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1.
Sensors (Basel) ; 21(11)2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34064274

RESUMO

Owing to the increasing use of permeable pavement, there is a growing need for studies that can improve its design and durability. One of the most important factors that can reduce the functionality of permeable pavement is the clogging issue. Field experiments for investigating the clogging potential are relatively expensive owing to the high-cost testing equipment and materials. Moreover, a lot of time is required for conducting real physical experiments to obtain physical properties for permeable pavement. In this paper, to overcome these limitations, we propose a three-dimensional microstructure reconstruction framework based on 3D-IDWGAN with an enhanced gradient penalty, which is an image-based computational system for clogging analysis in permeable pavement. Our proposed system first takes a two-dimensional image as an input and extracts latent features from the 2D image. Then, it generates a 3D microstructure image through the generative adversarial network part of our model with the enhanced gradient penalty. For checking the effectiveness of our system, we utilize the reconstructed 3D image combined with the numerical method for pavement microstructure analysis. Our results show improvements in the three-dimensional image generation of the microstructure, compared with other generative adversarial network methods, and the values of physical properties extracted from our model are similar to those obtained via real pavement samples.

2.
Sensors (Basel) ; 20(2)2020 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-31963592

RESUMO

Indoor positioning techniques, owing to received signal strength indicator (RSSI)-based sensors, can provide useful trajectory-based services. These services include user movement analytics, next-to-visit recommendation, and hotspot detection. However, the value of RSSI is often disturbed due to obstacles in indoor environment, such as doors, walls, and furnitures. Therefore, many indoor positioning techniques still extract an invalid trajectory from the disturbed RSSI. An invalid trajectory contains distant or impossible consecutive positions within a short time, which is unlikely in a real-world scenario. In this study, we enhanced indoor positioning techniques with movement constraints on BLE (Bluetooth Low Energy) RSSI data to prevent an invalid semantic indoor trajectory. The movement constraints ensure that a predicted semantic position cannot be far apart from the previous position. Furthermore, we can extend any indoor positioning technique using these movement constraints. We conducted comprehensive experimental studies on real BLE RSSI datasets from various indoor environment scenarios. The experimental results demonstrated that the proposed approach effectively extracts valid indoor semantic trajectories from the RSSI data.

3.
Int J Mol Sci ; 21(20)2020 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-33081273

RESUMO

Copper is an essential metal ion that performs many physiological functions in living organisms. Deletion of Afmac1, which is a copper-responsive transcriptional activator in A. fumigatus, results in a growth defect on aspergillus minimal medium (AMM). Interestingly, we found that zinc starvation suppressed the growth defect of the Δafmac1 strain on AMM. In addition, the growth defect of the Δafmac1 strain was recovered by copper supplementation or introduction of the CtrC gene into the Δafmac1 strain. However, chelation of copper by addition of BCS to AMM failed to recover the growth defect of the Δafmac1 strain. Through Northern blot analysis, we found that zinc starvation upregulated CtrC and CtrA2, which encode membrane copper transporters. Interestingly, we found that the conserved ZafA binding motif 5'-CAA(G)GGT-3' was present in the upstream region of CtrC and CtrA2 and that mutation of the binding motif led to failure of ZafA binding to the upstream region of CtrC and upregulation of CtrC expression under zinc starvation. Furthermore, the binding activity of ZafA to the upstream region of CtrC was inversely proportional to the zinc concentration, and copper inhibited the binding of ZafA to the upstream region of CtrC under a low zinc concentration. Taken together, these results suggest that ZafA upregulates copper metabolism by binding to the ZafA binding motif in the CtrC promoter region under low zinc concentration, thus regulating copper homeostasis. Furthermore, we found that copper and zinc interact in cells to maintain metal homeostasis.


Assuntos
Aspergillus fumigatus/metabolismo , Cobre/metabolismo , Zinco/metabolismo , Aspergillus fumigatus/genética , Aspergillus fumigatus/crescimento & desenvolvimento , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Cobre/deficiência , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Estresse Fisiológico , Regulação para Cima , Zinco/deficiência
4.
Sensors (Basel) ; 18(10)2018 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-30262769

RESUMO

The new standard oneM2M (one machine-to-machine) aims to standardize the architecture and protocols of Internet of Things (IoT) middleware for better interoperability. Although the standard seems promising, it lacks several features for efficiently searching and retrieving IoT data which satisfy users' intentions. In this paper, we design and develop a oneM2M-based query engine, called OMQ, that provides a real-time processing over IoT data streams. For this purpose, we define a query language which enables users to retrieve IoT data from data sources using JavaScript Object Notation (JSON). We also propose efficient query processing algorithms which utilizes the oneM2M architecture consisting of two nodes: (1) the IoT node and (2) the infrastructure node. IoT nodes of OMQ are mainly sensor devices execute user queries the aggregate, transform and filter operators, whereas the infrastructure node handles the join operator of user queries. Since the query processing algorithms are implemented as the hybrid infrastructure-edge processing, user queries can be executed efficiently in each IoT node rather than only in the infrastructure node. Thus, our OMQ system reduces the query processing time and the network bandwidth. We conducted a comprehensive evaluation of OMQ using a real and a synthetic data set. Experimental results demonstrate the feasibility and efficiency of OMQ system for executing queries and transferring data from each IoT node.

5.
Sensors (Basel) ; 18(4)2018 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-29587366

RESUMO

In this paper, we are interested in computing ZIP code proximity from two perspectives, proximity between two ZIP codes (Ad-Hoc) and neighborhood proximity (Top-K). Such a computation can be used for ZIP code-based target marketing as one of the smart city applications. A naïve approach to this computation is the usage of the distance between ZIP codes. We redefine a distance metric combining the centroid distance with the intersecting road network between ZIP codes by using a weighted sum method. Furthermore, we prove that the results of our combined approach conform to the characteristics of distance measurement. We have proposed a general and heuristic approach for computing Ad-Hoc proximity, while for computing Top-K proximity, we have proposed a general approach only. Our experimental results indicate that our approaches are verifiable and effective in reducing the execution time and search space.

6.
Sensors (Basel) ; 17(10)2017 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-28946633

RESUMO

In the vehicular networks, the real-time video reporting service is used to send the recorded videos in the vehicle to the cloud. However, when facilitating the real-time video reporting service in the vehicular networks, the usage of the fourth generation (4G) long term evolution (LTE) was proved to suffer from latency while the IEEE 802.11p standard does not offer sufficient scalability for a such congested environment. To overcome those drawbacks, the fifth-generation (5G)-enabled vehicular network is considered as a promising technology for empowering the real-time video reporting service. In this paper, we note that security and privacy related issues should also be carefully addressed to boost the early adoption of 5G-enabled vehicular networks. There exist a few research works for secure video reporting service in 5G-enabled vehicular networks. However, their usage is limited because of public key certificates and expensive pairing operations. Thus, we propose a secure and lightweight protocol for cloud-assisted video reporting service in 5G-enabled vehicular networks. Compared to the conventional public key certificates, the proposed protocol achieves entities' authorization through anonymous credential. Also, by using lightweight security primitives instead of expensive bilinear pairing operations, the proposed protocol minimizes the computational overhead. From the evaluation results, we show that the proposed protocol takes the smaller computation and communication time for the cryptographic primitives than that of the well-known Eiza-Ni-Shi protocol.

7.
Sensors (Basel) ; 17(10)2017 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-28946679

RESUMO

One of the crucial problems for taxi drivers is to efficiently locate passengers in order to increase profits. The rapid advancement and ubiquitous penetration of Internet of Things (IoT) technology into transportation industries enables us to provide taxi drivers with locations that have more potential passengers (more profitable areas) by analyzing and querying taxi trip data. In this paper, we propose a query processing system, called Distributed Profitable-Area Query (DISPAQ) which efficiently identifies profitable areas by exploiting the Apache Software Foundation's Spark framework and a MongoDB database. DISPAQ first maintains a profitable-area query index (PQ-index) by extracting area summaries and route summaries from raw taxi trip data. It then identifies candidate profitable areas by searching the PQ-index during query processing. Then, it exploits a Z-Skyline algorithm, which is an extension of skyline processing with a Z-order space filling curve, to quickly refine the candidate profitable areas. To improve the performance of distributed query processing, we also propose local Z-Skyline optimization, which reduces the number of dominant tests by distributing killer profitable areas to each cluster node. Through extensive evaluation with real datasets, we demonstrate that our DISPAQ system provides a scalable and efficient solution for processing profitable-area queries from huge amounts of big taxi trip data.

8.
Sensors (Basel) ; 16(9)2016 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-27563900

RESUMO

The escalation of traffic congestion in urban cities has urged many countries to use intelligent transportation system (ITS) centers to collect historical traffic sensor data from multiple heterogeneous sources. By analyzing historical traffic data, we can obtain valuable insights into traffic behavior. Many existing applications have been proposed with limited analysis results because of the inability to cope with several types of analytical queries. In this paper, we propose the QET (querying and extracting timeline information) system-a novel analytical query processing method based on a timeline model for road traffic sensor data. To address query performance, we build a TQ-index (timeline query-index) that exploits spatio-temporal features of timeline modeling. We also propose an intuitive timeline visualization method to display congestion events obtained from specified query parameters. In addition, we demonstrate the benefit of our system through a performance evaluation using a Busan ITS dataset and a Seattle freeway dataset.

9.
Biomater Res ; 27(1): 71, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37468961

RESUMO

BACKGROUND: Glial scar formation is a reactive glial response confining injured regions in a central nervous system. However, it remains challenging to identify key factors formulating glial scar in response to glioblastoma (GBM) due to complex glia-GBM crosstalk. METHODS: Here, we constructed an astrocytic scar enclosing GBM in a human assembloid and a mouse xenograft model. GBM spheroids were preformed and then co-cultured with microglia and astrocytes in 3D Matrigel. For the xenograft model, U87-MG cells were subcutaneously injected to the Balb/C nude female mice. RESULTS: Additional glutamate was released from GBM-microglia assembloid by 3.2-folds compared to GBM alone. The glutamate upregulated astrocytic monoamine oxidase-B (MAO-B) activity and chondroitin sulfate proteoglycans (CSPGs) deposition, forming the astrocytic scar and restricting GBM growth. Attenuating scar formation by the glutamate-MAO-B inhibition increased drug penetration into GBM assembloid, while reducing GBM confinement. CONCLUSIONS: Taken together, our study suggests that astrocytic scar could be a critical modulator in GBM therapeutics.

10.
Nat Metab ; 5(9): 1506-1525, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37653043

RESUMO

The lateral hypothalamic area (LHA) regulates food intake and energy balance. Although LHA neurons innervate adipose tissues, the identity of neurons that regulate fat is undefined. Here we show that GABRA5-positive neurons in LHA (GABRA5LHA) polysynaptically project to brown and white adipose tissues in the periphery. GABRA5LHA are a distinct subpopulation of GABAergic neurons and show decreased pacemaker firing in diet-induced obesity mouse models in males. Chemogenetic inhibition of GABRA5LHA suppresses fat thermogenesis and increases weight gain, whereas gene silencing of GABRA5 in LHA decreases weight gain. In the diet-induced obesity mouse model, GABRA5LHA are tonically inhibited by nearby reactive astrocytes releasing GABA, which is synthesized by monoamine oxidase B (Maob). Gene silencing of astrocytic Maob in LHA facilitates fat thermogenesis and reduces weight gain significantly without affecting food intake, which is recapitulated by administration of a Maob inhibitor, KDS2010. We propose that firing of GABRA5LHA suppresses fat accumulation and selective inhibition of astrocytic GABA is a molecular target for treating obesity.


Assuntos
Astrócitos , Obesidade , Masculino , Animais , Camundongos , Aumento de Peso , Neurônios , Modelos Animais de Doenças , Monoaminoxidase , Ácido gama-Aminobutírico
11.
AJR Am J Roentgenol ; 199(2): 349-59, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22826396

RESUMO

OBJECTIVE: The purpose of this article is to assess CT enhancement patterns of hepatocellular carcinoma (HCC) within 1 month after transarterial chemoembolization (TACE) using drug-eluting beads and to determine whether enhancement patterns may be useful for predicting local tumor progression. MATERIALS AND METHODS: Forty-one patients with 50 HCCs underwent CT within 1 month after TACE with drug-eluting beads. Two blinded readers independently reviewed the arterial phase images and classified enhancement patterns as follows: no enhancement, peripheral ring enhancement, and peripheral nodulelike enhancement. Enhancement patterns were correlated with time to tumor progression of enhancing tissue by log-rank test. RESULTS: In the group with no enhancement, 92.3% (24/26) had not progressed and 7.7% (2/26) showed progression; for peripheral ring enhancement, 83.3% (10/12) had not progressed and 16.7% (2/12) showed progression; and for peripheral nodulelike enhancement, 16.7% (2/12) had not progressed and 83.3% (10/12) showed progression. The time to progression of enhancing tissue was significantly different between the group with no enhancement plus peripheral ring enhancement and the group with peripheral nodulelike enhancement (p < 0.001). CONCLUSION: Analysis of enhancement patterns at the arterial phase of the first follow-up CT after TACE with drug-eluting beads is helpful for predicting progression of treated HCC.


Assuntos
Antibióticos Antineoplásicos/administração & dosagem , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/tratamento farmacológico , Quimioembolização Terapêutica/métodos , Doxorrubicina/administração & dosagem , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/tratamento farmacológico , Microesferas , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Distribuição de Qui-Quadrado , Meios de Contraste , Progressão da Doença , Feminino , Humanos , Iohexol/análogos & derivados , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Interpretação de Imagem Radiográfica Assistida por Computador , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
12.
Mol Imaging Biol ; 21(5): 917-925, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-30719695

RESUMO

PURPOSE: 2-Deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) accumulation in inflammatory lesions can confound the diagnosis of cancer. In this study, we investigated [18F]FDG accumulation and efflux in relation to the genes and proteins involved in glucose metabolism in murine inflammation and cancer models. PROCEDURES: [18F]FDG accumulation and [18F]FDG efflux were measured in cancer cells (breast cancer, glioma, thyroid cancer, and hepatoma cells) and RAW 264.7 cells (macrophages) activated with lipopolysaccharide (LPS). The levels of mRNA expression were measured by real-time quantitative PCR (qPCR). The expression of glucose metabolism-related proteins was detected by western blotting. Dynamic [18F]FDG positron emission tomography-computed tomography (PET/CT) images were acquired for 2 h in tumor-bearing BALB/c nude mice and inflammatory mice induced by turpentine oil. RESULTS: [18F]FDG accumulation in MDA-MB-231 (breast cancer) increased with time, but that of HepG2 (hepatoma) reached a constant level after 120 min. [18F]FDG efflux in HepG2 was faster than that in MDA-MB-231. HepG2 strongly expressed glucose-6-phosphatase (G6Pase) compared with MDA-MB-231. [18F]FDG accumulation increased with time, and [18F]FDG efflux accelerated after the activation of RAW 264.7 cells. The expression levels of G6Pase, glucose transporter1 and glucose transporter3 (GLUT1 and GLUT3), and hexokinase II (HK II) increased after the activation of RAW 264.7 cells. [18F]FDG efflux in activated macrophages was faster than that in MDA-MB-231 cancer cells. MDA-MB-231 strongly expressed HK II protein compared with the activated RAW 264.7. In murine models, [18F]FDG accumulation in MDA-MB-231 cancer and inflammatory lesions increased with time, but that in HepG2 tumor increased until 20-30 min (SUVmeans ± SD (tumor/muscle), 3.0 ± 1.3) and then decreased (2.1 ± 0.9 at 110-120 min). CONCLUSIONS: There was no difference in the pattern of [18F]FDG accumulation with time in MDA-MB-231 tumors and inflammatory lesions. We found that [18F]FDG efflux accelerated in activated macrophages reflecting increased G6Pase expression after activation and lower expression of HK II protein than that in MDA-MB-231 cancer cells.


Assuntos
Fluordesoxiglucose F18/metabolismo , Glucose-6-Fosfatase/metabolismo , Inflamação/metabolismo , Neoplasias/metabolismo , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Glucose/metabolismo , Humanos , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Células RAW 264.7
14.
Cardiovasc Intervent Radiol ; 40(5): 744-749, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28184958

RESUMO

PURPOSE: To evaluate the effect of bariatric arterial embolization (BAE) with non-spherical polyvinyl alcohol (PVA) particles on systemic ghrelin levels, weight change, and gastric ulceration risk in a swine model. MATERIALS AND METHODS: From March 2014 to February 2015, ten healthy swine were used in the study (mean weight 31.5 kg; range 24.0-41.5 kg). The animals were randomly assigned to two groups: the embolized group (n = 5) in which BAE was performed and the control group (n = 5). In the embolized group, BAE was performed by selectively infusing 150-250 or 50-150 µm PVA into the gastric arteries that supplied the fundus of the stomach. In the control group, a sham procedure was performed with saline infusion. Plasma ghrelin levels were prospectively obtained at baseline and every 2 weeks thereafter. Endoscopy was performed 3 weeks after BAE to see whether any gastric ulcer occurred. To determine the durability of the occluded arteries, repeated celiac trunk angiography was performed 8 weeks after BAE. Then, all the swine were killed and necropsies were performed. RESULTS: The mean post-procedure ghrelin value decreased by 370.0 pg/mL in the embolized group at week 3 (mean 536.0 ± 334.3 pg/mL) and week 5 (mean 515.0 ± 150.0 pg/mL, p < 0.05) relative to baseline (880.0 ± 559.5 pg/mL), respectively, but ghrelin levels were not significantly decreased between the embolized and control groups. There was a significant body weight change as follows: 35.1 ± 9.5 to 46.6 ± 15.7 kg and 31.8 ± 5.8 to 41.2 ± 6.6 kg at baseline and endpoint in the control and embolized groups, respectively (p < 0.05). However, the difference between groups was not significant at endpoint. In the embolized group, ulcerations were identified in three animals (60%) and the recanalization of the embolized arteries was noted on follow-up angiography in three animals (60%), respectively. CONCLUSION: BAE with PVA particles can transiently suppress ghrelin levels in embolized animals, but levels are not significantly different compared to controls. Stomach ulcerations were identified in 60% of the embolized animals.


Assuntos
Bariatria , Embolização Terapêutica/métodos , Mucosa Gástrica/metabolismo , Grelina/sangue , Álcool de Polivinil/administração & dosagem , Estômago/irrigação sanguínea , Angiografia , Animais , Peso Corporal , Embolização Terapêutica/efeitos adversos , Modelos Animais , Estômago/diagnóstico por imagem , Úlcera Gástrica/etiologia , Suínos
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