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Plants are constantly challenged by various environmental stresses, including high salinity and drought, and they have evolved defense mechanisms to counteract the deleterious effects of these stresses. The plant hormone ABA regulates plant growth and developmental processes and mediates abiotic stress responses. Here, we report the identification and characterization of a novel CaWDP1 (Capsicum annuum) protein. The expression of CaWDP1 in pepper leaves was induced by ABA, drought and NaCl treatments, suggesting its role in the abiotic stress response. CaWDP1 proteins show conserved sequence homology with other known WDP1 proteins, and they are localized in the nucleus and cytoplasm. We generated CaWDP1-silenced peppers via virus-induced gene silencing (VIGS). We evaluated the responses of these CaWDP1-silenced pepper plants and CaWDP1-overexpressing (OX) transgenic Arabidopsis plants to ABA and drought. CaWDP1-silenced pepper plants displayed enhanced tolerance to drought stress, and this was characterized by low levels of leaf water loss in the drought-treated leaves. In contrast to CaWDP1-silenced plants, CaWDP1-OX plants exhibited an ABA-hyposensitive and drought-susceptible phenotype, which was accompanied by high levels of leaf water loss, low leaf temperatures, increased stomatal pore size and low expression levels of stress-responsive genes. Our results indicate that CaWDP1, a novel pepper negative regulator of ABA, regulates the ABA-mediated defense response to drought stress.
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Ácido Abscísico/metabolismo , Capsicum/fisiologia , Secas , Proteínas de Plantas/metabolismo , Ácido Abscísico/farmacologia , Arabidopsis/genética , Capsicum/efeitos dos fármacos , Capsicum/genética , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Germinação/efeitos dos fármacos , Germinação/fisiologia , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas , Salinidade , Plântula/efeitos dos fármacos , Plântula/fisiologia , Transdução de Sinais , Estresse FisiológicoRESUMO
The homologue of human YTHDF2, Ydr374c (Pho92), is the only protein that has a YTH (YT521-B homology) domain in Saccharomyces cerevisiae. Based on microarray analysis, genes involved in the phosphate signal transduction (PHO) pathway were up-regulated in the Δpho92 strain, as were genes regulated by Pho4, which is an important transcription factor in the PHO pathway. To identify the exact mechanism of Pho92 action with respect to phosphate metabolism, we investigated the effect of Pho92 on PHO4 expression. The half-life of PHO4 mRNA was increased in the Δpho92 strain; this phenotype was also observed in the deletion mutants UPF1 and POP2, which are components of the NMD (nonsense-mediated decay) pathway and the Pop2-Ccr4-Not deadenylase complex respectively. Pho92 interacts physically with Pop2 of the Pop2-Ccr4-Not deadenylase complex. Furthermore, Pho92 binding to the 3'-UTR of PHO4 was dependent on the phosphate concentration. Deletion of the PHO4 3'-UTR resulted in PHO4 mRNA resistance to Pho92-dependent degradation. The results of the present study indicate that Pho92 regulates Pho4 expression at the post-transcriptional level via the regulation of mRNA stability. Taken together, Pho92 participates in cellular phosphate metabolism, specifically via the regulation of PHO4 mRNA stability by binding to the 3'-UTR in a phosphate-dependent manner.
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Proteínas de Ligação a DNA/metabolismo , Regulação Bacteriana da Expressão Gênica , Proteínas de Transporte de Fosfato/metabolismo , Fosfatos/metabolismo , RNA Bacteriano/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Regiões 3' não Traduzidas , Sequência de Aminoácidos , Sítios de Ligação , Sequência Conservada , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Humanos , Mutação , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/metabolismo , Degradação do RNAm Mediada por Códon sem Sentido , Proteínas de Transporte de Fosfato/química , Proteínas de Transporte de Fosfato/genética , Fatores de Processamento de RNA , Estabilidade de RNA , RNA Bacteriano/química , RNA Mensageiro/química , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética , Ribonucleases/química , Ribonucleases/metabolismo , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Homologia de Sequência de Aminoácidos , Fatores de Poliadenilação e Clivagem de mRNA/química , Fatores de Poliadenilação e Clivagem de mRNA/metabolismoRESUMO
Introduction: Relatively little research has explored non-Western women workers and their career transitions within their unique cultural contexts. Thus, more context-sensitive approaches to women's career trajectories are needed. Methods: Based on Bian and Wang's Career Decision Tree Model (2019) as a conceptual framework, the reasons for South Korean women workers' career transitions and influencing factors were explored using a qualitative approach with in-depth interviews with 35 South Korean women workers at various career stages. Results and Discussion: Their main motive of career transitions was difficulty maintaining their physical and mental health, which stemmed from their demanding work life. A typical issue, the burden of child rearing and family responsibilities, was also reported, but it was not the primary reason for their career transitions. Instead, the women workers often mentioned these responsibilities along with other reasons. Other reasons were unresolved career interests and expectations associated with their lack of career goals and preparation prior to joining the labor market. These factors led to significant changes in women's values and priorities along their career path, which finally triggered a decision to make a career transition. South Korean socio-cultural characteristics embedded in the South Korean women's personal and organizational lives provide insights on how to interpret the findings. Although on the surface some of our findings appeared to confirm previous studies on women's career transitions in Western-based literature, noteworthy differences were discovered when delving deeper into women's career transitions in the South Korean context.
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PURPOSE: This study aimed to examine the interrupting effect of social distancing (SD) on emergency department (ED) patients with ischemic heart disease (IHD), stroke, asthma, and suicide attempts by PM2.5 exposure in eight Korean megacities from 2017 to 2020. MATERIALS AND METHODS: The study used National Emergency Department Information System and AirKorea data. A total of 469014 patients visited EDs from 2017 to 2020. Interrupted time series analysis was employed to examine changes in the level and slope of the time series, relative risk, and confidence intervals (CIs) by PM2.5 exposure. The SD level was added to the sensitivity analysis. RESULTS: The interrupted time series analysis demonstrated a significant increase in the ratio of relative risk (RRR) of IHD patients in Seoul (RRR=1.004, 95% CI: 1.001, 1.006) and Busan (RRR=1.007, 95% CI: 1.002, 1.012) post-SD. Regarding stroke, only patients in Seoul exhibited a significant decrease post-SD (RRR=0.995, 95% CI: 0.991, 0.999). No significant changes were observed for asthma in any of the cities. In the case of suicide attempts, Ulsan demonstrated substantial pre-SD (RR=0.827, 95% CI: 0.732, 0.935) and post-SD (RRR=1.200, 95% CI: 1.057, 1.362) differences. CONCLUSION: While the interrupting effect of SD was not as pronounced as anticipated, this study did validate the effectiveness of SD in modifying health behaviors and minimizing avoidable visits to EDs in addition to curtailing the occurrence of infectious diseases.
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Asma , Serviço Hospitalar de Emergência , Isquemia Miocárdica , Material Particulado , Acidente Vascular Cerebral , Tentativa de Suicídio , Humanos , Asma/prevenção & controle , Asma/epidemiologia , Material Particulado/efeitos adversos , Tentativa de Suicídio/estatística & dados numéricos , Isquemia Miocárdica/prevenção & controle , Isquemia Miocárdica/epidemiologia , Acidente Vascular Cerebral/prevenção & controle , Acidente Vascular Cerebral/epidemiologia , Serviço Hospitalar de Emergência/estatística & dados numéricos , República da Coreia/epidemiologia , Masculino , Feminino , Distanciamento Físico , Análise de Séries Temporais Interrompida , Pessoa de Meia-Idade , Exposição Ambiental/efeitos adversosRESUMO
BACKGROUND/PURPOSE: Distal radius fractures (DRFs) account for approximately 18% of fractures in patients 65 years and older. While plain radiographs are standard, the value of high-resolution computed tomography (CT) for detailed imaging crucial for diagnosis, prognosis, and intervention planning, and increasingly recognized. High-definition 3D reconstructions from CT scans are vital for applications like 3D printing in orthopedics and for the utility of mobile C-arm CT in orthopedic diagnostics. However, concerns over radiation exposure and suboptimal image resolution from some devices necessitate the exploration of advanced computational techniques for refining CT imaging without compromising safety. Therefore, this study aims to utilize conditional Generative Adversarial Networks (cGAN) to improve the resolution of 3 mm CT images (CT enhancement). METHODS: Following institutional review board approval, 3 mm-1 mm paired CT data from 11 patients with DRFs were collected. cGAN was used to improve the resolution of 3 mm CT images to match that of 1 mm images (CT enhancement). Two distinct methods were employed for training and generating CT images. In Method 1, a 3 mm CT raw image was used as input with the aim of generating a 1 mm CT raw image. Method 2 was designed to emphasize the difference value between the 3 mm and 1 mm images; using a 3 mm CT raw image as input, it produced the difference in image values between the 3 mm and 1 mm CT scans. Both quantitative metrics, such as peak signal-to-noise ratio (PSNR), mean squared error (MSE), and structural similarity index (SSIM), and qualitative assessments by two orthopedic surgeons were used to evaluate image quality by assessing the grade (1~4, which low number means high quality of resolution). RESULTS: Quantitative evaluations showed that our proposed techniques, particularly emphasizing the difference value in Method 2, consistently outperformed traditional approaches in achieving higher image resolution. In qualitative evaluation by two clinicians, images from method 2 showed better quality of images (grade: method 1, 2.7; method 2, 2.2). And more choice was found in method 2 for similar image with 1 mm slice image (15 vs 7, p = 201). CONCLUSION: In our study utilizing cGAN for enhancing CT imaging resolution, the authors found that the method, which focuses on the difference value between 3 mm and 1 mm images (Method 2), consistently outperformed.
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Fraturas do Rádio , Tomografia Computadorizada por Raios X , Fraturas do Punho , Humanos , Redes Neurais de Computação , Fraturas do Rádio/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Fraturas do Punho/diagnóstico por imagemRESUMO
Autophagy in eukaryotes functions to maintain homeostasis by degradation and recycling of long-lived and unwanted cellular materials. Autophagy plays important roles in pathogenicity of various fungal pathogens, suggesting that autophagy is a novel target for development of antifungal compounds. Here, we describe bioluminescence resonance energy transfer (BRET)-based high-throughput screening (HTS) strategy to identify compounds that inhibit fungal ATG4 cysteine protease-mediated cleavage of ATG8 that is critical for autophagosome formation. We identified ebselen (EB) and its analogs ebselen oxide (EO) and 2-(4-methylphenyl)-1,2-benzisothiazol-3(2H)-one (PT) as inhibitors of fungal pathogens Botrytis cinerea and Magnaporthe oryzae ATG4-mediated ATG8 processing. The EB and its analogs inhibit spore germination, hyphal development, and appressorium formation in Ascomycota pathogens, B. cinerea, M. oryzae, Sclerotinia sclerotiorum and Monilinia fructicola. Treatment with EB and its analogs significantly reduced fungal pathogenicity. Our findings provide molecular insights to develop the next generation of antifungal compounds by targeting autophagy in important fungal pathogens.
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Ascomicetos , Magnaporthe , Oryza , Antifúngicos/farmacologia , Antifúngicos/metabolismo , Virulência , Autofagia , Proteínas Relacionadas à Autofagia/metabolismo , Doenças das Plantas/prevenção & controle , Doenças das Plantas/microbiologia , Proteínas Fúngicas/metabolismo , Esporos FúngicosRESUMO
The quality of pavements in tropical climates is negatively affected by the frequent wet and dry cycles during the rainy season, as well as by issues related to overloading from heavy trucks and traffic congestion. Contributing to this deterioration are factors such as acid rainwater, heavy traffic oils, and municipal debris. In light of these challenges, this study aims to assess the viability of a polymer-modified asphalt concrete mixture. This study investigates the feasibility of a polymer-modified asphalt concrete mixture with the addition of 6% crumb rubber powder from waste car tires and 3% epoxy resin to counter the harsh conditions of tropical climate weather. The study involved subjecting test specimens to five to 10 cycles of contaminated water (100% rainwater + 10% used oil from trucks), curing for 12 h, and air drying in a chamber of 50 °C for 12 h to simulate critical curing conditions. The specimens underwent fundamental laboratory performance tests such as the indirect tensile strength test, dynamic modulus test, four points bending test, and Cantabro test, as well as the double load condition in the Hamburg wheel tracking test to determine the effectiveness of the proposed polymer-modified material in actual conditions. The test results confirmed that the simulated curing cycles had a critical impact on the durability of the specimens, with the greater curing cycles leading to a significant drop in the strength of the material. For example, the TSR ratio of the control mixture dropped from 90% to 83% and 76% after five and 10 curing cycles, respectively. Meanwhile, the modified mixture showed a decrease from 93% to 88% and 85% under the same conditions. The test results revealed that the effectiveness of the modified mixture outperformed the conventional condition in all tests, with a more prominent impact observed under overload conditions. Under double conditions in the Hamburg wheel tracking test and a curing condition of 10 cycles, the maximum deformation of the control mixture sharply increased from 6.91 to 22.7 mm, whereas the modified mixture increased from 5.21 to 12.4 mm. Overall, the test results confirm the durability of the polymer-modified asphalt concrete mixture under harsh tropical climate conditions, promoting its application for sustainable pavements, especially in Southeast Asian countries.
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PURPOSE: To evaluate the relationship between interocular asymmetries of corneal hysteresis (CH) and visual field defects in Korean patients with glaucoma. METHODS: A total of 444 eyes from 222 participants with glaucoma in at least one eye were enrolled. CH was measured using an ocular response analyzer (Reichert Technologies Inc). Eyes of each participant were classified into "better eye" and "worse eye" based on the mean deviation (MD) value of visual field test. The correlation between interocular differences in intraocular pressure, axial length, central corneal thickness, CH, and MD values was evaluated using Spearman correlation analysis. To exclude the possible effect of antiglaucoma medication on corneal properties, additional analyses were performed on eyes without any glaucoma treatment at the time of CH measurement (treatment-naive group). RESULTS: Median (interquartile range) MD value was -3.71 dB (-6.87 to -1.30 dB) in the better eye and -10.20 dB (-16.32 to -5.62 dB) in the worse eye. When the correlation between the asymmetry of the MD value and asymmetry of intraocular pressure, axial length, central corneal thickness, and CH were evaluated, only interocular differences in CH were significantly associated with interocular differences in MD values (rho = 0.214, p = 0.001). Among the 222 participants, 60 (27.0%) were treatment-naive group. In these eyes, interocular differences in CH were also significantly associated with interocular differences in the MD values (rho = 0.285, p = 0.029). CONCLUSIONS: The interocular asymmetry of CH was significantly correlated with the interocular asymmetry of visual field defects in glaucoma.
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Córnea , Glaucoma de Ângulo Aberto , Glaucoma , Humanos , Córnea/fisiologia , Glaucoma/complicações , Glaucoma/diagnóstico , Glaucoma de Ângulo Aberto/complicações , Glaucoma de Ângulo Aberto/diagnóstico , Pressão Intraocular , Tonometria Ocular , Transtornos da Visão , Testes de Campo Visual , Campos VisuaisRESUMO
Rising traffic volume, heavy loads, and construction activities have raised concerns about expansion joint device damage. This study focuses on developing an innovative expansion joint using polymer-modified rubber asphalt as the filling material to enhance its service life. Styrene-butadiene-styrene (SBS) emerged as a suitable modifier for rubber-modified asphalt, significantly improving elasticity and adhesion. Through the strategic combination of 3- and 2-block linear SBS, the elasticity and adhesion properties were significantly improved, resulting in the formulation of a well-suited polymer-modified rubber asphalt binder. The developed asphalt binder exhibits impressive elastic recovery (61.1% to 66.1%), surpassing commercial products, with enhanced constructability and workability (15% to 21% viscosity reduction). The carefully engineered mastic asphalt mixture showcases self-leveling characteristics at a moderate 210 °C, addressing historical constructability challenges. Settlement is 40% less than traditional hot mix asphalt for surface layers, with improved moisture and stripping resistance, enhancing existing asphalt plug joint durability and workability. Collectively, this novel mixture, comprising polymer-modified rubber and mastic asphalt, showcases the potential to enhance the durability of existing asphalt plug joints while ensuring superior constructability and workability.
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Conventional hot mix asphalt overlaying on trench infrastructure typically necessitates extended cooling times for further works and can have adverse effects on buried components, such as electricity cables and hot water pipes. Therefore, this research aims to investigate the use of warm guss mastic asphalt (at an installation temperature of 160 °C) as an overlaying material for mini-trenches, which can reduce the cooling time required for traffic opening and improve the efficiency of the construction process. This research involved two stages: first, lab testing and related research results were used to generate the thermal conductivity and specific heat necessary for simulation work. Second, a finite element model analysis was conducted to evaluate the thermal transmission of the overlaying surface and the buried conduit based on the summer pavement temperature distribution through the Korean Pavement Research Program. Afterward, the field test bed was constructed to verify the simulation. The results indicate that the optimal thickness of the overlaying material and the concrete covering should be designed to ensure thermal durability and meet traffic opening requirements. The overlaying depth of the mini trench using warm mix guss mastic asphalt should be less than 100 mm to meet with the traffic opening time, while the thickness of the concrete covering should be designed to be more than 100 mm to ensure thermal durability. Additionally, the findings suggest that the application of warm guss asphalt could reduce the opening time by 30 min to 1 h and 25 min compared to conventional hot guss asphalt materials. When the pavement surface temperature for the traffic opening is controlled at 50 °C, the asphalt mixture requires at least 2 h to 5 h to meet the cooling criteria for traffic opening, respectively. Overall, this research confirms the potential benefits and optimal use of warm guss mastic asphalt in the construction process of mini-trenches.
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This study compared the characteristics of posterior vitreous detachment (PVD)-related and glaucomatous optic disc hemorrhage (DH). Fundus photographs of eyes with PVD-related DH (PVD group) and glaucomatous DH (glaucoma group) were reviewed. The shape, type, layer, location (clock-hour sector), and DH/disc area (DH/DA) ratio of DH were investigated. In the PVD group, DH presented as a flame (60.9%), splinter (34.8%), and dot or blot (4.3%) shape. However, most of the glaucomatous DH revealed a splinter shape (92.3%), followed by a flame shape (7.7%, p < 0.001). In the PVD group, the most common type of DH was cup margin type (52.2%), whereas, in the glaucoma group it was disc rim type (53.8%, p = 0.003). Both PVD-related and glaucomatous DH were most commonly observed in the 7 o'clock sector. In the PVD group, DH was also found in the 2 and 5 o'clock sectors (p = 0.010). Mean DH/DA ratio in PVD group (0.15 ± 0.19) was greater than in glaucoma group (0.04 ± 0.04, p < 0.001). PVD-related DH showed a higher frequency of flame shape, cup margin type, nasal location, and greater area compared to the glaucomatous DH.
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Glaucoma , Disco Óptico , Doenças do Nervo Óptico , Descolamento do Vítreo , Humanos , Descolamento do Vítreo/complicações , Glaucoma/complicações , Hemorragia Retiniana/etiologiaRESUMO
PURPOSE: To evaluate the dynamic range of retinal nerve fiber layer (RNFL) and optic nerve head (ONH) parameters measured using optical coherence tomography (OCT) in conditions ranging from nonglaucomatous status to advanced glaucoma by longitudinal observation. METHODS: A total of 15 eyes from 12 participants with glaucoma progression from a nonglaucomatous status to advanced glaucoma were included. The RNFL and ONH parameters were compared between the nonglaucomatous and advanced stages within the same eye. The absolute and relative changes in OCT parameters were analyzed. RESULTS: The median highest intraocular pressure was 42.5 mmHg (interquartile range, 37.5 to 54.5 mmHg), and the final mean deviation of the visual field test was -24.68 dB (interquartile range, -23.93 to -31.13 dB). The median relative changes in RNFL thickness were -40.6% in the overall area, and -51.9%, -21.4%, -51.1%, and -41.8% in the superior, nasal, inferior, and temporal quadrants, respectively (all p < 0.05). Relative changes in the rim area, disc area, average cup to disc ratio, vertical cup to disc ratio, and cup volume were -56.64%, 0.59%, 62.10%, 66.0%, and 337.90%, respectively (all p < 0.05, except for disc area with a p-value of 0.753). CONCLUSIONS: The dynamic range of the RNFL thickness ranged from 40.6% to 51.9%, and the dynamic range of the ONH parameters ranged from 56.64% to 337.90%. During the course of glaucoma progression, the cup volume showed the widest dynamic range. However, the disc area did not show significant changes.
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Glaucoma , Disco Óptico , Humanos , Tomografia de Coerência Óptica/métodos , Estudos Longitudinais , Fibras Nervosas , Glaucoma/diagnóstico , Pressão IntraocularRESUMO
We previously constructed a VGG-16 based artificial intelligence (AI) model (image classifier [IC]) to predict the invasion depth in early gastric cancer (EGC) using endoscopic static images. However, images cannot capture the spatio-temporal information available during real-time endoscopy-the AI trained on static images could not estimate invasion depth accurately and reliably. Thus, we constructed a video classifier [VC] using videos for real-time depth prediction in EGC. We built a VC by attaching sequential layers to the last convolutional layer of IC v2, using video clips. We computed the standard deviation (SD) of output probabilities for a video clip and the sensitivities in the manner of frame units to observe consistency. The sensitivity, specificity, and accuracy of IC v2 for static images were 82.5%, 82.9%, and 82.7%, respectively. However, for video clips, the sensitivity, specificity, and accuracy of IC v2 were 33.6%, 85.5%, and 56.6%, respectively. The VC performed better analysis of the videos, with a sensitivity of 82.3%, a specificity of 85.8%, and an accuracy of 83.7%. Furthermore, the mean SD was lower for the VC than IC v2 (0.096 vs. 0.289). The AI model developed utilizing videos can predict invasion depth in EGC more precisely and consistently than image-trained models, and is more appropriate for real-world situations.
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BACKGROUND: Thoracic lymph node (LN) evaluation is essential for the accurate diagnosis of lung cancer and deciding the appropriate course of treatment. Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is considered a standard method for mediastinal nodal staging. This study aims to build a deep convolutional neural network (CNN) for the automatic classification of metastatic malignancies involving thoracic LN, using EBUS-TBNA. METHODS: Patients who underwent EBUS-TBNAs to assess the presence of malignancy in mediastinal LNs during a ten-month period at Severance Hospital, Seoul, Republic of Korea, were included in the study. Corresponding LN ultrasound images, pathology reports, demographic data, and clinical history were collected and analyzed. RESULTS: A total of 2,394 endobronchial ultrasound (EBUS) images of 1,459 benign LNs from 193 patients, and 935 malignant LNs from 177 patients, were collected. We employed the visual geometry group (VGG)-16 network to classify malignant LNs using only traditional cross-entropy for classification loss. The sensitivity, specificity, and accuracy of predicting malignancy were 69.7%, 74.3%, and 72.0%, respectively, and the overall area under the curve (AUC) was 0.782. We applied the new loss function to train the network and, using the modified VGG-16, the AUC improved to a value of 0.8. The sensitivity, specificity, and accuracy improved to 72.7%, 79.0%, and 75.8%, respectively. In addition, the proposed network can process 63 images per second on a single mainstream graphics processing unit (GPU) device, making it suitable for real-time analysis of EBUS images. CONCLUSIONS: Deep CNNs can effectively classify malignant LNs from EBUS images. Selecting LNs that require biopsy using real-time EBUS image analysis with deep learning is expected to shorten the EBUS-TBNA procedure time, increase lung cancer nodal staging accuracy, and improve patient safety.
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Soil salinity is one of the major environmental stresses that restrict the growth and development of tomato (Solanum lycopersicum L.) worldwide. In Arabidopsis, the calcium signaling pathway mediated by calcineurin B-like protein 4 (CBL4) and CBL-interacting protein kinase 24 (CIPK24) plays a critical role in salt stress response. In this study, we identified and isolated two tomato genes similar to the Arabidopsis genes, designated as SlCBL4 and SlCIPK24, respectively. Bimolecular fluorescence complementation (BiFC) and pull-down assays indicated that SlCBL4 can physically interact with SlCIPK24 at the plasma membrane of plant cells in a Ca2+-dependent manner. Overexpression of SlCBL4 or superactive SlCIPK24 mutant (SlCIPK24M) conferred salt tolerance to transgenic tomato (cv. Moneymaker) plants. In particular, the SlCIPK24M-overexpression lines displayed dramatically enhanced tolerance to high salinity. It is notable that the transgenic plants retained higher contents of Na+ and K+ in the roots compared to the wild-type tomato under salt stress. Taken together, our findings clearly suggest that SlCBL4 and SlCIPK24 are functional orthologs of the Arabidopsis counterpart genes, which can be used or engineered to produce salt-tolerant tomato plants.
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We present a novel nanocomposite, a mixture of a CdSe/CdS/ZnS red quantum dot (QD), an Sr(2)SiO(4):Eu green phosphor and silicone resin for a color converting material. The temperature rise and the optical characteristics of the nanocomposite due to the addition of the QD have been investigated in terms of QD content ratio and the mixing components. The experimental results suggested that a small addition of QDs generated a large amount of heat during light conversion at the wavelength of QD emission. Considering the temperature rise in a nanocomposite, we applied 0.2 wt% QDs on an InGaN blue LED chip. As a result, we could achieve a white LED device with a high color rendering index of 83.2, a high luminance of 65.86 lm W(-1) and a moderate temperature increase of 94 °C. The white LED converted by the newly developed QD-phosphor nanocomposite has great potential in future illumination.
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5'-Methylthioadenosine (MTA) and S-adenosylhomocysteine (SAH) are important metabolites in all living organisms. Two similar nucleosidases for hydrolyzing MTA in Arabidopsis thaliana (AtMTAN1 and AtMTAN2) exist, but only AtMTAN2 shows markedly broad substrate specificity for hydrolysis of SAH. To examine the biochemical characteristics of AtMTAN2, it was over-expressed in Escherichia coli and purified to homogeneity. Spectroscopic assays confirm AtMTAN2 catalyzes MTA as well as SAH hydrolysis, compared to AtMTAN1 which only hydrolyzes MTA. In addition, crystal structure of the AtMTAN2 enzyme in complex with, adenine was determined at 2.9A resolution. Finally, a structural comparison of AtMTAN2 performed with previously determined structures of AtMTAN1 and an E. coli homolog provides clues for the substrate specificity of MTA nucleosidases in A. thaliana.
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Proteínas de Arabidopsis/metabolismo , Arabidopsis/enzimologia , Purina-Núcleosídeo Fosforilase/metabolismo , Sequência de Aminoácidos , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/genética , Catálise , Cristalografia por Raios X , Dados de Sequência Molecular , Conformação Proteica , Purina-Núcleosídeo Fosforilase/química , Purina-Núcleosídeo Fosforilase/genéticaRESUMO
Organic light-emitting diodes (OLEDs) with a Ba-doped tris(8-quinolinolato)aluminum(III) (Alq3) layer were fabricated to reduce the barrier height for electron injection and to improve the electron conductivity. In the OLED consisting of glass/ITO/4,4',4"-tris[2-naphthylphenyl-1-phenylamino]triphenylamine (2-TNATA, 30 nm)/4,4'-bis[N-(1-napthyl)-N-phenyl-amino]-biphenyl (NPB, 18 nm)/Alq3 (42 nm)/Ba-doped Alq3 (20 nm, x%: x = 0, 10, 25, and 50)/Al (100 nm), the device with the Alq3 layer doped with 10% Ba showed the highest light out-coupling characteristic. However, as the Ba dopant concentration was increased from 25% to 50%, this device characteristic was largely reduced. The characteristics of these devices were interpreted on the basis of the chemical reaction between Ba and Alq3 and the electron injection property by analyzing the electronic structure of the Ba-doped Alq3 layer. At a low Ba doping of 10%, mainly the Alq3 radical anion species was formed. In addition, the barrier height for electron injection in this layer was decreased to 0.6 eV, when compared to the pristine Alq3 layer. At a high Ba doping of 50%, the Alq3 molecules were severely decomposed. When the Ba dopant concentration was changed, the light-emitting characteristics of the devices were well coincided with the formation mechanism of Alq3 radical anion and Alq3 decomposition species.
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This study examined the mechanism associated with the endothelium-dependent attenuation of vasoconstriction induced by bupivacaine (BPV), with a particular focus on the upstream cellular signaling pathway of endothelial nitric oxide synthase (eNOS) phosphorylation induced by BPV in human umbilical vein endothelial cells (HUVECs). BPV concentration-response curves were investigated in the isolated rat aorta. The effects of Nω-nitro-L-arginine methyl ester (L-NAME), 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ), methylene blue, calmidazolium, the Src kinase inhibitor 4-amino-3-(4-chlorophenyl)-1-(t-butyl)-1H-pyrazolo[3,4-d]pyrimidine, 4-amino-5-(4-chlorophenyl)-7-(t-butyl)pyrazolo[3,4-d]pyrimidine (PP2) and the combination of L-arginine and L-NAME on BPV-induced contraction in endothelium-intact aorta preparations were examined. The effects of BPV alone and in combination with PP2 on the phosphorylation of eNOS (at Ser1177 or Thr495), caveolin-1 and Src kinase were examined in HUVECs. BPV-induced contraction was lower in endothelium-intact aortae than in endothelium-denuded aortae. L-NAME, ODQ, methylene blue and calmidazolium increased BPV-induced contraction in endothelium-intact aortae, whereas PP2 alone and combined treatment with L-arginine and L-NAME inhibited BPV-induced contraction. Low-concentration BPV (30⯵M) induced both stimulatory (Ser1177) and inhibitory (Thr495) phosphorylation of eNOS in HUVECs. However, high-concentration BPV (150⯵M) induced only stimulatory (Ser1177) eNOS phosphorylation. Additionally, phosphorylation of Src kinase, caveolin-1 and inhibitory eNOS (Thr495) induced by low-concentration BPV was inhibited by PP2. These results suggest that contraction induced by low-concentration BPV is attenuated by endothelial nitric oxide release, which is modulated both stimulatory (Ser1177) and inhibitory eNOS phosphorylation (Thr495). BPV-induced phosphorylation of eNOS (Thr495) is indirectly mediated by an upstream cellular signaling pathway involving Src kinase (Tyr416) and caveolin-1 (Tyr14).