease activity in ulcerative colitis. Intestinal blood loss and fecal im munochemical test levels also correlate with endoscopic disease activity. This study statistically evaluated the usefulness of fecal calprotectin, fecal immunochemical test, and C-reactive protein (CRP) as markers of disease activity. Methods: A total 106 ulcerative colitis patients who underwent endoscopy and fecal calprotectin, fecal immunochemical test, and CRP testing, from March 2015 to August 2016, were retrospectively reviewed. Disease activity was assessed using a partial Mayo score and Mayo endoscopic score. The ability of fecal and serologic tests to reflect endoscopic disease severity was statistically evaluated. Results: Among 106 patients, 68 underwent endoscopy and stool study within 2 weeks. In patients with mild to severe activity, fecal immunochemical test and fecal calprotectin were superior to CRP at Mayo endoscopic score detection rate. The area un der the curves of fecal immunochemical test and fecal calprotectin for the detection of Mayo endoscopic score ≥1 were 0.956 and 0.942, respectively, and were superior to that of CRP (0.756). At Mayo endoscopic score, the effects of combination of fecal immunochemical test and CRP or fecal calprotectin and CRP were found to be higher than those of the independent fecal im munochemical test or fecal calprotectin. Conclusions: Fecal immunochemical test and fecal calprotectin can effectively detect active ulcerative colitis better than remission. As these markers reflect the status of mucosal inflammation, they may reduce the requirement for invasive endoscopic examination. (Intest Res 2018;16:563-570)

Background We investigated the inhibitory effect of pantoprazole on signal transducer and activator of transcription 3 (STAT3) activity and invasiveness of gastric adenocarcinoma cells, and the role of SH2-containing protein tyrosine phosphatase 1 (SHP-1) in mediating role. Methods We used AGS and MKN-28 cells because of reduced SHP-1 and preserved p-STAT3 expression. Western blot, wound closure assay, Matrigel invasion assay and 3-D culture invasion assay were performed. Pharmacologic inhibitor of SHP-1 and siRNA were used for validation of the role of SHP-1. Results We observed that pantoprazole at 40, 80, and 160 μg/ml upregulated SHP-1 and downregulated p-STAT3 expression in a dose-dependent manner in AGS and MKN-28 cells. Furthermore, pantoprazole significantly downregulated mesenchymal markers (Snail1 and vimentin), upregulated epithelial marker (E-cadherin), and inhibited migration and invasion of AGS and MKN-28 cells. To validate the role of SHP-1 in inhibition of STAT3 activity by pantoprazole in gastric cancer cells, we performed pharmacologic inhibition (pervanadate) or knockdown of SHP-1 before pantoprazole treatment, which significantly attenuated the suppression of p-STAT3 and anti-migration and invasion effect by pantoprazole in AGS cells. In xenograft tumor model, tumor volume was significantly reduced by intraperitoneal injection of pantoprazole, with upregulation of SHP-1 and downregulation of p-STAT3, which were attenuated by concomitant injection of pervanadate. Conclusion Our data suggest that the inhibitory effect of pantoprazole on cellular migration and invasion might be through inducing SHP-1 in gastric cancer cells.

Anoctamin1 (ANO1), a calcium activated chloride channel, is known to play a critical role in salivary secretion. In the salivary gland, ANO1 is expressed exclusively in the acinar cells, with no expression in the ductal cells. However, the mechanisms that determine this distinctive cell type-dependent expression pattern of ANO1 remain unknown. In this study, we discovered that the cell-dependent expression of ANO1 during salivary gland organogenesis is regulated by DNA methylation of ANO1 CpG islands. ANO1 CpG islands in e12 embryonic submandibular glands (eSMG) are highly methylated, but those in e14 eSMG or adult SMG are significantly unmethylated. The differential expression pattern of ANO1 in duct and acini is defined at e14. Artificial demethylation by treatment with the demethylating agent 5-aza-2&rsquo, deoxycytidine (5-Aza-CdR), induced the expression of ANO1 in both the ductal cell line Human Submandibular Gland (HSG) and in the duct cells of adult mouse SMG. During the trans-differentiation in Matrigel of duct-origin HSG cells into acinar-like phenotype, significant demethylation of ANO1 CpG islands is observed. This may be due to the reduced expression of DNA methyltransferase (DNMT) 3a and 3b. These results suggest that the differential expression of ANO1 in salivary glands during organogenesis and differentiation is mainly regulated by epigenetic demethylation of the ANO1 gene.

This paper empirically presents the impact of the correlation-based feature selection on the accuracy of the photovoltaic (PV) power prediction, and then selects the weather variables that maximize prediction accuracy. To this end, the experiments are conducted using the weather dataset consisting of eighteen weather variables (i.e., features). For experiments, we first calculate a correlation coefficient of each weather variable by analyzing the correlation between PV power and each weather variable. Then, we create the subsets of weather variables considering the absolute value of correlation coefficient and generate the multiple prediction models using the created subsets. Finally, the accuracy of the generated prediction models is compared with each other to find the most accurate prediction model. The experiment results provide a reference guideline for selecting the weather variables that maximize the accuracy of PV power prediction.

국내 뉴스 이용자는 대부분 네이버나 다음 등 포털사이트를 통해 뉴스를 소비한다. 뉴스 이용자가 포털사이트를 통해 뉴스를 소비하는 가장 주요한 이유는 하나의 웹사이트에서 다양한 뉴스 콘텐츠를 편리하게 접할 수 있기 때문이다. 포털사이트에 뉴스를 공급하는 언론사는 뉴스 이용자의 트래픽에 따라 수익을 얻는다. 자사의 뉴스에 이용자가 많이 유입될수록 더 많은 수익을 얻을 수 있는 구조이다. 따라서 뉴스 공급자는 뉴스 이용자에게 자사의 뉴스가 가능한 많이 노출될 수 있도록 여러 가지 방법을 고안한다. 최근에는 포털사이트 이용자가 실시간 검색어를 클릭하거나 관련 뉴스를 검색할 때 해당 기사가 웹페이지 상단에 떠오르도록 비슷한 기사를 반복적으로 송고하는 행위인 ‘뉴스 어뷰징’이 포털 뉴스의 문제점으로 제기되고 있다. 뉴스 어뷰징은 특정 키워드와 관련된 동일하거나 비슷한 뉴스가 과도하게 양산되어 사회적 여론이 편향되거나 뉴스 이용자가 다양한 뉴스를 선택할 권리를 훼손할 수 있다는 위험성이 있다. 이러한 위험성에도 불구하고 아직 뉴스어뷰징에 대한 정의, 뉴스 어뷰징 여부 판단 기준 등에 대한 연구는 부족하다. 본 연구는 현재 포털사이트에서 뉴스 어뷰징 현상이 어떻게 나타나는지 파악하고, 어뷰징 정도를 정량적으로 측정하기 위한 방안을 제시하였다. 이를 위해 국내 포털 사업자 중 가장 높은 점유율을 차지하고 있는 네이버에서 2017년 10월에 발생한 ‘슈퍼주니어 최시원의 프렌치불독으로부터 개물림 사고를 당한 한일관 대표가 사망한 사건’에 대한 기사를 수집하고, 분석대상 기사 총 641개에 대한 내용분석을 통해 어뷰징 정도를 정량적으로 산출하였다. 본 연구는 포털사이트에서 발생하는 뉴스 어뷰징 정도를 정량적으로 측정하기 위한 방법을 제안하였다는 점에서 학술적 시사점이 있다. 또한, 뉴스 어뷰징 실태를 수치로 제시했다는 점에서 향후 보다 신뢰할 수 있는 온라인 뉴스 환경을 조성하는데 기여할 것이라 기대한다.

Wearable and implantable devices require conductive, stretchable and biocompatible materials. However, obtaining composites that simultaneously fulfil these requirements is challenging due to a trade-off between conductivity and stretchability. Here, we report on Ag–Au nanocomposites composed of ultralong gold-coated silver nanowires in an elastomeric block-copolymer matrix. Owing to the high aspect ratio and percolation network of the Ag–Au nanowires, the nanocomposites exhibit an optimized conductivity of 41,850 S cm−1 (maximum of 72,600 S cm−1). Phase separation in the Ag–Au nanocomposite during the solvent-drying process generates a microstructure that yields an optimized stretchability of 266% (maximum of 840%). The thick gold sheath deposited on the silver nanowire surface prevents oxidation and silver ion leaching, making the composite biocompatible and highly conductive. Using the nanocomposite, we successfully fabricate wearable and implantable soft bioelectronic devices that can be conformally integrated with human skin and swine heart for continuous electrophysiological recording, and electrical and thermal stimulation. A highly conductive, biocompatible and stretchable nanocomposite based on ultralong gold-coated silver nanowires allows for the realization of wearable and implantable bioelectronics.

Exosomes are endogenous nanocarriers that can deliver biological information between cells. They are secreted by all cell types, including immune cells such as natural killer (NK) cells. However, mammalian cells release low quantities of exosomes, and the purification of exosomes is difficult. Here, nanovesicles were developed by extrusion of NK cells through filters with progressively smaller pore sizes to obtain exosome mimetics (NK-EM). The anti-tumour effect of the NK-EM was confirmed in vitro and in vivo. The morphological features of the NK-EM were revealed by transmission electron microscopy (TEM), nanoparticle tracking analysis (NTA) and Western blot. In vitro, the cytotoxicity of the NK-EM to cancer cells (glioblastoma, breast carcinoma, anaplastic thyroid cancer and hepatic carcinoma) was assessed using bioluminescence imaging (BLI) and CCK-8 assay. For in vivo study, a xenograft glioblastoma mouse model was established. The anti-tumour activity of NK-EM was confirmed in vivo by the significant decreases of BLI, size and weight (all p .001) of the tumour compared with the control group. Moreover, NK-EM cytotoxicity for glioblastoma cells that related with decreased levels of the cell survival markers p-ERK and p-AKT, and increased levels of apoptosis protein markers cleaved-caspase 3, cytochrome-c and cleaved-PARP was confirmed. All those results suggest that NK-EM exert stronger killing effects to cancer cells compared with the traditional NK-Exo, at the same time, the tumour targeting ability of the NK-EM was obtained in vivo. Therefore, NK-EM might be a promising immunotherapeutic agent for treatment of cancer.

As office workers’ use of social networking sites (SNSs) has increased, so has research interest in the effect of SNS use on job performance. The present study employs data collected from South Kor...

This study aimed to examine whether the characteristics of mental health and sleep duration, alone or in combination, are associated with menstrual cycle irregularity. This population-based, cross-sectional study analyzed the data from 4445 women aged 19-49 years, who participated in the Korea National Health and Nutrition Examination Survey 2010-2012. A structured questionnaire was used to assess mental health characteristics, sleep duration, and menstrual cycle irregularity. A multivariable logistic regression analysis was performed. High stress, depressive mood, and suicidal ideation were associated with increased risk of menstrual cycle irregularity after adjusting for confounding variables (odds ratio [95% confidence interval] = 1.33 [1.07-1.65], 1.56 [1.17-2.07], and 1.37 [1.01-1.87], respectively). Short sleep duration (≤ 5 h a day) was significantly associated with higher odds of severe menstrual cycle irregularity with menstrual interval of greater than 3 months (2.67 [1.35-5.27]). Participants with sleep duration of ≤ 5 h a day with psychological stress, depressive mood, or suicidal ideation had higher odds of menstrual cycle irregularity (1.96 [1.26-3.05], 2.86 [1.50-5.44], and 2.25 [1.18-4.29]). This study suggests positive associations of mental health problems and short sleep duration with menstrual cycle irregularity among Korean female adults. Therefore, strategies to deal with psychological stress, depressive mood, and sleep duration are needed for improving the reproductive health of women suffering from menstrual disturbances.

Mutation breeding is largely performed by forward and reverse genetics-based approaches. In the latter, Target Induced Local Lesions IN Genomes (TILLING) can be used to screen mutants harboring mutations in a target gene whose function can be predicted with available functional genomic information. In TILLING, it is necessary to use an analytical system for accurate and efficient screening of target gene mutants among several randomly mutagenized lines. Therefore, we optimized a capillary electrophoresis-based TILLING system that can quickly and easily analyze many samples and confirmed its performance by applying it to pepper mutation populations. First, optimal conditions concerning heteroduplex DNA formation, type and concentration of endonucleases, and concentration, pooling depth, and size of PCR amplicons were determined in an analytical system using a capillary electrophoresis apparatus without labeled primers. The results showed that CelII endonuclease (Surveyor™) had higher sensitivity than CelI. While the recommended concentration in the manufacturer’s manual was 1×, we obtained higher sensitivity when the amount of PCR product and concentration of the endonucleases were at 180 ng and 0.5× for CelII and 120 ng and 2× for CelI. Meanwhile, the maximum pooling depth for DNA from individuals in mutant populations inversely correlated to PCR amplicon size. The limitation of DNA pooling was 4× for a 1872-bp amplicon, while at least 16× pooling was possible for a 672-bp amplicon. Using this optimized system, TILLING was performed on 2615 individuals from the mutant populations developed in a Korean pepper landrace, “Yuwolcho,” to screen lines bearing a mutation in CCS (capsanthin/capsorbin synthase). We were able to select a mutant line with a substituted base pair in the translational start codon of CCS. The capillary electrophoresis-based TILLING system optimized in this study is expected to be useful in practical applications for reverse genetics-based breeding and functional genomics studies.

This study was initiated to develop a model specialized to conduct human risk assessments (HRAs) of abandoned metal mine areas in Korea. The Korean guideline (KG) model used in study was formulated via modification of the original Korean guidelines on HRAs of soil contamination. In addition, the newly developed model was applied to the HRAs of two abandoned metal mines contaminated with arsenic (As) and heavy metals (Cd, Cu, Pb, and Zn). The results of the KG model were compared with those of two internationally renowned models [Contaminated land exposure assessment (CLEA) and CSOIL models]. The HRA results of the three models indicated that the areas of concern were unsafe when it came to both carcinogenic and non-carcinogenic hazards. Furthermore, the hazards in both areas were mostly attributed to As and the predominant exposure pathways were identified as crop intake in the KG model and surface soil dermal contact in CLEA and CSOIL models. Accordingly, measures to protect against As exposure should be established immediately to prevent adverse health effects on inhabitants in these areas. A comparison of HRA results revealed significant differences between KG, CLEA, and CSOIL models due to the various types of exposure pathways, contaminants, and input data, such as exposure factors and receptor parameters. This study suggests that set-up of an exposure scenario is crucial for the successful performance of HRAs, and the most relevant HRA model should be deliberately selected to attain risk assessment goals.

Background/aims Several previous studies suggest that eradication of Helicobacter pylori (H. pylori) leads to the disappearance of gastric hyperplastic polyps. However, little is known about the effect of H. pylori status and eradication on the recurrence of gastric polyps after endoscopic removal. Here, we investigated the recurrence of gastric polyps according to the final H. pylori status in patients who underwent endoscopic removal of gastric hyperplastic polyps. Methods Between January 2011 and December 2016, patients who underwent endoscopic removal of gastric hyperplastic polyps and were followed-up for more than two months were enrolled. The success of H. pylori eradication was assessed by histology and rapid urease test or urea breath test, at least 4 weeks after the completion of eradication treatment. At follow-up, the recurrence of gastric polyp was evaluated via esophagogastroduodenoscopy. Results Seventy-nine patients were enrolled. During the mean follow-up period of 16.4 months, the recurrence rate of gastric polyp was 25.3%. Among those who received H. pylori eradication therapy, the H. pylori persistent group showed a higher recurrence of polyp than the H. pylori eradicated group; but there was no statistical significance (42.9% vs. 21.7%, p=0.269). Regarding the final H. pylori infection status, the recurrence rate of gastric polyps was significantly higher in the H. pylori positive group than in the H. pylori negative group (42.9% vs. 18.9%, p=0.031). In multivariate analysis, the final H. pylori infection status was a significant risk factor for gastric polyp recurrence after endoscopic removal. Conclusions The final positive H. pylori infection status is significantly associated with higher recurrence of gastric hyperplastic polyps after endoscopic removal.

The effects of winglet offset distance, winglet coverage, and winglet cross section on the over-tip leakage loss for the plane tip have been investigated experimentally in a turbine blade cascade for a tip gap height-to-span ratio of h/s = 1.36 %. The results show that the over-tip leakage loss for the full coverage winglet increases steeply with increasing the winglet offset distance. This loss generation is attributed to flow disturbances over the forward-facing and backward-facing steps within the tip gap. The winglet flush mounted to the tip surface provides the best result. With the leading edge winglet portion or without it, the both-side winglet always provides better aerodynamic performance than the corresponding pressure-side winglet or suction-side winglet. Longer coverage of the both-side winglet leads to lower loss. Therefore, the full coverage winglet performs best in the loss reduction for the plane tip. In general, thinner winglet leads to better aerodynamic result, and the winglet cross section having a slant bottom surface with the smallest thickness at its outer end is recommended.

OB associations are the prevailing star forming sites in the Galaxy. Up to now, the process of how OB associations were formed remained a mystery. A possible process is self-regulating star formation driven by feedback from massive stars. However, although a number of observational studies uncovered various signposts of feedback-driven star formation, the effectiveness of such feedback has been questioned. Stellar and gas kinematics is a promising tool to capture the relative motion of newborn stars and gas away from ionizing sources. We present high-resolution spectroscopy of stars and gas in the young open cluster NGC 1893. Our findings show that newborn stars and the tadpole nebula Sim 130 are moving away from the central cluster containing two O-type stars, and that the timescale of sequential star formation is about 1 Myr within a 9 parsec distance. The newborn stars formed by feedback from massive stars account for at least 18 per cent of the total stellar population in the cluster, suggesting that this process can play an important role in the formation of OB associations. These results support the self-regulating star formation model., Comment: 13 pages, 7 figures, 3 tables, accepted for publication in MNRAS

Aim We aimed to explore the role of the diagnostic accuracy of F-18 fluorodeoxyglucose positron emission tomography (F-18 FDG PET) or positron emission tomography/computed tomography (PET/CT) for prediction of malignant potential of gastrointestinal stromal tumor (GIST) through a systematic review and meta-analysis. Methods The MEDLINE, EMBASE, and Cochrane Library database, from the earliest available date of indexing through May 31, 2017, were searched for studies evaluating the diagnostic performance of F-18 FDG PET or PET/CT for prediction of malignant potential of GIST. We determined the sensitivities and specificities across studies, calculated positive and negative likelihood ratios (LR+ and LR-), and constructed summary receiver operating characteristic curves. Results Across 7 studies (188 patients), the pooled sensitivity for F-18 FDG PET or PET/CT was 0.88 (95% CI; 0.80-0.94) without heterogeneity (χ2=6.15, p=0.72) and a pooled specificity of 0.88 (95% CI; 0.75-0.94) with heterogeneity (χ2=23.2, p= 0.01). Likelihood ratio (LR) syntheses gave an overall positive likelihood ratio (LR+) of 7.2 (95% CI; 3.3-15.3) and negative likelihood ratio (LR-) of 0.13 (95% CI; 0.07-0.24). The pooled DOR was 54 (95% CI; 16-181). Conclusion F-18 FDG PET or PET/CT demonstrated good sensitivity and specificity for the prediction of malignant potential of GIST. At present, the literature regarding the use of F-18 FDG PET or PET/CT for the prediction of malignant potential of GIST remains still limited; thus, further large multicenter studies would be necessary to substantiate the diagnostic accuracy of F-18 FDG PET or PET/CT prediction of malignant potential of GIST.

We aimed to investigate the value of breast magnetic resonance (MR) imaging and positron emission tomography-computed tomography (PET/CT) in predicting advanced axillary lymph node (ALN) metastases (ypN2-3) after neoadjuvant chemotherapy (NAC) in invasive ductal carcinoma patients. A total of 108 patients with invasive ductal carcinoma underwent breast MR imaging and PET/CT both before and after NAC (termed initial staging and restaging, respectively). The number of positive ALNs and the short diameter (SD) of the largest ALN on breast MR imaging and maximal standardized uptake value (SUVmax) in the ALNs on PET/CT were evaluated. Odds ratio (OR) for prediction of advanced ALN metastases was calculated. The negative predictive value (NPV) of restaging imaging for exclusion of advanced ALN metastases was also calculated. Patients with advanced ALN metastases were more likely to have a higher number (≥2) of positive LNs (OR, 8.06; P = 0.015) on restaging MR imaging. No clinico-pathological factors were significantly associated with advanced ALN metastases. With restaging MR imaging, PET/CT, and MR imaging plus PET/CT, the NPV for excluding advanced ALN metastases was 97.3%, 94.4%, and 100.0%. A higher number of positive ALNs on restaging MR imaging was an independent predictor for advanced ALN metastases after NAC.

Radioactive-iodine (RAI) therapy is typically unprevailing as anaplastic thyroid cancer (ATC) management, owing to the decrease in the endogenous sodium iodide symporter (NIS) expression. Therefore, new strategies for NIS re-induction are required to improve the efficacy of RAI therapy in ATC. In this study, we developed a novel high-throughput NIS enhancer screening platform using a dual reporter gene system to identify a potent tyrosine kinase inhibitor (TKI) and selected a new hit compound, K905-0266 TKI. The effects of K905-0266 TKI treatment was validated as RAI accumulation, changes in signalling pathway related to thyroid pathogenesis, and cytotoxicity of RAI depending on re-induction of endogenous NIS expression in ATC. Furthermore, we evaluated enhancement of NIS promoter and therapeutic efficacy of RAI in ATC tumour xenograft mice. After K905-0266 TKI treatment, the expression of endogenous NIS was significantly increased, while phosphorylated-ERK was decreased. In addition, the thyroid-metabolising protein expressions were upregulated and increased of RAI accumulation and its therapeutic effects in ATC. Moreover, K905-0266 TKI increased therapeutic efficacy of RAI in ATC tumour in vivo. In conclusion, we successfully established a novel high-throughput NIS enhancer screening platform to excavate a NIS enhancer and identified K905-0266 TKI among TKI candidates and it's proven to increase the endogenous NIS expression and therapeutic efficacy of RAI in ATC. These findings suggest that a novel high-throughput NIS enhancer screening platform is useful for selecting of NIS promoter enhancers. In addition, K905-0266 TKI can be used to re-induce endogenous NIS expression and recover RAI therapy in ATC.

Here, we report a new concept of both the adhesive manner and material, named “adhesive leaf (AL),” based on the leaf of the plant Heteropanax fragrans. The treatment of the corona discharge on the leaf surface can cause the nano-/microdestruction of the leaf epidermis, resulting in an outward release of sap. The glucose-containing sap provided the AL with a unique ability to stick to various substrates such as steel, polypropylene, and glass. Moreover, we reveal that the AL adhesion strength depends on the AL size, as well as the corona-discharge intensity. Conventional adhesives, such as glue and bond, lose their adhesive property and leave dirty residues upon the removal of the attached material. Unlike the conventional methods, the AL is advantageous as it can be repeatedly attached and detached thoroughly until the sap liquid is exhausted; its adhesive ability is maintained for at least three weeks at room temperature. Our findings shed light on a new concept of a biodegradable adhesive material that is created by a simple surface treatment.

Paper fluidics has recently offered an approach to precisely guide liquid flow in analytical devices with a low-cost regime. Multiple paper layers expand the capability of analytical devices to handle multiple samples as well as multiple detections simultaneously. Here we present a novel inexpensive cut-and-insert method to achieve a well-controlled even distribution of liquid in multi-channel three-dimensional (3D) paper-based analytical devices. A novel vacuum-driven poly dimethyl siloxane (PDMS) stamping method to pattern hydrophobic barriers in the filter paper enables rapid fabrication and assembly of microfluidic paper-based analytical devices (μ-PADs). The cut-and-insert assembly method facilitates more efficient fluid transfer than conventional O2 plasma-assisted overlapped channel binding, due to the strong physical contact between connected layers. The liquid transfer starts from the center region where two inserted layers are overlapped, and thus the presented method enables consistent liquid transfer independent of the angles of connected fluidic paths. Consequently, the angles between the connected μ-PAD strips as well as the 3D distance for the fluid transfer can be freely adjusted as needed. Also, multiple strips can be easily connected in series or in parallel. For example, perpendicularly connected bended paper channels guide upward and then lateral liquid flows by capillary action. Three important assays, i.e. nitrite 0 to 2 ppm, pH 1 to 10, and glucose 0 to 0.22 molL−1, were successfully implemented and measured simultaneously using a device with four strips connected in parallel.

Mesenchymal stem cells (MSCs) show therapeutic effects in various types of diseases. MSCs have been shown to migrate towards inflamed or cancerous tissues, and visualized after sacrificing the animal. MSCs are able to deliver drugs to target cells, and are an ideal candidate for cancer therapy. The purpose of this study was to track the migration of MSCs in tumor-bearing mice; MSCs were also used as drug delivery vehicles. Human breast cancer cells (MDA-MB-231) and anaplastic thyroid cancer cells (CAL62) were transduced with lentiviral particles, to express the Renilla luciferase and mCherry (mCherry-Rluc) reporter genes. Human bone marrow-derived MSCs were transduced with lentiviral particles, to express the firefly luciferase and enhanced green fluorescence protein (Fluc2-eGFP) reporter genes (MSC/Fluc). Luciferase activity of the transduced cells was measured by bioluminescence imaging (BLI). Further in vitro migration assays were performed to confirm cancer cells conditioned medium dependent MSC and doxorubicin (DOX) treated MSC migration. MSCs were loaded with DOX, and their therapeutic effects against the cancer cells were studied in vitro. In vivo MSC/Fluc migration in mice having thyroid or breast cancer xenografts was evaluated after systemic injection. Rluc activity of CAL62/Rluc (R2=0.911), MDA-MB-231/Rluc (R2=0.934) cells and Fluc activity of MSC/Fluc (R2=0.91) cells increased with increasing cell numbers, as seen by BLI. eGFP expression of MSC/Fluc was confirmed by confocal microscopy. Similar migration potential was observed between MSC/Fluc and naive MSCs in migration assay. DOX treated MSCs migration was not decreased compared than MSCs. Migration of the systemically injected MSC/Fluc cells into tumor xenografts (thyroid and breast cancer) was visualized in animal models (p

Background: The first aim of our study was to determine whether cortical 18F-florbetaben retention was different between healthy controls and idiopathic normal-pressure hydrocephalus (INPH) patients. Our second aim was to investigate whether there were any relationships between 18F-florbetaben retention and either hippocampal volume or clinical symptoms in INPH patients. Methods: Seventeen patients diagnosed with INPH and 8 healthy controls underwent studies with magnetic resonance imaging and 18F-florbetaben positron emission tomography imaging. Results: Automated region-of-interest analysis showed significant increases in 18F-florbetaben uptake in several brain regions in INPH patients compared to control subjects, with especially remarkable increases in the frontal (bilateral), parietal (bilateral), and occipital (bilateral) cortices. In the INPH group, right hippocampal volume was found to be negatively correlated with right frontal 18F-florbetaben retention. Korean-Mini Mental State Examination scores negatively correlated with right occipital 18F-florbetaben retention. Higher 18F-florbetaben retention correlated significantly with a higher Clinical Dementia Rating Scale score in the right occipital cortex. Conclusions: Our results indicate that INPH might be a disease exhibiting a characteristic pattern of cortical 18F-florbetaben retention. 18F-florbetaben retention in the frontal cortex may be related to hippocampal neuronal degeneration. Our findings may also help us understand the potential pathophysiology of cognitive impairments associated with INPH.

Here, we demonstrate a powerful method to discriminate DNA mismatches at single-nucleotide resolution from 0 to 5 mismatches (χ0 to χ5) using Kelvin probe force microscopy (KPFM). Using our previously developed method, we quantified the surface potentials (SPs) of individual DNA-capped nanoparticles (DCNPs, ∼100 nm). On each DCNP, DNA hybridization occurs between ∼2200 immobilized probe DNA (pDNA) and target DNA with mismatches (tDNA, ∼80 nM). Thus, each DCNP used in the bioassay (each pDNA-tDNA interaction) corresponds to a single ensemble in which a large number of pDNA-tDNA interactions take place. Moreover, one KPFM image can scan at least dozens of ensembles, which allows statistical analysis (i.e., an ensemble average) of many bioassay cases (ensembles) under the same conditions. We found that as the χn increased from χ0 to χ5 in the tDNA, the average SP of dozens of ensembles (DCNPs) was attenuated owing to fewer hybridization events between the pDNA and the tDNA. Remarkably, the SP attenuation vs. the χn showed an inverse-linear correlation, albeit the equilibrium constant for DNA hybridization exponentially decreased asymptotically as the χn increased. In addition, we observed a cascade reaction at a 100-fold lower concentration of tDNA (∼0.8 nM); the average SP of DCNPs exhibited no significant decrease but rather split into two separate states (no-hybridization vs. full-hybridization). Compared to complementary tDNA (i.e., χ0), the ratio of no-hybridization/full-hybridization within a given set of DCNPs became ∼1.6 times higher in the presence of tDNA with single mismatches (i.e., χ1). The results imply that our method opens new avenues not only in the research on the DNA hybridization mechanism in the presence of DNA mismatches but also in the development of a robust technology for DNA mismatch detection.