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1.
Appl Opt ; 60(26): 8109-8119, 2021 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-34613074

RESUMEN

Hyperspectral anomaly detection aims to classify the anomalous objects in the scene. However, the spatial resolution of the hyperspectral images is relatively low, leading to inaccurate detection of abnormal pixels. Existing methods either ignore the low-resolution problem or leverage super-resolution models to reconstruct the global image to detect abnormal pixels. We claim that reconstructing super-resolution of the global image is unnecessary, while the area where the abnormal target is located should be paid more attention to be reconstructed. In this paper, we propose a super-resolution reconstruction with an attention mechanism for hyperspectral anomaly detection. Our method can automatically extract additional high-frequency information from low-spatial-resolution images and detect abnormal pixels simultaneously. Furthermore, the spatial-channel attention mechanism is adopted to select significant features for reconstructing super-resolution images by assigning different weights to different channels and different spatial-spectral locations. Finally, a regularized join loss function is proposed that balances different tasks by adjusting the relative weight. The experimental results on the public hyperspectral real datasets demonstrate that the proposed method outperforms the state-of-the-art methods.

2.
Appl Opt ; 59(31): 9633-9642, 2020 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-33175802

RESUMEN

Hyperspectral anomaly detection has garnered much research in recent years due to the excellent detection ability of hyperspectral remote sensing in agriculture, forestry, geological surveys, environmental monitoring, and battlefield target detection. The traditional anomaly detection method ignores the non-linearity and complexity of the hyperspectral image (HSI), while making use of the effectiveness of spatial information rarely. Besides, the anomalous pixels and the background are mixed, which causes a higher false alarm rate in the detection result. In this paper, a hyperspectral deep net-based anomaly detector using weight adjustment strategy (WAHyperDNet) is proposed to circumvent the above issues. We leverage three-dimensional convolution instead of the two-dimensional convolution to get a better way of handling high-dimensional data. In this study, the determinative spectrum-spatial features are extracted across the correlation between HSI pixels. Moreover, feature weights in the method are automatically generated based on absolute distance and the spectral similarity angle to describe the differences between the background pixels and the pixels to be tested. Experimental results on five public datasets show that the proposed approach outperforms the state-of-the-art baselines in both effectiveness and efficiency.

3.
FASEB J ; 32(8): 4370-4379, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29543533

RESUMEN

Postprandial insulin desensitization plays a critical role in maintaining whole-body glucose homeostasis by avoiding the excessive absorption of blood glucose; however, the detailed mechanisms that underlie how the major player, skeletal muscle, desensitizes insulin action remain to be elucidated. Herein, we report that early growth response gene-1 ( Egr-1) is activated by insulin in skeletal muscle and provides feedback inhibition that regulates insulin sensitivity after a meal. The inhibition of the transcriptional activity of Egr-1 enhanced the phosphorylation of the insulin receptor (InsR) and Akt, thus increasing glucose uptake in L6 myotubes after insulin stimulation, whereas overexpression of Egr-1 decreased insulin sensitivity. Furthermore, deletion of Egr-1 in the skeletal muscle improved systemic insulin sensitivity and glucose tolerance, which resulted in lower blood glucose levels after refeeding. Mechanistic analysis demonstrated that EGR-1 inhibited InsR phosphorylation and glucose uptake in skeletal muscle by binding to the proximal promoter region of protein tyrosine phosphatase-1B (PTP1B) and directly activating transcription. PTP1B knockdown largely restored insulin sensitivity and enhanced glucose uptake, even under conditions of EGR-1 overexpression. Our results indicate that EGR-1/PTP1B signaling negatively regulates postprandial insulin sensitivity and suggest a potential therapeutic target for the prevention and treatment of excessive glucose absorption.-Wu, J., Tao, W.-W., Chong, D.-Y., Lai, S.-S., Wang, C., Liu, Q., Zhang, T.-Y., Xue, B., Li, C.-J. Early growth response-1 negative feedback regulates skeletal muscle postprandial insulin sensitivity via activating Ptp1b transcription.


Asunto(s)
Proteína 1 de la Respuesta de Crecimiento Precoz/metabolismo , Insulina/metabolismo , Músculo Esquelético/metabolismo , Periodo Posprandial/fisiología , Proteína Tirosina Fosfatasa no Receptora Tipo 1/metabolismo , Animales , Glucemia , Células Cultivadas , Glucosa/metabolismo , Homeostasis/fisiología , Resistencia a la Insulina/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Fibras Musculares Esqueléticas/metabolismo , Fosforilación/fisiología , Ratas , Receptor de Insulina/metabolismo , Transducción de Señal/fisiología , Transcripción Genética/fisiología
4.
Front Public Health ; 11: 1305829, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38274545

RESUMEN

Introduction: The metro has emerged as a major mode of transportation. A significant number of commuters and staff in the metro system are exposed to air pollutants because of its shielded environment, and substantial health damage requires quantitative assessment. Previous studies have focused on comparing the health impacts among different transportation modes, overlooking the specific population characteristics and pollutant distribution in metro systems. Methods: To make improvements, this study implements field monitoring of the metro's air environment utilizing specialized instruments and develops a health damage assessment model. The model quantifies health damage of two main groups (commuters and staff) in metro systems at three different areas (station halls, platforms, and metro cabins) due to particulate matter 10 and benzene series pollution. Conclusion: A case study of Nanjing Metro Line 3 was conducted to demonstrate the applicability of the model. Health damage at different metro stations was analyzed, and the health damage of commuters and staff was assessed and compared. This study contributes to enhancing research on health damage in the metro systems by providing a reference for mitigation measures and guiding health subsidy policies.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Humanos , Contaminantes Atmosféricos/análisis , Material Particulado/análisis , Contaminación del Aire/análisis , Transportes , Monitoreo del Ambiente
5.
Nat Commun ; 14(1): 4495, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37582916

RESUMEN

Reducing greenhouse gas emissions has turned into a pillar of climate change mitigation. Truck platooning is proposed as a strategy to lower emissions from vehicles on roads. However, the potential interactive impacts of this technology on road infrastructure emissions remain unclear. Here, we evaluate the decarbonization effects of truck platooning on the integrated vehicle-road system at a large-scale road network level, spanning 1457 road sections across North America. We show that truck platooning decreases emissions induced by truck operations, but it degrades faster the durability of road infrastructure and leads to a 27.9% rise in road emissions due to more frequent maintenance work. Overall, truck platooning results in a 5.1% emission reduction of the integrated vehicle-road system. In contrast to the benefits of emission reduction, truck platooning leads to additional financial burdens on car users and transportation agencies, calling for the consideration of tradeoffs between emissions and costs and between agencies and users. Our research provides insights into the potential applications of truck platooning to mitigate climate change.

6.
Front Psychol ; 13: 895929, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35783709

RESUMEN

The construction industry is one of the most dangerous industries with grave situation owing to high accident rate and mortality rate, which accompanied with a series of security management issues that need to be tackled urgently. The unsafe behavior of construction workers is a critical reason for the high incidence of safety accidents. Affective Events Theory suggests that individual emotional states interfere with individual decisions and behaviors, which means the individual emotional states can significantly influence construction workers' unsafe behaviors. As the complexity of the construction site environment and the lack of attention to construction workers' emotions by managers, serious potential emotional problems were planted, resulting in the inability of construction workers to effectively recognize safety hazards, thus leading to safety accidents. Consequently, the study designs a behavioral experiment with E-prime software based on social cognitive neuroscience theories. Forty construction workers' galvanic skin response signals were collected by a wearable device (HKR-11C+), and the galvanic skin response data were classified into different emotional states with support vector machine (SVM) algorithm. Variance analysis, correlation analysis and regression analysis were used to analyze the influence of emotional states on construction workers' recognition ability of safety hazards. The research findings indicate that the SVM algorithm could effectively classify galvanic skin response data. The construct ion workers' the reaction time to safety hazards and emotional valence were negatively correlated, while the accuracy of safety hazards recognition and the perception level of safety hazard separately had an inverted "U" type relationship with emotional valence. For construction workers with more than 20 years of working experience, work experience could effectively reduce the influence of emotional fluctuations on the accuracy of safety hazards identification. This study contributes to the application of physiological measurement techniques in construction safety management and shed a light on improving the theoretical system of safety management.

7.
J Mol Cell Biol ; 13(6): 445-454, 2021 09 11.
Artículo en Inglés | MEDLINE | ID: mdl-33760044

RESUMEN

During embryonic heart development, the progenitor cells in the epicardium would migrate and differentiate into noncardiomyocytes in myocardium and affect the integrity of ventricular wall, but the underlying mechanism has not been well studied. We have found that myocardium geranylgeranyl diphosphate synthase (Ggpps), a metabolic enzyme for cholesterol biosynthesis, is critical for cardiac cytoarchitecture remodelling during heart development. Here, we further reveal that epicardial Ggpps could also regulate ventricular wall architecture integrity. Epicardium-specific deletion of Ggpps before embryonic day 10.5 (E10.5) is embryonic lethal, whereas after E13.5 is survival but with defects in the epicardium and ventricular wall structure. Ggpps deficiency in the epicardium enhances the proliferation of epicardial cells and disrupts cell‒cell contact, which makes epicardial cells easier to invade into ventricular wall. Thus, the fibroblast proliferation and coronary formation in myocardium were found enhanced that might disturb the coronary vasculature remodelling and ventricular wall integrity. These processes might be associated with the activation of YAP signalling, whose nuclear distribution is blocked by Ggpps deletion. In conclusion, our findings reveal a potential link between the cholesterol metabolism and heart epicardium and myocardium development in mammals, which might provide a new view of the cause for congenital heart diseases and potential therapeutic target in pathological cardiac conditions.


Asunto(s)
Colesterol/metabolismo , Farnesiltransferasa/metabolismo , Pericardio/metabolismo , Animales , Células Cultivadas , Desarrollo Embrionario/fisiología , Femenino , Corazón/fisiología , Masculino , Ratones , Ratones Noqueados , Miocardio/metabolismo , Embarazo , Transducción de Señal/fisiología
8.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(8): 2049-52, 2010 Aug.
Artículo en Zh | MEDLINE | ID: mdl-20939304

RESUMEN

The electronic spectra and energy levels of Ho3+ in Cs2NaYF6 were studied on basis of rare earth (RE) spectrum, quantum mechanics and crystal field theory. Detailed analysis on electronic absorption spectra at temperatures down to 10 K in the range of 4600-24,000 cm(-1) was carried out. The transitions, with zero phonon lines (ZPL) and abundant vibronic sidebands, from ground states to different excited states such as 5I(J); (J = 7, 6, 5, 4), 5F(S) (S = 5, 4, 3), 5G(P) (P = 6, 5) and (3)K8 were clearly observed. All the transitions have been assigned and 50 experimental crystal field levels have been obtained. The dataset has been investigated by standard f-shell program, which gave out the calculated energy levels and the corresponding empirical Hamiltonian parameters. The comparison of the energy levels and Hamiltonian parameters was made with that of Cs2NaYCl6 : Ho3+ as well.

9.
Bioorg Med Chem ; 17(22): 7755-68, 2009 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-19836248

RESUMEN

Cysteine-dependant aspartyl protease (caspase) activation has been implicated as a part of the signal transduction pathway leading to apoptosis. It has been postulated that caspase-3 inhibition could attenuate cell damage after an ischemic event and thereby providing for a novel neuroprotective treatment for stroke. As part of a program to develop a small molecule inhibitor of caspase-3, a novel series of 3,4-dihydropyrimido(1,2-a)indol-10(2H)-ones (pyrimidoindolones) was identified. The synthesis, biological evaluation and structure-activity relationships of the pyrimidoindolones are described.


Asunto(s)
Inhibidores de Caspasas , Inhibidores de Proteasas/química , Inhibidores de Proteasas/farmacología , Pirimidinonas/química , Pirimidinonas/farmacología , Apoptosis/efectos de los fármacos , Caspasa 3/metabolismo , Línea Celular , Escherichia coli , Inhibidores de Proteasas/síntesis química , Pirimidinonas/síntesis química , Accidente Cerebrovascular/metabolismo , Accidente Cerebrovascular/patología , Relación Estructura-Actividad
10.
Environ Pollut ; 242(Pt B): 1633-1641, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30082153

RESUMEN

The bioaccessibility of organic pollutants is a key factor in human health risk assessments. We developed a novel in vitro method for determining the mass fraction of bioaccessible atmospheric polycyclic aromatic hydrocarbons (PAHs) using an air-washing device containing simulated human lung fluid. The experimental parameters were optimized based on the deposition fractions (DFs) of PAHs in human lung fluids. The DFs were measured for PAHs based on the mass of compounds in the mainstream and exhaled cigarette smoke. The mass fractions of bioaccessible PAHs were measured by passing the mainstream cigarette smoke through the air-washing device, and they were calculated via a simple mass balance equation based on the PAHs in the fluid and mainstream cigarette smoke. The DFs of individual PAHs ranged from 20.5% to 78.1%, and the bioaccessible mass fractions varied between 45.5% and 99.8%. The octanol-water partition coefficients (KOW) significantly influenced both the DFs and bioaccessible mass fractions of PAHs, and the optimized in vitro method could be used to estimate the bioavailable atmospheric PAHs. This in vitro method can potentially be used to measure the mass fraction of bioaccessible atmospheric PAHs and to assess the health risk related to human exposure to airborne PAHs.


Asunto(s)
Contaminantes Atmosféricos/análisis , Pulmón/metabolismo , Hidrocarburos Policíclicos Aromáticos/análisis , Humanos , Medición de Riesgo , Humo , Nicotiana
11.
J Med Chem ; 53(10): 4066-84, 2010 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-20443629

RESUMEN

As part of an effort to identify 5-HT(1A) antagonists that did not possess typical arylalkylamine or keto/amido-alkyl aryl piperazine scaffolds, prototype compound 10a was identified from earlier work in a combined 5-HT(1A) antagonist/SSRI program. This quinolyl-piperazinyl piperidine analogue displayed potent, selective 5-HT(1A) antagonism but suffered from poor oxidative metabolic stability, resulting in low exposure following oral administration. SAR studies, driven primarily by in vitro liver microsomal stability assessment, identified compound 10b, which displayed improved oral bioavailability and lower intrinsic clearance. Further changes to the scaffold (e.g., 10r) resulted in a loss in potency. Compound 10b displayed cognitive enhancing effects in a number of animal models of learning and memory, enhanced the antidepressant-like effects of the SSRI fluoxetine, and reversed the sexual dysfunction induced by chronic fluoxetine treatment.


Asunto(s)
Piperazinas/síntesis química , Piperidinas/síntesis química , Quinolinas/síntesis química , Antagonistas del Receptor de Serotonina 5-HT1 , Acetilcolina/metabolismo , Administración Oral , Precursor de Proteína beta-Amiloide/genética , Animales , Antidepresivos/síntesis química , Antidepresivos/química , Antidepresivos/farmacología , Disponibilidad Biológica , Células CHO , Corteza Cerebral/metabolismo , Cognición/efectos de los fármacos , Cricetinae , Cricetulus , Fluoxetina/farmacología , Hipocampo/metabolismo , Técnicas In Vitro , Aprendizaje por Laberinto/efectos de los fármacos , Memoria/efectos de los fármacos , Ratones , Ratones Transgénicos , Microsomas Hepáticos/metabolismo , Nootrópicos/síntesis química , Nootrópicos/química , Nootrópicos/farmacología , Erección Peniana/efectos de los fármacos , Piperazinas/química , Piperazinas/farmacología , Piperidinas/química , Piperidinas/farmacología , Quinolinas/química , Quinolinas/farmacología , Ratas , Serotonina/metabolismo , Relación Estructura-Actividad
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