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1.
PLoS One ; 18(11): e0293885, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37930987

RESUMEN

Recently, contrastive learning has gained popularity in the field of unsupervised image-to-image (I2I) translation. In a previous study, a query-selected attention (QS-Attn) module, which employed an attention matrix with a probability distribution, was used to maximize the mutual information between the source and translated images. This module selected significant queries using an entropy metric computed from the attention matrix. However, it often selected many queries with equal significance measures, leading to an excessive focus on the background. In this study, we proposed a dual-learning framework with QS-Attn and convolutional block attention module (CBAM) called object-stable dual contrastive learning generative adversarial network (OS-DCLGAN). In this paper, we utilize a CBAM, which learns what and where to emphasize or suppress, thereby refining intermediate features effectively. This CBAM was integrated before the QS-Attn module to capture significant domain information for I2I translation tasks. The proposed framework outperformed recently introduced approaches in various I2I translation tasks, showing its effectiveness and versatility. The code is available at https://github.com/RedPotatoChip/OSUDL.


Asunto(s)
Aprendizaje , Entropía , Probabilidad
2.
ACS Nano ; 17(14): 13938-13947, 2023 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-37410957

RESUMEN

The application of two-dimensional materials has been expanded by introducing the twisted bilayer (TBL) system. However, the landscape of the interlayer interaction in hetero-TBLs has not yet been fully understood, while that in homo-TBLs has been extensively studied, with the dependence on the twist angle between the constituent layers. Here, we present detailed analyses on the interlayer interaction that depends on the twist angle in WSe2/MoSe2 hetero-TBL via Raman and photoluminescence studies combined with first-principles calculation. We observe interlayer vibrational modes, moiré phonons, and the interlayer excitonic states that evolve with the twist angle and identify different regimes with distinct characteristics of such features. Moreover, the interlayer excitons that appear strong in the hetero-TBLs with twist angles near 0° or 60° have different energies and photoluminescence excitation spectra for the two cases, which results from different electronic structures and carrier relaxation dynamics. These results would enable a better understanding of the interlayer interaction in hetero-TBLs.

3.
Mol Med Rep ; 24(5)2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34505634

RESUMEN

Gastritis refers to inflammation caused by injury to the gastric epithelium, which is usually due to excessive alcohol consumption and prolonged use of nonsteroidal anti­inflammatory drugs. Millions of individuals worldwide suffer from this disease. However, the lack of safe and promising treatments makes it urgent to explore and develop leads from natural resources. Therefore, food as medicine may be the best approach for the treatment of these disorders. The present study described the protective effects of food­polydeoxyribonucleotides (f­PDRNs) in a rat model of gastric mucosal injury induced by HCl­EtOH. Administration of f­PDRN was performed with low­PRF002 (26 mg/kg/day), medium­PRF002 (52 mg/kg/day) and high­PRF002 (78 mg/kg/day) on the day of autopsy. The site of damage to the mucous membrane was also analysed. In addition, an increase in gastric juice pH, total acidity of gastric juice and decrease in gastric juice secretion were confirmed, and gastric juice secretion­related factors corresponding to the administration of f­PDRN were analysed. Administration of f­PDRN reduced the mRNA expression of histamine H2 receptor, muscarinic acetylcholine receptor M3, cholecystokinin 2 receptor and H+/K+ ATPase related to gastric acid secretion and downregulation of histamine, myeloperoxidase and cyclic adenosine monophosphate. In addition, it was histologically confirmed that the loss of epithelial cells and the distortion of the mucosa were recovered in the group in which f­PDRN was administered compared to the model group with gastric mucosa damage. In summary, the present study suggested that f­PDRN has therapeutic potential and may have beneficial effects if taken regularly as a food supplement.


Asunto(s)
Mucosa Gástrica/metabolismo , Gastritis/tratamiento farmacológico , Polidesoxirribonucleótidos/farmacología , Consumo de Bebidas Alcohólicas/efectos adversos , Animales , AMP Cíclico/metabolismo , Modelos Animales de Enfermedad , Etanol/efectos adversos , Alimentos , Jugo Gástrico/química , Jugo Gástrico/efectos de los fármacos , Mucosa Gástrica/lesiones , Histamina/metabolismo , Masculino , Polidesoxirribonucleótidos/metabolismo , Ratas , Ratas Sprague-Dawley
4.
Nano Lett ; 21(10): 4305-4313, 2021 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-33970636

RESUMEN

The family of group IV-VI monochalcogenides has an atomically puckered layered structure, and their atomic bond configuration suggests the possibility for the realization of various polymorphs. Here, we report the synthesis of the first hexagonal polymorph from the family of group IV-VI monochalcogenides, which is conventionally orthorhombic. Recently predicted four-atomic-thick hexagonal GeSe, so-called γ-GeSe, is synthesized and clearly identified by complementary structural characterizations, including elemental analysis, electron diffraction, high-resolution transmission electron microscopy imaging, and polarized Raman spectroscopy. The electrical and optical measurements indicate that synthesized γ-GeSe exhibits high electrical conductivity of 3 × 105 S/m, which is comparable to those of other two-dimensional layered semimetallic crystals. Moreover, γ-GeSe can be directly grown on h-BN substrates, demonstrating a bottom-up approach for constructing vertical van der Waals heterostructures incorporating γ-GeSe. The newly identified crystal symmetry of γ-GeSe warrants further studies on various physical properties of γ-GeSe.

5.
Angew Chem Int Ed Engl ; 58(12): 3754-3758, 2019 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-30548756

RESUMEN

Black phosphorus (BP) has received much attention owing to its fascinating properties, such as a high carrier mobility and tunable band gap. However, these advantages have been overshadowed by the fast degradation of BP under ambient conditions. To overcome this obstacle, the exact degradation mechanisms need to be unveiled. Herein, we analyzed two sequential degradation processes and the layer-dependent degradation rates of BP in the dark by scanning Kelvin probe microscopy (SKPM) measurements and theoretical modeling. The layer-dependent degradation was successfully interpreted by considering the oxidation model based on the Marcus-Gerischer theory (MGT). In the dark, the electron transfer rate from BP to oxygen molecules depends on the number of layers as these systems have different carrier concentrations. This work not only provides a deeper understanding of the degradation mechanism itself but also suggest new strategies for the design of stable BP-based electronics.

6.
BMC Med Inform Decis Mak ; 17(Suppl 1): 57, 2017 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-28539116

RESUMEN

BACKGROUND: With the invention of fitness trackers, it has been possible to continuously monitor a user's biometric data such as heart rates, number of footsteps taken, and amount of calories burned. This paper names the time series of these three types of biometric data, the user's "activeness", and investigates the feasibility in modeling and predicting the long-term activeness of the user. METHODS: The dataset used in this study consisted of several months of biometric time-series data gathered by seven users independently. Four recurrent neural network (RNN) architectures-as well as a deep neural network and a simple regression model-were proposed to investigate the performance on predicting the activeness of the user under various length-related hyper-parameter settings. In addition, the learned model was tested to predict the time period when the user's activeness falls below a certain threshold. RESULTS: A preliminary experimental result shows that each type of activeness data exhibited a short-term autocorrelation; and among the three types of data, the consumed calories and the number of footsteps were positively correlated, while the heart rate data showed almost no correlation with neither of them. It is probably due to this characteristic of the dataset that although the RNN models produced the best results on modeling the user's activeness, the difference was marginal; and other baseline models, especially the linear regression model, performed quite admirably as well. Further experimental results show that it is feasible to predict a user's future activeness with precision, for example, a trained RNN model could predict-with the precision of 84%-when the user would be less active within the next hour given the latest 15 min of his activeness data. CONCLUSIONS: This paper defines and investigates the notion of a user's "activeness", and shows that forecasting the long-term activeness of the user is indeed possible. Such information can be utilized by a health-related application to proactively recommend suitable events or services to the user.


Asunto(s)
Biometría , Ejercicio Físico , Monitores de Ejercicio , Redes Neurales de la Computación , Adulto , Algoritmos , Simulación por Computador , Conjuntos de Datos como Asunto , Estudios de Factibilidad , Predicción , Humanos , Factores de Tiempo , Adulto Joven
7.
Stud Health Technol Inform ; 245: 1226, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29295313

RESUMEN

In the rehabilitation treatment for at-home patients, it is not only costly for a patient to hire a professional therapist or personal trainer, but also time consuming for a therapist or trainer to visit all the patients. To improve the situation, we propose the rehabilitation treatment coach robot which helps the patient to do rehabilitation exercises alone. Designed economically with cheap parts, our robot provides multiple functions: rehabilitation program suggestion, rehabilitation posture correction, and emergency detection. A brief plan is presented for data collection and performance evaluation.


Asunto(s)
Terapia por Ejercicio , Robótica , Rehabilitación de Accidente Cerebrovascular , Ejercicio Físico , Humanos , Vehículos a Motor , Rehabilitación
8.
Stud Health Technol Inform ; 245: 1274, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29295359

RESUMEN

We have used deep neural networks (DNNs) to generate clinical opinions from general blood test results. DNNs have overfitting problem in general. We believe the complex structure of DNN and insufficient data to be the major reasons of overfitting in our case. In this paper, we apply dropout and batch normalization to avoid overfitting. Experimental results show the improvement in the performance of the DNNs.


Asunto(s)
Pruebas Hematológicas , Redes Neurales de la Computación , Toma de Decisiones Clínicas , Diagnóstico , Humanos
9.
J Nanosci Nanotechnol ; 15(1): 583-6, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26328407

RESUMEN

The effect of the template of HZSM-5 and its synthesis method on the catalytic conversions of ethanol to aromatic hydrocarbons has been investigated over a 0.8%Zn/0.6%La/HZSM-5 (Si/Al2 = 50) catalyst in a fixed-bed flow reactor under operating conditions of T = 710 K, P = 1 bar, and WHSV = 0.8 hr(-1). Nano- and micro-size HZSM-5 were prepared by hydrothermal and microwave synthesis with different templates: TPAOH, TPABr, and HMDA. Zinc and lanthanum modified HZSM-5 catalysts were prepared by a simple co-impregnation method. It was found that the size of the particles and the crystal structure of HZSM-5 were influenced by the template type and synthesis method. When using the TPAOH template, the nano-sized particles were prepared by microwave synthesis, whereas HZSM-5 prepared from TPABr and HMDA by a hydrothermal method, were composed of cubic shaped nanocrystals inside a micro-sized particle. The effect of the template on the selectivity to aromatics over a La/Zn/HZSM-5 catalyst was shown as follows: HMDA > TPABr > TPAOH.

10.
Biochem Biophys Res Commun ; 463(4): 632-7, 2015 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-26043693

RESUMEN

We investigated whether endogenous neuregulin 1 (NRG1) is released in a soluble form (called sNRG1) and upregulates expression of nicotinic acetylcholine receptor (nAChR) in autonomic major pelvic ganglion (MPG) neurons of adult rats. To elicit the release of sNRG1, either the hypogastric nerve or the pelvic nerve was electrically stimulated. Then, the MPG-conditioned medium (CM) was subjected to western blotting using an antibody directed against the N-terminal ectodomain of NRG1. Both sympathetic and parasympathetic nerve activation elicited the release of sNRG1 from MPG neurons in a frequency-dependent manner. The sNRG1 release was also induced by treatment of MPG neurons with either high KCl or neurotrophic factors. The biological activity of the released sNRG1 was detected by tyrosine phosphorylation (p185) of the ErbB2 receptors in MPG neurons. When MPG neurons were incubated for 6 h in the CM, the protein level of the nAChR α3 subunit and ACh-induced current (IACh) density were significantly increased. The CM-induced changes in IACh was abolished by a selective ErbB2 tyrosine kinase inhibitor. Taken together, these data suggest that NRG1 functions as an endogenous regulator of nAChR expression in adult MPG neurons.


Asunto(s)
Ganglión/fisiopatología , Neurregulina-1/fisiología , Neuronas/fisiología , Pelvis , Receptores Nicotínicos/fisiología , Anciano , Animales , Estimulación Eléctrica , Humanos , Masculino , Ratas , Ratas Sprague-Dawley
11.
J Neurochem ; 124(4): 502-13, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23199222

RESUMEN

We investigated effects of Neuregulin 1 (NRG1) on the expression of nicotinic acetylcholine receptor (nAChR) in major pelvic ganglion (MPG) from adult rat. MPG neurons were found to express transcripts for type I and III NRG1s as well as α and ß-type epidermal growth factor (EGF)-like domains. Of the four ErbB receptor isoforms, ErbB1, ErbB2, and ErbB3 were expressed in MPG neurons. Treating MPG with NRG1ß significantly increased the transcript and protein level of the nAChR α3 and ß4 subunits. Consistent with these molecular data, nicotinic currents (I(ACh) ) were significantly up-regulated in NRG1ß-treated sympathetic and parasympathetic MPG neurons. In contrast, the type III NRG1 and the α form of the NRG1 failed to alter the I(ACh) . Inhibition of the ErbB2 tyrosine kinase completely abolished the effects of NRG1ß on the I(ACh) . Stimulation of the ErbB receptors by NRG1ß activated the phosphatidylinositol-3-kinase (PI3K) and mitogen-activated protein kinase (MAPK). Immunoblot analysis revealed that PI3K-mediated activation of Akt preceded Erk1/2 activation in NRG1ß-treated MPG neurons. Furthermore, specific PI3K inhibitors abrogated the phosphorylation of Erk1/2, while inhibition of MEK did not prevent the phosphorylation of Akt. Taken together, these findings suggest that NRG1 up-regulates nAChR expression via the ErbB2/ErbB3-PI3K-MAPK signaling cascade and may be involved in maintaining the ACh-mediated synaptic transmission in adult autonomic ganglia.


Asunto(s)
Ganglios Autónomos/citología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Neurregulina-1/farmacología , Neuronas/efectos de los fármacos , Receptores Nicotínicos/metabolismo , Regulación hacia Arriba/efectos de los fármacos , Acetilcolina/farmacología , Animales , Cicloheximida/farmacología , Inhibidores Enzimáticos/farmacología , Masculino , Potenciales de la Membrana/efectos de los fármacos , Potenciales de la Membrana/genética , Proteína Quinasa 3 Activada por Mitógenos/genética , Proteína Quinasa 3 Activada por Mitógenos/metabolismo , Técnicas de Placa-Clamp , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Inhibidores de la Síntesis de la Proteína/farmacología , Ratas , Ratas Sprague-Dawley , Receptor ErbB-2/genética , Receptor ErbB-2/metabolismo , Receptor ErbB-3/genética , Receptor ErbB-3/metabolismo , Factores de Tiempo
12.
Neurosci Lett ; 501(1): 55-9, 2011 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-21782342

RESUMEN

Pelvic ganglia (PG) play critical roles in relaying sympathetic and parasympathetic information from the spinal cord to the penile vasculature and, controlling the penile reflex. Animal studies have shown that androgen deprivation by castration causes erectile dysfunction (ED). Until now, however, neural mechanisms underlying castration-induced ED remain unclear. Therefore, we examined whether androgen deprivation down-regulates nicotinic acetylcholine receptors (nAchRs), which mediate fast excitatory synaptic transmission in the PG. Toward this end, neurogenic ED was demonstrated by measuring the intracavernous pressure in castrated rats. Real-time PCR analysis revealed that the transcripts encoding nAchR α3/α5/ß4 subunits were significantly down-regulated in the PG neurons. In addition, down-regulation of the nAchR subunits was reversed by replacement of testosterone. Patch-clamp experiments showed that the nAchR currents were selectively attenuated in the parasympathetic PG neurons innervating the penile vasculature, activation of which elicits penile erection. Taken together, our data suggest that phenotype-specific down-regulation of nAchRs in the PG neurons may contribute to the neurogenic ED in castrated rats.


Asunto(s)
Regulación hacia Abajo , Ganglios Parasimpáticos/metabolismo , Ganglios Simpáticos/metabolismo , Pelvis/inervación , Erección Peniana/fisiología , Receptores Nicotínicos/genética , Animales , Disfunción Eréctil/etiología , Disfunción Eréctil/genética , Disfunción Eréctil/metabolismo , Masculino , Orquiectomía , Ratas , Ratas Sprague-Dawley , Receptores Nicotínicos/metabolismo
13.
Mol Cells ; 28(1): 13-7, 2009 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-19711039

RESUMEN

Basic fibroblast growth factor (bFGF) plays an important role in angiogenesis. However, the underlying mechanisms are not clear. Mg(2+) is the most abundant intracellular divalent cation in the body and plays critical roles in many cell functions. We investigated the effect of bFGF on the intracellular Mg(2+) concentration ([Mg(2+)](i)) in human umbilical vein endothelial cells (HUVECs). bFGF increased [Mg(2+)](i) in a dose-dependent manner, independent of extracellular Mg(2+). This bFGF-induced [Mg(2+)](i) increase was blocked by tyrosine kinase inhibitors (tyrphostin A-23 and genistein), phosphatidylinositol 3-kinase (PI3K) inhibitors (wortmannin and LY294002) and a phospholipase Cgamma (PLCgamma) inhibitor (U73122). In contrast, mitogen-activated protein kinase inhibitors (SB202190 and PD98059) did not affect the bFGF-induced [Mg(2+)](i) increase. These results suggest that bFGF increases the [Mg(2+)](i) from the intracellular Mg(2+) stores through the tyrosine kinase/PI3K/PLCgamma-dependent signaling pathways.


Asunto(s)
Células Endoteliales/efectos de los fármacos , Factor 2 de Crecimiento de Fibroblastos/farmacología , Magnesio/metabolismo , Transducción de Señal/efectos de los fármacos , Androstadienos/farmacología , Línea Celular , Cromonas/farmacología , Relación Dosis-Respuesta a Droga , Células Endoteliales/citología , Células Endoteliales/metabolismo , Estrenos/farmacología , Flavonoides/farmacología , Genisteína/farmacología , Humanos , Imidazoles/farmacología , Espacio Intracelular/efectos de los fármacos , Espacio Intracelular/metabolismo , Microscopía Fluorescente/métodos , Morfolinas/farmacología , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de las Quinasa Fosfoinosítidos-3 , Fosfolipasa C gamma/antagonistas & inhibidores , Fosfolipasa C gamma/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Tirosina Quinasas/antagonistas & inhibidores , Piridinas/farmacología , Pirrolidinonas/farmacología , Tirfostinos/farmacología , Wortmanina
14.
Exp Hematol ; 32(9): 836-42, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15345285

RESUMEN

OBJECTIVE: Acute myeloid leukemia (AML) develops as the consequence of a series of genetic changes in a hematopoietic precursor cell. However, the definitive diagnostic protein biomarkers for AML are still unclear. In our study to identify the biomarkers for an initial diagnosis, detection of relapse, and monitoring the minimal residual disease in AML by a less invasive method, serum proteins reflecting alterations in their proteomes were analyzed. MATERIALS AND METHODS: We compared the two-dimensional electrophoresis patterns of human sera of 12 patients with AML with those of 12 normal subjects. The differentially expressed spots were identified by matrix-assisted laser desorption/ionization time-of-flight and electrospray ionization quadupole time-of-flight mass spectrometries. RESULTS: Eight proteins that expressed differentially in the AML group were found. The expression levels of alpha-2-HS-glycoprotein, complement-associated protein SP-40, 40, RBP4 gene product, lipoprotein C-III, and an unknown protein were downregulated in serum of AML patients, whereas the other three proteins, including immunoglobulin heavy-chain variant, proteosome 26S ATPase subunit 1, and haptoglobin-1 were upregulated. CONCLUSION: These results suggest that these proteins can be used as less invasive diagnostic and monitoring biomarkers of AML if further studies are done.


Asunto(s)
Biomarcadores de Tumor/análisis , Proteínas Sanguíneas/análisis , Leucemia Mieloide Aguda/sangre , Proteoma , Adulto , Femenino , Humanos , Leucemia Mieloide Aguda/diagnóstico , Masculino , Persona de Mediana Edad , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
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