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1.
Small ; 20(8): e2306997, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37823688

RESUMEN

MXenes have demonstrated significant potential in electrochemical energy storage, particularly in supercapacitors, owing to their exceptional properties. The surface terminal groups of MXene play a pivotal role in pseudocapacitive mechanism. Considering the hindered electrolyte ion transport caused by -F terminal groups and the limited ion binding sites associated with -O terminal groups, this study proposes a novel strategy of replacing -F with -N terminal groups. The modulated MXene-N electrode, featuring a substantial number of -N terminal groups, demonstrates an exceptionally high gravimetric capacitance of 566 F g-1 (at a scan rate of 2 mV s-1 ) or 588 F g-1 (at a discharge rate of 1 A g-1 ) in 1 м H2 SO4 electrolyte, and the potential window is significantly increased. Furthermore, subsequent spectra analysis and density functional theory calculations are employed to investigate the mechanism associated with -N terminal groups. This work exemplifies the significance of terminal modulation in the context of electrochemical energy storage.

2.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 40(2): 249-256, 2023 Apr 25.
Artículo en Zh | MEDLINE | ID: mdl-37139755

RESUMEN

Hypertension is the primary disease that endangers human health. A convenient and accurate blood pressure measurement method can help to prevent the hypertension. This paper proposed a continuous blood pressure measurement method based on facial video signal. Firstly, color distortion filtering and independent component analysis were used to extract the video pulse wave of the region of interest in the facial video signal, and the multi-dimensional feature extraction of the pulse wave was preformed based on the time-frequency domain and physiological principles; Secondly, an integrated feature selection method was designed to extract the universal optimal feature subset; After that, we compared the single person blood pressure measurement models established by Elman neural network based on particle swarm optimization, support vector machine (SVM) and deep belief network; Finally, we used SVM algorithm to build a general blood pressure prediction model, which was compared and evaluated with the real blood pressure value. The experimental results showed that the blood pressure measurement results based on facial video were in good agreement with the standard blood pressure values. Comparing the estimated blood pressure from the video with standard blood pressure value, the mean absolute error (MAE) of systolic blood pressure was 4.9 mm Hg with a standard deviation (STD) of 5.9 mm Hg, and the MAE of diastolic blood pressure was 4.6 mm Hg with a STD of 5.0 mm Hg, which met the AAMI standards. The non-contact blood pressure measurement method based on video stream proposed in this paper can be used for blood pressure measurement.


Asunto(s)
Determinación de la Presión Sanguínea , Hipertensión , Humanos , Algoritmos , Presión Sanguínea/fisiología , Determinación de la Presión Sanguínea/métodos , Hipertensión/diagnóstico
3.
Small ; 18(4): e2105696, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34837326

RESUMEN

The oxygen evolution reaction (OER) plays a key role in many electrochemical energy conversion systems, but it is a kinetically sluggish reaction and requires a large overpotential to deliver appreciable current, especially for the non-noble metal electrocatalysts. In this study, the authors report a surface phase engineering strategy to improve the OER performance of transition metal nitrides (TMNs). The iron-nickel nitrides/alloy nanospheres (FeNi3 -N) wrapped in carbon are synthesized, and the optimized FeNi3 -N catalyst displays dual-phase nitrides on the surface induced by atom migration phenomenon, resulting from the different migration rates of metal atoms during the nitridation process. It shows excellent OER performance in alkaline media with an overpotential of 222 mV at 10 mA cm-2 , a small Tafel slope of 41.53 mV dec-1 , and long-term durability under high current density (>0.5 A cm-2 ) for at least 36 h. Density functional theory (DFT) calculations further reveal that the dual-phase nitrides are favorable to decrease the energy barrier, modulate the d-band center to balance the absorption and desorption of the intermediates, and thus promote the OER electrochemical performance. This strategy may shed light on designing OER and other catalysts based on surface phase engineering.

4.
J Perianesth Nurs ; 37(1): 53-62.e1, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34756625

RESUMEN

PURPOSE: Identifying factors that place patients at high risk for developing postoperative delirium is an important first step to reduce incidence. Frailty is associated with poor postoperative outcomes. This meta-analysis aims to determine the association between preoperative frailty and postoperative delirium. DESIGN: This is a systematic review and meta-analysis. METHODS: We used PubMed, Scopus, Embase, CINAHL, Cochrane, and Web of Science as databases for the search up to April 23, 2020. We included cohort studies that assessed postoperative delirium as the outcome and described the prevalence of delirium among participants during the postoperative period. Odds ratio and 95% confidence interval were calculated to examine the association. FINDINGS: Twenty cohort studies met our inclusion criteria, which included a total of 4,568 patients. We found that preoperative frailty was significantly associated with an increased risk of postoperative delirium (crude odds ratio: 3.28; 95% confidence interval: 2.51 to 4.28; I2 = 46.7%) (adjusted odds ratio: 2.45; 95% confidence interval: 1.58 to 3.81; I2 = 88.6%). CONCLUSIONS: This meta-analysis showed that preoperative frailty is an independent risk factor for postoperative delirium. In patients undergoing cardiovascular surgery, there is a lower association between frailty and postoperative delirium. In patients with other types of surgery, preoperative frailty is closely related to postoperative delirium.


Asunto(s)
Delirio , Fragilidad , Estudios de Cohortes , Delirio/epidemiología , Delirio/etiología , Fragilidad/complicaciones , Humanos , Incidencia , Complicaciones Posoperatorias/epidemiología , Factores de Riesgo
5.
J Integr Neurosci ; 20(4): 977-984, 2021 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-34997720

RESUMEN

Major depression disorder is one of the diseases with the highest rate of disability and morbidity and is associated with numerous structural and functional differences in neural systems. However, it is difficult to analyze digital medical imaging data without computational intervention. A voxel-wise densely connected convolutional neural network, Three-dimensional Densenet (3D-DenseNet), is proposed to mine the feature differences. In addition, a novel transfer learning method, called Alzheimer's Disease Neuroimaging Initiative Transfer (ADNI-Transfer), is designed and combined with the proposed 3D-DenseNet. The experimental results on a database that contains 174 subjects, including 99 patients with major depression disorder and 75 healthy controls, show that large changes in brain structures between major depressive disorder patients and healthy controls mainly are located in the regions including superior frontal gyrus, dorsolateral, middle temporal gyrus, middle frontal gyrus, postcentral gyrus, inferior temporal gyrus. In addition, the proposed deep learning network can better extract different features of brain structures between major depressive disorder patients and healthy controls and achieve excellent classification results of major depressive disorder. At the same time, the designed transfer learning method can further improve classification performance. These results verify that our proposed method is feasible and valid for diagnosing and analyzing major depression disorder.


Asunto(s)
Corteza Cerebral/diagnóstico por imagen , Aprendizaje Profundo , Trastorno Depresivo Mayor/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Neuroimagen/métodos , Adulto , Estudios de Factibilidad , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Procesamiento de Imagen Asistido por Computador/normas , Imagen por Resonancia Magnética/normas , Masculino , Persona de Mediana Edad , Neuroimagen/normas , Reproducibilidad de los Resultados , Adulto Joven
6.
Inorg Chem ; 58(15): 10295-10303, 2019 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-31329423

RESUMEN

To construct desired metal-organic framework (MOF) sensors, the predesigned functionalized ligands 2,5-bis(2',5'-dicarboxylphenyl)pyridine (L-N) and 2,5-bis(2',5'-dicarboxylphenyl)difluorobenzene (L-F) with pyridine- and fluorine-decorated tetracarboxylic acids were used, and two stable terbium-organic frameworks, H3O[(Tb(L-N)(H2O)2]·2H2O (Tb-N) and [Tb3(L-F)2(HCOO)(H2O)4]·6H2O (Tb-F), have been synthesized. The structures of Tb-N and Tb-F contain 1D open channels, which are functionalized by pyridine N or F atoms, respectively. Both of them show intense fluorescence in water and exhibit excellent selectivity and sensitivity to Fe3+ ions. The effects of different functional group sites on the stability and fluorescence sensing performance of MOFs have also been studied. In addition, a gas adsorption study demonstrates that Tb-N is capable of adsorbing C2H2 over CH4 selectively.

7.
Inorg Chem ; 57(15): 9385-9392, 2018 Aug 06.
Artículo en Inglés | MEDLINE | ID: mdl-30024155

RESUMEN

Transition-metal (TM) phosphides attract increasing attention with applications for energy conversion and storage, due to their outstanding physical, chemical, and electronic properties. The 3d transition metal tetraphosphides (TMP4, TM = V, Cr, Mn, and Fe) possess multiple allotropies and rich electronic properties. Here, we perform the investigations of the structural, electronic, and elastic properties for 3d-TMP4 (TM = V, Cr, Mn, and Fe) using density functional theory (DFT) calculations. These compounds are featured with alternating buckled phosphorus sheets with ten-numbered phosphorus rings and varied transition-metal layers. Hybrid DFT calculations reveal that TMP4 compounds exhibit a wide range of electrical properties, ranging from metallic behavior for VP4 to semiconducting behavior for CrP4 with the narrow direct band gap of 0.63 eV to enlarged semiconducting MnP4 and FeP4 with band gap of 1.6-2.1 eV. The bonding analysis indicates that P-P and TM-P covalent interactions dominate in the phosphorus sheets and TMP6 octahedrons, which are responsible for the structural and electronic diversity.

8.
J Biol Chem ; 290(51): 30607-15, 2015 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-26504089

RESUMEN

Dysregulation of hepatic gluconeogenesis contributes to the pathogenesis of diabetes, yet the detailed molecular mechanisms remain to be fully elucidated. Here we show that FOXP1, a transcriptional repressor, plays a key role in the regulation of systemic glucose homeostasis. Hepatic expression levels of FOXP1 are decreased in diabetic mice. Modest hepatic overexpression of FOXP1 in mice inhibited the expression of gluconeogenic genes, such as peroxisome proliferators-activated receptor γ coactivator-1α (PGC-1α), phosphoenolpyruvate carboxykinase (PEPCK), and glucose-6-phosphatase (G6PC), leading to a decrease in hepatic glucose production and fasting blood glucose levels in normal mice and different mouse models of diabetes, including db/db diabetic and high-fat diet-induced obese mice. FOXP1 physically interacted with FOXO1 in vivo and competed with FOXO1 for binding to the insulin response element in the promoter region of gluconeogenic genes, thereby interfering expression of these genes. These results identify a previously unrecognized role for FOXP1 in the transcriptional control of hepatic glucose homeostasis.


Asunto(s)
Factores de Transcripción Forkhead/metabolismo , Gluconeogénesis , Glucosa/metabolismo , Homeostasis , Hígado/metabolismo , Proteínas Represoras/metabolismo , Animales , Diabetes Mellitus/genética , Diabetes Mellitus/metabolismo , Grasas de la Dieta/efectos adversos , Grasas de la Dieta/farmacología , Factores de Transcripción Forkhead/genética , Glucosa/genética , Masculino , Ratones , Ratones Obesos , Obesidad/inducido químicamente , Obesidad/genética , Obesidad/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma , Fosfoenolpiruvato Carboxiquinasa (GTP) , Proteínas Represoras/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
9.
Arthritis Rheum ; 65(10): 2573-82, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23817999

RESUMEN

OBJECTIVE: Germinal center kinase-like kinase (GLK; also called MAPKKKK-3) activates protein kinase Cθ (PKCθ) during T cell activation and controls autoimmunity in lupus patients. Intracellular kinases are involved in the pathogenesis of rheumatoid arthritis (RA). We undertook this study to determine the role of GLK in RA. METHODS: The severity of collagen-induced arthritis (CIA) was studied in GLK-deficient mice. Expression levels of GLK from RA patients were determined by Western blotting, flow cytometry, real-time polymerase chain reaction, and immunohistochemical staining. Localization of GLK in T cells was identified by confocal microscopy. RA disease activity was assessed using the Disease Activity Score in 28 joints. RESULTS: GLK-deficient mice displayed impaired CIA development and decreased inflammatory cytokine levels. Local T cell infiltration and collagen restimulation responses were impaired by GLK deficiency. RA patients showed significantly higher GLK protein and messenger RNA levels in peripheral blood T cells than did healthy controls. GLK-overexpressing T cells in synovial fluid and synovial tissue samples from RA patients were increased compared with those from osteoarthritis patients. Confocal microscopy and flow cytometry showed that GLK colocalized and coexisted with phosphorylated PKCθ in T cells from RA patients. Frequencies of GLK-expressing T cells were significantly correlated with RA disease activity. CONCLUSION: GLK overexpression in T cells contributes to the pathogenesis of RA, indicating that GLK is a novel biomarker for autoimmune disease severity and a potential therapeutic target for RA.


Asunto(s)
Artritis Experimental/diagnóstico , Artritis Experimental/metabolismo , Artritis Reumatoide/diagnóstico , Artritis Reumatoide/metabolismo , Proteínas Quinasas/metabolismo , Linfocitos T/metabolismo , Adulto , Anciano , Animales , Artritis Experimental/patología , Artritis Reumatoide/patología , Biomarcadores/metabolismo , Complejo CD3/metabolismo , Estudios de Casos y Controles , Diagnóstico Diferencial , Modelos Animales de Enfermedad , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Persona de Mediana Edad , Osteoartritis/diagnóstico , Osteoartritis/metabolismo , Osteoartritis/patología , Proteínas Quinasas/deficiencia , Proteínas Quinasas/genética , Índice de Severidad de la Enfermedad , Líquido Sinovial/metabolismo , Membrana Sinovial/metabolismo , Membrana Sinovial/patología , Linfocitos T/patología
10.
Adv Sci (Weinh) ; 11(17): e2302988, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38430538

RESUMEN

Peripheral nerve injury (PNI) remains a challenging area in regenerative medicine. Nerve guide conduit (NGC) transplantation is a common treatment for PNI, but the prognosis of NGC treatment is unsatisfactory due to 1) neuromechanical unmatching and 2) the intra-conduit inflammatory microenvironment (IME) resulting from Schwann cell pyroptosis and inflammatory-polarized macrophages. A neuromechanically matched NGC composed of regenerated silk fibroin (RSF) loaded with poly(3,4-ethylenedioxythiophene): poly(styrene sulfonate) (P:P) and dimethyl fumarate (DMF) are designed, which exhibits a matched elastic modulus (25.1 ± 3.5 MPa) for the peripheral nerve and the highest 80% elongation at break, better than most protein-based conduits. Moreover, the NGC can gradually regulate the intra-conduit IME by releasing DMF and monitoring sciatic nerve movements via piezoresistive sensing. The combination of NGC and electrical stimulation modulates the IME to support PNI regeneration by synergistically inhibiting Schwann cell pyroptosis and reducing inflammatory factor release, shifting macrophage polarization from the inflammatory M1 phenotype to the tissue regenerative M2 phenotype and resulting in functional recovery of neurons. In a rat sciatic nerve crush model, NGC promoted remyelination and functional and structural regeneration. Generally, the DMF/RSF/P:P conduit provides a new potential therapeutic approach to promote nerve repair in future clinical treatments.


Asunto(s)
Fibroínas , Regeneración Nerviosa , Traumatismos de los Nervios Periféricos , Animales , Regeneración Nerviosa/efectos de los fármacos , Regeneración Nerviosa/fisiología , Ratas , Traumatismos de los Nervios Periféricos/terapia , Fibroínas/química , Fibroínas/farmacología , Modelos Animales de Enfermedad , Ratas Sprague-Dawley , Células de Schwann/metabolismo , Regeneración Tisular Dirigida/métodos , Inflamación , Andamios del Tejido/química , Nervio Ciático/lesiones
11.
J Hepatol ; 58(4): 763-70, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23183531

RESUMEN

BACKGROUND & AIMS: Missense mutations in human Krüppel-like factor 11 (KLF11) lead to the development of diabetes, as a result of impaired insulin synthesis in the pancreas. However, the role of KLF11 in peripheral tissues is largely unknown. The aim of this study is to evaluate the role of KLF11 in the regulation of hepatic lipid homeostasis using different mouse models. METHODS: Adenoviruses expressing KLF11 (Ad-KLF11) or KLF11-specific shRNA (Ad-shKLF11) were injected into db/db diabetic, high-fat diet-induced obese (DIO), or normal C57BL/6J mice. Histological analysis of the fatty liver phenotype and biochemical analysis of hepatic and serum TG levels in these mice were performed. The molecular mechanism by which KLF11 regulates lipid metabolism in primary hepatocytes and mouse livers was explored. RESULTS: The expression of the transcription factor KLF11 gene is dysregulated in the livers of db/db and DIO mice. Adenovirus-mediated overexpression of KLF11 in the livers of db/db and DIO mice activates the PPARα signaling pathway, subsequently markedly improving the fatty liver phenotype. Conversely, knockdown of KLF11, by adenovirus (Ad-shKLF11) in livers of wild type C57BL/6J and db/m mice, increases hepatic triglyceride (TG) levels, owing to decreased fatty acid oxidation. Finally, the treatment of diabetic mice with Ad-shPPARα abolishes KLF11 stimulatory effects on the expression of genes involved in fatty acid oxidation and inhibitory effects on hepatic TG content. In contrast, PPARα rescue restores the increased hepatic TG levels in Ad-shKLF11-infected db/m mice to normal levels. CONCLUSIONS: KLF11 is an important regulator of hepatic lipid metabolism.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Metabolismo de los Lípidos , Hígado/metabolismo , Factores de Transcripción/metabolismo , Animales , Proteínas Reguladoras de la Apoptosis , Proteínas de Unión al ADN/antagonistas & inhibidores , Proteínas de Unión al ADN/genética , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Regulación de la Expresión Génica , Técnicas de Silenciamiento del Gen , Hepatocitos/metabolismo , Humanos , Metabolismo de los Lípidos/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes , Ratones Transgénicos , Estado Nutricional , Obesidad/genética , Obesidad/metabolismo , PPAR alfa/metabolismo , ARN Interferente Pequeño/genética , Proteínas Represoras , Transducción de Señal , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/genética , Triglicéridos/metabolismo
12.
J Nat Prod ; 76(2): 216-22, 2013 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-23394318

RESUMEN

Ten new abietane diterpenoids, aquilarabietic acids A-J (1-10), and a new podocarpane diterpenoid, aquilarabietic acid K (11), were isolated from the petroleum ether and ethanol extracts of Chinese eaglewood. Among them, 3, 9, and 10 are artifacts. Their structures were established on the basis of data from extensive spectroscopic and X-ray diffraction analyses. Bioassay results indicated that 1 at 10 µM demonstrated remarkable antidepressant activity in vitro by inhibiting norepinephrine reuptake in rat brain synaptosomes by 81.4% and with an IC(50) value of 9.1 × 10(-7) M.


Asunto(s)
Abietanos/aislamiento & purificación , Abietanos/farmacología , Antidepresivos/aislamiento & purificación , Antidepresivos/farmacología , Medicamentos Herbarios Chinos/aislamiento & purificación , Medicamentos Herbarios Chinos/farmacología , Thymelaeaceae/química , Abietanos/química , Animales , Antidepresivos/química , Encéfalo/efectos de los fármacos , Medicamentos Herbarios Chinos/química , Masculino , Estructura Molecular , Norepinefrina/antagonistas & inhibidores , Resonancia Magnética Nuclear Biomolecular , Ratas , Sinaptosomas/efectos de los fármacos
13.
Planta Med ; 79(12): 1063-7, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23818269

RESUMEN

Three new unusual 23-spirocholestane derivatives, ypsilanogenin (1), ypsilanogenin 3-O-ß-D-glucopyranoside (2), and 4'-acetylypsilanogenin 3-O-ß-D-glucopyranoside (3), were isolated from the whole plants of Ypsilandra thibetica. The structures of compounds 1-3 were deduced by spectroscopic and chemical methods, and the structure of 1 was further confirmed by a single-crystal diffraction analysis. All isolates were evaluated for their inhibitory activities against HIV-1.


Asunto(s)
Fármacos Anti-VIH/farmacología , Glicósidos/farmacología , Liliaceae/química , Fármacos Anti-VIH/química , Fármacos Anti-VIH/aislamiento & purificación , Colestanos/química , Colestanos/aislamiento & purificación , Colestanos/farmacología , Cristalografía por Rayos X , Glicósidos/química , Glicósidos/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Estructura Molecular , Plantas Medicinales , Saponinas/química , Saponinas/aislamiento & purificación , Saponinas/farmacología , Compuestos de Espiro/química , Compuestos de Espiro/aislamiento & purificación , Compuestos de Espiro/farmacología
14.
J Asian Nat Prod Res ; 15(10): 1130-8, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23869424

RESUMEN

A new limonoid compound, named evorubodinin (1), was isolated from the dried and nearly ripe fruits of Euodia rutaecarpa (Juss.) Benth. var. bodinieri (Dode) Huang (family Rutaceae), together with two known limonoid compounds, limonin (2) and evolimorutanin (3). The chemical structure of 1 was elucidated by spectroscopic method and single-crystal X-ray diffraction. The inhibitory effects of the isolated compounds 1-3 and the structurally related compounds evodol (4), shihulimonin A1 (5), evodirutaenin (6), 12α-hydroxyrutaevin (7), and rutaevin (8) on nitric oxide (NO) production in lipopolysaccharide-activated RAW264.7 macrophages were also assayed. All compounds 1-8 showed the inhibitory activity, in which both 7 and 8 with the uncommon 5ß-H configuration more efficiently inhibited NO production. The results provided valuable information for further investigation of compounds 1-8 as anti-inflammatory agents or lead compounds.


Asunto(s)
Evodia/química , Limoninas/aislamiento & purificación , Limoninas/farmacología , Lipopolisacáridos/farmacología , Macrófagos/efectos de los fármacos , Óxido Nítrico/antagonistas & inhibidores , Animales , Antiinflamatorios , Frutas/química , Limoninas/química , Ratones , Estructura Molecular , Óxido Nítrico/biosíntesis , Triterpenos/química
15.
World J Clin Cases ; 11(32): 7905-7910, 2023 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-38073693

RESUMEN

BACKGROUND: Gastric duplication cysts are very rare disease that are mainly diagnosed by endoscopic ultrasonographic fine-needle aspiration biopsy. In the past, this disease was usually treated with traditional surgery and rarely with minimally invasive endoscopic surgery. However, minimally invasive endoscopic therapy has many advantages, such as no skin wound, organ preservation, postoperative pain reduction, early food intake, fewer postoperative complications, and shorter post-procedure hospitalization. CASE SUMMARY: We report a case of endoscopic ultrasonography-guided fine-needle aspiration (EUS-FNA) combined with lauromacrogol sclerotherapy for pyloric obstruction due to gastric duplication cysts. CONCLUSION: EUS-FNA combined with lauromacrogol sclerotherapy provides a new option for the treatment of gastrointestinal duplication cysts.

16.
Guang Pu Xue Yu Guang Pu Fen Xi ; 32(8): 2085-8, 2012 Aug.
Artículo en Zh | MEDLINE | ID: mdl-23156757

RESUMEN

Infrared spectra are often corrupted by noise, which may greatly influence the accuracy and precision of the analytical result. To improve the analytical precision, the authors need to denoise the spectrum data first. In the present paper, a spectrum denoising method by the second generation wavelet transform domain thresholding combined with the median filtering is introduced. The spectrum of a certain kind of wheat was used to test the performance of the proposed denoising method. In the experiment,noise with signal to noise ratio 21.17 dB was first added to the spectrum, and then removed by the proposed denoising method. The signal to noise ratio (SNR), the root mean square error (RMSE), the average relative error of the peak value (AREPV) and the average error of the peak position (AEPP) were used to evaluate the performance of the proposed denoising method. Experimental results show that the proposed method can remove the spectrum noise and keep the useful information more effective than Donoho's soft and hard threshold method. At the same time, it can achieve a higher PSNR, a lower RMSE, a lower AREPV and a lower AEPP than the other two denoising methods.

17.
IEEE Trans Neural Netw Learn Syst ; 33(2): 577-586, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33079679

RESUMEN

Finding a desirable sampling estimator has a profound impact on the development of static word embedding models, such as continue-bag-of-words (CBOW) and skip gram (SG), which have been generally accepted as popular low-resource algorithms to generate task-agnostic word representations. Due to the prevalence of large-scale pretrained models, less attention has been paid to these static models in the recent years. However, compared with the dynamic embedding models (e.g., BERT), these static models are straightforward to interpret, cost effective to train, and out-of-box to deploy, thus are still widely used in various downstream models until now. Therefore, it is still of considerable significance to study and improve them, especially the crucial components shared by these static models. In this article, we focus on negative sampling (NS), a key component shared by the sampling-based static models, by investigating and mitigating some critical problems of the sampling core. Concretely, we propose Seeds, a sampling enhanced embedding framework, to learn static word embeddings by a new algorithmic innovation for replacing the NS estimator, in which multifactor global priors are considered dynamically for different training pairs. Then, we implement this framework by four concrete models. For the first two implementations, namely CBOW-GP and SG-GP, both negative words and positive auxiliaries are sampled. And for the other two implementations, CBOW-GN and SG-GN, estimations are simplified by sampling only the negative instances. Extensive experimental results across a variety of standard intrinsic and extrinsic tasks demonstrate that embeddings learned by the proposed models outperform their NS-based counterparts, such as CBOW-NS and SG-NS, as well as other strong baselines.

18.
Iran J Public Health ; 51(6): 1331-1338, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36447965

RESUMEN

Background: There are a large number of psychological problems caused by Internet addiction. We aimed to explore the intervention effect of narrative therapy in combination with Pilates exercise on Internet addiction among adolescents. Method: From July 2021 to October 2021, 42 adolescents with Internet addiction selected from four communities in Yiyang City of China were randomly divided into the intervention and control groups with 21 members in each group. The intervention group participated in the intervention of narrative therapy in combination with Pilates exercise eight times, whereas the control group did not receive any intervention. The 12-item General Health Questionnaire, Self-rating Young's Diagnostic Questionnaire of Internet Addiction, and Positive Affect Subscale were used to measure the psychological indexes of the adolescents before and after the intervention. Results: Compared with those in the control group, the adolescents in the intervention group had an obvious decrease in the degree of Internet addiction with a statistically significant difference before and after the intervention (P < 0.001). After the intervention, the intervention group had significantly higher mental health scores and significantly lower scores for anxiety, depression, social dysfunction, and loss of interest than the control group. After the intervention, the intervention group showed an obvious increase in the score for positive affect with a statistically significant difference before and after the intervention (P < 0.001). Conclusion: The intervention method proposed in this study could effectively solve the problem of Internet addiction among adolescents.

19.
ACS Appl Mater Interfaces ; 14(48): 53658-53666, 2022 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-36400752

RESUMEN

Silicon oxides (SiOx) are one of the most promising anode materials for next-generation lithium-ion batteries owing to their abundant reserve and low lost and high reversible capacity. However, the practical application of SiOx is still hindered by their intrinsically low conductivity and huge volume change. In this regard, we design a novel anode material in which sheet-like SiOx nanosheets are encapsulated in a unique point-to-plane conductive network composed of graphene flakes and nitrogen-doped carbon spheres. This unique composite structure demonstrates high specific capacity (867.7 mAh g-1 at 0.1 A g-1), superior rate performance, and stable cycle life. The electrode delivers a superior reversible discharge capacity of 595.8 mAh g-1 after 200 cycles at 1.0 A g-1 and 287.5 mAh g-1 after 500 cycles at 5.0 A g-1. This work may shed light on the rational design of SiOx-based anode materials for next-generation high-performance lithium-ion batteries.

20.
Spectrochim Acta A Mol Biomol Spectrosc ; 270: 120811, 2022 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-35016063

RESUMEN

Near-infrared (NIR) emitting BiVO4:Yb3+,Tm3+ nanoparticles are synthesized by a new solvothermal strategy using solvents of oleic acid and methanol. The obtained BiVO4:Yb3+,Tm3+ samples show an average particle size of ≈164 nm and exhibit an asymmetry monoclinic crystal structure of BiVO4. At NIR excitation of 980 nm, the BiVO4:Yb3+,Tm3+ sample exhibits a nearly single NIR emission at ≈796 nm with extremely weak blue emissions from Tm3+ ions. These high-energy visible emissions are absorbed by the semiconducting host of BiVO4 that possesses a bandgap of ≈2.2 eV. Therefore, the NIR excitation to a single intense NIR emission fluorescent BiVO4 materials could be a potential ideal probe for deep-tissue high-resolution bioimaging. To validate the ability of BiVO4 materials for bio-applications, we conduct the cytotoxicity experiments. The results show that the cytotoxicity of HeLa cells is negligible at a concentration of 0.2 mg/ml of BiVO4:Yb3+,Tm3+ , and the cell viability approaches 90% at a high dosage of 0.5 mg/ml. The Daphnia magna and Zebrafish treated with nanoparticles (0.5 mg/ml) display bright NIR emission without any background, indicating the excellent in vivo fluorescent imaging capacity of BiVO4:Yb3+,Tm3+ nanoparticles. Our findings offer an environment-friendly strategy to synthesize BiVO4 UCL nanophosphors and provide a promising new class of fluorescent probes for biological applications.


Asunto(s)
Nanopartículas , Pez Cebra , Animales , Células HeLa , Humanos , Nanopartículas/toxicidad , Tamaño de la Partícula
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