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1.
Chem Biodivers ; 21(4): e202301736, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38451006

RESUMO

In recent years, the research of mitochondrial dysfunction in depression has drawn the focus of researchers. Our research group previously found that Xiaoyao San (XYS) has improved the mitochondrial structure and the blocked tricarboxylic acid cycle (TCA cycle) in the hippocampal tissue of chronic unpredictable mild stress (CUMS) rats. However, the specific targets and active components of XYS remain unclear, and the potential to improve hippocampal mitochondrial TCA cycle disorder was also unexplored. In this research, a strategy to combine stable isotope-resolved metabolomics (SIRM), network pharmacology and transmission electron microscopy (TEM) was used to explore the potential, targets of action, and active components of XYS to improve hippocampal mitochondrial TCA cycle disorder of CUMS rats. The results of TEM showed that the ultrastructure of hippocampal mitochondria could be improved by XYS. A combination of SIRM and molecular docking showed that pyruvate carboxylase (PC), ATP citrate lyase (ACLK), glutamate dehydrogenase (GLDH), glutamate oxaloacetate transaminase (GOT) and pyruvate dehydrogenase (PDH) were targets of XYS to improve TCA cycle disorder. In addition, troxerutin was found to be the most potential active component of XYS to improve TCA cycle disorder. The above research results can provide new insights for the development of antidepressant drugs.


Assuntos
Medicamentos de Ervas Chinesas , Farmacologia em Rede , Ratos , Animais , Simulação de Acoplamento Molecular , Antidepressivos/farmacologia , Medicamentos de Ervas Chinesas/farmacologia
2.
J Proteome Res ; 21(3): 788-797, 2022 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-34699232

RESUMO

Depression is a common psychopathological state or mood disorder syndrome. The serious risks to human life and the inadequacy of the existing antidepressant drugs have driven us to understand the pathogenesis of depression from a new perspective. Our research group has found disturbances in glucose catabolism in both depression and nephrotic syndrome. What are the specific metabolic pathways and specificities of glucose catabolism disorders caused by depression? To address the above scientific questions, we creatively combined traditional metabolomics technology with stable isotope-resolved metabolomics to research the glucose catabolism of the corticosterone-induced PC12 cell damage model and the adriamycin-induced glomerular podocyte damage model. The results showed an increased flux of pyruvate metabolism in depression. The increased flux of pyruvate metabolism led to an activation of gluconeogenesis in depression. The disturbed upstream metabolism of succinate caused the tricarboxylic acid cycle (TCA cycle) to be blocked in depression. In addition, there were metabolic disturbances in the purine metabolism and pentose phosphate pathways in depression. Compared with nephrotic syndrome, pyruvate metabolism, the TCA cycle, and gluconeogenesis metabolism in depression were specific. The metabolic pathways researched above are likely to be important targets for the efficacy of antidepressants.


Assuntos
Depressão , Síndrome Nefrótica , Corticosteroides , Animais , Ciclo do Ácido Cítrico , Depressão/induzido quimicamente , Feminino , Glucose/metabolismo , Humanos , Isótopos , Masculino , Metabolômica/métodos , Células PC12 , Ácido Pirúvico , Ratos
3.
Small ; 18(34): e2106943, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35908810

RESUMO

Degraded population inversion (PI) at elevated temperature, regarded as an important temperature degradation factor in terahertz quantum cascade lasers (THz QCL), has hindered the widespread use of these devices. Herein, the mechanism of the temperature degradation of PI is investigated microscopically. It is demonstrated that the limited extraction efficiency of the extraction system dominates the decrease of PI at elevated temperatures. To be specific, the increased temperature brings about intense thermally activated longitudinal optical phonon scattering, leading to large amounts of electrons scattering to lower level state. In this case, the resonant-phonon extraction system is incapable of depleting all the electrons from lower level states. So even though the resonant-tunneling injection seems efficient enough to compensate the electron runoff at the upper state, the electron density at lower level state increases and the overall PI turns out lower. In addition, it is found that strong electron-ionized donor separation at high temperature can induce level misalignment, which can stagger the optimal conditions of injection and extraction. Also, the extraction efficiency gets lower as the extraction system requires accurate coupling between several energy levels.


Assuntos
Lasers Semicondutores , Radiação Terahertz , Desenho de Equipamento , Análise de Falha de Equipamento , Temperatura
4.
Nanotechnology ; 34(3)2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-35803211

RESUMO

In this paper, a strategy to finely modulate the energy band structure to control the carrier confinement capability of digital alloys (DA) is proposed. Strain analysis shows that As and Sb atoms are exchanged within the AlAsSb DA. The bottom of the corrected potential well is low on the left and high on the right in the growth direction, resulting in a higher band offset of the AlSb potential barrier layer on the left side of the potential well than on the right side. The modulation of the band leads to a higher probability of electron tunneling in DA under the action of an electric field opposite to the growth direction. Conversely, it is difficult for the electrons to tunnel into the lower energy level potential wells. TheI-Vcurve of DA shows that the current value under positive bias is significantly smaller than the value under negative bias when the voltage is higher. The measured results correspond perfectly with the modified energy band model, which verifies the feasibility of energy band modulation. This is important for the structural design of DA and the reduction of dark current in optoelectronic devices.

5.
Molecules ; 27(22)2022 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-36431927

RESUMO

The overall electrochemical performance of natural graphite is intimately associated with the solid electrolyte interphase (SEI) layer developed on its surface. To suppress the interfacial electrolyte decomposition reactions and the high irreversible capacity loss relating to the SEI formation on a natural graphite (NG) surface, we propose a new design of the artificial SEI by the functional molecular cross-linking framework layer, which was synthesized by grafting acrylic acid (AA) and N,N'-methylenebisacrylamide (MBAA) via an in situ polymerization reaction. The functional polymeric framework constructs a robust covalent bonding onto the NG surface with -COOH and facilitates Li+ conduction owing to the effect of the -CONH group, contributing to forming an SEI layer of excellent stability, flexibility, and compactness. From all the benefits, the initial coulombic efficiency, rate performance, and cycling performance of the graphite anode are remarkably improved. In addition, the full cell using the LiNi0.5Co0.2Mn0.3O2 cathode against the modified NG anode exhibits much-prolonged cycle life with a capacity retention of 82.75% after 500 cycles, significantly higher than the cell using the pristine NG anode. The mechanisms relating to the artificial SEI growth on the graphite surface were analyzed. This strategy provides an efficient and feasible approach to the surface optimization for the NG anode in LIBs.


Assuntos
Grafite , Eletrodos , Eletrólitos
6.
Small ; 17(26): e2100510, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34081390

RESUMO

The design and fabrication of transition metal dichalcogenides (TMDs) are of paramount significance for water-splitting process. However, the limited active sites and restricted conductivity prevent their further application. Herein, a polarization boosted strategy is put forward for the modification of TMDs to promote the absorption of the intermediates, leading to the improved catalytic performance. By the forced assembly of TMDs (WS2 as the example) and carbon nanotubes (CNTs) via spray-drying method, such frameworks can remarkably achieve low overpotentials and superior durability in alkaline media, which is superior to most of the TMDs-based catalysts. The two-electrode cell for water-splitting also exhibits perfect activity and stability. The enhanced catalytic performance of WS2 /CNTs composite is mainly owing to the strong polarized coupling between CNTs and WS2 nanosheets, which significantly promotes the charge redistribution on the interface of CNTs and WS2 . Density functional theory (DFT) calculations show that the CNTs enrich the electron content of WS2 , which favors electron transportation and accelerates the catalysis. Moreover, the size of WS2 is restricted caused by the confinement of CNTs, leading to the increased numbers of active sites, further improving the catalysis. This work opens a feasible route to achieve the optimized assembling of TMDs and CNTs for efficient water-splitting process.

7.
Small ; 17(30): e2100559, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34185440

RESUMO

While metal-based electrocatalysts have garnered extensive attention owing to the large variety of enzyme-mimic properties, the search for such highly-efficient catalysts still relies on empirical explorations, owing to the lack of predictive indicators as well as the ambiguity of structure-activity relationships. Notably, surface electronic structures play a crucial role in metal-based catalysts yet remain unexplored in enzyme-mimics. Herein, the authors investigate the electronic structure as a possible indicator of electrocatalytic activities of H2 O2 decomposition and glucose oxidation using Pd@Pt core-shell nanocrystals as a well-defined platform. The electron densities of the Pd@Pt are modulated with the correlation of strain through precise control of surface orientation and the number of atomic layers. The close relationships between the electrocatalytic activities and the surface charge accumulation are found, in which the increase of the electron accumulation can enhance both the enzyme-mimic activities. As a result, the Pd@Pt3L icosahedra with compressive strain in Pt shells exhibit the highest electrocatalytic activities for H2 O2 decomposition and glucose oxidation. Such systematic and comprehensive study provides the structure-activity relationships and paves a new way for the rational design of metal-based electrocatalysts. Especially, the charge accumulation degrees may serve as a general performance indicator for metal-based catalysts.


Assuntos
Nanopartículas , Platina , Catálise , Eletrônica , Paládio
8.
Small ; 16(42): e2003905, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32996264

RESUMO

Three-dimensional (3D) materials assembled by 2D layered lamella can provide abundant interfaces which are greatly advantageous for high-performance microwave absorbers. Herein, accordion-like CeO2- x /reduced graphene oxide (CeO2- x /RGO) hybrid materials can be successfully synthesized by a solvothermal and hydrothermal method, which are composed of laminated RGO sheets and confined CeO2- x nanoparticles (NPs). The multilayer structure is attributed to the process of Ce-MOF dissolving into NPs, then the NPs combining with graphene oxide (GO) to induce the 2D GO assembled into 3D accordion-like composites. The 3D accordion-like CeO2- x /RGO simultaneously utilizes the insulated CeO2- x and highly conductive RGO to assemble into the laminated structure with moderate electromagnetic parameters. The 3D-laminated lightweight CeO2- x /RGO composite exhibits excellent attenuation ability of an ultrabroad bandwidth (5.84 GHz) and a maximum reflection loss (-50.6 dB) which can be ascribed from the glorious impedance matching, synergistic effect between RGO sheets and the embedded CeO2- x NPs. An off-axis electron holography is carried out to visualize the spatial electrical potential and charge distribution around the CeO2- x /RGO heterojunction, which clarifies the dipole polarization and interfacial polarization. This work enlightens a simple strategy to fabricate an excellent 3D laminated RGO-based microwave absorber.

9.
Small ; 15(15): e1900069, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30859742

RESUMO

The combination of high-capacity and long-term cycling stability is an important factor for practical application of anode materials for lithium-ion batteries. Herein, Nix Mny Coz O nanowire (x + y + z = 1)/carbon nanotube (CNT) composite microspheres with a 3D interconnected conductive network structure (3DICN-NCS) are prepared via a spray-drying method. The 3D interconnected conductive network structure can facilitate the penetration of electrolyte into the microspheres and provide excellent connectivity for rapid Li+ ion/electron transfer in the microspheres, thus greatly reducing the concentration polarization in the electrode. Additionally, the empty spaces among the nanowires in the network accommodate microsphere volume expansion associated with Li+ intercalation during the cycling process, which improves the cycling stability of the electrode. The CNTs distribute uniformly in the microspheres, which act as conductive frameworks to greatly improve the electrical conductivity of the microspheres. As expected, the prepared 3DICN-NCS demonstrates excellent electrochemical performance, showing a high capacity of 1277 mAh g-1 at 1 A g-1 after 2000 cycles and 790 mAh g-1 at 5 A g-1 after 1000 cycles. This work demonstrates a universal method to construct a 3D interconnected conductive network structure for anode materials.

10.
Small ; 15(36): e1902885, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31310052

RESUMO

Core@shell structures have been attracting extensive attention to boost microwave absorption (MA) performance due to the unique interfacial polarization. However, it still remains a challenge to synthesize sophisticated 1D semiconductor-based materials with excellent MA competence. Herein, a hierarchical cable-like TiO2 @Fe3 O4 @PPy is fabricated by a sequential process of solvothermal treatment and polymerization. The complex permittivity of ternary composites can be optimized by tunable PPy coating thickness to improve the loss ability. The maximum reflection loss can reach -61.8 dB with a thickness of 3.2 mm while the efficient absorption bandwidth can achieve over 6.0 GHz, which involves the X and Ku band at only a 2.2 mm thickness. Importantly, the heterojunction contacts constructed by PPy-Fe3 O4 and Fe3 O4 -TiO2 contribute to the enhanced polarization loss. Besides, the configuration of magnetic Fe3 O4 sandwiched between dielectric TiO2 and PPy facilitates the magnetic stray field to radiate into the TiO2 core and out of the PPy shell, which significantly promotes magnetic-dielectric synergy. Electron holography validates the distinct charge distribution and magnetic coupling. The new findings might shed light on novel structures for functional core@shell composites and the design of semiconductor-based materials for microwave absorption.

11.
Small ; 15(18): e1900900, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30957426

RESUMO

A novel strategy is used to design large-scale polarized carbon-based dielectric composites with sufficient interaction to electromagnetic waves. Highly uniform polar zinc oxide arrays are vertically grown on a flexible conductive carbon cloth substrate (CC@ZnO) via an in situ orientation growth process. Anion regulation is found to be a key factor to the morphology of hierarchical ZnO arrays including single-rod, cluster and tetrapod-shaped. As a typical dielectric loss hybrid composite, the electromagnetic parameters of the CC@ZnO system and charge density distribution in polarized ZnO rods confirm that the 3D intertwined carbon cloth is used as a conductive network to provide ballistic electron transportation. Moreover, the defect-rich ZnO arrays are well in contact with the CC substrate, favoring interface polarization, multiscattering, as well as impedance matching. Surprisingly, the efficient absorption bandwidth of the CC@ZnO-1 composite can reach 10.6 GHz, covering all X and Ku bands. The oriented ZnO possesses oxygen vacancies and exposure to a large amount of intrinsic polar surfaces, encouraging the polarization behavior under microwave frequency. Optimized CC@ZnO materials exhibit fast electron transportation, strong microwave energy dissipation, and superior wide absorption. The results suggest that the CC@ZnO composites have promising potential as flexible, tuning, and broadband microwave absorbers.

12.
Small ; 15(27): e1900837, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31018045

RESUMO

Interfaces in semiconductor heterostructures is of continuously greater significance in the trend of scaling materials down to the atomic limit. Since atoms tend to behave more irregularly around interfaces than in internal materials, accurate energy band alignment becomes a major challenge, which determines the ultimate performance of devices. Therefore, a comprehensive understanding of the interplay between heterointerface, energy band, and macro-performance is desiderated. Here, such interplay is explored by investigating asymmetric heterointerfaces with identical fabrication parameters in multiple-quantum-well lasers. The unexpected asymmetry derives from the atomic discrepancy around heterointerfaces, which ultimately improves the optical property through altered valence band offsets. Strain and charge distribution around heterointerfaces are characterized via geometric phase analysis and in situ bias electron holography, respectively. Combining experiments with theories, arsenic-enrichment at one of the interfaces is considered the origin of asymmetry. To reveal actual band alignment, valence band model is modified focusing on the transition around heterojunctions. The enhanced photoluminescence intensity reflects the alleviation of hole confinement insufficiency and the enlargement of valence band offset. The results help to advance the understanding of the general problem of interface in nanostructures and provide guidance applicable to various scenarios for micro-macro correlation.

13.
Small ; 14(7)2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29251416

RESUMO

Herein, Ni and Zn elements are doped simultaneously in MnCO3 and microspheric Mnx Niy Znz CO3 is successfully obtained. Atomic mapping images reveal that the Ni and Zn elements have been successfully doped in MnCO3 and thus the prepared sample is not a mixture of MnCO3 , NiCO3 , and ZnCO3 . It is the first time that the atomic mapping images of ternary transition metal carbonates have been demonstrated so far. The scanning transmission electron microscopy - annular bright field (STEM-ABF) image successfully confirms the formation of oxygen vacancies in Mnx Niy Znz CO3 , which is beneficial to improve the electrical conductivity. The evolution of the microstructure from crystal to amorphization during cycling process confirmed by the fast Fourier transform patterns effectively lowers the overpotential of the conversion reaction and accelerates the conversion between Mn2+ and much higher valence of Mn element, contributing to the superior capacity of Mnx Niy Znz CO3 electrode. As anode material for lithium-ion batteries, the prepared Mnx Niy Znz CO3 exhibits excellent long-term cycling stability and outstanding rate performance, delivering the superior reversible discharge capacities of 1066 mA h g-1 at 500 mA g-1 after 500 cycles and 760 mA h g-1 at 1 A g-1 after 1000 cycles. It is the first time that Mnx Niy Znz CO3 has been synthesized and used as anode for lithium-ion batteries so far.

14.
Small ; 14(32): e1801007, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30009580

RESUMO

The ingenious design of a freestanding flexible electrode brings the possibility for power sources in emerging wearable electronic devices. Here, reduced graphene oxide (rGO) wraps carbon nanotubes (CNTs) and rGO tightly surrounded by MnO2 nanosheets, forming a 3D multilevel porous conductive structure via vacuum freeze-drying. The sandwich-like architecture possesses multiple functions as a flexible anode for lithium-ion batteries. Micrometer-sized pores among the continuously waved rGO layers could extraordinarily improve ion diffusion. Nano-sized pores among the MnO2 nanosheets and CNT/rGO@MnO2 particles could provide vast accessible active sites and alleviate volume change. The tight connection between MnO2 and carbon skeleton could facilitate electron transportation and enhance structural stability. Due to the special structure, the rGO-wrapped CNT/rGO@MnO2 porous film as an anode shows a high capacity, excellent rate performance, and superior cycling stability (1344.2 mAh g-1 over 630 cycles at 2 A g-1 , 608.5 mAh g-1 over 1000 cycles at 7.5 A g-1 ). Furthermore, the evolutions of microstructure and chemical valence occurring inside the electrode after cycling are investigated to illuminate the structural superiority for energy storage. The excellent electrochemical performance of this freestanding flexible electrode makes it an attractive candidate for practical application in flexible energy storage.

15.
Plants (Basel) ; 13(13)2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38999689

RESUMO

The low nutrient content of soil in desert ecosystems results in unique physiological and ecological characteristics of plants under long-term water and nutrient stress, which is the basis for the productivity and stability maintenance of the desert ecosystem. However, the relationship between the soil and the plant nutrient elements in the desert ecosystem and its mechanism for maintaining ecosystem stability is still unclear. In this study, 35 sampling sites were established in an area with typical desert vegetation in the Qaidam Basin, based on a drought gradient. A total of 90 soil samples and 100 plant samples were collected, and the soil's physico-chemical properties, as well as the nutrient elements in the plant leaves, were measured. Regression analysis, redundancy analysis (RDA), the Theil-Sen Median and Mann-Kendall methods, the structural equation model (SEM), and other methods were employed to analyze the distribution characteristics of the soil and plant nutrient elements along the drought gradient and the relationship between the soil and leaf nutrient elements and its impact on ecosystem stability. The results provided the following conclusions: Compared with the nutrient elements in plant leaves, the soil's nutrient elements had a more obvious regularity of distribution along the drought gradient. A strong correlation was observed between the soil and leaf nutrient elements, with soil organic carbon and alkali-hydrolyzed nitrogen identified as important factors influencing the leaf nutrient content. The SEM showed that the soil's organic carbon had a positive effect on ecosystem stability by influencing the leaf carbon, while the soil's available phosphorus and the mean annual temperature had a direct positive effect on stability, and the soil's total nitrogen had a negative effect on stability. In general, the soil nutrient content was high in areas with a low mean annual temperature and high precipitation, and the ecosystem stability in the area distribution of typical desert vegetation in the Qaidam Basin was low. These findings reveal that soil nutrients affect the stability of desert ecosystems directly or indirectly through plant nutrients in the Qaidam Basin, which is crucial for maintaining the stability of desert ecosystems with the background of climate change.

16.
Metabolites ; 14(6)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38921433

RESUMO

This study aimed to explore the potential antioxidant activity and mechanism of oligopeptides from sauce-aroma Baijiu. The oligopeptides of Val-Leu-Pro-Phe (VLPF), Pro-Leu-Phe (PLF), Val-Gly-Phe-Cys (VGFC), Leu-Tyr-Pro (LYP), Leu-Pro-Phe (LPF), and Phe-Thr-Phe (FTF) were identified by liquid chromatography-mass spectrometry (LC-MS) from the mixed-distillate of Baijiu fermented grains and soy sauce residue (MDFS). The antioxidant mechanism of these oligopeptides on scavenging DPPH•, ABTS•+, and hydroxide radicals was investigated, respectively. Among them, VGFC had the strongest potential antioxidant activity, which was responsible for its hydrogen bonds with these radicals with high affinity. The binding energies between VGFC and these radicals were -1.26 kcal/mol, -1.33 kcal/mol, and -1.93 kcal/mol, respectively. Additionally, free radicals prefer to bind the oligopeptide composed of hydrophobic amino acid residues such as Leu, Val, Phe, and Pro, thus being scavenged for exerting antioxidant activity. It provided a new idea for the development and utilization of bioactive oligopeptides in sauce-aroma Baijiu.

17.
Anaerobe ; 22: 97-103, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23792230

RESUMO

Eighty-five strains of lactobacillus were isolated from the pig intestine and identified by sequencing analysis based on 16S rRNA gene, from which five lactobacillus strains with high adhesive ability were selected. The inhibition ability of the five lactobacillus strains with or without S-layer proteins against adherence of Escherichia coli K88 and Salmonella enteritidis 50335 to Caco-2 was evaluated in vitro with Lactobacillus rhamnosus GG strain (LGG) as a positive control. In addition, tolerance of lactobacilli to heat, acid, bile, Zn(2+) and Cu(2+) were assessed. All five selected strains, Lactobacillus salivarius ZJ614 (JN981856), Lactobacillus reuteri ZJ616 (JN981858), L. reuteri ZJ617 (JN981859), L. reuteri ZJ621 (JN981863) and L. reuteri ZJ623 (JN981865), showed inhibition against the two pathogens, E. coli K88 and S. enteritidis 50335. L. reuteri ZJ621 showed higher inhibition ability than the others to S. enteritidis 50335 (P < 0.05). Sodium dodecyl sulfate-Polyacrylamide gel electrophoresis (SDS-PAGE) analysis indicated that all five strains had abundant bands with molecular weight ranging from 34 to 130 KDa as well as had a common band of approximately 42 KDa. After treatment with 5 M LiCl to remove S-layer protein, the inhibition activities of the lactobacilli against pathogens decreased significantly (P < 0.05). The results showed that higher adhesive ability means higher inhibition activity for lactobacillus against pathogen, in which S-layer proteins plays an important role.


Assuntos
Aderência Bacteriana/fisiologia , Células CACO-2/microbiologia , Lacticaseibacillus rhamnosus/fisiologia , Limosilactobacillus reuteri/fisiologia , Glicoproteínas de Membrana/metabolismo , Animais , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/patogenicidade , Humanos , Intestinos/microbiologia , Salmonella enteritidis/crescimento & desenvolvimento , Salmonella enteritidis/patogenicidade , Suínos/microbiologia
18.
Sci Rep ; 13(1): 20398, 2023 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-37989782

RESUMO

Speech emotion analysis is one of the most basic requirements for the evolution of Artificial Intelligence (AI) in the field of human-machine interaction. Accurate emotion recognition in speech can be effective in applications such as online support, lie detection systems and customer feedback analysis. However, the existing techniques for this field have not yet met sufficient development. This paper presents a new method to improve the performance of emotion analysis in speech. The proposed method includes the following steps: pre-processing, feature description, feature extraction, and classification. The initial description of speech features in the proposed method is done by using the combination of spectro-temporal modulation (STM) and entropy features. Also, a Convolutional Neural Network (CNN) is utilized to reduce the dimensions of these features and extract the features of each signal. Finally, the combination of gamma classifier (GC) and Error-Correcting Output Codes (ECOC) is applied to classify features and extract emotions in speech. The performance of the proposed method has been evaluated using two datasets, Berlin and ShEMO. The results show that the proposed method can recognize speech emotions in the Berlin and ShEMO datasets with an average accuracy of 93.33 and 85.73%, respectively, which is at least 6.67% better than compared methods.


Assuntos
Inteligência Artificial , Fala , Humanos , Redes Neurais de Computação , Aprendizado de Máquina , Emoções
19.
Materials (Basel) ; 16(14)2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37512243

RESUMO

The attainment of the desired strength of the Inconel 718 superalloy heavily relies on the isothermal aging process, which plays a critical role in achieving the anticipated hardening effect. Surprisingly, there remains a dearth of dedicated studies investigating the influence of homogenization on phase transformations during the isothermal aging process, leaving a gap in the knowledge required to guide the design of post-heat treatment strategies. Addressing this gap, our work investigates the impact of homogenization time on phase transformations during isothermal aging at 730 °C in Inconel 718 alloys produced via additive manufacturing (AM) and suction casting (SC) methods. Intriguingly, we observe contrasting behaviors in the particle size of γ″ and γ' in aged samples, depending on the homogenization time and the alloy processing method. Specifically, in AM alloys, extended homogenization time leads to an increase in the particle size of γ″ and γ', whereas the opposite trend is observed in SC alloys. Furthermore, despite undergoing the same heat treatment, the AM alloys exhibit smaller particle sizes but higher precipitate number densities compared to the SC alloys, resulting in superior hardness. Notably, pronounced grain refinement during aging is evident in 1 h homogenized SC samples under 1180 °C, warranting further investigations into the underlying mechanisms. This study elucidates the crucial role of homogenization in attaining the desired microstructure following subsequent aging processes. Moreover, it offers novel insights for developing post-heat treatment strategies for superalloys.

20.
J Ethnopharmacol ; 300: 115702, 2023 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-36099982

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: In traditional Chinese medicine (TCM) theory, depression is an emotional disease, which is thought to be related to stagnation of liver qi and dysfunction of the spleen in transport. Xiaoyao San (XYS) is considered to have the effects of soothing liver-qi stagnation and invigorating the spleen. The spleen has the function to transport and transform nutrients. The liver has also termed the center of energy metabolism in the body. Therefore, exploring the antidepressant effects of XYS from the perspective of energy metabolism may reveal new findings. AIM OF THE STUDY: Glucose catabolism is an important part of energy metabolism. In recent years, several researchers have found that XYS can exert antidepressant effects by modulating abnormalities in glucose catabolism-related metabolites. The previous research of our research group found that the hippocampus glucose catabolism was disordered in depression. However, the antidepressant potential of XYS through modulating the disorders of hippocampal glucose catabolism and the specific metabolic pathways and targets of XYS action were still unknown. The aim of this study was to address the above scientific questions. MATERIALS AND METHODS: In this research, the CUMS (chronic unpredictable mild stress) model was used as the animal model of depression. The antidepressant effect of XYS was evaluated by behavioral indicators. The specific pathways and targets of XYS modulating the disorders of glucose catabolism in the hippocampus of CUMS rats were obtained by stable isotope-resolved metabolomics. Further, the isotope tracing results were also verified by molecular biology and electron transmission electron microscopy. RESULTS: The results demonstrated that XYS pretreatment could significantly improve the depressive symptoms induced by CUMS. More importantly, it was found that XYS could modulate the disorders of glucose catabolism in the hippocampus of CUMS rats. Stable isotope-resolved metabolomics and enzyme activity tests showed that Lactate dehydrogenase (LDH), Pyruvate carboxylase (PC), and Pyruvate dehydrogenase (PDH) were targets of XYS for modulating the disorders of glucose catabolism in the hippocampus of CUMS rats. The Succinate dehydrogenase (SDH) and mitochondrial respiratory chain complex V (MRCC-Ⅴ) were targets of XYS to improve abnormal mitochondrial oxidative phosphorylation in the hippocampus of CUMS rats. XYS was also found to have the ability to improve the structural damage of mitochondria and nuclei in the hippocampal caused by CUMS. CONCLUSIONS: This study was to explore the antidepressant effect of XYS from the perspective of glucose catabolism based on a strategy combining stable isotope tracing, molecular biology techniques, and transmission electron microscopy. We not only obtained the specific pathways and targets of XYS to improve the disorders of glucose catabolism in the hippocampus of CUMS rats, but also revealed the specific targets of the pathways of XYS compared with VLF.


Assuntos
Medicamentos de Ervas Chinesas , Succinato Desidrogenase , Animais , Antidepressivos/farmacologia , Antidepressivos/uso terapêutico , Comportamento Animal , Depressão/psicologia , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Glucose/farmacologia , Hipocampo/metabolismo , Isótopos/metabolismo , Isótopos/farmacologia , Lactato Desidrogenases/metabolismo , Metabolômica/métodos , Piruvato Carboxilase , Piruvatos/farmacologia , Ratos , Estresse Psicológico/tratamento farmacológico , Succinato Desidrogenase/metabolismo
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