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1.
Int J Hypertens ; 2021: 7028942, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34888099

RESUMO

Few studies have considered psychosocial characteristics when investigating the associations between sleep duration and blood pressure (BP). In this study, we took propensity score matching (PSM) to adjust for psychosocial characteristics when comparing BP between individuals with short sleep duration and those with normal sleep duration. A total of 429 participants were included. 72 participants with sleep duration ≤6 h and 65 participants with sleep duration >6 h were matched after PSM. We compared office BP, 24-hour BP, and prevalence of hypertension in the populations before and after PSM, respectively. In the unmatched population, participants with sleep duration ≤6 h were observed with higher office diastolic BP (DBP) and 24-h systolic BP (SBP)/DBP (all P < 0.05). In the matched populations, the differences between the two groups (sleep duration ≤6 h vs. sleep duration >6 h) in office DBP (88.4 ± 10.9 vs. 82.5 ± 11.1 mm Hg; P=0.002), 24-h SBP (134.7 ± 12.0 vs. 129.3 ± 11.6 mm Hg; P=0.009), and 24-h DBP (83.4 ± 9.9 vs. 78.1 ± 10.1 mm Hg; P=0.002) become more significant. Participants with sleep duration ≤6 h only show higher prevalence of hypertension based on 24-h BP data, while analysis after PSM further revealed that these with sleep duration ≤6 h presented about 20% higher prevalence of elevated BP up to office diagnosed hypertension threshold. Therefore, psychosocial characteristics accompanied with short sleep duration should be fully valued in individuals at risks for elevated BP. This trial is registered with NCT03866226.

2.
Front Psychiatry ; 12: 786386, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34867564

RESUMO

The current study examined the influence of pubertal development stage on depression and its psychosocial mechanisms in a non-clinical population of 502 adolescents (244 boys and 258 girls) in China, graded 5 to 8. Results indicated that (1) pubertal development was positively correlated with depression, negative physical self and interpersonal stress. (2) There is a significant gender by pubertal development interaction on the measure of academic self-concept, which is accounted for by decreased academic self in boys but not in girls as a function of pubertal development. (3) Mediation analyses show that increased depression in late compared to pre- puberty is partly mediated by the enhancement of negative physical self and interpersonal stress. These findings suggest that the late stage of puberty is coupled by a higher risk of depression in adolescents partly through increased negative physical self and interpersonal stress.

3.
Artigo em Inglês | MEDLINE | ID: mdl-34857379

RESUMO

Fenton-like catalysts have usually superior catalytic activities, however, some drawbacks of ion leaching and difficult-to-recovery limit their applications. In this work, a hierarchical porous Fe3O4/Co3S4 catalyst was fabricated via a simple phase change reaction to overcome these shortcomings. The introduced iron cooperates with cobalt achieving high-efficiency activation of peroxymonosulfate (PMS) to eliminate Rhodamine B (RhB). The results showed that 0.05 g/L Fe3O4/Co3S4 and 1 mM PMS could quickly remove 100% of 200 mg/L RhB within 20 min, and the removal rate of RhB remained above 82% after 5 cycles. Moreover, the as-prepared Fe3O4/Co3S4 possessed a great magnetic separation capacity and good stability of low metal leaching dose. Radical quenching experiments and electron paramagnetic resonance (EPR) techniques proved that sulfate radicals (SO4•-) were the dominant reactive oxygen species responding for RhB degradation. X-ray photoelectron spectroscopy (XPS) pointed out that the synergism of sulfur promoted the cycling of Co3+/Co2+ and Fe3+/Fe2+, boosting the electron transfer between Fe3O4/Co3S4 and PMS. Moreover, the degradation pathways of RhB were deduced by combining liquid chromatography-mass spectrometry (LC-MS) analysis and density functional theory (DFT) calculations. The toxicities of RhB and its intermediates were evaluated as well, which provided significant assistance in the exploration of their ecological risks.

4.
Br J Clin Pharmacol ; 2021 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-34931372

RESUMO

BACKGROUNDS: Hyzetimibe (HS-25), a new drug approved for hypercholesterolemia, exhibits obvious enterohepatic recirculation (EHC) after oral administration. Up to now, little is known about the kinetics of HS-25. Therefore, we performed this population pharmacokinetic (PopPK) analysis aiming to describe the PK behavior of HS-25 and its main metabolite (M1), and to identify significant covariates contributing to the variability. METHODS: The plasma concentration data used for modeling were obtained from an open-label, single-dose, randomized, two-period crossover bioequivalence study. PopPK modeling was performed with NONMEM 7.4.1 using nonlinear mixed effect modeling approach. Goodness of fit plots, bootstrap and visual predictive check were used for model internal validation. Data from another study was used for external validation. RESULTS: Data from 16 male and 8 female subjects were used in the PopPK analysis. HS-25 and M1 concentrations in the modeling cohort were well described by a one-compartment model incorporating first-pass metabolism and a gallbladder compartment, accounting for the EHC process. The release kinetic of gall was mimicked by a first-order constant plus a switch on/off effect. Body weight was identified as a significant covariate effecting on the clearance and apparent distribution volume of HS-25, as well as kmg , the transfer rate from metabolite compartment to gallbladder compartment. Internal and external validation demonstrated an acceptable predictive ability of the final model. CONCLUSIONS: We present the first PopPK model describing HS-25 and M1 concentrations simultaneously, with the EHC process considered. The modeling and simulation results could provide reference for the clinical use of HS-25.

5.
Elem Sch J ; 121(4): 609-634, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34924590

RESUMO

Teachers' perceptions of their students' academic skills can affect students' achievement and may be influenced by unrelated student characteristics such as socioeconomic status (SES). In this ad hoc randomized controlled trial, teachers (n = 28) were randomly assigned to receive training on using assessment to guide literacy instruction, Assessment-to-Instruction (A2i), or on Math PALS (control). Teachers rated students' (n = 446) academic competence. A2i teachers' ratings did not vary by SES, and their ratings correlated more strongly with students' literacy and mathematics assessment scores compared with those of the control teachers. Control teachers generally underestimated lower SES students' academic competence; underestimation was greater at more affluent schools. Teachers' ratings of students' academic competence predicted reading and mathematics outcomes. Thoughtful use of assessments to guide instruction appeared to improve the precision of teachers' ratings of students' academic competence, improve student outcomes, and reduce potential teacher biases about children from higher-poverty families.

6.
Med Phys ; 2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-34967464

RESUMO

PURPOSE: Many diseases can simultaneously involve renal arteries and the adjacent abdominal aorta. The study proposed a free-breathing three-dimensional (3D) isotropic-resolution MR sequence for simultaneous vessel wall imaging of bilateral renal arteries and adjacent abdominal aorta. METHODS: A respiratory triggered isotropic-resolution sequence which combined the improved motion-sensitized driven-equilibrium (iMSDE) preparation with the spoiled gradient recalled (SPGR) readout (iMSDE-SPGR) was proposed for simultaneous vessel wall imaging of renal arteries and abdominal aorta. The proposed iMSDE-SPGR sequence was optimized by positioning spatial saturation pulses (i.e. REST slabs) elaborately to further alleviate respiratory and gastrointestinal motion artifacts and selecting appropriate first-order gradient moment (m1 ) of the iMSDE preparation. Thirteen healthy subjects and thirteen patients with renal artery stenosis (RAS) underwent simultaneous vessel wall imaging with the optimized iMSDE-SPGR sequence at 3.0T. Signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and morphology of renal arterial wall and aortic wall were measured. Reproducibility of intra-observer, inter-observer and scan-rescan (n = 13 healthy subjects) in measuring SNR, CNR and morphology was evaluated. For the reproducibility test, the agreement was determined using intraclass correlation coefficients (ICC) and the differences were compared using paired-t test or non-parametric Wilcoxon test when appropriate. Bland-Altman plots were used to calculate the bias between observers and between scans. RESULTS: The proposed iMSDE-SPGR sequence was feasible for simultaneous vessel wall imaging both in the healthy subjects and the patients. The sequence showed good to excellent inter-observer (ICC:0.615-0.999), excellent intra-observer (ICC:0.801-0.998) and scan-rescan (ICC:0.768-0.998) reproducibility in measuring morphology, SNR and CNR. There were no significant differences in SNR, CNR and morphology measurements between observers and between scans (all P>0.05). Bland-Altman plots showed small bias in assessing SNR, CNR and morphology. DATA CONCLUSION: The proposed free-breathing 3D isotropic-resolution iMSDE-SPGR technique is feasible and reproducible for simultaneous vessel wall imaging of bilateral renal arteries and adjacent abdominal aorta. This article is protected by copyright. All rights reserved.

8.
Water Res ; 207: 117811, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34763277

RESUMO

Hollow fiber membrane contactor (HFMC) is a promising technology for removing or recovering wastewaters' volatile components. Developing a rational design method is very important for guiding its further application. In this study, we proposed a method to design the multi-stage open-loop hollow fiber membrane contactor (HFMC) employing shell-side influent. In addition, a three-stage HFMC was designed to capture ammonia from real hydrolyzed human urine. A continuous 1344 h performance was conducted. The results showed that the experimental effluent total ammonium nitrogen (TAN) concentration and ammonia mass transfer coefficient matched the predicted results well, which indicated that the design method was feasible and accurate. The three-stage HFMC showed excellent ammonia capture capacity with a TAN recovery efficiency of 93.29%, and the final effluent TAN concentration was 30.98±14.70 mg/L which met our design requirement (lower than 50 mg/L). More than 98.92% of the inorganic ions and 96.85% of the organic matter were retained in the effluent. The stripping solution after ammonia capture was the high-purity ammonium sulfate solution with low concentration of small molecular weight hydrophilic organic substances. The inorganic and organic membrane fouling was mild and randomly distributed. The inorganic membrane fouling was attributed to the deposition of calcium-, magnesium-, phosphate-related inorganic compounds, while the organic membrane fouling was mainly protein and carbohydrate. After the ammonia capture process, the surface hydrophobicity and pore properties of the membranes had no significant changes. These results demonstrated that the multi-stage open-loop HFMC could be a potential alternative for ammonia recovery from the high concentration of ammonium nitrogen wastewater.

9.
Prep Biochem Biotechnol ; : 1-11, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34747342

RESUMO

In this study, a high protease-producing strain was screened by spread plate method and identified by molecular biology and morphological identification. It was identified as Bacillus sp. LCB14. A neutral protease gene was cloned and heterologous expressed by B. subtilis SCK6. Then, the recombinant protease was used to dehair the goat skins. The fermentation conditions of neutral protease production by B. subtilis SCK6 were optimized. The single factor experiments, Plackett-Burma experiment, and response surface method were conducted to determine fermentation medium and culture conditions. The optimized medium contained corn meal 49 g/L, soluble starch 28 g/L, soybean meal 17 g/L, corn steep liquor powder 8 g/L, yeast extract 10 g/L, Na2HPO4 2.3 g/L, KH2PO4 1.9 g/L, MgSO4 0.5 g/L, MnCl2 0.1 g/L and ZnSO4 0.05 g/L. The optimized culture conditions were 35 °C and pH 7.0. Under the optimum conditions, the recombinant strain reached 33467.28 U/mL after 72 hr ferment. Moreover, by fed batch in 30 L fermenters, neutral protease production reached 39,440.78 U/mL and shortened fermentation time from 72 hr to 46 hr. Finally, the crude enzyme was utilized to replace sodium sulfide for dehairing of goatskins. The enzymatic dehaired pelts were white, smooth, and soft; the grain side of enzymatic dehaired pelts were clear; there was no obvious damage to the grain side of enzymatic dehaired pelts by visual observation and tactile test. Furthermore, there were no hair roots, hair follicles and other glands in enzymatic dehaired belts, and the collagen fibers of enzymatic dehaired belt were dispersed well by histological analysis.

10.
Med Biol Eng Comput ; 2021 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-34807355

RESUMO

Damaged nerve function can be repaired by applying external stimuli, and the selective stimulation of nerve fibers is the highest goal of nerve functional repair. This paper proposes a method of using multichannel near-infrared lasers to achieve the selective stimulation of axons in different areas in a mixed nerve bundle. An exposed bullfrog sciatic nerve was considered the object of study to realize the selective stimulation. A model was established by using COMSOL Multiphysics to simulate the temperature distribution of nerves under multichannel near-infrared laser stimulation. The results of this model showed that by changing the distance between the laser fiber and the nerve (d) or the power of the 4 lasers (P), the axons at different parts of the nerve bundle may be selectively stimulated. If only the axons located in the center are selected to be activated, it is necessary to set the d and P value in the four directions to the same value. If only axons on the nerve edge are selected for activation, we can reduce the d value of the nearest laser (or increase P) and increase the d value of lasers in other directions (or decrease P). If only axons in the shallow area below the surface between the two lasers are selected for activation, it is necessary to reduce the d value of the laser in two directions close there (or increase P) and increase the d value of the laser in the other two directions (or decrease P). If only the axons of the superficial region on the coordinate axis are activated, the d value of the laser in the farthest direction can be increased (or decrease P) and the d value of the other three lasers can be reduced (or increase P). Moreover, the results of animal experiments further verify the feasibility of our method to realize selective activation of the axons.

11.
Artigo em Inglês | MEDLINE | ID: mdl-34757657

RESUMO

Ensartinib is a promising, aminopyridazine-based small molecule that potently inhibits anaplastic lymphoma kinase. This random, two-period, crossover study evaluated the effects of food on the pharmacokinetics of ensartinib after a single dose (225 mg) in healthy Chinese subjects. The pharmacokinetic parameters of ensartinib were calculated using non-compartmental analysis. Twenty-four Chinese healthy subjects aged 20-44 years were included in this study. The area under the concentration-time curve of ensartinib was approximately 25% lower after the intake of a high-fat, high-calorie meal prior to dosing, whereas the maximum plasma concentration was decreased by approximately 37%, illustrating the statistically significant effect of food on ensartinib pharmacokinetics. In addition, food intake prolonged the absorption phase of ensartinib (median time to maximum plasma concentration, from 4.5 to 6 h). Population pharmacokinetic (PopPK) analysis was conducted using NONMEM, and the influences of food, age, sex, body weight, and body mass index were studied via covariate analysis. In this analysis, ensartinib plasma concentrations were best described by a one-compartment model with Weibull absorption. The final model included food and age as covariates on apparent distribution and apparent clearance. Based on the final PopPK model, food was identified as a significant covariate for apparent clearance, apparent volume of distribution, and absorption rate constant, consistent with the results of non-compartmental pharmacokinetic analysis.

12.
New Phytol ; 2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34812499

RESUMO

The development of viable pollen determines male fertility, and is crucial for reproduction in flowering plants. Phytochrome interacting factor 3 (PIF3) acts as a central regulator of plant growth and development, but its relationship with pollen development has not been determined. Through genetic, histological and transcriptomic analyses, we identified an essential role for SlPIF3 in regulating tomato (Solanum lycopersicum) pollen development. Knocking out SlPIF3 using clustered regularly interspaced short palindromic repeats/CRISPR-associated protein 9 resulted in pollen mitosis I arrest, and a failure to form viable pollen. We further demonstrated that both glutamate synthase 1 (SlGLT1) and cell wall invertase 9 (SlCWIN9), involved in auxin and sugar homeostasis, respectively, colocalised with SlPIF3 in the anthers and were directly regulated by SlPIF3. Knockout of either SlGLT1 or SlCWIN9 phenocopied the pollen phenotype of SlPIF3 knockout (Slpif3) lines. Slpif3 fertility was partially restored by exogenous auxin indole-3-acetic acid in a dose-dependent manner. This study reveals a mechanism by which SlPIF3 regulates pollen development and highlights a new strategy for creating hormone-regulated genic male sterile lines for tomato hybrid seed production.

13.
China CDC Wkly ; 3(23): 495-499, 2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34594921

RESUMO

What is already known on this topic?: The morbidity and mortality of chronic obstructive pulmonary disease (COPD) is associated with adverse weather and air pollution. However, COPD patients are not able to be alerted in advance of high risk environments. What is added by this report?: This prospective controlled trial conducted in Pudong New Area of Shanghai from October 2019 to April 2020 provided evidence of COPD risk forecasting service on the reductions in visits and costs of COPD patients in outpatient and emergency departments in China for the first time. What are the implications for public health practice?: This study suggests that COPD risk forecasting service could be integrated into existing COPD management in public health to improve the health and economic outcomes.

14.
Artigo em Inglês | MEDLINE | ID: mdl-34628186

RESUMO

A simple, selective, rapid, and reliable ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed and validated to determine CX3002 in human plasma using CX3002-d3 as the internal standard (IS). After a rapid protein precipitation with acetonitrile (3:1, v/v), the chromatographic separation of CX3002 and IS was performed on a Thermo Hypersil GOLD C18 column (2.1 mm × 50 mm, 1.9 µm) with gradient elution at a flow rate of 0.4 ml/min. Gradient elution was achieved with mobile phase A consisting of water containing 0.1% formic acid and 5 mmol/L ammonium formate and mobile phase B consisting of methanol containing 0.1% formic acid. The detection was performed on AB SCIEX QTRAP® 5500 tandem mass spectrometry in the positive ion mode. Multiple reactions monitoring (MRM) was used for quantitative analysis at transition of m/z 460.3 â†’ 199.3 for CX3002 and m/z 463.3 â†’ 202.3 m/z for IS. The method was fully validated and displayed good linearity over a concentration range of 0.2-400 ng/mL with the correlation coefficient above 0.997. The intra-run and inter-run precision (coefficient of variation, CV) ranged from 0.60%-16.46% and the accuracy bias ranged from -7.09%-9.75%. The mean IS-normalized extraction recovery ranged from 98.30% to 104.52%. The CV(%) of IS-normalized matrix factors at the low and high QC concentration were 4.09% and 1.68%, respectively. The storage stability under different conditions was in accordance with the bioanalytical guidelines. The method was successfully applied to the pharmacokinetic study of CX3002 (30 mg) in healthy Chinese subjects.

15.
Artigo em Inglês | MEDLINE | ID: mdl-34665742

RESUMO

In this article, Hopfield neural networks system with time-varying delays driven by nonlinear colored noise is introduced. The existence and globally exponential stability of stationary solutions are investigated for such random delay neural networks systems, which may be regarded as a generalization for the case of the constant equilibrium point in the literature. Moreover, the synchronization behavior of linearly coupled delay Hopfield neural networks driven by nonlinear colored noise is investigated at the level of the random attractor. Finally, illustrative examples and numerical simulations are provided to show the effectiveness of the obtained results.

16.
Neuropsychologia ; 161: 108014, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34478757

RESUMO

Individuals with mild cognitive impairment (MCI) have deficits in goal-directed top-down and stimulus-driven bottom-up attentional control. However, it remains unclear whether and how the interaction between the two processes is altered in individuals with MCI. We collected electroencephalography (EEG) data from 30 older adults with MCI and 30 demographically matched healthy controls (HCs) when they were performing a perceptual decision-making task, in which we manipulated the cognitive load involved in task-relevant top-down processing and the surprise level involved in task-irrelevant bottom-up processing. We found the significant group difference in the interaction between top-down and bottom-up processes. HCs showed enlarged P3 and strengthened event-related microstate C on high (vs. low) surprise level trials under high cognitive load, while there was no such surprise effect suggesting distraction under low cognitive load. In contrast, participants with MCI showed increased P2 and P3 amplitudes and strengthened microstates C and D on high (vs. low) surprise level trials under low cognitive load yet no surprise effect under high load. These results suggested that participants with MCI were distracted by task-irrelevant information under low cognitive load, while under high load, they might experience a passive inhibition on the task-irrelevant bottom-up processing because of the exhaustion of attentional resources; in addition, this altered interaction observed in the MCI group occurred at the stages of selective attention and uncertainty reduction.


Assuntos
Disfunção Cognitiva , Idoso , Atenção , Eletroencefalografia , Humanos , Inibição Psicológica , Incerteza
17.
Front Psychol ; 12: 619303, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34484020

RESUMO

Even though the coronavirus disease (COVID-19) has limited consumption, individuals continue to plan post-pandemic consumption activities to get rid of the stress caused by consumption repression. Building on Maslow's theory of needs and Herzberg's two-factor theory, our research categorizes consumption into fundamental ("must-have" products that fulfill the physical needs of individuals), hygiene (maintaining the security needs of consumers), and motivational consumption (enhancing well-being of individuals). Based on empirical data of purchase behavior and consumption expectation before, during, and after the pandemic in China, we identify how consumption repression induces psychological distress, via a sense of feeling threatened, lacking control, or lacking freedom, and how the expectation of future consumption alleviates that stress. Results show that fundamental consumption leads to psychological distress; hygiene consumption can both result in and reduce stress; and motivational consumption can reduce stress. Our findings provide new insights into the relationship between consumption and psychological distress through new theoretical formulations. The results can be applied by marketers attempting to understand purchase decision-making and by policymakers supporting both citizens and commerce during social emergencies.

18.
Metallomics ; 13(10)2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34477877

RESUMO

Selenium (Se) is a component of many enzymes and indispensable for human health due to its characteristics of reducing oxidative stress and enhancing immunity. Human beings take Se mainly from Se-containing crops. Taking measures to biofortify crops with Se may lead to improved public health. Se accumulation in plants mainly depends on the content and bioavailability of Se in soil. Beneficial microbes may change the chemical form and bioavailability of Se. This review highlights the potential role of microbes in promoting Se uptake and accumulation in crops and the related mechanisms. The potential approaches of microbial enhancement of Se biofortification can be summarized in the following four aspects: (1) microbes alter soil properties and impact the redox chemistry of Se to improve the bioavailability of Se in soil; (2) beneficial microbes regulate root morphology and stimulate the development of plants through the release of certain secretions, facilitating Se uptake in plants; (3) microbes upregulate the expression of certain genes and proteins that are related to Se metabolism in plants; and (4) the inoculation of microbes give rise to the generation of certain metabolites in plants contributing to Se absorption. Considering the ecological safety and economic feasibility, microbial enhancement is a potential tool for Se biofortification. For further study, the recombination and establishment of synthesis microbes is of potential benefit in Se-enrichment agriculture.

19.
Molecules ; 26(15)2021 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-34361556

RESUMO

Wastewater emissions from textile factories cause serious environmental problems. Manganese peroxidase (MnP) is an oxidoreductase with ligninolytic activity and is a promising biocatalyst for the biodegradation of hazardous environmental contaminants, and especially for dye wastewater decolorization. This article first summarizes the origin, crystal structure, and catalytic cycle of MnP, and then reviews the recent literature on its application to dye wastewater decolorization. In addition, the application of new technologies such as enzyme immobilization and genetic engineering that could improve the stability, durability, adaptability, and operating costs of the enzyme are highlighted. Finally, we discuss and propose future strategies to improve the performance of MnP-assisted dye decolorization in industrial applications.


Assuntos
Corantes/química , Enzimas Imobilizadas/química , Peroxidases/química , Têxteis , Águas Residuárias/química , Biodegradação Ambiental , Catálise
20.
J Healthc Eng ; 2021: 7799100, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34457221

RESUMO

Microexpression can manifest the real mood of humans, which has been widely concerned in clinical diagnosis and depression analysis. To solve the problem of missing discriminative spatiotemporal features in a small data set caused by the short duration and subtle movement changes of microexpression, we present a dual-stream spatiotemporal attention network (DSTAN) that integrates dual-stream spatiotemporal network and attention mechanism to capture the deformation features and spatiotemporal features of microexpression in the case of small samples. The Spatiotemporal networks in DSTAN are based on two lightweight networks, namely, the spatiotemporal appearance network (STAN) learning the appearance features from the microexpression sequences and the spatiotemporal motion network (STMN) learning the motion features from optical flow sequences. To focus on the discriminative motion areas of microexpression, we construct a novel attention mechanism for the spatial model of STAN and STMN, including a multiscale kernel spatial attention mechanism and global dual-pool channel attention mechanism. To obtain the importance of each frame in the microexpression sequence, we design a temporal attention mechanism for the temporal model of STAN and STMN to form spatiotemporal appearance network-attention (STAN-A) and spatiotemporal motion network-attention (STMN-A), which can adaptively perform dynamic feature refinement. Finally, the feature concatenate-SVM method is used to integrate STAN-A and STMN-A to a novel network, DSTAN. The extensive experiments on three small spontaneous microexpression data sets of SMIC, CASME, and CASME II demonstrate the proposed DSTAN can effectively cope with the recognition of microexpressions.

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