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1.
Artigo em Inglês | MEDLINE | ID: mdl-38656859

RESUMO

Urban safety plays an essential role in the quality of citizens' lives and in the sustainable development of cities. In recent years, researchers have attempted to apply machine learning techniques to identify the role of location-specific attributes in the development of urban safety. However, existing studies have mainly relied on limited images (e.g., map images, single- or four-directional images) of areas based on a relatively large geographical unit and have narrowly focused on severe crime rates, which limits their predictive performance and implications for urban safety. In this work, we propose a novel method that predicts "deviance," which includes formal deviant crimes (e.g., murders) and informal deviant behaviors (e.g., loud parties at night). To do this, we first collect a large-scale geo-tagged dataset consisting of incident report data for seven metropolitan cities, along with corresponding sequential images around incident sites obtained from Google Street View. We then design a convolutional neural network that learns spatio-temporal visual attributes of deviant streets. Experimental results show that our framework is able to reliably recognize real-world deviance in various cities. Furthermore, we analyze which visual attribute is important for deviance identification and severity estimation with respect to social science as well as activated feature maps in the neural network. We have released our dataset and source codes on https://github.com/JinhwiPark/DevianceNet/.

2.
Adv Sci (Weinh) ; 10(32): e2304310, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37691086

RESUMO

Fano resonance, known for its unique asymmetric line shape, has gained significant attention in photonics, particularly in sensing applications. However, it remains difficult to achieve controllable Fano parameters with a simple geometric structure. Here, a novel approach of using a thin-film optical Fano resonator with a porous layer to generate entire spectral shapes from quasi-Lorentzian to Lorentzian to Fano is proposed and experimentally demonstrated. The glancing angle deposition technique is utilized to create a polarization-dependent Fano resonator. By altering the linear polarization between s- and p-polarization, a switchable Fano device between quasi-Lorentz state and negative Fano state is demonstrated. This change in spectral shape is advantageous for detecting materials with a low-refractive index. A bio-particle sensing experiment is conducted that demonstrates an enhanced signal-to-noise ratio and prediction accuracy. Finally, the challenge of optimizing the film-based Fano resonator due to intricate interplay among numerous parameters, including layer thicknesses, porosity, and materials selection, is addressed. The inverse design tool is developed based on a multilayer perceptron model that allows fast computation for all ranges of Fano parameters. The method provides improved accuracy of the mean validation factor (MVF = 0.07, q-q') compared to the conventional exhaustive enumeration method (MVF = 0.37).

3.
Angew Chem Int Ed Engl ; 59(29): 11886-11891, 2020 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-32329937

RESUMO

Oxidative [3+3] cycloadditions offer an efficient route for six-membered-ring formation. This approach has been realized based on an electrochemical oxidative coupling of indoles/enamines with active methylene compounds followed by tandem 6π-electrocyclization leading to the synthesis of dihydropyrano[4,3-b]indoles and 2,3-dihydrofurans. The radical-radical cross-coupling of the radical species generated by anodic oxidation combined with the cathodic generation of the base from O2 allows for mild reaction conditions for the synthesis of structurally complex heterocycles.

4.
Mol Cancer Res ; 7(10): 1663-71, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19808903

RESUMO

We report a Notch signal-induced pathway that leads to transcriptional activation of HIF1-alpha gene. HeLa/rtTAA/TRE-N1-IC cell line capable of doxycycline-induced expression of human Notch1-IC was established. The induction of Notch signaling activates HIF1-alpha and its target gene expression in HeLa/rtTAA/TRE-N1-IC cells. Notch signaling enhanced signal transducers and activators of transcription 3 (STAT3) phosphorylation required for HIF1-alpha expression. SRC kinase was found to be responsible for the enhanced STAT3 phosphorylation in response to Notch signaling. Activation of SRC/STAT3 pathway by Notch signaling was dependent on the expression of Notch effector HES1 transcription factor. The induction of HES1 enhanced STAT3 phosphorylation at Tyr 705 as well as SRC phosphorylation at Tyr 416 in inducible HeLa/rtTAA/TRE-HES1 cells, which express HES1 in response to doxycycline treatment. However, the treatment of Trichostatin A that interferes with HES1 transcriptional regulation did not affect STAT3 phosphorylation, and the expression of dominant negative HES1 failed to interfere with HES1-dependent SRC/STAT3 pathway. These observations have led us to the conclusion that HES1-dependent activation of SRC/STAT3 pathway is independent of HES1 transcription regulation. This study first reports HES1-dependent SRC/STAT3 pathway that provides a functional link between Notch signaling and hypoxia pathway.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Hipóxia Celular/fisiologia , Proteínas de Homeodomínio/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Proteínas Tirosina Quinases/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Receptores Notch/metabolismo , Fator de Transcrição STAT3/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Proteína Tirosina Quinase CSK , Domínio Catalítico/fisiologia , Doxiciclina/farmacologia , Regulação da Expressão Gênica/fisiologia , Células HeLa , Proteínas de Homeodomínio/genética , Humanos , Ácidos Hidroxâmicos/farmacologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Fosforilação , Proteínas Tirosina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Receptores Notch/genética , Elementos Reguladores de Transcrição/fisiologia , Fator de Transcrição STAT3/genética , Transdução de Sinais/fisiologia , Fatores de Transcrição HES-1 , Ativação Transcricional/fisiologia , Regulação para Cima/fisiologia , Quinases da Família src
5.
Cell Signal ; 19(11): 2379-87, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17728103

RESUMO

The signal pathway by which 14-3-3epsilon inhibits cell migration induced by MAPK-activated protein kinase 5 (MK5) was investigated in cultured HeLa cells. Both in vivo and in vitro analyses have revealed that 14-3-3epsilon interacts with MK5. 14-3-3epsilon bound to MK5 inhibits the phosphorylation of HSP27, a known substrate of MK5. Disturbance of actin cytoskeleton organization by 14-3-3epsilon was shown in transfected cells transiently expressing 14-3-3epsilon as well as established cells stably expressing 14-3-3epsilon. Moreover, overexpression of 14-3-3epsilon resulted in the inhibition of cell migration induced by MK5 overexpression or TNFalpha treatment. Our results suggest that 14-3-3epsilon bound to MK5 inhibits cell migration by inhibiting the phosphorylation of HSP27 whose phosphorylation regulates F-actin polymerization, actin cytoskeleton organization and subsequent actinfilament dynamics.


Assuntos
Proteínas 14-3-3/metabolismo , Actinas/química , Actinas/metabolismo , Movimento Celular , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Movimento Celular/efeitos dos fármacos , Citoesqueleto/efeitos dos fármacos , Citoesqueleto/metabolismo , Proteínas de Choque Térmico HSP27 , Células HeLa , Proteínas de Choque Térmico/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Modelos Biológicos , Chaperonas Moleculares , Proteínas de Neoplasias/metabolismo , Fosforilação/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Fator de Necrose Tumoral alfa/farmacologia
6.
J Mol Biol ; 368(2): 388-97, 2007 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-17362989

RESUMO

We propose a biochemical mechanism by which Daxx modulates NF-kappaB transcriptional activity. Both chromatin immunoprecipitation (ChIP) assay and electrophoretic mobility shift assay (EMSA) have confirmed Daxx-mediated repression of transcriptional competence of NF-kappaB in HeLa cells. Overexpression of Daxx repressed the expression of NF-kappaB-regulated genes such as I kappa B alpha and IL8. Co-immunoprecipitation assay revealed the existence of intermolecular association between endogenous Daxx and p65 subunit of NF-kappaB stimulated by TNFalpha. Here, we suggest that Daxx-mediated repression of NF-kappaB transactivation correlates with the inhibition of p65 acetylation by Daxx. Based on the finding that the Daxx binding N-terminal side of p65 includes the major sites of acetylation mediated by p300/CBP, we further propose that the physical interaction between Daxx and p65 provides a functional framework for the inhibition of p65 acetylation by p300/CBP and subsequent repression of NF-kappaB transcriptional activity.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Nucleares/metabolismo , Fator de Transcrição RelA/antagonistas & inibidores , Fator de Transcrição RelA/genética , Ativação Transcricional/genética , Acetilação , Núcleo Celular/metabolismo , Proteínas Correpressoras , Proteína p300 Associada a E1A/metabolismo , Células HeLa , Humanos , Chaperonas Moleculares , Fosforilação , Ligação Proteica , Transporte Proteico , Frações Subcelulares/metabolismo , Fator de Transcrição RelA/metabolismo
7.
Biochem Biophys Res Commun ; 320(3): 760-5, 2004 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-15240113

RESUMO

Daxx-mediated transcriptional repression was modulated by a speckled POZ domain protein SPOP which was first identified as an autoantigen from the serum of a scleroderma patient. This is the first report on the biochemical and functional interactions between Daxx and SPOP. The COOH-terminal region of Daxx interacts with the NH2-terminal region of SPOP. SPOP reversed the transcriptional repression mediated by Daxx which binds with ETS1 transcription factor to repress ETS1-responsive gene expression. Mutagenesis study suggests that the ability of SPOP to self-associate as well as its ability to bind with Daxx was important for the modulation of Daxx-mediated transcriptional repression.


Assuntos
Rim/metabolismo , Metaloproteinase 1 da Matriz/metabolismo , Proteínas Nucleares/metabolismo , Transcrição Gênica/genética , Animais , Células COS , Linhagem Celular , Chlorocebus aethiops , Regulação da Expressão Gênica/fisiologia , Humanos , Metaloproteinase 1 da Matriz/genética , Proteínas Nucleares/genética , Proteínas Repressoras , Relação Estrutura-Atividade
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